LT4330B - Oil and gas field chemicals - Google Patents

Abstract

Invention describes method of increasing effectiveness of extraction chemicals, reducing amount of insertion and closure-sustenance operations, necessary to increase scale of extraction from oil-well. The method consists of insertion of an easily water mixable mixture, containing two components: (a) easily water mixable active surface substance, the alkyltriglycolether, and (b) at least one easily water mixing oil or gas extraction chemical, i.e. thin coating inhibitor; the afore mentioned mixture components are being inserted into rock structure through an industrial borehole or as a composition prepared in advance, or at the same time equivalently or one after another at any order.

Description

The present invention describes petrochemical chemicals, particularly suitable for oil field exploitation, and their use.

It is well known to use some chemicals to enhance oil extraction and production from these wells. One such method is described in US-A3481870, which discloses methods and compositions for removing organic sediments such as paraffin, waxes and asphalt and bituminous materials on industrial surfaces: on a mesh filter or inner tube, on a pump, on a carcass. or in borehole pipelines. Compositions used include glycol ethers such as isobutyl triglycol cholesterol, oxyethylated butylphenol, isopropanol, and water. However, it has not been revealed that borehole operations suffer from inorganic sediment problems, such as plaque, and that the method described may inhibit the formation of plaque.

Plaque inhibitors are known among oil field chemicals and are used in well operations to inhibit plaque formation in rocks and / or production facilities, wells and on their surface. Not only does the formation of deposits by surface treatment limit the size of the rock pores (known as the formation loss), which, in turn, results in a slower rate of oil and / or gas production, but also blocks pipelines and installations. To prevent this phenomenon, the production borehole is specially treated to remove clogs; for this purpose, the aqueous composition containing the plaque inhibitor is injected into the production well, usually by pressure injection into the rock, and maintained there. The injected composition adsorbs on the rock surface, thereby inhibiting plaque formation, leaching slowly into the water formed, thereby maintaining access to oil in the rock; this closure-retention treatment must be regular, for example at least once or several times a year, maintaining a high rate of production, and is considered downtime because production is not occurring at that time. Over the course of a year, total production is reduced by downtime caused by shut-down and maintenance operations, just as, incidentally, production declines when plaque formation occurs.

Means and methods have been invented to increase the efficiency of extraction chemicals, especially with regard to plaque inhibitors, by reducing the amount of embossing / closing-retaining operations required and thereby increasing the extraction rate. In addition, a mixture that is resistant to storage and transport has been developed.

Accordingly, the present invention is a technological process for increasing the efficiency of extractive chemicals by reducing the amount of embossing and closure-retention operations required to increase extraction rates from the oil well, inhibiting plaque formation; the process involves injecting into an oil rock a readily water-miscible mixture containing:

(a) a water-miscible surfactant which is an alkyltriglycol cholesterol; and (b) at least one water-miscible oil or gas field chemical, containing a plaque inhibitor, under pressure and maintaining the mixture in the rock for a sufficient period of time to adsorb to said rock components; manifest as a plaque inhibitor; the components of said mixture are injected into the rock either preformed in a single homogeneous composition or simultaneously in parallel or gradually in any order.

The alkyl group of the alkyltriglycol ether may be a straight or branched chain and accordingly has 3-6 carbon atoms, preferably 3-5 carbon atoms. Preferably, the alkyl group of the alkyltriglycol ether has 4 carbon atoms and is n-butyltriglycol ether (also known as triethylene glycol mono-n-butyl ether).

When the mixture is injected into the rock as a single preformulated composition, the mixture is a homogeneous aqueous solution in which the two components are in a special relationship to each other to maintain homogeneity of the solution.

Thus, an essential object of the present invention is a homogeneous mixture comprising an aqueous medium, a) at least one surfactant containing 1-20% w / w n-butyltriglycol ether, b) 1-25% w / w% of at least one oil or gas field extraction chemical. .

In another aspect, the present invention is a method of introducing a homogeneous mixture containing an oil or gas field extraction chemical, consisting of a plaque inhibitor and a surfactant, into an oil or gas rock, which involves sliding the homogeneous mixture down into a production well.

The invention also contemplates the use of a homogeneous mixture comprising an oil / gas field chemical containing plaque inhibitors to enhance production efficiency, in particular by prolonging the chemical retention of rock.

The expression is a homogeneous mixture, which means that the formulation is a single phase system. That is, each component is itself homogeneous and readily miscible with water when added to the rock gradually or simultaneously, and is also homogeneous when incorporated into the rock in the form of a pre-formed composition.

It should be understood that where the components of a mixture are added simultaneously but separately or gradually, it is not incorporated in the form of a pre-formulated separate composition and therefore the concept of a homogeneous mixture is not applicable. However, in this particular case, it is desirable that each component used is homogeneous and also miscible with water. A suitable pH of the mixture is in the range of 0.1 to 6.0 and is generally only relevant when using a pre-formulated composition. It is desirable to control the pH of component (b) as indicated.

Thus, the surfactant used in the invention contains at least one alkyltriglycol ether and at least one extraction chemical, and remains pure and stable at ambient temperature and at temperatures up to at least 45 ° C. The surfactant is present in the mixture in an amount of 120% by weight, preferably 5-15% by weight, most preferably 5-12% by weight. The present invention may use streams of a by-product of the glycol ether production process which contain a high proportion of alkyl triglycol ethers such as n-butyl triglycol ether. One such by-product stream contains approximately 75% w / w n-butyltriglycol ether,

2.5% w / w butyldiglycol ether, 19% w / w butyl tetraglycol ether and 2% w / w butyl pentaglycol ether. The relative proportions of the components (a) and (b) of the mixture can vary over a wide range, depending on whether the components are added to the rock simultaneously, gradually or as a separate pre-formulated composition, but it is important to maintain homogeneity of the mixture at operating temperatures and salinity. .

In some cases, at relatively higher surfactant concentrations or at relatively higher or extremely low temperatures, it is possible that, under these conditions, the reduced solubility of one or more components of the mixture may result in loss of homogeneity. In these cases, small amounts of solubility enhancing agents such as lower aliphatic alcohol, especially methanol or ethanol, may be added to the inhomogeneous, pre-formulated mixture, or partial substitution of the surfactant may be employed.

Preformulated homogeneous mixtures of the present invention in addition to alkyltriglycol ether may also have a total river, marine, industrial total 0-250 g / l, e.g., a bitter mixture solvent such as a lower aliphatic alcohol, especially methanol or ethanol.

The aqueous medium of the mixture may be fresh, tap or rock water having a salinity of 5-50 g / l, and may have a pH of 0.5-9. When used in seawater, the mixture usually has a strongly acidic pH of 0.1-1.5 due to the presence of strongly acidic chemicals - plaque inhibitors. In these cases, it may be necessary to neutralize the acidity by using alkali metal hydroxide, especially sodium, potassium or lithium hydroxide in the appropriate range of 0.1-6.0. It has been found that the use of lithium hydroxide, where necessary to maintain homogeneity of the mixture, in place of other alkali metals in the role of hydroxide neutralizing agent, provides tolerance to higher levels of surfactant in the mixture.

Oil and gas extraction chemicals are inhibitors. The plaque inhibitor is effective in inhibiting the formation of calcium and / or barium deposits; it is better to use it in threshold quantities than stoichiometric. It may be a water-soluble organic molecule having at least 2 carboxylic and / or phosphonic acid and / or sulfuric acid groups, e.g., 2 to 30 such groups. Very well, the plaque inhibitor is an oligomer or a polymer or may be a monomer with at least one hydroxyl group and / or an amino nitrogen atom, particularly in a hydroxycarboxylic acid or a hydroxy or aminophosphonium or sulfuric acid. The inhibitor is mainly used to inhibit calcium and / or barium plaque. Examples of such inhibitors include aliphatic phosphonic acids having from 2 to 50 carbon atoms, such as hydroxyethyldiphosphonic acid, and aminoalkyl phosphonic acids, such as polyaminomethylene phosphonates having from 2 to 10 N atoms, e.g., each bearing at least one methylenephosphonic acid group. ; examples of the latter are ethylenediamine tetra (methylene phosphonate), diethylenetriaminepenta (methylene phosphonate) and triamine and tetraminopolymethylene phosphonates with 2-4 methylene groups between each M atom, each phosphonate having at least 2 of the methylene groups being different (e.g. as described in EP-A- 479462). polycarboxylic acids as polymeric anions

Other plaque inhibitors include lactic or tartaric acids, and compounds such as polyvinylsulfonic acid and poly (meth) acrylic acids, which may have at least several phosphonyl or phosphinyl groups as in phosphinyl polyacrylates. Plaque inhibitors are suitable, at least in part, in the form of their alkali metal salts, e.g., sodium.

The amount of mining chemicals - plaque inhibitors used is 1-25% w / w, based on the total composition, suitable amount is 5-15% w / w, preferably 6-10% w / w. In order to achieve a homogeneous mixture, the amount used within these ranges depends on the nature of the chemical used and its intended use.

relatively molecule, surface

It is important that the compositions of the present invention, especially those having a preformulated homogeneous composition, remain clear and stable over a temperature range of at least 45 ° C. However, it is possible to formulate mixtures within the above-mentioned component concentrations that remain stable over a much wider temperature range, e.g., from ambient temperature to well operating temperature (e.g., 90 to 150 ° C, especially about 110 ° C) when injected. In the present invention, when the components of a mixture are pressurized into the service bore, either individually or as a pre-formulated composition, the chemicals in the mixture are adsorbed to the rocks and remain there for a long time. The use of a relatively small, e.g. C3-C6 (alkyl) triglycol ether, as an active agent avoids the use of large surfactant molecules (having > C6 alkyl groups), thereby reducing any risk of formation of surfactant assemblies, which in turn may cause large viscosity of emulsions blocking wells.

Such a mixture may also contain other components, such as (i) other extraction chemicals or (ii) co-solvents, which, when necessary, provide stability of the mixture at relatively high temperatures, or when the surfactant is used at quarterly higher concentrations, than the specified interval. However, mixtures should be substantially free of water immiscible components. Other examples of extractive chemicals include compounds that may be inhibitors of (i) corrosion, (ii) gas hydrate formation, (iii) wax, or (iv) asphaltene precipitation; or may be a hydrogen sulfide acceptor or a wax dispersant. Here:

(i) Corrosion inhibitors are compounds intended to inhibit corrosion of steel, particularly under anaerobic conditions, and are particularly capable of forming a thin layer that can coat a metal surface, such as a steel surface such as an oil pipeline wall. Such compounds may be long-chain aliphatic hydrocarbyl N-heterocyclic compounds wherein the aliphatic hydrocarbyl group may be as previously defined for the hydrophobic group; mono- or diethylenically unsaturated aliphatic groups, for example having from 8 to 24 carbon atoms, such as oleyl, are suitable. The N-heterocyclic group may have 1-3 ring nitrogen atoms with 5-7 ring atoms; imidazole and imidazoline rings are suitable. The ring may also contain an aminoalkyl such as 2-aminoethyl or a hydroxyalkyl such as 2-hydroxyethyl. Imidazoline can be used.

(ii) The gas hydrate inhibitor may be a solid polar compound which may be a polyoxyalkylene compound or an alkanolamide, or a tyrosine or a phenylamine.

(iii) the asphaltene inhibitor may be an amphoteric fatty acid or an alkyl succinate salt; the wax inhibitor may be a polymer such as an olefin polymer such as polyethylene or a copolymer ester such as an ethylene-vinyl acetate copolymer and the wax dispersant may be a polyamide. The hydrogen sulfide acceptor may be an oxidant such as an inorganic peroxide such as sodium peroxide or chlorine dioxide, or an aldehyde such as 1-10 carbon atoms such as formaldehyde or glutaraldehyde, or (meth) acrolein.

When used as preformed homogeneous mixtures of the present invention, they can be prepared by adding the surfactant (a) to an aqueous solution of an oil or gas field chemical (plaque inhibitor) (b) under gentle agitation. If the prepared material is initially cloudy, then the relative proportions of the ingredients are slightly adjusted, either by changing the type, amount or temperature of the total solvent. Its viscosity is good if it is easily pumped down into the borehole at a tank temperature of, for example, 100 ° C. A pre-formulated mixture of the present invention may be prepared from a concentrate of (a) ii * (b) ingredients, which may be delivered to the place of use; here it is mixed in appropriate proportions with the aqueous medium to obtain the required homogeneity and complete dissolution of the chemical. The pre-prepared mixture may be pressurized into the oily rock zone through a production well, e.g., downstream of the core, followed by a separate fluid to accelerate the pre-prepared mixture into the oily zone; there may be excess liquid and it may be sea water or diesel oil. The mixture is then left (sealed) in the oil zone while oil production is temporarily halted. During this process, the injected mixture is forced through the oily zone under pressure. During the braking period, the injected mixture contacts the reservoir fluids, forming an in-phase or three-phase system, which can be in the form of an emulsion and exposes the required surface and the appropriate phase. This is the so-called caveat effect, which supports the extraction of oil from such areas. The mixtures of the present invention often achieve the required 5-50 hours. contact time, eg 20-30 hours. After this period, oil production may resume. In the case where the extraction chemical is a plaque inhibitor, initially the rate of oil extraction until the soluble calcium content of the production water is high. Over time, for example, 2-4 months, the rate of extraction will slow down and the amount of salt that can be dissolved will also decrease, indicating the possible formation of plaque in the rocks; then extraction can be stopped and a new amount of mixture injected into the well. Similar methods can be used for asphaltene inhibition, wax inhibition or dispersion, and hydrogen sulphide acceptance, while the mixture is generally continuous for inhibition of corrosion and gas hydrates.

A further feature of the compositions of the present invention is that when a multiphase composition containing, for example, a plaque inhibitor, petroleum and alkyltriglycol ether is recovered on the surface after the above impregnation procedure and subsequent cooling, most glycol ether enters the aqueous phase faster than the oil of the composition. phase. In this way, the glycol ether does not cause any problems in subsequent extraction or purification operations, such as turbidity in the fuel due to dissolved water in the glycol ether. In addition, if the separated aqueous phase is discarded, the biodegradation of the dissolved glycol ether in the thermal seabed may be relatively rapid, thereby reducing contamination. In addition, the compositions of the present invention can increase the efficiency of oil and gas field chemicals, for example, in the case of plaque inhibitors, by requiring twice as many chemicals per year, and by correspondingly reducing downtime due to application and closure of chemicals. The process can be controlled with equal efficiency by gradually introducing the components of the mixture into the production well.

The invention is illustrated by the following examples.

example

1.1 The mixture used in the following experiments, which was able to remain clean and transparent at ambient temperature up to 95 ° C, had the following composition:

Deąuest® 2060S (inhibitor, ex Monsanto) 10 parts by weight Seawater 75 parts by weight Surfactant 15 parts by weight The pH of this mixture was not controlled.

1.2 The stability test was carried out using a commercially available mixture of 15 parts by weight of surfactant glycol ethers (according to the invention) having the following composition in the above general mixture (1.1):

n-Butyltriglycol cholesterol n - Butyldiglycol ether n-Butyl tetraglycol cholesterol n-Butyl pentaglycol cholesterol w / w%

2.5 m / m% 19.0 m / m% 2.0 m / m%

This mixture is a homogeneous yellow liquid. During mixing and heating of this mixture, a phase transition with an onset of turbidity was observed starting at room temperature (when it was single phase) at 95.5 ° C. Without stirring and stored at a higher temperature, a colorless individual phase is formed above the broader lower yellow phase (apparently the upper phase consists predominantly of n-butyl triglycerol ether).

example

The purpose of this example was to determine whether the above blends, when blended with Forties Main-Oil Line Fluids (FMOLF) crude oil, form a middle phase in a three-phase blend (according to Nelson, RC and Pope, GA authentic publication, Phase Relationships in Chemical Flooding, U.S. Petroleum. Engineering Society, Publication No. SPE 6773, issued by the American Institute of Mining Metallurgical and Petroleum Engineers, Ine. (1977) at 95 ° C, thus demonstrating the ability of the mixtures under study to absorb (absorb) oil (which may otherwise be incorporated into rocks). ).

After heating under stirring, the homogeneous yellow solution described above (10 g, contains a surfactant at temperature with the addition of FMOLF (2g)).

mixture (1.2) (1.5 g commercial mixture), monitored at 95 ° C for a three-phase

These three phases are: the upper black liquid (visibly predominantly crude oil), the middle orange-red phase (apparently a predominantly commercial surfactant mixture), and the lower yellow phase (probably a predominantly aqueous solution of Deuuest®). This three-phase system lasted more than 7 days and apparently could last indefinitely. In addition, during mixing, the middle phase dissipated, easily forming droplets or filaments that descended down to the lower phase. While standing, the middle and lower phases wetted the glass wall of the test vessel to a similar degree. These observations coincided with the low fission surface tension between the aqueous and petroleum phases as described in Nelson and Pope, supra.

example

All subsequent experiments used a homogeneous mixture having the same overall composition as in Example 1. However, in this case, first, 10 parts of Deąuest® 2060S were mixed with 75 parts of seawater and then adjusted to pH 2 using solid sodium hydroxide (Examples 3.1-3.3) or solid lithium hydroxide monohydrate (Examples 4.1-4.3). As in Example 1 above, 15 parts by weight of surfactant were used anyway.

This mixture remained homogeneous (i.e., clean and translucent) under ambient temperature to 110 ° C under pH control. The purpose of these examples was to determine whether the triple blend consisting of the above blend, when mixed with North Alwyn crude oil from the North Sea in the United Kingdom (Reference Weight, API no. From

37.2 to 42.1), as published by the Geological Society, London, United Kingdom Oil and Gas Field 25 Years Commemorative Volume, Memoir No.14, published by ILAbbotts (1991), forms an intermediate phase at 110 ° C as described. in Example 2 above.

3.1. The experiment is conducted with a homogeneous mixture containing 15 parts by weight of a commercial surfactant mixture used in Example 1.2. During the heating and stirring of this mixture, a transition phase between 48-49 ° C was observed between room temperature (when one phase was present) and when turbidity occurred.

3.2 The following experiment was conducted using the same mixture as in Example 3.1 except that the 7 parts by weight of the commercial surfactant mixture used in the mixture was replaced by 7 parts by weight of methanol.

During the heating of this sample containing methanol, no transition phase was observed in a Buchi glass pressure tube from room temperature (once phase) to 90 ° C.

This experiment shows that using mixtures with a relatively high surfactant concentration, the homogeneous composition of the mixture can be corrected with methanol, thereby restoring homogeneity and significantly increasing the stability of the mixture.

3.3 By heating and stirring the mixture as in Example 3.2 (25 g, containing 2.0 g of a commercial surfactant mixture as in Example 1.2 and 1.75 g of methanol) in the presence of North Alwyn crude oil (2 g) in a Buchi glass. a three-phase system is observed in the pressure tube at 110 ° C. These phases and their behavior are similar to those of Example 2.

example

4.1 A mixture of 15 parts by weight of a commercial surfactant mixture as in Example 1.2 but differently having the total composition defined in Example 3 was gradually heated and stirred in a Buchi glass pressure tube, starting from room temperature where the mixture had only one phase. The transition phase was observed between 67-68 ° C, when turbidity appeared.

4.2 Experiment 4.1 was repeated with the exception that in this example 6 parts by weight of a commercial surfactant mixture were replaced by 6 parts by weight of methanol.

Gradually heat and stir this adjusted methanol-containing mixture in a Buchi glass pressure tube, starting from room temperature (when the mixture was single-phase) to 109 ° C and then maintained for 1 hour. at elevated temperature of 115 ° C, the transition phase was not observed.

This experiment again demonstrates that using mixtures with relatively high surfactant concentrations, replacing part of the surfactant with methanol, can restore the homogeneity of the surfactant and significantly increase the stability of the mixture.

4.3 Heating and stirring the mixture according to Example 3.2 (30.0 g, contains 2.7 g of the surfactant used in Example 1.2 and 1.8 g of methanol) together with added North Alwyn crude oil (4 g) in a Buchi glass pressure tube, 110 ° At C, a three-phase system is observed. These phases and behaviors are similar to the results of Example 2 above.

example

The homogeneous mixture of Example 3.2 above was compared with the control (not according to the invention) containing only Deąuest® 2060S (10 parts by weight) in terms of inhibition of plaque formation by simulating the impregnation process.

In the North Sea, 15 cm long vertical cores were drilled from the middle of the Brent Group sandstone. Each 15 cm core was successfully degreased using solvent extraction with toluene followed by methanol / chloroform after pre-mounting on a vertical column with inlet and outlet taps. Degassed seawater at pH 5.5 was allowed to pass through the core at room temperature until saturation. Thereafter 150 m / h into the core. 5 volumes of degassed crude Brent oil (filtered to remove particles larger than 10 μg) were allowed to flow until no more water was collected through the outlet tap. The core was then heated to 110 ° C for 24 hours.

simulating tank temperature, 150 ml / h. injection of degassed seawater at pH 5.5 until no more oil was concentrated. The core then had saturation of the oil residue and saturation of the brine residue and thus mimicked the oily rock in the well.

The core was cooled to 40 ° C without gas entry and then 30 ml / h. 8-10 pairs of inhibitor medium (as described below) was infused at saturation rate. The cranes were then closed, the core heated again to 110 ° C and maintained at this temperature for 17 hours. Then 30 ml / hr through the core. seawater at pH 5.5 is run and samples of runoff are periodically collected and the level of inhibitor is analyzed until the concentration of inhibitor is less than 5 parts per million. The core is then cooled and filled with methanol before being dried and examined under a scanning electron microscope to control any effect on the clay or pore morphology; nothing like this was noticed.

Two series of experiments were performed using the above procedure, one with the mixture described in Example 3.2 and the other with a control containing the same concentration of w / w% suitable inhibitor and pH 2 and seawater only.

The relationship between the level of the sewage inhibitor and the volume of seawater passed through the core (expressed as the pore volume of the solution) is a measure of the amount of inhibitor initially adsorbed on the rock and its rate of excretion, i. i.e., a measure of the rate at which the inhibitor is removed from the rock during manufacture (i.e., resistance to leaching) and thus is a measure of the effectiveness of plaque inhibition over time. The results are shown below:

table

Example 5 Control (comparative test) Pore volumes Inhibitor almost (mils) Pore volumes Inhibitor almost (mils) 0.08 33122 0.06 22040 0.45 11962 0.69 3982 0.95 4445.8 0.94 3054 1.95 4231.2 2.19 258.4 9.81 1054.4 9.56 84.8 102.51 148.17 107.69 45.6 189 80.1 188.94 31.5 255.5 67.5 292.38 18.7 393.67 35.3 401.75 12th 454.67 25.7 489.25 8.7 to 551.2 17.5 591.75 5.2 611.09 15th 629.63 4.9 [ 705.68 10.6 j ! 830.06 7th 920 4.1 !

example

This example is implemented using a sand block instead of the core used in Example 5. Two series of tests were performed: (i) exact replication of Example 5 using a homogeneous solution, and (ii) repeat of Example 5, but now using the following appendix, where the surfactant is first introduced into the sand block, followed by an attack with a plaque inhibitor.

Mixture of the above components: Inhibitor - Deąuest® 2060S Seawater (i) for series prepared from

-10 parts by weight

-75 parts by weight

Commercial surfactant

Residual oil

PH temperature

- a mixture of 8 parts by weight 5 e.g. used materials and 7 parts by weight of methanol

- Forties Field crude (dried and without additives)

- 2.0

110 ° C

The process is then repeated for the control (base) experiment, where the homogenous mixture used contains 90 parts by weight of seawater and 10 parts by weight of Deguest® 2060S in the absence of surfactant.

Test (ii) is performed using a Clashach sand block placed in a 1.524 m (5 ft) metal tube. The block is filled with petroleum residue (using Forties Field Main Line Fluid) and flooded with seawater using the same temperature (110 ° C) and flow rates as in Example 5. In these experiments, the parameters prior to filling are obtained as follows: first, 8% by weight of a solution of the surfactant described above dissolved in seawater (pH adjustment if necessary) is added and closed for 12 hours. At 110 ° C, a portion of a plaque inhibitor similar to that used to obtain the baseline data without the use of a surfactant is further added. Baseline data were repeated with a sand block but using a 10 wt% Deguest 2060S solution in seawater adjusted to pH 2.0 and without the use of a surfactant for more accurate comparisons with the sand block.

The results are shown in Table 2:

table

Control (Basic) Secondary backfilling here phase before (adding Lee) Homogeneous phase Volume of Forums Inhibitory reas machine. (mil.d.) Pore volume Inhibi to - reas machine. (mil.d.) Pore volume Inhibit reas machine. (mil.d.! 2.04 1680 1.98 2240 1.98 1520 2.91 1120 2.84 2268 2.84 904 4.09 388 3.97 938 3.97 489 4.96 168 4.82 484 4.82 278 5.84 92.6 5.96 196 5.96 108 7th 43 7.09 84 7.09 52 7.9 25th 7.94 54 7.94 30th 8.76 20th 8.79 32 8.79 20th 9.92 14.4 9.9 22nd 9.9 1.4 11.97 12.2 11.91 12.8 11.91 11.6 14.84 8.4 14.75 10.4 14.75 8.4 18.1 7.4 18.15 8.4 18.15 5.8 20.12 7.4 20.14 8th 20.14 6.4;

example

This example was performed on a Tarbet core material using the procedure described in Example 5 and a homogeneous mixture of surfactant and plaque inhibitor Deąuest® 2086S as shown below.

The concentration of inhibitor used was 4% by weight and the mixture was prepared in distilled water. Therefore, the full composition of the mixture used was:

Deąuest® 2086S 15.7% w / w solution in distilled water, pH = 2 -85 parts

distilled water

-7 Parts

Example 1.2 commercial surfactant - 8 parts

Baseline data were obtained using Dequest® 2086S in seawater (as reported, 15.7 w / w%, respectively, 5 w / w% active ingredient), pH adjusted to 5.45. The data in Table 3 are for a homogeneous solution when used as described in Example 5.

The results are shown in Table 3:

table

Control (Basic) Homogeneous mixture 1 Pore volumes Inhibitor machine (mil.d) Pore volumes Inhibitor machine (mil.d) 1.67 369.47 1.73 2256 4.18 65.12 3.97 3611 10.57 27.7 9.7 737 16.95 19.58 17.31 403 29.72 12.97 29.1 275 47.28 10.85 45.96 206 101.15 7.7 101.25 76 158.61 6.48 152 30th

Claims (24)

DEFINITION OF INVENTION A method for increasing the efficiency of mining blends by reducing the amount of embossing and closure-retention operations required to increase oilfield extraction rates by inhibiting plaque formation by adding a water-miscible mixture consisting of: (a) water-miscible surfactant, which is an alkyltrichlicholether, and (b) retaining at least one water-miscible oil or gas extraction chemical, a plaque inhibitor, and maintaining said mixture in the rock for a time sufficient to effect closure. enabling the adsorption of the components of the mixture in the oil rock to act as a plaque inhibitor; the components of the mixture may be introduced into the rock structure either in the form of a preformed homogeneous composition, or in parallel or sequentially in any order. 2. A process according to claim 1, wherein the surfactant contains at least one alkali triglycol cholesterol in a concentration of 1-20% by weight in the mixture. 3. The process according to claim 1 or 2, wherein the alkyl group of the triglycol glycol ether is a straight or branched chain having from 3 to 6 carbon atoms. A process according to any one of the preceding claims, characterized in that the alkyl group of the alkyltriglycol ether has from 3 to 5 carbon atoms. Process according to any one of the preceding claims, characterized in that the alkyltriglycol ether is n-butyltriglycol ether (also known as triethylene glycol mono-n-butyl ether). A process according to any one of the preceding claims, characterized in that the surfactant is a by-product stream of the glycol ether production process containing a high proportion of n-butyl triglycol ether. 7. The process of claim 6, wherein the by-product stream comprises 75% by weight of n-butyl triglycol ether, 2.5% by weight of butyldiglycol ether, 19% by weight of butyl tetraglycol ether and 2% by weight of butyl pentaglycol cholesterol. 8. A process according to any one of the preceding claims, wherein the extractive chemical is present in an amount of 1-25% by weight, based on the total mixture. A process according to any one of the preceding claims, characterized in that the mixture is introduced into the rock structure in the form of a preformed homogeneous composition; said mixture being an aqueous solution containing two components in a ratio such that the homogeneity of the mixture is maintained. A process according to any one of the preceding claims, characterized in that said mixture is a homogeneous mixture containing an aqueous medium, (a) at least one surfactant containing from 1 to 20% by weight of n-butyltriglycol ether and (b) at least one chemical for the production of aba gas oil, a plaque inhibitor in an amount of 1-25% by weight. 11. The method of claim 5, wherein the oil or gas extraction chemical, a plaque inhibitor and a surfactant, is embedded in the oil and / or gas-containing rock, downstream of the production well and then pre-prepared by said extraction chemical into the rock structure. and a homogeneous mixture of surfactant. A process according to any one of the preceding claims, characterized in that the mixture is a preformulated unitary composition containing an alkyl triglycol cholether and at least one extraction chemical, a plaque inhibitor, which maintains the mixture in a clean and stable manner at ambient temperature to at least 45 ° C. . A process according to any one of the preceding claims, characterized in that said mixture additionally contains other components, including (i) other extraction chemicals or (ii) co-solvents, which ensure the stability of the mixture in relatively higher concentrations or when the surfactant is present. is used in the upper quadrant of the stated range and the mixture is substantially free of water immiscible components. 14. A process according to claim 12 wherein the total solvent is a lower aliphatic alcohol selected from methanol and ethanol. A process according to any one of claims 1 to 8, characterized in that each component of the mixture, when inserted sequentially into the rock structure, is in homogeneous form, used in its undiluted form or in aqueous solution. Process according to any one of the preceding claims, characterized in that the aqueous medium of the mixture is fresh, tap, river, sea, industrial or rock water having a total salinity of 0-250 g / l and a pH of 0.5-9. The process according to any one of the preceding claims, characterized in that the aqueous medium used in the aqueous medium and the mixture has an acidic pH in the range of 0.16.0. A process according to any one of the preceding claims, characterized in that the oil or gas extraction chemical is an anti-plaque inhibitor effective in inhibiting the formation of calcium and / or barium deposits. A process according to claim 17 or 18, characterized in that it is a. In that the plaque inhibitor is a water-soluble organic molecule having at least 2 carboxylic and / or phosphonic acid and / or sulfuric acid groups. 20. The method of claim 17 or 18, wherein the plaque inhibitor is a monomer, oligomer or polymer having at least one hydroxyl group and / or an amino nitrogen atom. 21. The method of claim 19, wherein the plaque inhibitor is an aliphatic phosphonic acid having from 2 to 50 carbon atoms or an aminoalkyl phosphonic acid each bearing at least one methylenephosphonic acid group. 22. The method of claim 21, wherein the plaque inhibitor is selected from the group consisting of ethylenediamine tetra (methylene phosphonate), diethylenetriamine penta (methylene phosphonate), and triamine and tetraminopolymethylenephosphonates with 2-4 methylene groups between each N atom. 23. The method of claim 19, wherein the plaque inhibitor is a polycarboxylic acid selected from lactic, tartaric and poly (meth) acrylic acids. A process according to any one of the preceding claims, wherein the other mining chemical in the mixture is an inhibitor: (i) corrosion, (ii) gas hydrate formation, (iii) wax, or (iv) asphaltene precipitate; or, is a hydrogen sulfide acceptor or wax dispersant.