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WO2020079119A1 - Procédé de fourniture de concentrés de polyacrylamide aqueux - Google Patents

Procédé de fourniture de concentrés de polyacrylamide aqueux Download PDF

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Publication number
WO2020079119A1
WO2020079119A1 PCT/EP2019/078157 EP2019078157W WO2020079119A1 WO 2020079119 A1 WO2020079119 A1 WO 2020079119A1 EP 2019078157 W EP2019078157 W EP 2019078157W WO 2020079119 A1 WO2020079119 A1 WO 2020079119A1
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Prior art keywords
aqueous
polymerization
unit
acrylamide
location
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English (en)
Inventor
Faissal-Ali El-Toufaili
Dennis Loesch
Anna-Corina SCHMIDT
Tobias Joachim Zimmermann
Markus OSTERMAYR
Jack Tinsley
Brent Busby
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BASF SE
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BASF SE
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F20/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
    • C08F20/02—Monocarboxylic acids having less than ten carbon atoms, Derivatives thereof
    • C08F20/52—Amides or imides
    • C08F20/54—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
    • C08F20/56—Acrylamide; Methacrylamide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/01—Processes of polymerisation characterised by special features of the polymerisation apparatus used
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/52—Amides or imides
    • C08F220/54—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
    • C08F220/56—Acrylamide; Methacrylamide

Definitions

  • the present invention relates to a method of providing aqueous polyacrylamide concentrates, wherein the process comprises preparing the concentrates at a location A by radically polymerizing an aqueous monomer solution comprising at least water and 1 % to 14.9 % by weight -relating to the total of all components of the aqueous monomer solution- of water-soluble, monoethylenically unsaturated monomers, wherein said water-soluble, monoethylenically unsaturated monomers comprise at least acrylamide and transporting the obtained aqueous polyacrylamide concentrates to a different location B by transport means selected from the group of trucks, railcars or ships.
  • Water-soluble, high molecular weight homo- and copolymers of acrylamide may be used for various applications such as mining and oilfield applications, water treatment, sewage treatment, papermaking, and agriculture. Examples include its use in the exploration and production of mineral oil, in particular as thickener in aqueous injection fluids for enhanced oil recovery or as rheology modifier for aqueous drilling fluids.
  • Further examples include its use as flocculating agent for tailings and slurries in mining activities.
  • a common polymerization technology for manufacturing polyacrylamides is the so called“gel polymerization”.
  • gel polymerization an aqueous monomer solution having a relatively high concentration of monomers, for example from 20 % by weight to 50 % by weight is polymerized by means of suitable polymerization initiators under essentially adiabatic conditions in an unstirred reactor thereby forming a polymer gel.
  • the polymer gels formed are converted to polymer powders by comminuting the gel into smaller pieces by one or more size reduction steps, drying such gel pieces for example in a fluid bed dryer followed by sieving, grinding and packaging.
  • the obtained polyacrylamide powders are thereafter packaged and shipped to customers.
  • the aqueous polyacrylamide gel obtained from gel polymerization typically comprises from 65 % to 80 % of water.
  • the residual amount of water in polyacrylamide powders typically is from about 4 to 12 % by weight. So,“drying” such polyacrylamide gels does not mean removing only some residual moisture in course of drying but rather removing about 0.55 to 0.75 kg of water per kg of polymer gel, or -with other words- per kg of polymer powder produced also 1.5 to 2.5 kg of water are“produced”.
  • Polyacrylamides are usually used as dilute aqueous solutions. Typical concentrations of polyacrylamides for oilfield and mining applications range from 0.05 wt. % to 0.5 wt. %. Consequently, the polyacrylamide powders manufactured as mentioned above need to be dissolved in aqueous fluids before use. Dissolving high molecular weight polymers in aqueous fluids is time consuming and it is difficult to do so without degrading the polymers and without forming lumps. Suitable equipment for dissolving polyacrylamide powders is necessary on-site.
  • DE 2 059 241 discloses a process for preparing water-soluble polymers, including acrylamide containing polymers, in which an aqueous solution comprising water- soluble monomers and polymerization initiators is filled into transportable containers for polymerization. In the transportable containers, the aqueous solution polymerizes thereby forming polymer gel. The gel may be transported to the end users who can remove the polymer gels and dissolve them in water.
  • the transportable containers may be -for instance- bags, cans, drums, or boxes having a volume from 2 I to 200 I.
  • US 4,248,304 discloses a process for recovering oil from subterranean formations wherein a water-in-oil-emulsion of an acrylamide polymer in the presence of an inverting agent is injected into the formation.
  • the water-in-oil emulsion is manufactured in a small chemical plant located near the wells and the manufacturing procedure comprises the steps of forming a water-in-oil emulsion of acrylonitrile, converting a substantially portion of the acrylonitrile to acrylamide using a suitable catalyst, and polymerizing the water-in-oil emulsion of acrylamide in the presence of a free radical polymerization catalyst.
  • the catalyst may be a copper catalyst.
  • ZA 8303812 discloses a process for preparing polyacrylamides comprising polymerizing acrylamide and optionally suitable comonomers on-site and transferring the polymer formed to its desired place of use on site without drying or concentrating.
  • the polymerization can be carried out as an emulsion polymerization, bead
  • the polymer may be pumped from the polymerization reactor to the position on site where it is used.
  • WO 84/00967 A1 discloses an apparatus and method for the continuous production of aqueous polymer solutions, in particular partially hydrolyzed polyacrylamide.
  • the apparatus comprises a polymerization reactor, a hydrolysis reactor and a diluter.
  • the polymerization may be performed on-site and the solutions may be used in secondary or tertiary oil recovery.
  • US 4,605,689 discloses a process for producing a dilute polyacrylamide solution comprising the steps of providing a polyacrylamide gel comprising from about 6 % by weight to 15 % by weight of solids, conveying such gel together with a minor amount of aqueous solvent through at least one static cutting device thereby obtaining a slurry of small gel particles in water, and dissolving the gel particles in the aqueous solvent thereby obtaining a homogeneous solution concentrate which is readily diluted with aqueous solvent thereby obtaining a diluted aqueous polyacrylamide solution.
  • US 4,845,192 discloses a method of rapidly dissolving particles of gels of water-soluble polymers comprising forming a suspension of such gel particles in water and subjecting said suspension to instantaneous and momentary conditions of high shearing effective to finely slice said particles.
  • WO 2017/186567 A1 relates to a process for producing an aqueous polymer solution comprising the steps of providing an aqueous polyacrylamide gel comprising at least 10 % by weight of active polymer, cutting the aqueous polyacrylamide gel by means of an aqueous liquid at a pressure of at least 150 bar to reduce the size of the aqueous polyacrylamide gel, and dissolving the aqueous polyacrylamide gel in an aqueous liquid.
  • WO 2017/186697 A1 relates to a method of preparing an aqueous polyacrylamide solution, comprising hydrolyzing acrylonitrile in water in presence of a biocatalyst thereby obtaining an acrylamide solution, directly polymerizing the acrylamide solution thereby obtaining a polyacrylamide gel comprising at least 10 % by weight of polyacrylamides, preferably form 16 % to 50 % by weight, and directly dissolving the polyacrylamide gel by addition of water thereby obtaining an aqueous polyacrylamide solution, which may have a concentration from 0.03 % to 5 % by weight.
  • the method may be carried out on-site.
  • WO 2017/186685 A1 relates to a method of preparing an aqueous polyacrylamide solution, comprising hydrolyzing acrylonitrile in water in presence of a biocatalyst thereby obtaining an acrylamide solution, directly polymerizing the acrylamide solution thereby obtaining a polyacrylamide gel comprising at least 10 % by weight of polyacrylamides, preferably form 16 % to 50 % by weight, and directly dissolving the polyacrylamide gel by addition of water by means of a mixer comprising a rotatable impeller thereby obtaining an aqueous polyacrylamide solution, which may have a concentration from 0.03 % to 5 % by weight.
  • the method may be carried out on-site.
  • WO 2017/186698 A1 relates to a method of preparing an aqueous polyacrylamide solution, comprising hydrolyzing acrylonitrile in water in presence of a biocatalyst thereby obtaining an acrylamide solution, directly polymerizing the acrylamide solution thereby obtaining a polyacrylamide gel comprising at least 10 % by weight of polyacrylamides, preferably form 16 % to 50 % by weight, and directly dissolving the polyacrylamide gel by addition of water by means of water-jet cutting, thereby obtaining an aqueous polyacrylamide solution, which may have a concentration from 0.03 % to 5 % by weight.
  • the method may be carried out on-site.
  • WO 2016/006556 A1 describes a method for producing a compound using a continuous tank reactor which is provided with two or more reaction tanks for producing the compound and with a reaction liquid feeding pipe that feeds a reaction liquid from an upstream reaction tank to a downstream reaction tank, said method being characterized in that the Reynold's number of the reaction liquid that flows in the reaction liquid feeding pipe is configured to be 1800-22000.
  • the tank reactor may be mounted in a portable container.
  • the compound may be acrylamide produced by conversion from acrylonitrile by means of a biocatalyst.
  • WO 2017/167803 A1 discloses a method for producing a polyacrylamide solution having an increased viscosity by preparing an aqueous acrylamide solution by converting acrylonitrile to acrylamide using a biocatalyst, separating the biocatalyst from the aqueous acrylamide solution such that the O ⁇ boo of the aqueous acrylamide solution is equal or less than 0.6, and polymerizing the aqueous acrylamide solution thus obtained to polyacrylamide.
  • WO 97/21827 A1 discloses a process for making a solution of ammonium acrylate by enzymatic hydrolysis of acrylonitrile.
  • WO 2019/081318 A1 discloses the manufacture of aqueous polyacrylamide solutions on-site in modular plants.
  • aqueous solutions comprising acrylamide and optionally further monoethylenically unsaturated comonomers are polymerized by adiabatic gel polymerization in a transportable polymerization unit.
  • the monomer concentration may be from 5 % by weight to 45 % by weight.
  • Such a polymerization may be performed at a location A and thereafter the relocatable polymerization unit filled with the aqueous polyacrylamide gel is transported to another location B where the gel is removed from the polymerization unit, comminuted and dissolved in water thereby yielding an aqueous polyacrylamide solution.
  • Location B typically is a location where the aqueous polyacrylamide solutions are used, e.g. at an oil well or in mining area.
  • Location A typically is a central hub comprising units for monomer storage, monomer make-up and polymerization which serves a number of different locations B with aqueous polyacrylamide gel. Locations A and B may be apart from each other significantly, for example the distance may be up to 3000 km and the transport of the gel form location A to location B may last several days.
  • the present invention relates to a method of providing aqueous polyacrylamide concentrates, characterized in that the process comprises at least the following steps:
  • concentrates are provided to a to a site-of-use (hereinafter also“location B”), i.e. to a location where the concentrates are used.
  • the concentrates are manufactured by radically polymerizing an aqueous monomer solution comprising at least water and 1 % to 14.9 % by weight -relating to the total of all components of the aqueous monomer solution- of water-soluble, monoethylenically unsaturated monomers, wherein said water-soluble, monoethylenically unsaturated monomers comprise at least acrylamide.
  • the manufacture is carried out in modular, relocatable plants at a manufacturing-site (hereinafter also“location A”) which is apart from the site of use, and the concentrates are transported to location B for further use.
  • location A manufacturing-site
  • polyacrylamides as used herein means water-soluble homopolymers of acrylamide, or water-soluble copolymers comprising at least 10 %, preferably at least 20 %, and more preferably at least 30 % by weight of acrylamide and at least one additional water-soluble, monoethylenically unsaturated monomer different from acrylamide, wherein the amounts relate to the total amount of all monomers in the polymer. Copolymers are preferred.
  • water-soluble monomers in the context of this invention means that the monomers are to be soluble in the aqueous monomer solution to be used for polymerization in the desired use concentration. It is thus not absolutely necessary that the monomers to be used are miscible with water without any gap; instead, it is sufficient if they meet the minimum requirement mentioned. It is to be noted that the presence of acrylamide in the monomer solution might enhance the solubility of other monomers as compared to water only. In general, the solubility of the water-soluble monomers in water at room temperature should be at least 50 g/l, preferably at least 100 g/l.
  • the kind and amount of water-soluble, monoethylenically unsaturated comonomers to be used besides acrylamide is not limited and depends on the desired properties and the desired use of the aqueous solutions of polyacrylamides to be manufactured.
  • comonomers may be selected from uncharged water-soluble, monoethylenically unsaturated monomers.
  • examples comprise methacrylamide, N-methyl(meth)acrylamide, N,N’-dimethyl(meth)acrylamide, N- methylol(meth)acrylamide or N-vinylpyrrolidone. Further examples have been mentioned in WO 2015/158517 A1 page 7, lines 9 to 14.
  • comonomers may be selected from water- soluble, monoethylenically unsaturated monomers comprising at least one acidic group, or salts thereof.
  • the acidic groups are preferably selected from the group of - COOH, -SO3H and -PO3H2 or salts thereof. Preference is given to monomers comprising COOH groups and/or -SO3H groups or salts thereof.
  • suitable counterions include alkaline earth metals such as Ca 2+ ion, alkali metal ions such as Li + , Na + or K + , and also ammonium ions such as NH 4 + or ammonium ions having organic radicals.
  • ammonium ions having organic radicals include [NH(CH3)3] + , [NH 2 (CH 3 ) 2 ] + , [NH 3 (CH 3 )] + , [NH(C 2 H 5 ) 3 ] + , [NH 2 (C 2 H 5 ) 2 ] + , [NH 3 (C 2 H 5 )] + ,
  • Examples of monomers comprising -COOH groups include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid or fumaric acid or salts thereof.
  • Examples of monomers comprising -SO 3 H groups or salts thereof include vinylsulfonic acid, allylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (ATBS), 2- methacrylamido-2-methylpropanesulfonic acid, 2-acrylamidobutanesulfonic acid, 3- acrylamido-3-methylbutanesulfonic acid or 2-acrylamido-2,4,4-trimethylpentanesulfonic acid. Preference is given to 2-acrylamido-2-methylpropanesulfonic acid (ATBS) or salts thereof.
  • ATBS 2-acrylamido-2-methylpropanesulfonic acid
  • Examples of monomers comprising -P0 3 H 2 groups or salts thereof include
  • vinylphosphonic acid allylphosphonic acid, N-(meth)acrylamidoalkylphosphonic acids or (meth)acryloyloxyalkylphosphonic acids, preferably vinylphosphonic acid.
  • Preferred monomers comprising acidic groups comprise acrylic acid and/or ATBS or salts thereof.
  • comonomers may be selected from water- soluble, monoethylenically unsaturated monomers comprising cationic groups.
  • comonomers may be selected from associative monomers.
  • Associative monomers impart hydrophobically associating properties to
  • Associative monomers to be used in the context of this invention are water-soluble, monoethylenically unsaturated monomers having at least one hydrophilic group and at least one, preferably terminal, hydrophobic group. Examples of associative monomers have been described for example in WO 2010/133527, WO 2012/069478, WO 2015/086468 or WO 2015/158517.
  • “Hydrophobically associating copolymers” are understood by a person skilled in the art to mean water-soluble copolymers which, as well as hydrophilic units (in a sufficient amount to assure water solubility), have hydrophobic groups in lateral or terminal positions. In aqueous solution, the hydrophobic groups can associate with one another. Because of this associative interaction, there is an increase in the viscosity of the aqueous polymer solution compared to a polymer of the same kind that merely does not have any associative groups.
  • the linking hydrophilic R 2 group may be a group comprising ethylene oxide units, for example a group comprising 5 to 80 ethylene oxide units, which is joined to the
  • H2C C(R 1 )- group in a suitable manner, for example by means of a single bond or of a suitable linking group.
  • the hydrophilic linking group R 2 may be a group comprising quaternary ammonium groups.
  • R 3a is an aliphatic and/or aromatic, straight-chain or branched hydrocarbyl radical having 8 to 40 carbon atoms, preferably 12 to 32 carbon atoms.
  • groups include n-octyl, n-decyl, n-dodecyl, n-tetradecyl, n-hexadecyl or n-octadecyl groups.
  • the groups are aromatic groups, especially substituted phenyl radicals, especially distyrylphenyl groups and/or tristyrylphenyl groups.
  • n is a natural number from 2 to 6, for example 4
  • x is a number from 10 to 50, preferably from 12 to 40, and for example, from 20 to 30
  • y is a number from 5 to 30, preferably 8 to 25.
  • z is a number from 0 to 5, for example 1 to 4, i.e. the terminal block of ethylene oxide units is thus merely optionally present.
  • it is possible to use at least two monomers (V), wherein the R 1 and R 6 radicals and indices n, x and y are each the same, but in one of the monomers z 0 while z > 0 in the other, preferably 1 to 4.
  • the associative monomers are cationic monomers.
  • cationic associative monomers have been disclosed in WO 2015/158517 A1 , page 1 1 , line 20 to page 12, lines 14 to 42.
  • water-soluble monoethylenically unsaturated monomers also water-soluble, ethylenically unsaturated monomers having more than one ethylenic group may be used.
  • Monomers of this kind can be used in special cases in order to achieve easy crosslinking of the acrylamide polymers.
  • the amount thereof should generally not exceed 2% by weight, preferably 1 % by weight and especially 0.5% by weight, based on the sum total of all the monomers. More preferably, the monomers to be used in the present invention are only monoethylenically unsaturated monomers.
  • composition of the polyacrylamides to be manufactured according the process of the present invention may be selected according to the desired use of the polyacrylamides.
  • Preferred polyacrylamides comprise, besides at least 10 % by weight of acrylamide, at least one water-soluble, monoethylenically unsaturated comonomer, preferably at least one comonomer selected from the group of acrylic acid or salts thereof, ATBS or salts thereof, associative monomers, in particular those of formula (V) or DMA3Q, more preferably at least one comonomer selected from acrylic acid or salts thereof, ATBS or salts thereof, associative monomers, in particular those of formula (V).
  • the polyacrylamides comprise 20 % to 90 % by weight of acrylamide and 10 % to 80 % by weight of acrylic acid and/or salts thereof, wherein the amounts of the monomers relate to the total of all monomers in the polymer.
  • the polyacrylamides comprise 20 % to 40 % by weight of acrylamide and 60 % to 80 % by weight of acrylic acid and/or salts thereof. In one embodiment, the polyacrylamides comprise 55 % to 75 % by weight of acrylamide and 25 % to 45 % by weight of acrylic acid and/or salts thereof.
  • the polyacrylamides comprise 45 % to 75 % by weight of acrylamide and 25 % to 55 % by weight of ATBS and/or salts thereof.
  • the polyacrylamides comprise 30 % to 80 % by weight of acrylamide, 10 % to 40 % by weight of acrylic acid and/or salts thereof, and 10 % to 40 % by weight of ATBS and/or salts thereof.
  • the polyacrylamides comprise 45 % to 75 % by weight of acrylamide, 0.1 to 5 %, preferably 0.1 to 2 % by weight of at least one associative monomer of the general formulas (I) or (II) mentioned above and 10 to 54.9 % by weight of acrylic acid and/or ATBS and/or salts thereof.
  • the associative monomer(s) have the general formula (V) including the preferred embodiments mentioned above.
  • the polyacrylamides comprise 60 % to 75 % by weight of acrylamide, 0.1 to 5 %, preferably 0.1 to 2 % by weight of at least one associative monomer of the general formula (V) mentioned above, including the preferred embodiments, and 20 to 39.9 % by weight of acrylic acid or salts thereof.
  • the polyacrylamides comprise 45 % to 55 % by weight of acrylamide, 0.1 to 5 %, preferably 0.1 to 2 % by weight of at least one associative monomer of the general formula (V) mentioned above, including the preferred embodiments, and 40 to 54.9 % by weight of acrylic acid or salts thereof.
  • the polyacrylamides comprise 60 % to 99 % by weight of acrylamide and 1 % to 40 % by weight of DMA3Q.
  • the polyacrylamides comprise 10 % to 50 % by weight of acrylamide and 50 % to 90 % by weight of DMA3Q.
  • the polyacrylamides comprise 90 to 99.5 % by weight of acrylamide, 0.5 to 2 % by weight of at least one associative monomer, and 0 % to 9.5 % by weight of and anionic monomer, for example ATBS or a cationic monomer, for example DM3AQ.
  • the associative monomer(s) have the general formula (V) including the preferred embodiments mentioned above.
  • the amount of the monomers relates to the total of all monomers in the polyacrylamide.
  • Further water-soluble, monoethylenically unsaturated monomers may be present besides those specifically mentioned, however, the embodiments each include also one embodiment in which besides the monomers specifically mentioned no further monomers are present, i.e. in these embodiments the total amount of the monomers specifically mentioned is 100 % by weight.
  • the process for producing an aqueous polyacrylamide gel according to the present invention is carried out at two different locations A and B and includes transporting an aqueous polyacrylamide concentrate from location A to location B.
  • an aqueous monomer solution for polymerization comprising acrylamide is prepared (step [1]) and the monomer solution is polymerized in a polymerization unit (step [2]) thereby obtaining an aqueous polyacrylamide gel hold in the polymerization unit.
  • the step of manufacturing acrylamide by hydrolysis of acrylonitrile by means of a biocatalyst is also performed at location A.
  • step [3] either a transportable polymerization unit filled with the aqueous
  • polyacrylamide gel is transported from location A to a different location B by transport means selected from the group of trucks, railcars or ships or the aqueous
  • polyacrylamide gel is removed from the polymerization unit, transferred to a suitable transport unit and the transport unit filled with the aqueous polyacrylamide gel is transported from location A to a different location B by transport means selected from the group of trucks, railcars or ships.
  • Location B is a location at which polyacrylamides are used or at least a location close to such a location of use.
  • the aqueous polyacrylamide gel is removed from the transport unit and/or the polymerization unit (step [4]). It may be used as such or alternatively, the gel may be further diluted with further aqueous liquid at location B.
  • location B may be at an oil and/or gas well to be treated with aqueous polyacrylamide solutions. In another embodiment, location B may be in between a plurality of such oil and/or gas wells or at one of them and the aqueous polyacrylamide gel is distributed to all injection wells.
  • location B may be a location at or close to a tailings ponds in which mineral tailings are dewatered using aqueous polyacrylamide solutions.
  • location B may be a location for the treatment of red mud, a by-product of the Bayer process for manufacturing aluminium.
  • location B may be at a paper production site, at sewage works, at seawater desalination plants or at sites for manufacturing agricultural formulations.
  • the manufacturing-site, location A is apart from location B.
  • location A is a local hub which provides a plurality of different locations B with aqueous polyacrylamide gels.
  • the local hub is located at a central point having good transport connections in order to ensure easy and economic supply with raw materials.
  • location A may at a central point over a subterranean, oil-bearing formation or a central point in between different subterranean, oil-bearing formations and from location A, a plurality of oil wells to be treated is provided with aqueous polyacrylamide gels for further processing.
  • location A is at a central point in a mining area and from location A, a plurality of tailing ponds is provided with aqueous polyacrylamide gels for further processing.
  • the distance between location A and the location(s) B is not specifically limited.
  • location A should be located close to the locations B or at least not too far apart from the locations B. Having said that, the abovementioned dimensions of mining areas or subterranean, oil-bearing formations should be kept in mind. So, even when location A is a local hub as outlined above, the local hub A and the locations B may be apart from each other up a few hundred kilometers.
  • the distance between location A and location(s) B may range from 1 to 500 km, in particular from 10 km to 300 km, for example from 10 to 150 km or from 20 km to 100 km.
  • the steps of the present invention are carried out in modular, relocatable plants.
  • Each relocatable unit bundles certain functions of the plant.
  • relocatable units comprise units for storing and optionally cooling the monomers and other raw materials, hydrolyzing acrylonitrile, mixing monomers or polymerization. Details will be provided below.
  • individual units are connected with each other in a suitable manner thereby obtaining a production line.
  • “Relocatable unit” means that the unit is transportable basically as a whole and that is it not necessary to disassemble the entire unit into individual parts for transport.
  • Transport may happen on trucks, railcars or ships.
  • such modular, relocatable units are containerized units which may be transported in the same manner as closed intermodal containers for example on trucks, railcars or ships.
  • Intermodal containers are large standardized (according to ISO 668) shipping containers, in particular designed and built for intermodal freight transport.
  • Such containers are also known as ISO containers.
  • Such ISO containers may have external dimensions of a height of ⁇ 2.59 m, a width of ⁇ 2.44 m and a length of ⁇ 6.05 m. Larger ISO containers have external dimensions of a height of ⁇ 2.59 m, a width of - 2.44 m and a length of -12.19 m.
  • the relocatable units may be fixed on trucks or on trailers. With other words, for such relocatable units not a container or something similar is deployed, but the entire truck or the trailer including the unit in its loading spaces is deployed.
  • the trucks or trailers advantageously also function as platform for the units on the ground. Also, two or more different units may be mounted together on a truck or trailer.
  • the relocatable units are combined with each other, hereby obtaining modular production plants for performing the process according to the present invention.
  • Such a modular construction using relocatable units provides the advantage, that the plants may be easily relocated if aqueous polyacrylamide solutions are no longer needed at one location but at another location.
  • Acrylamide may be synthesized by partial hydrolysis of acrylonitrile using suitable catalysts. It is known in the art to use copper catalysts or other metal containing catalysts and it is also known to use biocatalysts capable of converting acrylonitrile to acrylamide. Pure acrylamide is a solid, however, typically acrylamide -whether made by bio catalysis or copper catalysis- is provided as aqueous solution, for example as aqueous solution comprising about 50 % by wt. of acrylamide.
  • Acrylamide obtained by means of biocatalysts can be distinguished from acrylamide obtained by means of copper catalysts or other metal containing catalysts because the latter still comprises at least traces of copper or other metals.
  • Acrylamide obtained by means of biocatalysts may still comprise traces of the biocatalyst.
  • an aqueous acrylamide solution which has been obtained by hydrolyzing acrylonitrile in water in presence of a biocatalyst capable of converting acrylonitrile to acrylamide.
  • a biocatalyst capable of converting acrylonitrile to acrylamide.
  • aqueous solutions of bio acrylamide for use in the process according to the present invention may be manufactured at another location, for example in a fixed chemical plant, and shipped to location A.
  • the manufacture of bio acrylamide is performed at location A in relocatable plants (hereinafter designated as process step [0]).
  • Acrylonitrile is a liquid and may be transported as pure compound to location A.
  • the molecular weight of acrylamide is ⁇ 34 % higher than that of acrylonitrile and acrylamide is typically provided as ⁇ 50 % aqueous solution. So, for a 50 % aqueous solution of acrylamide the mass to be transported is about 2.5-fold as much as compared to transporting pure acrylonitrile.
  • Transporting pure, solid acrylamide means transporting only ⁇ 34 % more mass as compared to transporting pure acrylonitrile, however, additional equipment for handling and dissolving the solid acrylamide is necessary at location A.
  • step [0] is only optional for the process according to the present invention, however, in a preferred embodiment of the invention, the process according to the invention includes step [0].
  • step [0] acrylonitrile is hydrolyzed in water in presence of a biocatalyst capable of converting acrylonitrile to acrylamide thereby obtaining an aqueous acrylamide solution.
  • Step [0] is performed at location A.
  • Acrylonitrile for step [0] may be stored in one or more than one relocatable storage units.
  • the storage unit comprises a storage vessel.
  • the volume of the storage vessel is not specifically limited and may range from 50 m 3 to 150 m 3 , for example it may be about 100 m 3 .
  • the storage vessel should be double walled and should be horizontal. Such a construction avoids installing a pit for the collection of any leakage thereby ensuring an easier and quicker relocation of the storage unit. Double-walled vessels may be placed on every good bearing soil.
  • the storage unit furthermore comprises means for charging and discharging the vessel, means for controlling the pressure in the vessel, for example a valve for settling low-pressure or overpressure, and means for controlling the temperature of the acrylonitrile which preferably should not exceed 25°C. It furthermore may comprise means for measurement and control to the extent necessary.
  • relocatable storage units comprise relocatable cuboid, storage tanks, preferably double-walled tanks.
  • any considerable form, shape and size of container is suitable and applicable for the storage and/or provision of acrylonitrile in the sense of the present invention.
  • standard iso-tanks are applicable for the storage and/or provision of acrylonitrile.
  • tank containers having a cuboid frame, preferably a frame according to the ISO 668 norm mentioned above and one or more storage vessels mounted into the frame.
  • Such normed tank containers may be stacked and transported on trucks, railcars or ships in the same manner closed intermodal containers.
  • temperature control may be performed by any kind of temperature controlling unit. Temperature control may require -depending on the climatic conditions prevailing at location A- cooling or heating the contents of the storage units. Regarding the monomers, temperature control typically means cooling, because it should be avoided that the monomers become too hot.
  • an internal heat exchanger may be used for cooling or heating, i.e. a heat exchanger mounted inside of the storage vessel. The coolant is provided to the heat exchanger by a suitable cooling or heating unit mounted outside of the storage vessel.
  • an external temperature control cycle for example a cooling cycle is used, which comprises a pump which pumps the monomer from the storage vessel through a heat exchanger and back into the storage vessel.
  • the temperature control cycle may be a separate, relocatable temperature control unit comprising pump and heat exchanger and which is connected with the storage vessel by pipes or flexible tubes.
  • the temperature control cycle may be integrated into relocatable storage unit. It may -for example- be located at one end of the unit besides the storage vessel.
  • Figure 1 schematically represents one embodiment of a monomer storage unit comprising an integrated temperature control cycle. It comprises a frame (1).
  • the frame may in particular be a cuboid frame preferably having standardized container dimensions which eases transport.
  • the relocatable storage unit furthermore comprises a double-walled vessel mounted into the frame comprising an outer wall (2) and an inner wall (3). In other embodiments, there is no such frame (1) but the storage vessel is self-supporting.
  • the storage vessel is filled with acrylonitrile.
  • the storage unit furthermore comprises an external temperature control cycle comprising at least a pump and a temperature control unit.
  • acrylonitrile is circulated by means of a pump (4) from the storage vessel to the temperature control unit (5) and back into the storage vessel.
  • the amount of acrylonitrile to be circulated in the temperature control cycle in order to control the temperature at an acceptable level, for example below 25°C depends in particular on the outside temperature and the internal temperature envisaged. In one embodiment, 10% to 100% of the volume of acrylonitrile in the vessel may be circulated per hour.
  • Figure 2 represents schematically another embodiment of a monomer storage unit. It comprises a cuboic, preferably double-walled storage vessel (6). If necessary, the storage vessel (6) is connected with an external, relocatable temperature control unit (7).
  • Acrylonitrile may be provided to location A by road tankers, ISOtanks or rail cars and pumped into the relocatable storage vessel(s).
  • the acrylonitrile may be removed from the relocatable storage vessel through a bottom valve by means of gravity or it may be pumped, for example from the upper side using a suitable pump.
  • nitrile hydratase enzymes can be used, which are capable of catalyzing the hydrolysis of acrylonitrile to acrylamide.
  • nitrile hydratase enzymes can be produced by a variety of microorganisms, for instance microorganisms of the genus Bacillus, Bacteridium, Micrococcus, Brevibacterium, Corynebacterium, Pseudomonas, Acinetobacter, Xanthobacter, Streptomyces, Rhizobium, Klebsiella, Enterobacter, Escherichia Coli, Erwinia, Aeromonas,
  • WO 2005/054456 discloses the synthesis of nitrile hydratase within microorganisms and therein it is described that various strains of Rhodococcus rhodochrous species have been found to very effectively produce nitrile hydratase enzymes, in particular
  • Rhodococcus rhodochrous NCIMB 41 164 Such microorganisms, suitable as biocatalyst for the enzymatic conversion of acrylonitrile to acrylamide, which are known for a person skilled in the art, are able to be applied in a relocatable bioconversion unit according to the present invention. Additionally, the specific methods of culturing (or cultivation, or fermentation) and/or storing the microorganism as well as the respective sequences of polynucleotides which are encoding the enzyme, particularly the nitrile hydratase, are known in the art, e.g. WO 2005/054456, WO 2016/050816, and are applicable in context of the present invention. Within the present invention nitrile hydratase and amidase producing microorganisms may be used for converting a nitrile compound into the corresponding amide compound as it is described for example in WO 2016/050816.
  • nitrile hydratase (NHase) producing microorganism or“microorganism” or “biocatalysts” or the like, have the meaning to be able to produce (i.e. they encode and express) the enzyme nitrile hydratase (also referred to as, e.g., NHase) either per se (naturally) or they have been genetically modified respectively.
  • nitrile hydratase also referred to as, e.g., NHase
  • Microorganisms which have been“genetically modified” means that these microorganisms have been manipulated such that they have acquired the capability to express the required enzyme NHase, e.g. by way of incorporation of a naturally and/or modified nitrile hydratase gene or gene cluster or the like.
  • Produced products of the microorganisms that can be used in the context of the present invention are also contemplated, e.g. suspensions obtained by
  • nitrile hydratase (NHase) producing microorganism or“microorganism” or “biocatalysts” or the like, include the cells and/or the processed product thereof as such, and/or suspensions containing such microorganisms and/or processed products. It is also envisaged that the microorganisms and/or processed products thereof are further treated before they are employed in the embodiments of the present invention. “Further treated” thereby includes for example washing steps and/or steps to concentrate the microorganism etc. It is also envisaged that the microorganisms that are employed in the embodiments of the present invention have been pre-treated by a for example drying step.
  • the microorganism can be grown in a medium containing acetonitrile or acrylonitrile as an inducer of the nitrile hydratase.
  • the biocatalyst for converting acrylonitrile to acrylamide may be obtained from culturing the microorganism in a suitable growth medium.
  • the growth medium also called fermentation (culture) medium, fermentation broth, fermentation mixture, or the like, may comprise typical components like sugars, polysaccharides, which are for example described in WO 2005/054489 and which are suitable to be used for the culturing the microorganism of the present inventions to obtain the biocatalyst.
  • the fermentation broth preferably is removed in order to prevent putrefaction, which could result in a reduction of nitrile hydratase activity.
  • the methods of storage described in WO 2005/054489 may be applied according to the present invention ensuring sufficient biocatalyst stability during storage.
  • the storage does not influence biocatalytic activity or does not lead to a reduction in biocatalytic activity.
  • the biocatalyst may be stored in presence of the fermentations broth components. Preferred in the sense of the present invention is that the biocatalyst may be stored in form of a frozen suspension and may be thawed before use. Further, the biocatalyst may be stored in dried form using freeze-drying, spray drying, heat drying, vacuum drying, fluidized bed drying and/or spray granulation, wherein spray drying and freeze drying are preferred.
  • the biocatalysts that are used according to the present invention in a relocatable plant can for example be cultured under any conditions suitable for the purpose in accordance with any of the known methods, for instance as described in the mentioned prior art of this specification.
  • the biocatalyst may be used as a whole cell catalyst for the generation of amide from nitrile.
  • the biocatalyst may be (partly) immobilized for instance entrapped in a gel or it may be used for example as a free cell suspension.
  • entrapment cross linkage such as glutaraldehyde-polyethyleneimine (GA-PEI) crosslinking, cross linking to a matrix and/or carrier binding etc., including variations and/or combinations of the aforementioned methods.
  • G-PEI glutaraldehyde-polyethyleneimine
  • the nitrile hydratase enzyme may be extracted and for instance may be used directly in the process for preparing the amide.
  • inactivated or partly inactivated cells such cells may be inactivated by thermal or chemical treatment.
  • the microorganisms are whole cells.
  • the whole cells may be pre-treated by a drying step. Suitable drying methods and/or drying conditions are disclosed e.g. in WO 2016/050816 and WO 2016/050861 and the know art can be applied in the context of the present invention for the use in a relocatable bioconversion unit.
  • aqueous suspension thereby includes all kinds of liquids, such as buffers or culture medium that are suitable to keep microorganisms in suspension.
  • liquids are well-known to the skilled person and include for example storage buffers at suitable pH such as storage buffers which are used to deposit microorganisms, TRIS-based buffers, saline based buffers, water in all quality grades such as distilled water, pure water, tap water, or sea water, culture medium, growing medium, nutrient solutions, or fermentation broths, for example the fermentation broth that was used to culture the
  • the aqueous suspension is frozen and thawed before use, in particular without loss in activity.
  • the biocatalyst may be provided as powder or as aqueous suspension to location A. If provided as powder it is frequently advisable to prepare an aqueous suspension before adding the catalyst into the bioconversion unit.
  • the biocatalyst suspension may be conducted by suspending the biocatalyst powder in water in a vessel comprising at least a mixing device, for example a stirrer, one or more inlets for water, the biocatalyst and optionally further additives and one outlet for the biocatalyst suspension.
  • the volume of the vessel may be for example from 0.1 m 3 to 1 m 3 .
  • the concentration of the biocatalyst in the aqueous biocatalyst suspension may be for example from 1 % to 30% by wt, for example from 10 to 20% by wt. relating to the total of all components of the aqueous suspension.
  • a biocatalyst suspension may be added directly to the bioconversion unit.
  • a concentrated suspension may be diluted before adding it to the bioconversion unit.
  • the hydrolysis of acrylonitrile to acrylamide by means of a biocatalyst is performed in a suitable bioconversion unit, preferably a relocatable bioconversion unit.
  • the bioconversion is performed by contacting a mixture comprising water and acrylonitrile with the biocatalyst.
  • the term“contacting” is not specifically limited and includes for example bringing into contact with, admixing, stirring, shaking, pouring into, flowing into, or incorporating into. It is thus only decisive that the mentioned ingredients come into contact with each other no matter how that contact is achieved.
  • step [0] comprises the following steps:
  • composition for bioconversion :
  • step (b) performing a bioconversion on the composition obtained in step (a).
  • the bioconversion can for example be conducted under any conditions suitable for the purpose in accordance with any of the known methods, for instance as described in the mentioned prior art of this specification like e.g. WO 2016/050817, WO 2016/050819, WO 2017/055518.
  • the conversion of acrylonitrile to the acrylamide may be carried out by any of a batch process and a continuous process, and the conversion may be carried out by selecting its reaction system from reaction systems such as suspended bed, a fixed bed, a fluidized bed and the like or by combining different reaction systems according to the form of the catalyst.
  • the method of the present invention may be carried out using a semi-batch process.
  • the term "semi-batch process" as used herein may comprise that an aqueous acrylamide solution is produced in a
  • a certain amount of acrylonitrile and the biocatalyst are placed in the bioconversion unit. Further acrylonitrile is then added during the bioconversion until a desired content of acrylamide of the composition is reached. After such desired content of acrylamide is reached, the obtained composition is for example partly or entirely recovered from the reactor, before new reactants are placed therein.
  • the acrylonitrile may be fed such that the content of acrylonitrile during step (b) is maintained substantially constant at a predetermined value.
  • the acrylonitrile content and/or the acrylamide content during step (b) may be monitored.
  • Methods of monitoring the acrylonitrile contents are not limited and include Fourier Transform Infrared Spectroscopy (FTIR).
  • FTIR Fourier Transform Infrared Spectroscopy
  • the heat-balance of the reaction may be used for monitoring the process. This means that monitoring via heat- balance method takes place by measuring the heat energy of the system during bioconversion and by calculating the loss of heat energy during the reaction in order to monitor the process.
  • the conversion of acrylonitrile to the acrylamide may preferably be carried out at atmospheric pressure, it may be carried out under pressure in order to increase solubility of acrylonitrile in the aqueous medium.
  • biocatalysts are temperature sensitive and the hydrolysis is an exothermic reaction temperature control is important.
  • the reaction temperature is not specifically restricted provided that it is not lower than the ice point of the aqueous medium. However, it is desirable to carry out the conversion at a temperature of usually 0 to 50°C, preferably 10 to 40°C, more preferably 15 to 30°C.
  • Further suitable condition for the bioconversion according to the present invention are for example described in WO 2017/055518 and are preferably applicable for the method in a relocatable bioconversion unit.
  • biocatalyst may vary depending on the type of biocatalyst to be used, it is preferred that the activity of the biocatalyst, which is introduced to the reactor, preferably the relocatable bioconversion unit, is in the range of about 5 to 500 U per mg of dried cells of microorganism.
  • Methods for determining the ability of a given biocatalyst (e.g. microorganism or enzyme) for catalyzing the conversion of acrylonitrile to acrylamide are known in the art.
  • activity of a given biocatalyst to act as a nitrile hydratase in the sense of the present invention may be determined as follows: First reacting 100 pi of a cell suspension, cell lysate, dissolved enzyme powder or any other preparation containing the supposed nitrile hydratase with 875 pi of a 50 mM potassium phosphate buffer and 25 mI of acrylonitrile at 25°C on an Eppendorf tube shaker at 1 ,000 rpm for 10 minutes. After 10 minutes of reaction time, samples may be drawn and immediately quenched by adding the same volume of 1.4% hydrochloric acid.
  • the concentration of acrylamide shall particularly be between 0.25 and 1.25 mmol/l - if necessary, the sample has to be diluted accordingly and the conversion has to be repeated.
  • the enzyme activity may then be deduced from the concentration of acrylamide by dividing the acrylamide concentration derived from HPLC analysis by the reaction time, which has been 10 minutes and by multiplying this value with the dilution factor between HPLC sample and original sample.
  • Activities >5 U/mg dry cell weight, preferably >25 U/mg dry cell weight, more preferably >50 U/mg dry cell weight, most preferably >100 U/mg dry cell weight indicate the presence of a functionally expressed nitrile hydratase and are considered as nitrile hydratase in context with the present invention.
  • the concentration of acrylonitrile during the bioconversion should not exceed 6 % by wt. and may for example be in the range from 0.1 % by wt. to 6 % by wt, preferably from 0.2 % by wt. to 5 % by wt., more preferably from 0.3 % by wt. to 4 % by wt., even more preferably from 0.5 % by wt. to 3 % by wt., still more preferably from 0.8 % by wt. to 2 % by wt. and most preferably from 1 % by wt. to 1.5 % by wt., relating to the total of all components of the aqueous mixture.
  • WO 2016/050818 teaches a method of additional dosing of acrylonitrile, which is suitable to be used and applied in the present invention.
  • the concentration of acrylamide in the obtained solution is in the range from 10% to 80%, preferably in the range from 20% to 70%, more preferably in the range from 30% to 65%, even more preferably in the range from 40% to 60%, most preferably in the range from 45% to 55% by weight of acrylamide monomers.
  • the reaction should be carried out in such a manner that the final concentration of acrylonitrile in the final acrylamide solution obtained does not exceed 0.1 % by weight relating to the total of all components of the aqueous solution. Typical reaction times may be from 2 to 20 h, in particular 4 h to 12 h, for example 6 h to 10 h.
  • the reactor contents is allowed to further circulate for some time to complete the reaction, for example for 1 hour to 3 hours.
  • the remaining contents of acrylonitrile should preferably be less than 100 ppm ACN.
  • Suitable reactors for performing the bioconversion are known to the skilled artisan. Examples comprise vessels of any shape, for example cylindrical or spherical vessels, or tube reactors. In one embodiment, the continuous tank reactor as disclosed in WO 2016/006556 A1 may be used for bioconversion. Further suitable reactors for the bioconversion according to the present invention are for example described in
  • reactors are preferably applicable for the process according to the present invention.
  • Such reactors comprise particularly a pumping circuit, a heat-exchanger and/or an agitating element.
  • the bioconversion unit is a relocatable bioconversion unit.
  • relocatable bioconversion unit is similar to the relocatable storage unit for acrylonitrile as described above. Using largely the same equipment for storing acrylonitrile or other monomers and the bioconversion step contributes to an economic process for manufacturing aqueous acrylamide solutions.
  • the bioconversion unit comprises a reaction vessel.
  • the volume of the reaction vessel is not specifically limited and may range from 10 m 3 to 150 m 3 , for example it may be about 20 m 3 to 50 m 3 .
  • the reaction vessel should be double walled and should be horizontal. Such a construction avoids installing a pit for the collection of any leakage thereby ensuring an easier and quicker relocation of the reaction unit.
  • the bioconversion unit furthermore comprises means for mixing the reaction mixture and means for controlling the temperature of the contents of the vessel.
  • the hydrolysis of acrylonitrile to acrylamide is an exothermal reaction and therefore heat generated in course of the reaction should be removed in order to maintain an optimum temperature for bioconversion.
  • the bioconversion unit furthermore usually comprises means for measurement and control, for example means for controlling the temperature or for controlling the pressure in the vessel.
  • the preferred bioconversion unit comprises an external temperature control cycle comprising a pump which pumps the aqueous reactor contents from the storage vessel through a heat exchanger and back into the storage vessel, preferably via an injection nozzle.
  • a separate, relocatable temperature control unit is used comprising pump and heat exchanger and which is connected with the bioconversion unit by pipes or flexible tubes.
  • the temperature control cycle is integrated into the relocatable bioconversion unit. It may -for example- be located at one end of the unit besides the reaction vessel.
  • the reaction vessel may furthermore comprise means for mixing the aqueous reaction mixture, for example a stirrer.
  • the external temperature control cycle described above may also be used as means for mixing.
  • the stream of the aqueous reaction mixture which passes through the temperature control cycle and which is injected back into the reaction vessel causes a circulation of the aqueous reaction mixture within the reaction vessel which is sufficient to mix the aqueous reaction mixture.
  • no stirrer is used for the mobile bioconversion unit.
  • a stirrer is an additional mechanical device, which increases the technical complexity.
  • a transportation step is easier, since no stirrer as additional technical component has to be removed before transportation.
  • a bioconversion unit without a stirrer offers more flexibility in form, shape, mechanical stability requirements and size for the bioconversion unit.
  • a horizontal set- up for the relocatable bioconversion unit can be realized easier without a stirrer and with mixing just via the external temperature control cycle.
  • Adding acrylonitrile to the contents of the bioconversion unit may be performed in various ways. It may be added into the reaction vessel or it may be added into the temperature control cycle, for example after the pump and before the heat exchanger or after the heat exchanger. Injecting acrylonitrile into the temperature control cycle ensures good mixing of the reaction mixture with freshly added acrylonitrile. Preferably, acrylonitrile is added between pump and heat exchanger.
  • FIG. 3 schematically represents an embodiment of the relocatable bioconversion unit with an integrated temperature control cycle.
  • the bioconversion unit comprises a frame (10), a double-walled reaction vessel mounted into the frame comprising an outer wall
  • the reaction vessel is self-supporting and there is no frame (10).
  • the reaction vessel is filled with the reaction mixture.
  • the bioconversion unit furthermore comprises an external temperature control cycle comprising at least a pump (13) and a temperature control unit (14).
  • the reaction mixture is circulated by means of a pump (13) from the reaction vessel to the temperature control unit (14) and is injected back into the storage vessel, preferably via an injection nozzle (16).
  • acrylonitrile is injected into the temperature control cycle thereby ensuring good mixing (15). It may be added before or after the temperature control unit.
  • FIG 3 shows an embodiment in which acrylonitrile is added into the temperature control cycle between the pump and the heat exchanger.
  • the stream of reaction mixture injected back into the reaction vessel causes a circulation of the reaction mixture in the reaction vessel which ensures sufficient mixing of the contents of the reaction mixture.
  • the amount of reaction mixture cycled per hour through the temperature control cycle is chosen such that sufficient mixing to the contents of the reactor as well as sufficient temperature control is achieved.
  • the amount of reaction mixture cycled per hour through the temperature control cycle may be from 100 % to 1000 % of the total volume of the reaction mixture in the bioconversion unit, in particular from 200 % to 1000 % and for example from 500% to 800%.
  • Off-gases of the bioconversion unit may comprise acrylonitrile, acrylic acid and acrylamide. If necessary, according to the applicable rules such off-gases may be treated in a manner known in the art. For example, it may be possible to combust the off-gases.
  • all off-gases containing acrylonitrile, acrylic acid and acrylamide may be washed in a scrubber.
  • the scrubber vessel may have a volume of 1 m 3 to 100 m 3 , preferably a volume of 5 m 3 to 100 m 3 , more preferably a volume of 10 m 3 to 100 m 3 . It may be for example an ISO tank or relocatable storage vessel, preferably a double walled vessel.
  • the scrubber water may preferably be collected in a tank and it may be re-used in the next bio-conversion batch.
  • reaction vessel After bioconversion, the reaction vessel comprises an aqueous solution of acrylamide, which still comprises the biocatalyst suspended therein.
  • the biocatalyst preferably becomes removed completely, essentially completely, or partially before polymerization, however, removing the biocatalyst may not be absolutely necessary in every case. Whether it is necessary to remove the biocatalyst substantially depends on two factors, namely whether remaining biocatalyst negatively affects polymerization and/or the properties of the polyacrylamide obtained and/or the biocatalyst negatively affects the application of the obtained polyacrylamide solution. In one embodiment, at least 75 %, preferably at least 90 % by weight of the biomass - relating to the total of the biomass present- should be removed.
  • the method for removing the biocatalyst is not specifically limited. Separation of the biocatalyst may take place by for example filtration or centrifugation. In other embodiments, active carbon may be used for separation purpose.
  • the aqueous acrylamide solution comprising the biocatalyst is removed from the bioconversion unit, passed through a unit for removing the biocatalyst, and thereafter the aqueous acrylamide solution is filled into a suitable storage unit for acrylamide, preferably a relocatable storage unit for acrylamide as described above.
  • the aqueous acrylamide solution comprising the biocatalyst is removed from the bioconversion unit, passed through a unit for removing the biocatalyst and thereafter the aqueous acrylamide solution is filled directly into the monomer make-up unit, i.e. without intermediate storing in an acrylamide storage unit.
  • the aqueous acrylamide solution comprising the biocatalyst is removed from the bioconversion unit and is filled directly, i.e. without removing the biocatalyst, into the monomer make-up unit.
  • the biocatalyst is still present in course of monomer make-up and is removed after preparing the aqueous monomer solution (step [1]) as described below.
  • the aqueous acrylamide solution comprising the biocatalyst is removed from the bioconversion unit, passed through a unit for removing the biocatalyst and thereafter filled back into the bioconversion unit.
  • the unit for removing the biocatalyst should comprise a buffer vessel having a volume sufficient for absorbing the contents of the bioconversion unit.
  • biocatalyst removal are for example applicable for partwise and/or complete removal of the biocatalyst. Further, it is preferred, that the completely or partly removed biocatalyst may be reused for a subsequent
  • acrylic acid or salts thereof may be used as comonomer besides acrylamide.
  • any kind of acrylic acid may be used for the process according to the present invention, for example acrylic acid obtained by catalytic oxidation of propene.
  • Acrylic acid may be provided in the acid form.
  • aqueous solutions of salts of acrylic acid may be provided, for example an aqueous sodium acrylate solutions.
  • ammonium acrylate available by enzymatic hydrolysis of acrylonitrile may be used for carrying out the process according of the present invention (hereinafter also“bio acrylate”).
  • the manufacture of ammonium acrylate by enzymatic hydrolysis of acrylonitrile is also performed at location A in a modular unit.
  • Suitable enzymes have been disclosed in WO 97/21827 A1 and the literature cited therein, and the publication describes also suitable conditions for carrying out the reaction.
  • the manufacture of bio-acrylate may be carried out using stirred tank reactors or loop reactors, and in particular, the relocatable bioconversion unit described above may also be used.
  • step [1 ] an aqueous monomer solution comprising at least water, acrylamide and optionally further water-soluble, monoethylenically unsaturated monomers is prepared. Step [1] is performed at location A.
  • step [1 ] it is possible to run step [1 ] as just-in-time-process, i.e. providing the monomers to the location A when monomers are needed and directly withdrawing the monomers from the transport vessels.
  • step [1 ] it is possible to run step [1 ] as just-in-time-process, i.e. providing the monomers to the location A when monomers are needed and directly withdrawing the monomers from the transport vessels.
  • step [1 ] it is possible to run step [1 ] as just-in-time-process, i.e. providing the monomers to the location A when monomers are needed and directly withdrawing the monomers from the transport vessels.
  • step [1 ] it is possible to run step [1 ] as just-in-time-process, i.e. providing the monomers to the location A when monomers are needed and directly withdrawing the monomers from the transport vessels.
  • step [1 ] it is possible to run step [1 ] as just-in-time-process, i.e. providing
  • the water-soluble, monoethylenically unsaturated monomers to be used may be provided as pure monomers or as aqueous solutions to location A. It is also possible to provide a mixture of two or more water-soluble, monoethylenically unsaturated monomers, in aqueous solution or as pure monomers, to location A.
  • Acrylamide and other water-soluble, monoethylenically unsaturated monomers such as acrylic acid, ATBS, or DMA3Q, or mixtures thereof preferably may be stored in relocatable storage units. Details of such relocatable storage units for monomers have already been outlined above for acrylonitrile and we refer to the description above.
  • the monomers may be provided to location A by road tankers, ISO tanks, or rail cars and pumped into the relocatable storage unit(s).
  • Relocatable storage units basically may have any shape and orientation. They may be for example cylindrical or rectangular and the storage units may be in horizontal or vertical orientation. The volume and the dimensions are only limited by the condition that the storage units are relocatable. The volume may be -by the way of example- up to 200 m 3 , for example storage units having a volume from 60 to 80 m 3 or from 120 to 180 m 3 .
  • a relocatable storage unit with integrated temperature control cycle as depicted in Figure 1 as shown above may be used for storing the monomers.
  • a relocatable storage unit with a separate, external temperature control cycle as depicted in Figure 2 as shown above may be used for storing the monomers.
  • the relocatable storage unit is a vertical cylinder having a conical section at its lower end and a bottom valve for removing the liquids.
  • a construction has the advantage that emptying can be affected simply by means of gravity. It may also comprise a cooling cycle.
  • the storage units may be connected with each other, for example by pipes, so that they can become filled and emptied together and furthermore, advantageously, only single cooling unit may be used to cool all storage units together.
  • the temperature of the monoethylenically unsaturated monomers such as acrylamide, acrylic acid, ATBS or DMA3Q should not exceed 25°C to 30°C.
  • Pure associative monomers as described above may be waxy solids and may be stored at room temperature. They may be stored as aqueous solutions, for example as aqueous solutions comprising 25 % by weight of the associative monomer. Because the amounts of associative monomers are significantly smaller than the amounts of other monoethylenically unsaturated monomers smaller storage units than that described above may be used. Acidic monomers such as acrylic acid or ATBS are often partially or completely neutralized for polymerization using suitable bases.
  • Bases such as aqueous solutions of NaOH may also be stored in storage vessels as described above.
  • a cooling cycle is not necessary.
  • a heating such as a heating element in the vessel may be necessary because concentrated NaOH freezes at about +15°C.
  • the aqueous monomer solution for polymerization to be prepared in course of step [1] comprises water and 1 % to 14.9 % by weight of water-soluble, monoethylenically unsaturated monomers, relating to the total of all components of the aqueous monomer solution.
  • the water-soluble, monoethylenically unsaturated monomers comprise at least acrylamide, preferably bio acrylamide which preferably is manufactured in step [0] also at location A. Preferred monomer concentrations are provided below.
  • the water-soluble, monoethylenically unsaturated monomers to be used are mixed with each other. All monomers and optionally additives may be mixed with each other in a single step but it may also be possible to mix some monomers and add further monomers in a second step. Also, water for adjusting the concentration of the monomers may be added. Water eventually used for rinsing lines in course of transferring the monomer solution into the
  • Examples of such further additives and auxiliaries comprise bases or acids for adjusting the pH value.
  • the pH-value of the aqueous solution is adjusted to values from pH 4 to pH 7, for example pH 6 to pH 7.
  • additives and auxiliaries comprise complexing agents, defoamers, surfactants, charge-transfer-agents or stabilizers.
  • the aqueous monomer solution comprises at least one stabilizer for the prevention of polymer degradation.
  • the stabilizers for the prevention of polymer degradation are what are called“free-radical scavengers”, i.e. compounds which can react with free radicals (for example free radicals formed by heat, light, redox processes), such that said radicals can no longer attack and hence degrade the polymer.
  • free-radical scavengers i.e. compounds which can react with free radicals (for example free radicals formed by heat, light, redox processes), such that said radicals can no longer attack and hence degrade the polymer.
  • the stabilizers may be selected from the group of non-polymerizable stabilizers and polymerizable stabilizers.
  • Polymerizable stabilizers comprise a monoethylenically unsaturated group and become incorporated into the polymer chain in course of polymerization.
  • Non-polymerizable stabilizers don’t comprise such monoethylenically unsaturated groups and are not incorporated into the polymer chain.
  • stabilizers are non-polymerizable stabilizers selected from the group of sulfur compounds, sterically hindered amines, N-oxides, nitroso compounds, aromatic hydroxyl compounds or ketones.
  • sulfur compounds include thiourea, substituted thioureas such as N,N‘- dimethylthiourea, N,N‘-diethylthiourea, N,N‘-diphenylthiourea, thiocyanates, for example ammonium thiocyanate or potassium thiocyanate, tetramethylthiuram disulfide, and mercaptans such as 2-mercaptobenzothiazole or 2- mercaptobenzimidazole or salts thereof, for example the sodium salts, sodium dimethyldithiocarbamate, 2,2‘-dithiobis(benzothiazole), 4,4‘-thiobis(6-t-butyl-m-cresol).
  • Further examples include dicyandiamide, guanidine, cyanamide, paramethoxyphenol,
  • sterically hindered amines such as 1 , 2,2,6, 6-pentamethyl-4- piperidinol and sulfur compounds, preferably mercapto compounds, especially 2- mercaptobenzothiazole or 2-mercaptobenzimidazole or the respective salts thereof, for example the sodium salts, and particular preference is given to 2- mercaptobenzothiazole or salts thereof, for example the sodium salts.
  • the amount of such non-polymerizable stabilizers -if present- may be from 0.1 % to 2.0 % by weight, relating to the total of all monomers in the aqueous monomer solution, preferably from 0.15 % to 1.0 % by weight and more preferably from 0.2 % to 0.75 % by weight.
  • the stabilizers are polymerizable stabilizers substituted by a monoethylenically unsaturated group.
  • stabilizers comprising monoethylenically unsaturated groups comprise (meth)acrylic acid esters of 1 ,2,2,6, -pentamethyl-4-piperidinol or other monoethylenically unsaturated groups comprising 1 ,2,2,6,6-pentamethyl-piperidin-4-yl groups.
  • suitable polymerizable stabilizers are disclosed in WO 2015/024865 A1 , page 22, lines 9 to 19.
  • the stabilizer is a (meth)acrylic acid ester of 1 ,2,2,6,6-pentamethyl-4-piperidinol.
  • the amount of polymerizable stabilizers -if present- may be from 0.01 to 2% by weight, based on the sum total of all the monomers in the aqueous monomer solution, preferably from 0.02 % to 1 % by weight, more preferably from 0.05 % to 0.5 % by weight.
  • the aqueous monomer solution comprises at least one non- polymerizable surfactant. Adding such surfactants in particular is advisable when associative monomers are used. For such kind of polyacrylamides, the surfactants lead to a distinct improvement of the product properties. Examples of suitable surfactants including preferred amounts have been disclosed in WO 2015/158517 A1 , page 19, line, 23 to page 20, line 27. If present, such non-polymerizable surfactant may be used in an amount of 0.1 to 5% by weight, for example 0.5 to 3 % by weight based on the amount of all the monomers used.
  • aqueous monomer solution basically any kind of equipment suitable for mixing monomers may be used for example a stirred vessel.
  • the preparation of the aqueous monomer solution is performed in a relocatable monomer make-up unit.
  • a relocatable monomer make-up unit is similar to the relocatable bioconversion unit as described above. Using largely the same equipment for storing acrylonitrile or other monomers, the bioconversion step and for monomer make-up contributes to an economic process for manufacturing aqueous acrylamide solutions.
  • the monomer make-up unit comprises a monomer make-up vessel in which the monomers, water and optionally further components are mixed.
  • the volume of the monomer make-up vessel is not specifically limited and may range from 10 m 3 to 150 m 3 , for example it may be about 20 to 90 m 3 .
  • the monomer make-up vessel may be single walled or double walled and it may be horizontal or vertical.
  • the monomer make-up unit furthermore comprises means for controlling the temperature of the aqueous monomer solution. Usually, the temperature of the aqueous monomer solution should be not more than 25°C.
  • the monomer make-up unit furthermore comprises means for measurement and control.
  • the monomer make-up unit comprises an external
  • temperature control cycle comprising a pump which pumps the aqueous reactor contents from the storage vessel through a heat exchanger and back into the storage vessel, preferably via an injection nozzle.
  • the temperature control cycle may be a separate, relocatable temperature control unit comprising pump and heat exchanger and which is connected with the monomer make-up vessel by pipes or flexible tubes.
  • the temperature control cycle may be integrated into relocatable storage unit. It may -for example- be located at one end of the unit besides the monomer make-up vessel.
  • the monomer make-up vessel may be equipped with a stirrer for mixing the components of the aqueous monomer solution with each other.
  • the external temperature control cycle may be used as means for mixing.
  • the stream of the aqueous monomer mixture which passes through the temperature control cycle and which is injected back into the monomer make-up vessel causes a circulation of the aqueous reaction mixture within the reaction vessel which is sufficient to mix the aqueous reaction mixture.
  • FIG 4 represents a schematically one embodiment of the relocatable monomer make-up unit.
  • the monomer make-up unit comprises a frame (20), a double-walled monomer make-up vessel mounted into the frame comprising an outer wall (21 ) and an inner wall (22).
  • the monomer make-up vessel is self- supporting and a frame is not necessary.
  • the monomer make-up vessel is filled with the monomer mixture.
  • the monomer make-up unit furthermore comprises an external temperature control cycle comprising at least a pump (23) and a temperature control unit (24).
  • the monomer mixture is circulated by means of a pump (23) from the storage vessel to the temperature control unit (24) and is injected back into the storage vessel, preferably via an injection nozzle (25).
  • the monomers may be added directly into the storage vessel or into the temperature control cycle (26) as indicated in Figure 4.
  • the stream of monomer mixture injected back into the monomer make-up vessel causes a circulation of the monomer mixture in the storage vessel which ensures sufficient mixing of the contents of the monomer mixture.
  • a separate temperature control cycle may be used.
  • the monomers to be mixed with each other and with water are preferably mixed in the monomer make-up vessel, however in another embodiment, it is possible to add the monomers into the temperature control cycle. It is frequently advisable, to first add water to the monomer make-up vessel and then one or more further monomers and/or acids or bases and/or further additives. If acidic monomers such as acrylic acid are used, they should be neutralized before adding acrylamide. For copolymers comprising acrylic acid and acrylamide at first the necessary amount of water may be added into the vessel, followed by NaOH, thereafter acrylic acid and thereafter acrylamide.
  • additives which optionally might be present such as complexing agents, defoamers, surfactants, or stabilizers as mentioned above may be dissolved in aqueous solvents, preferably water in suitable dissolution units and the solutions also added into the monomer make-up vessel.
  • the bioconversion unit may also be used for monomer make-up.
  • the aqueous acrylamide solution does no longer comprise the biocatalyst.
  • the acyl amide solution still comprises the biomass.
  • the biocatalyst may be removed after preparing the aqueous monomer solution in the same manner as described above or it may not be removed. Criteria for deciding in which cases it may not be necessary to remove the biocatalyst have already been mentioned above.
  • the aqueous monomer solution After mixing the aqueous monomer solution it is transferred from the monomer make- up vessel (or any other vessel serving as monomer make-up vessel such as the bioconversion unit) to the polymerization unit.
  • step [2] the aqueous monomer solution prepared in step [1] is inerted and polymerized in the presence of suitable initiators for radical polymerization, thereby obtaining an aqueous polyacrylamide concentrate as defined above.
  • Step [2] is carried out at location A.
  • the polymerization technique to be used for radical polymerization basically depends on the concentrations of the monomers in the aqueous monomer solution. For lower concentrations, for example a monomer concentration from 1 % by weight to about 8 % by weight, solution polymerization may be chosen. For higher concentrations, for example a monomer concentration from about 8 % by weight to 14.9 % by weight, adiabatic gel polymerization may be chosen. However, the invention is not limited to the two polymerization techniques. Also, other polymerization techniques suitable for radically polymerizing aqueous solutions of ethylenically unsaturated monomers may be used.
  • the aqueous monomer solution prepared in course of step [1] is inerted and polymerized in the presence of suitable initiators for radical polymerization thereby obtaining an aqueous solution of polyacrylamides.
  • the polymerization unit for solution polymerization comprises means for mixing the contents of the polymerization unit and means for heating the contents of the polymerization unit.
  • the polymerization unit may for example comprise a polymerization vessel mounted in a frame or on a truck. Heating the contents of the polymerization unit may be carried out by using a polymerization unit comprising a heatable jacket. In other embodiment, the polymerization may comprise an external heating cycle or heating elements in the reactor. Mixing may be carried out for example by means of a stirrer.
  • the polymerization is performed in the presence of suitable initiators for radical polymerization.
  • suitable initiators for radical polymerization are known to the skilled artisan.
  • suitable initiators comprise water-soluble azo initiators.
  • the azo initiators are preferably fully water-soluble, but it is sufficient that they are soluble in the monomer solution in the desired amount.
  • azo initiators having a 10 h ti /2 in water of 40°C to 70°C may be used.
  • the 10-hour half-life temperature of azo initiators is a parameter known in the art. It describes the temperature at which, after 10 h in each case, half of the amount of initiator originally present has decomposed.
  • Suitable azo initiators having a 10 h ti /2 temperature between 40 and 70°C include 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (10 h ti /2 (water): 44°C), 2,2'-azobis(2-methylpropionamidine) dihydrochloride (10 h ti /2 (water): 56°C), 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine hydrate (10 h ti /2 (water): 57°C), 2,2'-azobis ⁇ 2-[1 -(2-hydroxyethyl)-2-imidazolin-2-yl]propane ⁇
  • the initiators preferably are added as aqueous solutions to the aqueous monomer solution.
  • the initiator raw material may be stored at location A in a cold storage container.
  • Dissolving the initiators in water may be performed using suitable initiator make-up vessels.
  • the initiator make-up vessel may comprise a temperature control cycle. Instead of an own temperature control cycle, cold water, for example water having a temperature of less than +5°C may be used for dissolving the initiators.
  • the initiator make-up vessels furthermore may comprise means for mixing such as a stirrer. However, mixing may also be conducted by bubbling an inert gas through the aqueous mixture thereby simultaneously mixing and inerting the aqueous mixture.
  • the solutions may be filtered before use.
  • the aqueous monomer solution is filled into the polymerization unit.
  • the aqueous monomer solution and the reactor may already be inerted or the aqueous monomer solution may become inerted after adding it into the reactor, for example by injecting an inert gas into the reactor while mixing.
  • the desired starting temperature for polymerization may be adjusted and the initiators added.
  • the initiators may be added all at once before polymerization or added over time.
  • the temperature may be kept constant in course of polymerization or a temperature profile may be used, for example the temperature may be increased stepwise.
  • the temperature for polymerization may be selected by the skilled artisan. In certain embodiments of the invention, temperatures from 40°C to 70°C may be selected.
  • Solution polymerization in particular is suitable for lower monomer concentrations, such as a monomer concentration in the aqueous monomer solution from 1 % by weight to about 8 % by weight, for example from 2 % by weight to 7 % by weight or from 3 % by weight to 6 % by weight.
  • the aqueous polyacrylamide composition made by solution polymerization may be removed from the polymerization unit through an opening, for example simply by means of gravity.
  • the removal may be supported by pumping and/or by pressurizing the polymerization, for example by injecting an inert gas.
  • the aqueous monomer solution prepared in course of step [1] is inerted and polymerized in the presence of suitable initiators for radical polymerization under adiabatic conditions.
  • the polymerization of the aqueous monomer solution generates polymerization heat. Due to the adiabatic reaction conditions, the temperature of the polymerization mixture increases in course of polymerization because polymerization heat is generated.
  • Such a polymerization technique is also briefly denominated by the skilled artisan as“adiabatic gel polymerization”. Reactors for adiabatic gel polymerization are unstirred. Due to the relatively high monomer concentration the aqueous monomer solution used solidifies in course of polymerization thereby yielding an aqueous polymer gel.
  • the term“polymer gel” has been defined for instance by L. Z. Rogovina et al., Polymer Science, Ser. C, 2008, Vol. 50, No. 1 , pp. 85-92. “Adiabatic” is understood by the person skilled in the art to mean that there is no exchange of heat with the environment. This ideal is naturally difficult to achieve in practical chemical engineering.
  • “adiabatic” shall consequently be understood to mean“essentially adiabatic”, meaning that the reactor is not supplied with any heat from the outside during the polymerization, i.e. is not heated, and the reactor is not cooled during the polymerization.
  • the reactor is not supplied with any heat from the outside during the polymerization, i.e. is not heated, and the reactor is not cooled during the polymerization.
  • certain amounts of heat can be released or absorbed via the reactor wall because of temperature gradients, but this effect naturally plays an ever lesser role with increasing reactor size.
  • the concentration of the polyacrylamides in the aqueous polyacrylamide gel obtained corresponds to the monomer concentration in the monomer solution.
  • adiabatic gel polymerization in particular is suitable for higher monomer concentration, such as a monomer concentration from about 8 % by weight to 14.9 % by weight, for example a monomer concentration from about 10 % by weight to 14.9 % by weight or 12 % by weight to 14.9 % by weight.
  • the kind of polymerization unit is not limited. Suitable are relocatable vessels, for examples containerized vessels, vessels mounted of a truck or vessels comprising legs or other kinds of support which permit deploying the polymerization unit at location A.
  • the polymerization unit preferably has a volume of more than 1 m 3 , for example from 1 m 3 to 200 m 3 .
  • the polymerization may be carried out in a transportable polymerization unit having a volume of 1 m 3 to 40 m 3 , in particular 1 to 30 m 3 , preferably from 5 m 3 to 40 m 3 , and more preferably 20 m 3 to 30 m 3 .
  • transportable polymerization unit may be transported for instance by trucks or railcars. Polymerization units having such a volume can easily be transported by trucks, railcars or ships when filled with aqueous polyacrylamide concentrate.
  • larger polymerization units may be used, for example polymerization unit having a volume from 100 m 3 to 200 m 3 , or from 120 m 3 to 160 m 3 .
  • polymerization can still be transported as a whole when empty, however, it is difficult to transport them by railcars or trucks when filled with aqueous polyacrylamide concentrate.
  • the polymerization unit may be of cylindrical or conical shape.
  • the polymerization unit is cylindrical having a conical taper at the bottom and a bottom opening for removing the aqueous poly acrylamide gel.
  • the inner wall of the transportable polymerization unit may preferably be coated with an anti-adhesive coating.
  • anti-adhesive coatings are known in the art. Examples comprise polypropylene, polyethylene, epoxy resins and fluorine containing polymers such as
  • the polymerization unit P1 comprises a cylindrical upper part (30) and a conical part (31 ) at its lower end. At the lower end, there is a bottom opening (32) which may be opened and closed. After polymerization, the polyacrylamide gel formed is removed through the opening (32). It furthermore comprises means (33) such as legs or similar elements allowing to deploy the polymerization unit in a vertical manner.
  • the polymerization unit is a unit which may be transported also when filled with aqueous polyacrylamide gel.
  • the diameter (D) of such a polymerization unit in the cylindrical section may in particular be from 1.5 to 2.5 m, preferably from 2 m to 2.5 m and the length (L) of the cylindrical section may be from 4 to 6 m, preferably 5 to 6 m.
  • the conus angle a in the conical part may be from 15° to 90°, preferably from 20° to 40°.
  • the volume of the transportable polymerization unit P1 described herein may preferably be from 20 m 3 to 30 m 3 .
  • the transportable polymerization unit P1 comprises one or more feeds for the aqueous monomer solution, initiator solutions, gases such as nitrogen or other additives.
  • the inner wall of the transportable polymerization unit P1 may be coated with an anti-adhesive coating.
  • the diameter of the bottom opening (32) may for example be from 0.2 to 0.8 m, in particular from 0.4 to 0.7 m, preferably from 0.5 to 0.7 m.
  • the transportable polymerization unit P1 is operated in a vertical position as depicted in Figure 5.
  • it may preferably be tilted to a horizontal position.
  • the transport in horizontal position on a truck is schematically shown in Figure 6.
  • polymerization units having basically the same shape, i.e. a cylindrical upper part and a conical part at its lower end and a bottom opening, however having a volume from 100 m 3 to 200 m 3 , or from 120 m 3 to 160 m 3 , a diameter from about 3 m to 4.5 m, wherein the length of the cylindrical section is from 10 m to 12 m and the length of the concial section is from 1.5 to 2.5 m.
  • the aqueous monomer solution prepared in course of step [1] is filled into the polymerization unit.
  • the monomer make-up vessel (or any other vessel serving as monomer make-up vessel such as the bioconversion unit) is connected with the polymerization unit by a monomer feed line.
  • the polymerization is performed in the presence of suitable initiators for radical polymerization.
  • suitable azo initiators have already been mentioned above.
  • redox initiators may be used for initiating. Redox initiators can initiate a free-radical polymerization already at low temperatures.
  • redox initiators include systems based on Fe 2+ /Fe 3+ - H2O2, Fe 2+ /Fe 3+ - alkyl hydroperoxides, alkyl hydroperoxides - sulfite, for example t-butyl hydroperoxide - sodium sulfite, peroxides - thiosulfate or alkyl hydroperoxides - sulfinates, for example alkyl hydroperoxides/ hydroxymethane-sulfinates, for example t-butyl hydroperoxide - sodium hydroxymethanesulfinate.
  • mixtures of initiators for example mixtures of two different azo initiators or mixtures of azo initiators and redox initiators may be used.
  • the initiators preferably are added as aqueous solutions to the aqueous monomer solution, for example into the monomer feed line or directly into the polymerization unit.
  • inertization is performed in the polymerization unit.
  • inert gases such as nitrogen or argon are injected into the reactor filled with the monomer solution.
  • nozzles for injecting inert gases are located in the bottom of the polymerization unit.
  • the polymerization unit P1 they may for example be located in the conical taper.
  • the bubbles of inert gases rising in the reactor remove oxygen and simultaneously mix the contents of the reactor very efficiently.
  • Initiator solutions metered into the reactor are mixed with the aqueous solution by means of the inert gas injection.
  • inertization may be performed in the monomer feed line.
  • Inert gases such as nitrogen or argon may be injected into the feed line.
  • the monomer feed line additionally comprises a static mixture.
  • the gas injected into the monomer feed line may be removed before entering into the reactor by means of a suitable degassing unit such as the degassing units described in WO 2003/066190 A1 or in CN 202492486 U.
  • no separate degassing unit is used, but the solution is degassed after entering into the polymerization unit.
  • the monomer solution enters into the reactor by means of a spray nozzle for the purpose of removing gas.
  • the radical polymerization starts after adding the initiator solutions, preferably solutions of redox initiators, to the aqueous monomer solution thereby forming an aqueous polyacrylamide gel. Due to the polymerization heat generated in course of
  • the temperature of the aqueous monomer solution before the onset of polymerization shall be denominated as Ti and the temperature of the aqueous polymer gel directly after polymerization shall be denominated as T 2 . It goes without saying that T 2 > Ti.
  • the temperature T 2 reached in course of polymerization is not influenced by external heating or cooling but only depends on the polymerization parameters chosen. But suitable choice of the polymerization parameters, the skilled artisan can adjust T 2 .
  • the temperature increase in course of polymerization basically depends on the heat of polymerization generated in course of polymerization, the heat capacity of contents of the polymerization unit and the temperature T 1 of the monomer solution, i.e. the temperature before the onset of polymerization. Due to high water contents of the mixture for polymerization the heat capacity of the mixture for polymerization is dominated by the heat capacity of water and it may of course be measured.
  • the polymerization heat per mole (or per mass) for common monoethylenically unsaturated monomers is known in the art and may therefore be gathered from the scientific literature. Of course, it may also be measured. So, it is possible for the skilled artisan to calculate at least roughly the heat of polymerization for specific monomer compositions and specific monomer concentrations. The higher the concentration of the
  • the temperature T 2 should be at least 45°C, preferably at least 50°C, for example from 50°C to 70°C.
  • Ti should be at least about 25°C, for example from 25°C to 40°C.
  • the temperature Ti of the monomer solution may be adjusted as already disclosed above, i.e. already the temperature of the monomer solution in the monomer make-up vessel may be controlled appropriately.
  • a temperature control unit for adjusting Ti may be located in the monomer feed line, or the polymerization unit may be connected to a temperature control unit before polymerization.
  • Ti is in the range from 25°C to 40°C and T 2 is in the range from 50°C to 65°C.
  • the time of polymerization may be from 2 to 24 h, for example from 3 to 6 h.
  • the polymerization may comprise additional steps.
  • the polymerization comprises an after-treatment step aiming at increasing the molecular weight of the aqueous polyacrylamide concentrate obtained.
  • such after-treatment is carried out by heat- treating the aqueous polyacrylamide concentrate obtained from solution polymerization or from adiabatic gel polymerization as described above.
  • Such a step preferably is carried out under nitrogen or other inert gases.
  • the aqueous polyacrylamide concentrate obtained from solution polymerization or from adiabatic gel polymerization as described above.
  • Such a step preferably is carried out under nitrogen or other inert gases.
  • polyacrylamide may be pumped through a heat exchanger, a heated static mixer or a heated progressive cavity pump.
  • step [3] the aqueous polyacrylamide concentrate is transported from location A to a different location B.
  • the step may be carried out, by either transferring the polyacrylamide concentrate into a suitable transport unit for transport and transporting the transport unit filled with aqueous polyacrylamide concentrate from location A to a location B or by transporting the polymerization unit filled with aqueous polyacrylamide concentrate from location A to a location B.
  • the aqueous polyacrylamide concentrate is removed from the polymerization unit and transferred to a suitable transport unit, for example by pumping.
  • Suitable transport units may have a volume from 1 m 3 to 40 m 3 , in particular from 5 m 3 to 40 m 3 , preferably from 10 to 30 m 3 , for example 20 m 3 to 30 m 3 , or from 15 m 3 to 25 m 3 .
  • suitable transport units comprise vessels comprising at least one opening such as tank containers. The transport may be carried out by any transport means suitable for transporting the transport unit, for example by trucks, railcars or ships.
  • transport unit shall include separate transport units such as vessels, containers, for example ISO containers or intermediate bulk containers, which are loaded on suitable transport means for transport, for example on trailers, container cars or ships.
  • the transport means may transport one single transport unit or a plurality of transport units.
  • transport unit furthermore includes transport units in which the transport compartment is permanently fixed on the transport means, such as for example tank trucks or tanks cars.
  • the transport is carried out by trucks.
  • the transport unit may also be fixed on a truck.
  • the transport unit may be an ISO tank container. Typical dimensions of ISO containers have already been mentioned above.
  • tanks fixed on a truck may be used.
  • the tank comprises an outlet opening at the rear end of the truck and for supporting removal of the contents the tank may be tilted.
  • the tank comprises an outlet opening at the bottom side of the tank.
  • the tank may comprise a conus at the bottom side of the tank and the outlet opening in located at the lower end of the conus.
  • the polymerization unit itself filled with the aqueous polyacrylamide concentrate is transported from location A to location B.
  • Suitable transportable polymerization units may have a volume from 1 m 3 to 40 m 3 , in particular 5 m 3 to 40 m 3 , preferably from 10 to 30 m 3 , for example 20 m 3 to 30 m 3 .
  • the he cylindrical transportable polymerization unit P1 is in particular suitable for transport. It is operated in a vertical position for polymerization and removal of the aqueous polymer concentrate. For transport, it may preferably be tilted to a horizontal position.
  • the transport in horizontal position on a truck is schematically shown in Figure 6.
  • the truck comprises means for loading the polymerization unit P1 onto it in horizontal position and for unloading and deploying the polymerization unit in vertical position.
  • additional means for example cranes, for loading at location A and unloading at location B are not necessary.
  • means for loading and unloading the transportable polymerization unit may be provided at locations A and B.
  • the truck or any other transport device does not need means for loading and unloading.
  • the method of transport may be selected by the skilled artisan.
  • the first method of using a separate transport unit may in particular be advisable when the polymerization is performed by solution polymerization, because the reactor for solution polymerization is more complicated than a reactor for adiabatic gel polymerization.
  • the transport time i.e. the time for transporting the transport unit or the polymerization unit filled with aqueous polyacrylamide concentrate form location A to location B may be very different, depending on the distance between the locations A and B. It may range from minutes to several days, for example from 1 h to 7 days, in particular from 2 hours to 3 days.
  • Step [4] is performed at location B.
  • the aqueous polyacrylamide gel is removed from the transportable polymerization unit and/or a transport unit.
  • removing the aqueous polyacrylamide concentrate may be carried out by any kind of technology.
  • the details depend on the specific design of the transport unit, the kind of concentrate, in particular its viscosity, and the connected downstream processing equipment.
  • the aqueous polyacrylamide concentrate may be removed by means of a pump. Removal may be supported by applying pressure onto the transport unit, in particular by means of gas pressure. Furthermore, removal may also be supported -depending on the construction of the transport units- by tilting the transport unit.
  • aqueous polyacrylamide concentrate as such, i.e. it is transferred directly from the transport unit of from a storage unit to the application where it is used. Examples of applications in which concentrates may be used directly, will be mentioned below.
  • the transfer of the aqueous polyacrylamide concentrate may be affected by means of piping or other suitable conduit.
  • the aqueous polyacrylamide concentrate may be further diluted for application using an aqueous liquid as defined above.
  • aqueous polyacrylamide solution a composition resulting from such additional dilution step shall be referred to as “aqueous polyacrylamide solution”.
  • an additional dilution step may be carried out in any kind of dilution device.
  • a dilution of the aqueous polyacrylamide concentrate is conducted in a relocatable dissolution unit.
  • the aqueous polyacrylamide concentrate may be pumped into the dilution unit.
  • the aqueous polyacrylamide concentrate may optionally be mixed with further components. The skilled artisan may choose such further components according to his/her needs.
  • Examples of dilution devices comprise static mixers, combination of static mixers with further mixing equipment such as a combination of static mixers with unstirred vessels or in-line dispersing such as rotor-stator units or stirred vessels.
  • Locations A and B each comprise a central process measuring and control technology unit.
  • the process measuring and control technology unit is a relocatable unit.
  • the process measuring and control technology unit at location A is connected with all units at location A and also preferably, the process measuring and control technology unit at location B is connected with all units at location B, thereby enabling a central process control similar to fixed plants.
  • all connections with measuring and control instruments of a certain unit, e.g. the dissolution unit, the monomer storage units or the polymerization units are bundled in one cable, for example BUS
  • the present invention relates to a modular, relocatable plant for manufacturing aqueous polyacrylamide concentrates by polymerizing an aqueous solution comprising at least acrylamide thereby obtaining an aqueous polyacrylamide gel, comprising at least
  • a relocatable monomer make-up unit for preparing an aqueous monomer solution comprising at least water and acrylamide
  • o means for removing the aqueous polyacrylamide concentrate from the polymerization unit and/or the transport unit.
  • the modular, relocatable plant comprises relocatable storage units for water-soluble, monoethylenically unsaturated monomers different from acrylamide.
  • acrylamide is also manufactured at location A by hydrolyzing acrylonitrile in water in the presence of a biocatalyst capable of converting acrylonitrile to acrylamide.
  • aqueous polyacrylamide gels manufactured according to the present invention may be used for various purposes, for example for mining applications, oilfield applications, water treatment, waste water cleanup, paper making or agricultural applications.
  • aqueous polyacrylamide gels may be used as such or they may be formulated with further components.
  • the specific composition of aqueous polyacrylamide solutions is selected by the skilled artisan according to the intended use of the polyacrylamide solution.
  • Examples of oilfield applications in which the aqueous polyacrylamide solutions manufactured according to the present invention may be used include enhanced oil recovery, hydraulic fracturing or oil well drilling.
  • the aqueous polyacrylamide solutions in one embodiment, the aqueous polyacrylamide solutions
  • the present invention also relates to the use of aqueous polyacrylamide concentrates in a process of enhanced oil recovery comprising at least the following steps:
  • the aqueous injection fluid may comprise further components.
  • further components include biocides, stabilizers, free-radical scavengers, initiators, surfactants, cosolvents, bases and complexing agents.
  • the concentration of the polyacrylamide in the injection fluid is from 0.1 % to 2 % by weight based on the total sum of all the components in the aqueous formulation.
  • the amount is preferably from 0.1 % to 1 % by weight, for example from 0.2 % to 0.8% by weight. It goes without saying, that the concentration of the polyacrylamide in the aqueous polyacrylamide concentrate needs to be higher than the polyacrylamide concentration in the aqueous injection fluid.
  • At least one production well and at least one injection well are sunk into the mineral oil deposit.
  • a deposit will be provided with a plurality of injection wells and with a plurality of production wells.
  • the mineral oil flows in the direction of the production well and is produced through the production well.
  • the term“mineral oil” does not of course just mean a single-phase oil; instead, the term also encompasses the customary crude oil-water emulsions.
  • the aqueous fluid for injection can be made up in freshwater or else in water comprising salts, such as seawater or formation water.
  • polyacrylamide concentrate made by diabatic gel polymerization may be used, preferably, by adiabatic gel polymerization of an aqueous monomer solution having a monomer concentration of 12 % to 14.9 % by weight.
  • the concentration of the copolymer in the injection fluid is fixed such that the aqueous formulation has the desired viscosity for the end use.
  • the viscosity of the formulation should generally be at least 5 mPas (measured at 25°C and a shear rate of 7 s 1 ), preferably at least 10 mPas.
  • Hydraulic fracturing involves injecting fracturing fluid through a wellbore and into a formation under sufficiently high pressure to create fractures, thereby providing channels through which formation fluids such as oil, gas or water, can flow into the wellbore and thereafter be withdrawn.
  • Fracturing fluids are designed to enable the initiation or extension of fractures and the simultaneous transport of suspended proppant into the fracture to keep the fracture open when the pressure is released.
  • Said effect can be achieved by using a thickened fluid having a high viscosity.
  • the aqueous polyacrylamide concentrates manufactured according to the present invention serve as viscosifiers in hydraulic fracturing applications.
  • the present invention also relates to the use of aqueous polyacrylamide concentrates as viscosifier in a process for fracturing subterranean formations comprising at least the following steps:
  • an aqueous fracturing fluid by mixing at least an aqueous base fluid, an aqueous polyacrylamide concentrate having a concentration of 1.0 to 14.9 % by weight of polyacrylamides, relating to the total of all components of the aqueous polyacrylamide concentrate,
  • aqueous polyacrylamide concentrate is prepared by the process as described above, and
  • aqueous fracturing fluid additionally comprises a proppant.
  • the aqueous base fluid may be freshwater or water comprising salts, such as seawater or formation water or produced water.
  • Suitable proppants comprise naturally-occurring sand grains, resin-coated sand, sintered bauxite, glass beads or ultra-lightweight polymer beads. Details about the polyacrylamides have already been detailed above.
  • the concentration of the polyacrylamides in the aqueous fracturing fluid here is such, that they significantly increase the viscosity of the aqueous fracturing fluid, thereby enabling proppant transport and preventing settling of the proppants.
  • the concentration may be in the range from 1 ,000 ppm to 10,000 ppm, for example from 2,000 ppm to 7,500 ppm of polyacrylamides relating to the total of all components of the aqueous fracturing fluid except the proppants.
  • the amount of the aqueous polyacrylamide concentrate is selected accordingly.
  • Fracturing fluids may be mixed using so-called blenders (often mounted on trucks), in which an aqueous base fluid, proppants, friction reducers and optionally further components are mixed.
  • blenders often mounted on trucks
  • an aqueous base fluid, proppants, the aqueous polyacrylamide concentrate as described above and optionally further components are mixed with each other by means of a customary blender thereby obtaining an aqueous fracturing fluid.
  • the concentration of proppants in the fracturing fluid may be constant in course of the fracturing process. In other embodiments, the concentration of proppants in the fracturing fluid may be varied in course of the fracturing process. In one
  • the fracturing process may start with injection of a certain amount of fracturing fluid which does not comprise any proppants and proppants are added to the fracturing fluid only at a later stage of the fracturing process.
  • the aqueous polyacrylamide concentrates manufactured according to the present invention serve as friction reducers in slickwater fracturing applications.
  • Such fluids mainly comprise water.
  • the pumping rates and the pressures used are significantly higher than for high-viscosity fluids.
  • the high flow ensures proppant transport.
  • the turbulent flow of the fracking fluid causes significant energy loss due to friction.
  • friction reducers for example high molecular weight polyacrylamides may be used which change turbulent flow to laminar flow.
  • the present invention also relates to the use of aqueous polyacrylamide concentrates as friction reducer in a process for fracturing subterranean formations comprising at least the following steps:
  • an aqueous fracturing fluid by mixing at least an aqueous base fluid, an aqueous polyacrylamide concentrate having a concentration of 1.0 to 14.9 % by weight of polyacrylamides, relating to the total of all components of the aqueous polyacrylamide concentrate,
  • aqueous polyacrylamide concentrate is prepared by the process as described above, and
  • aqueous fracturing fluid additionally comprises a proppant.
  • the concentration of the polyacrylamide friction reducer in the aqueous fracturing fluid is selected by the skilled artisan according to his/her needs. Usually, it is in the range from 20 ppm to 600 ppm, in particular from 20 ppm to 300 ppm, for example from 125 ppm to 250 ppm of polyacrylamides relating to the total of all components of the aqueous fracturing fluid except the proppants.
  • polyacrylamide concentrates for making the aqueous fracturing fluid is selected accordingly.
  • an aqueous polyacrylamide concentrate made by adiabatic gel polymerization may be used, preferably, by adiabatic gel polymerization of an aqueous monomer solution having a monomer concentration of 12 % to 14.9 % by weight.
  • the method for preparing an aqueous polyacrylamide solution according to the present invention is carried out in areas where mining, mineral processing and/or metallurgy activities takes place. Consequently, the aqueous polyacrylamide solution as product obtained by the method of the present invention is preferably used for applications in the field of mining, mineral processing and/or metallurgy and the method for preparing the aqueous polyacrylamide solution is preferably used at the plant of the respective industry.
  • mining activities comprises extraction of valuable minerals or other geological materials from certain deposits.
  • deposits can contain ores, for example metal containing ores, sulfidic ores and/or non-sulfidic ores.
  • the ores may comprise metals, coal, gemstones, limestone or other mineral material.
  • Mining is generally required to obtain any material in particular mineral material that cannot be grown through agricultural processes or created artificially in a laboratory or factory.
  • the aqueous polyacrylamide solution according to the present invention is preferably used to facilitate the recovery of mineral material, for beneficiation of ores and for further processing of ores to obtain the desired minerals or metals.
  • mining industries, mineral processing industries and/or metallurgy industries are active in the processing of ores and in the production of for example alumina, coal, iron, steel, base metals, precious metals, diamonds, non-metallic minerals and/or areas where aggregates play an important role.
  • the method of the present invention and the obtained homo- or copolymer of acrylamide can be used for example at plants for alumina production, where alumina is extracted from the mineral bauxite using the Bayer caustic leach process,
  • the present invention relates to the use of an aqueous polyacrylamide solution for mining, mineral processing and/or metallurgy activities comprising the use for solid liquid separation, for tailings disposal, for polymer modified tailings deposition, for tailings management, as density and/or rheology modifier, as agglomeration aid, as binder and/or for material handling, wherein the aqueous polyacrylamide solution is prepared at the plant of the respective industry, comprising for example the following steps: hydrolyzing acrylonitrile in water in presence of a biocatalyst capable of converting acrylonitrile to acrylamide so as to obtain an acrylamide solution, polymerizing the acrylamide solution so as to obtain a polyacrylamide gel, and dissolving the polyacrylamide gel by addition of water so as to obtain an aqueous polyacrylamide solution.
  • a homopolymer of acrylamide for example can be used. Further preferred are also copolymers of acrylamide. Such copolymers of acrylamide can be anionic, cationic or non-ionic. Anionic copolymers are for example co-polymers of acrylamide with increasing proportions of acrylate groups, which give the polymers negative charges, and thus anionic active character, in aqueous solution. Anionic copolymers of acrylamide can in particular be used for waste water treatment in metallurgy like iron ore plants, steel plants, plants for electroplating, for coal washing or as flocculants.
  • Non-ionic polymers and/or copolymers of acrylamide can be used for example as nonionic flocculants suitable as settlement aids in many different mineral processing applications and are particularly effective under very low pH conditions, as encountered for example in acidic leach operations.
  • Cationic copolymers of acrylamide have in particular an increasing proportion of cationic monomers. The cationic groups, which are thus introduced into the polymer, have positive charges in aqueous solution.
  • the polymer obtained from the method of the present invention is used as flocculant in a process in which individual particles of a suspension form aggregates.
  • the polymeric materials of the present invention forms for example bridges between individual particles in the way that segments of the polymer chain adsorb on different particles and help particles to aggregate. Consequently, the polymers of the present invention act as agglomeration aid, which may be a flocculant that carries active groups with a charge and which may counterbalance the charge of the individual particles of a suspension.
  • the polymeric flocculant may also adsorb on particles and may cause destabilization either by bridging or by charge neutralization.
  • the polymer in case the polymer is an anionic flocculant, it may react against a positively charged suspension (positive zeta potential) in presence of salts and metallic hydroxides as suspension particles, for example.
  • the polymer of the present invention is for example a cationic flocculant, it may react against a negatively charged suspension (negative zeta potential) like in presence of for example silica or organic substances as suspension particles.
  • the polymer obtained from the method of the present invention may be an anionic flocculant that agglomerates clays which are electronegative.
  • the method of the present invention and the obtained polymer and/or copolymer of acrylamide is used for example in the Bayer process for alumina production.
  • the polyacrylamide can be used as flocculant in the first step of the Bayer-Process, where the aluminum ore (bauxite) is washed with NaOH and soluble sodium aluminate as well as red mud is obtained.
  • the flocculation of red mud is enhanced and a faster settling rate is achieved when acrylamide polymers and/or co-polymers are added.
  • polyacrylamide may be used for settling aluminum red mud slurries in alumina plants, provides high settling rates, offers better separation performance and reduces suspended solids significantly. Also, the liquor filtration operations are improved and with that the processing is made economically more efficient. It is further preferred that the polyacrylamides are used in decanters, in washers, for hydrate thickening, for green liquor filtration, as crystal growth modifiers, as thickener and/or as rheology modifier.
  • the method of the present invention and the polymers of acrylamide are used in processes for solid liquid separation as for example flocculant or dewatering aid, which facilitate thickening, clarifying, filtration and centrifugation in order to enhance settling rates, to improve clarities and to reduce underflow volumes.
  • the polyacrylamide homo- or co-polymer of the present invention increase filtration rates and yields, as well as reducing cake moisture contents.
  • the use of the method and the obtained polyacrylamide of the present invention in particular for material handling and as binder.
  • the typical rock and/or ore processing for example starts with ore extraction, followed by crushing and grinding the ore, subsequent mineral processing (processing or the desired/valuable mineral material), then for example metal production and finally the disposal of waste material or tailings.
  • the handling of the mineral material can be enhanced by increasing efficiency and yield, by improving product quality and by minimizing operating costs.
  • the present invention can be used for a safer working environment at the mine site and for reduction of environmental discharges.
  • the method and the obtained polyacrylamide of the present invention can for example be used as thickener, as density and/or rheology modifier, for tailings management.
  • the obtained polyacrylamide polymer can modify the behavior of the tailings for example by rheological adjustment.
  • the obtained polyacrylamide polymers are able to rigidify tailings at the point of disposal by initiating instantaneous water release from the treated slurry. This accelerates the drying time of the tailings, results in a smaller tailings footprint and allows the released water to be returned to the process faster. This treatment is effective in improving tailings properties in industries producing alumina, nickel, gold, iron ore, mineral sands, oil sands or copper for example.
  • the polymers obtained according to the present invention are for example maximized life of disposal area, slurry placement control, no re- working of deposit required, co-disposal of coarse and fine material, faster trafficable surface, reduced evaporative losses, increased volume for recycling, removed fines contamination, reduced fresh water requirement, lower land management cost, less mobile equipment, lower rehabilitation costs, quicker rehabilitation time, lower energy consumption, accelerated and increased overall water release, improved rate of consolidation, reduced rate of rise, reduced amount of post depositional settlement.
  • the obtained product from the method of the present invention is used for agglomeration of fine particulate matter and for the suppression of dust.
  • polyacrylamide polymers or copolymers are used as organic binders to agglomerate a wide variety of mineral substrates.
  • the polyacrylamide polymers or copolymers are used for iron ore pelletization as a full or partial replacement for bentonite.
  • the product from the method of the present invention can be used as binder, in particular as solid and liquid organic binders in briquetting, extrusion, pelletization, spheronization and/or granulation applications and gives for example excellent lubrication, molding and/or binding properties for processes such as coal-fines briquetting, carbon extrusion, graphite extrusion and/or nickel briquetting.
  • the method of the present invention and in particular the aqueous polyacrylamide solution obtained by the method is used for the beneficiation of ores which comprise for example coal, copper, alumina, gold, silver, lead, zinc, phosphate, potassium, nickel, iron, manganese, or other minerals.
  • the process according to the present invention provides significant advantages as compared to known processes for the manufacture of polyacrylamide powders as well as compared to known processes for manufacturing polyacrylamide solutions on-site.
  • drying aqueous polyacrylamide gel thereby obtaining polyacrylamide powders, transporting the powders to the site of use and re-dissolving the dry powders at the site of use is energy extensive and consequently the operational costs for drying are high. Furthermore, also the capital expenditure for the entire post- processing equipment including size reduction, drying, sieving, grinding is significant in relation to the total capital expenditure for the entire plant.
  • the process according to the present invention has the advantage that it is not necessary to move the entire plant when polyacrylamides are no longer needed at a location, i.e. at an oil well, but at another location, i.e. another oil well.
  • the equipment for manufacturing the aqueous polyacrylamide concentrates may remain at location A.
  • location A bundles everything being complicated (e.g. polymerization) and/or having a hazard potential (i.e. storage of potentially hazardous products) and therefore requires personnel experienced with chemical production.
  • Directly using the aqueous polyacrylamide concentrates has the advantage that no equipment for comminution of aqueous polyacrylamide gels is necessary. Examples:
  • the intrinsic viscosity was measured with an automatic Ubbelohde viscosimeter. For the measurement, a 0.5 wt. % solution of the respective gel was prepared with half concentrated pH 7 buffer. The fully hydrated solution was filtered over a 190 pm sieve and further diluted with half concentrated pH 7 buffer to 350 ppm. At 25 °C, viscosity was measured for 5 different concentrations. The intrinsic viscosity value was taken by extrapolation of the trend line.
  • a 0.5 wt. % solution of the respective gel was prepared with half concentrated pH 7 buffer. The fully hydrated solution was filtered over a 190 pm sieve. At 25 °C and a shear rate of 100 s -1 , the viscosity was measured every 10 s for 180 s. The average value was taken as RS viscosity.
  • aqueous polyacrylamide composition was used as it is, without further dilution. Depending on the viscosity different spindles have to be used.
  • the filterability of the polymer solutions was characterized using the MPFR value (Millipore filtration ratio).
  • the MPFR value characterizes the deviation of a polymer solution from ideal filtration characteristics, i.e. when there is no reduction of the filtration rate with increasing filtration. Such a reduction of the filtration rate may result from the blockage of the filter in course of filtration.
  • the MPFR value was calculated by the following formula
  • T x g is the time at which the amount solution specified passed the filter, i.e. tiso g is the time at which 180 g of the polyacrylamide solution passed the filter.
  • API RP 63 Recommended Practices for Evaluation of Polymers Used in Enhanced Oil Recovery Operations”, American Petroleum Institute
  • a 5000 ppm polymer solution in pH 7 buffer is diluted to 1000 ppm with pH 7 buffer.
  • the gel fraction is given as ml. of gel residue on the sieve when 250 g 1000 ppm polymer solution are filtered over 200 pm sieve and consequently washed with 2 I of tab water.
  • Aqueous polyacrylamide concentrate comprising a copolymer comprising 69.4 wt.% (75.0 mol%) of acrylamide and 30.6 wt.% (25 mol%) of sodium acrylate
  • Solid content of 13 % by weight - Synthesis by adiabatic gel polymerization A 1 L beaker with magnetic stirrer, pH meter and thermometer was charged with 45.46 g of sodium acrylate (35% by weight in water), 260 g of distilled water, 69.4 g of acrylamide (52% by weight in water), and 1.2 g of the stabilizer sodium 2-mercapto- benzothiazole (Na-MBT; 50% by weight in water).
  • the monomer solution was adjusted to the initiation temperature of 25 °C.
  • the solution was transferred to a Dewar vessel, the temperature sensor for the temperature recording was inserted, and the flask was purged with nitrogen for 45 minutes.
  • the polymerization was initiated with at 25 °C with 0.25 g of a 10% aqueous solution of 2,2-azobis (2-(2-imidazolin-2-yl) propan) dihydrochlorid (Wako VA 044), 0.05 g of a /-butyl hydroperoxide (1 % by weight in water) and 0.07 g of a 1 % sodium sulfite solution. With the onset of the polymerization, the temperature rose to 50.1 °C within about 1 h 56 min.
  • Aqueous polyacrylamide concentrate comprising a copolymer comprising 69.4 wt.%
  • a 5 L beaker with magnetic stirrer, pH meter and thermometer was charged with 36.63 g of sodium acrylate (35% by weight in water), 1876.6 g of distilled water, 57.01 g of acrylamide (52% by weight in water), 6 g of diethylenetriaminepentaacetic acid pentasodium salt (Trilon ® C; 5% by weight in water), and 0.21 g of the stabilizer sodium 2-mercaptobenzothiazole (Na-MBT; 50% by weight in water).
  • Trilon ® C diethylenetriaminepentaacetic acid pentasodium salt
  • Na-MBT stabilizer sodium 2-mercaptobenzothiazole
  • the monomer solution was transferred to a double jacketed reactor and heated to 40 °C. While heating, the solution was purged with nitrogen for approximately 20 min. The polymerization was initiated at once with 20 g of a 10% aqueous solution of the water-soluble azo initiator 2,2-Azobis (2-(2-imidazolin-2-yl) propan) dihydrochlorid (Wako VA044).
  • Aqueous polyacrylamide concentrate comprising a copolymer comprising 69.4 wt.%
  • a 5 L beaker with magnetic stirrer, pH meter and thermometer was charged with 87.21 g of sodium acrylate (35% by weight in water), 1750 g of distilled water, 135.74 g of acrylamide (52% by weight in water), 6 g of diethylenetriaminepentaacetic acid pentasodium salt (T rilon ® C; 5% by weight in water), and 0.5 g of the stabilizer sodium 2-mercaptobenzothiazole (Na-MBT; 50% by weight in water).
  • Na-MBT stabilizer sodium 2-mercaptobenzothiazole
  • the monomer solution was transferred to a double jacketed reactor and heated to 40 °C. While heating, the solution was purged with nitrogen for approximately 20 min. The polymerization was initiated at once with 20 g of a 10% aqueous solution of 2,2-azobis (2-(2-imidazolin-2-yl) propan) dihydrochlorid (Wako VA044). With the onset of the polymerization, the temperature rose to 49 °C within about 10 min.
  • the maximum temperature of 49 °C was maintained for 2 h, then the solution was heated up to 60 °C and maintained for further 3 h. The aqueous polyacrylamide solution was kept for further testing.
  • Aqueous polyacrylamide concentrate comprising a copolymer comprising 69.4 wt.% (75.0 mol%) of acrylamide and 30.6 wt.% (25 mol%) of sodium acrylate; stabilized with
  • Solid content of 5 % by weight - Solution polymerization A 5 L beaker with magnetic stirrer, pH meter and thermometer was charged with 87.21 g of sodium acrylate (35% by weight in water), 1745 g of distilled water, 135.74 g of acrylamide (52% by weight in water), 6 g of diethylenetriaminepentaacetic acid pentasodium salt (T rilon C; 5% by weight in water), and 0.5 g of the stabilizer sodium 2-mercaptobenzothiazole (Na-MBT; 50% by weight in water).
  • Na-MBT stabilizer sodium 2-mercaptobenzothiazole
  • the monomer solution was transferred to a double jacketed reactor and heated to 40 °C. While heating, the solution was purged with nitrogen for approximately 20 min. The polymerization was initiated by dropwise (0.2 g / min; flow rate of 0.25) addition of 20 g of a 10% aqueous solution of 2,2-azobis (2-(2-imidazolin- 2-yl) propan) dihydrochlorid (Wako VA044) over 100 min using a squeezing pump. Then, the solution was heated up to 60 °C and maintained for further 3 h.
  • the aqueous polyacrylamide was kept for further testing.
  • Example 5 Aqueous polyacrylamide concentrate comprising a copolymer comprising 69.4 wt.% (75.0 mol%) of acrylamide and 30.6 wt.% (25 mol%) of sodium acrylate; stabilized with 0.25 wt.% Na-MBT (relating to polymer).
  • a 5 L beaker with magnetic stirrer, pH meter and thermometer was initially charged with 122.09 g of sodium acrylate (35% by weight in water), 1660.1 g of distilled water, 190.3 g of acrylamide (52% by weight in water), 6 g of diethylenetriaminepentaacetic acid pentasodium salt (T rilon ® C; 5% by weight in water), and 0.7 g of the stabilizer sodium 2-mercaptobenzothiazole (Na-MBT; 50% by weight in water).
  • the monomer solution was transferred to a double jacketed reactor and heated to 40 °C. While heating, the solution was purged with nitrogen for approximately 20 min. The polymerization was initiated at once with 20 g of a 10% aqueous solution of 2,2-azobis (2-(2-imidazolin-2-yl) propan) dihydrochlorid (Wako VA044). With the onset of the polymerization, the temperature rose to 52 °C within about 10 min. The maximum temperature of 52 °C was maintained for 2 h, then the solution was heated up to 60 °C and maintained for further 3 h.
  • the aqueous polyacrylamide solution was kept for further testing.
  • Aqueous polyacrylamide concentrate comprising a copolymer comprising 60.0 wt.% (72.3 mol%) of acrylamide, 30.0 wt.% (27.3 mol%) of sodium acrylate and 10.0 wt.% (0.34 mol%) of an associative monomer Solid content of 5 % by weight - Solution polymerization
  • H2C CH-0-(CH2)4-0-(E0)24.5-(Bu0)i6-(E0)3.5
  • the monomer solution was transferred to a double jacketed reactor and heated to 50 °C. While heating, the solution was purged with nitrogen for approximately 20 min.
  • the polymerization was initiated at once with 10 g of a 10% aqueous solution of 2,2-azobis (2-(2-imidazolin-2-yl) propan) dihydrochlorid (Wako VA044). With the onset of the polymerization, the temperature rose to 52 °C within about 10 min. The maximum temperature of 52 °C was maintained for 4 h.
  • the aqueous polyacrylamide solution was kept for further testing.

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Abstract

La présente invention concerne un procédé de fourniture de concentrés de polyacrylamide aqueux, le procédé comprenant la préparation des concentrés à un emplacement A par polymérisation radicalaire d'une solution de monomère aqueux comprenant au moins de l'eau et de 1 % à 14,9 % en poids - relativement au total de tous les composants de la solution de monomère aqueux - de monomères solubles dans l'eau, éthyléniques insaturés, lesdits monomères solubles dans l'eau, éthyléniques insaturés, comprenant au moins de l'acrylamide, et transportant les concentrés aqueux obtenus de polyacrylamide vers un emplacement différent B par un moyen de transport sélectionné dans le groupe des camions, wagons ou bateaux.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021191041A1 (fr) 2020-03-26 2021-09-30 Basf Se Procédé et installation pour fabriquer des gels de polyacrylamide aqueux

Citations (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2059241A1 (de) 1970-12-02 1972-06-22 Cassella Farbwerke Mainkur Ag Verfahren zur Herstellung wasserloeslicher Polymerisate
US4248304A (en) 1979-11-16 1981-02-03 Nalco Chemical Company Large scale production of inexpensive flooding polymers for tertiary oil recovery
ZA833812B (en) 1982-05-26 1984-02-29 Anikem Pty Ltd A process for preparing acrylamide polymers
WO1984000967A1 (fr) 1982-08-27 1984-03-15 Marathon Oil Co Appareil et procede de production continue de solutions polymeres aqueuses
US4605689A (en) 1984-11-28 1986-08-12 American Cyanamid Company Preparation of aqueous polyacrylamide solutions for enhanced oil recovery
US4845192A (en) 1984-03-29 1989-07-04 Diatec Polymers Method of rapidly dissolving polymer gels in water
WO1997021827A1 (fr) 1995-12-12 1997-06-19 Allied Colloids Limited Production d'acrylate d'ammonium
WO2003066190A1 (fr) 2002-02-08 2003-08-14 Ciba Specialty Chemicals Water Treatments Limited Procede et dispositif de degazage de liquides
US20040175809A1 (en) 2001-04-26 2004-09-09 Olaf Peterson Method for producing an aqueous acrylamide solution with a biocatalyst
WO2005054456A1 (fr) 2003-12-02 2005-06-16 Ciba Specialty Chemicals Water Treatments Limited Souche de rhodococcus rhodochrous ncimb 41164 et son utilisation comme producteur de nitrile hydratase
WO2005054489A1 (fr) 2003-12-02 2005-06-16 Ciba Specialty Chemicals Water Treatments Limited Fabrication d'amides
WO2010133527A2 (fr) 2009-05-20 2010-11-25 Basf Se Copolymères associatifs à groupes hydrophobes
EP2336346A1 (fr) 2008-10-03 2011-06-22 Dia-Nitrix Co., Ltd. Procédé de production d'acrylamide
WO2012069478A1 (fr) 2010-11-24 2012-05-31 Basf Se Procédé d'extraction de pétrole en utilisant des copolymères associatifs hydrophobes
CN202492486U (zh) 2012-04-10 2012-10-17 天津凯英科技发展有限公司 阳离子聚丙烯酰胺胶体生产用通氮除氧净化装置
EP2518154A1 (fr) 2009-12-25 2012-10-31 Dia-Nitrix Co., Ltd. Procédé pour produire de l'acrylamide en utilisant un catalyseur microbien
JP2014176344A (ja) 2013-03-14 2014-09-25 Mitsui Chemicals Inc 反応経過を監視することを特徴とするアミド化合物の製造方法およびアミド化合物の製造装置
WO2015024865A1 (fr) 2013-08-22 2015-02-26 Basf Se Compositions stabilisées contenant des polymères acrylamide et procédé d'extraction de pétrole tertiaire à l'aide de ces compositions
JP2015057968A (ja) 2013-09-18 2015-03-30 三井化学株式会社 アミド化合物の製造方法およびアミド化合物の製造装置
WO2015086468A1 (fr) 2013-12-13 2015-06-18 Basf Se Procédé d'extraction de pétrole
WO2015158517A1 (fr) 2014-04-15 2015-10-22 Basf Se Procédé de production d'homo- ou de copolymères hydrosolubles comprenant du (méth)acrylamide
WO2016006556A1 (fr) 2014-07-10 2016-01-14 三菱レイヨン株式会社 Procédé pour la production de composé et système de production de composé utilisé dans ledit procédé de production
WO2016050818A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé pour préparer une solution d'acrylamide aqueuse à faible concentration en acide acrylique
WO2016050861A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé de culture de micro-organisme présentant une activité de nitrile hydratase
WO2016050816A2 (fr) 2014-09-30 2016-04-07 Basf Se Moyens et procédés de production de composés amide avec moins d'acide acrylique
WO2016050819A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé de préparation d'une solution d'acrylamide ayant une faible concentration d'acide acrylique
WO2016050817A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé de production d'acrylamide à partir d'acrylonitrile dans une solution aqueuse
WO2016131940A1 (fr) 2015-02-20 2016-08-25 Basf Se Procédé de production de compositions de polyacrylamide stabilisées
WO2016131941A1 (fr) 2015-02-20 2016-08-25 Basf Se Procédé de production de polyacrylamides stabilisée
WO2017055518A1 (fr) 2015-09-30 2017-04-06 Basf Se Moyen et procédé de production d'un composé amide
WO2017167803A1 (fr) 2016-03-29 2017-10-05 Basf Se Procédé de production d'une solution de polyacrylamide à viscosité accrue
WO2017186567A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé et appareil de production d'une solution aqueuse de polymère
WO2017186697A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé de préparation d'une solution aqueuse de polyacrylamide
WO2017186698A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé de préparation d'une solution aqueuse de polyacrylamide
WO2017186685A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé de préparation d'une solution aqueuse de polyacrylamide
WO2019081319A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081323A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081320A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081318A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081327A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081321A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081330A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide

Patent Citations (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2059241A1 (de) 1970-12-02 1972-06-22 Cassella Farbwerke Mainkur Ag Verfahren zur Herstellung wasserloeslicher Polymerisate
US4248304A (en) 1979-11-16 1981-02-03 Nalco Chemical Company Large scale production of inexpensive flooding polymers for tertiary oil recovery
ZA833812B (en) 1982-05-26 1984-02-29 Anikem Pty Ltd A process for preparing acrylamide polymers
WO1984000967A1 (fr) 1982-08-27 1984-03-15 Marathon Oil Co Appareil et procede de production continue de solutions polymeres aqueuses
US4845192A (en) 1984-03-29 1989-07-04 Diatec Polymers Method of rapidly dissolving polymer gels in water
US4605689A (en) 1984-11-28 1986-08-12 American Cyanamid Company Preparation of aqueous polyacrylamide solutions for enhanced oil recovery
WO1997021827A1 (fr) 1995-12-12 1997-06-19 Allied Colloids Limited Production d'acrylate d'ammonium
US20040175809A1 (en) 2001-04-26 2004-09-09 Olaf Peterson Method for producing an aqueous acrylamide solution with a biocatalyst
WO2003066190A1 (fr) 2002-02-08 2003-08-14 Ciba Specialty Chemicals Water Treatments Limited Procede et dispositif de degazage de liquides
WO2005054489A1 (fr) 2003-12-02 2005-06-16 Ciba Specialty Chemicals Water Treatments Limited Fabrication d'amides
WO2005054456A1 (fr) 2003-12-02 2005-06-16 Ciba Specialty Chemicals Water Treatments Limited Souche de rhodococcus rhodochrous ncimb 41164 et son utilisation comme producteur de nitrile hydratase
EP2336346A1 (fr) 2008-10-03 2011-06-22 Dia-Nitrix Co., Ltd. Procédé de production d'acrylamide
WO2010133527A2 (fr) 2009-05-20 2010-11-25 Basf Se Copolymères associatifs à groupes hydrophobes
EP2518154A1 (fr) 2009-12-25 2012-10-31 Dia-Nitrix Co., Ltd. Procédé pour produire de l'acrylamide en utilisant un catalyseur microbien
WO2012069478A1 (fr) 2010-11-24 2012-05-31 Basf Se Procédé d'extraction de pétrole en utilisant des copolymères associatifs hydrophobes
CN202492486U (zh) 2012-04-10 2012-10-17 天津凯英科技发展有限公司 阳离子聚丙烯酰胺胶体生产用通氮除氧净化装置
JP2014176344A (ja) 2013-03-14 2014-09-25 Mitsui Chemicals Inc 反応経過を監視することを特徴とするアミド化合物の製造方法およびアミド化合物の製造装置
WO2015024865A1 (fr) 2013-08-22 2015-02-26 Basf Se Compositions stabilisées contenant des polymères acrylamide et procédé d'extraction de pétrole tertiaire à l'aide de ces compositions
JP2015057968A (ja) 2013-09-18 2015-03-30 三井化学株式会社 アミド化合物の製造方法およびアミド化合物の製造装置
WO2015086468A1 (fr) 2013-12-13 2015-06-18 Basf Se Procédé d'extraction de pétrole
WO2015158517A1 (fr) 2014-04-15 2015-10-22 Basf Se Procédé de production d'homo- ou de copolymères hydrosolubles comprenant du (méth)acrylamide
WO2016006556A1 (fr) 2014-07-10 2016-01-14 三菱レイヨン株式会社 Procédé pour la production de composé et système de production de composé utilisé dans ledit procédé de production
WO2016050818A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé pour préparer une solution d'acrylamide aqueuse à faible concentration en acide acrylique
WO2016050861A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé de culture de micro-organisme présentant une activité de nitrile hydratase
WO2016050816A2 (fr) 2014-09-30 2016-04-07 Basf Se Moyens et procédés de production de composés amide avec moins d'acide acrylique
WO2016050819A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé de préparation d'une solution d'acrylamide ayant une faible concentration d'acide acrylique
WO2016050817A1 (fr) 2014-09-30 2016-04-07 Basf Se Procédé de production d'acrylamide à partir d'acrylonitrile dans une solution aqueuse
WO2016131940A1 (fr) 2015-02-20 2016-08-25 Basf Se Procédé de production de compositions de polyacrylamide stabilisées
WO2016131941A1 (fr) 2015-02-20 2016-08-25 Basf Se Procédé de production de polyacrylamides stabilisée
WO2017055518A1 (fr) 2015-09-30 2017-04-06 Basf Se Moyen et procédé de production d'un composé amide
WO2017167803A1 (fr) 2016-03-29 2017-10-05 Basf Se Procédé de production d'une solution de polyacrylamide à viscosité accrue
WO2017186567A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé et appareil de production d'une solution aqueuse de polymère
WO2017186697A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé de préparation d'une solution aqueuse de polyacrylamide
WO2017186698A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé de préparation d'une solution aqueuse de polyacrylamide
WO2017186685A1 (fr) 2016-04-26 2017-11-02 Basf Se Procédé de préparation d'une solution aqueuse de polyacrylamide
WO2019081319A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081323A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081320A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081318A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081327A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081321A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide
WO2019081330A1 (fr) 2017-10-25 2019-05-02 Basf Se Procédé de production de solutions aqueuses de polyacrylamide

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Week 198418, 10 April 2011 Derwent World Patents Index; AN 1984-113907, XP002791201 *
L. Z. ROGOVINA ET AL., POLYMER SCIENCE, vol. 50, no. 1, 2008, pages 85 - 92

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021191041A1 (fr) 2020-03-26 2021-09-30 Basf Se Procédé et installation pour fabriquer des gels de polyacrylamide aqueux

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