TWI505869B - Apparatus, system and method for emulsifying oil and water - Google Patents

Description

Emulsified oil and water device, system and method

The present invention relates to an apparatus, system and method for emulsifying oil and water, which are particularly suitable for preparing an aqueous emulsion of a sizing agent for sizing or surface sizing of paper and paperboard or for treating paper and Reverse phase of the inverse emulsion polymerization product of paperboard.

An additive used in the paper industry to impart resistance to water-permeable properties is known as a sizing agent. The two most common synthetic sizing agents are alkyl ketene dimers (AKD) and alkenyl succinic anhydrides (ASA).

AKD and ASA are hydrophobic water-insoluble substances. These materials may be added to the pulp prior to the formation of the thin layer (referred to as internal sizing) or may be applied to the surface of the formed web (referred to as surface sizing). For any application, the sizing agent should be well distributed in the aqueous system to be effective. Therefore, the water insoluble additives are usually added in the form of an aqueous oil-in-water emulsion.

The aqueous emulsions of the sizing agent can be supplied to the paper mill in this form or can be produced immediately. In fact, it is advantageous to have some synthetic cellulose reactive sizing agents ready for emulsification. After emulsification with water, the ASA is, for example, emulsified immediately due to the instability of the anhydride functional groups.

Currently, two types of factory-based emulsification techniques are used in the relevant industries: (1) high shear, and (2) low shear. High shear emulsification requires the passage of ASA (or other sizing agent) and protective colloid, starch or synthetic polymer through a high shear turbopump or homogenizer with or without the addition of a surfactant. A limitation of this method is the need to "apply a high homogenization shear and/or pressure, along with a rigid step associated with the emulsification ratio, temperature, etc., to produce a relatively stable, stable emulsion of a particular sizing agent, Expensive and heavy equipment" (US Patent No. 4,040,900).

In order to solve the limitation of high shear emulsification, in 1977, a low shear emulsification method was proposed by Mazzarella (U.S. Patent No. 4,040,900), and Mazzarella revealed that there are 3 to 20 parts by weight of surface active additive (surfactant). A mixture of ASAs that "use water in the absence of high shear forces and is easily emulsified by agitating, passing through a mixing valve or a conventional aspirator at atmospheric pressure". Unfortunately, this low shear emulsification can cause foam problems and poor sizing efficiency because the increase in surfactant concentration causes the surfactant to accumulate in the system. (C. E. Farley and R. B. Wasser, "Sizing with Alkenyl Succinic Anhydride", The Sizing of Paper, Chapter 3, 2nd Edition, edited by W. F. Reynolds, Tappi Press, 1989, pp. 51-62).

Recently, Pawlowska et al. (WO 2006/096216) discloses an improved method of sizing paper at the wet end, which uses a relatively simple and relatively inexpensive low shear device for ASA emulsification. Pawlowska et al. disclose a sizing process which comprises "forming an aqueous sizing emulsion comprising an alkenyl succinic anhydride component in the absence of high shear forces" which is post-diluted by a cationic component. The main difference between Pawlowska and Mazzarella is the subsequent dilution of the emulsion by the cationic component to improve retention. The examples consistently show that low shear ASA emulsions diluted after cationic starch are less efficient than high shear ASA emulsions. However, it is believed that the ease of the emulsification process for low shear ASA emulsions gives papermakers "operational and cost effective "."

Other patents disclose the use of modified starches (e.g., US 6,210,475) or polymers (e.g., US 6,444,024 B1) to enhance the performance of low shear emulsification systems, however, none of them can address the basic properties of the low shear system characteristics. And the issue of operability.

The definition of "high shear" conditions for ASA emulsification in the literature tends to be qualitative. A series of devices that meet or do not meet the stated specifications are generally used. The "High Shear" system is: "stored in Waring blenders, turbo pumps, or other very high speed mixers, etc." and "stored in pistons or other types of homogenizing equipment." (Mazzarella). The "low shear" system is: "mixed only by mixing valve or conventional aspirator or by general agitation in a storage preparation system" (Mazzarella), or "by selection from a centrifugal pump, static A combination of a hybrid mixer, a peristaltic pump, and a combination thereof produces a shear condition (Pawlowska). However, in commercials including industrial low and high pressure devices such as Cytec low pressure turbine emulsifiers, Nalco high pressure emulsifier systems, and National Starch turbine and venturi emulsifiers supplied by Cytec Industries, Inc. In the list of emulsification equipment, these definitions become confusing, showing the presence of a turbo pump that meets the low shear category. In addition, Weilin's blenders can produce both low and high energy ASA emulsions by varying the voltage (Chen and Woodward, Tappi J. August 1986, p. 95). Therefore, the "low cut" and "high cut" systems cannot be defined simply by device type.

In the "Principles of ASA Sizing" (CE Farley, 1987 Tappi Sizing Short Course, page 89), there are more quantitative definitions of the "high shear" and "low shear" emulsion systems. "High shear emulsification is accomplished using a precision tolerance turbopump. The pump is operated with a pressure difference between pump outlet and inlet of approximately 120 to 140 psi (8.3 to 9.7 bar). ASA and starch are tied to The turbine pump is mixed at or near the inlet." "In low shear emulsification, ASA, starch and surfactant are mixed and passed through a series of venturis. Starch: ASA: general ratio of surfactants It is about 2.5:1:0.05. One potential disadvantage of this method is the higher concentration of surfactant used, which can lead to "degumming" and poor ASA efficiency and foam problems." Thus, Farley's distinction between high shear and low shear is that the high shear system has a pressure differential of about 120 to 140 psi (8.3 to 9.7 bar).

Similarly, Dilts et al. (US 2008/0277084 A1) defines low shear as the ability to pump liquid through a pump having a back pressure of 50 psi (3.4 bar) or less, however, the high shear system is defined as requiring 150 to A back pressure of 300 psi (10.3 to 20.7 bar) is used to pump the liquid.

There is still a need in the market for equipment that does not suffer from paper machine runnability (foam, deposition) and/or simpler and less expensive equipment for ASA emulsification due to high surfactant loading or poor emulsion quality.

It has been found that good quality in water can be achieved by feeding water through a venturi device at relatively high pressure and introducing the sizing agent to the venturi suction port to achieve good paper machine operability and good sizing efficiency. An emulsion of a stable sizing agent such as ASA. This system is simpler, more reliable, more energy efficient, and less expensive than the conventional high shear systems currently in use, and can provide better surfactant levels than currently available low shear, low energy systems. Quality emulsion. In addition, this system can be used for factory-type emulsification of other papermaking additives, or for the reverse phase of inverse emulsion polymerization products.

In a first aspect, the system for emulsifying an oil-in-water or water-in-oil comprises a venturi device. The continuous phase is introduced into the venturi apparatus under pressure and introduced into the mixing section through a continuous phase nozzle of a first diameter. The dispersed phase is introduced into the mixing section of the venturi apparatus to form an emulsion of the dispersed phase in the continuous phase. The emulsion passes through a mixed phase nozzle having a second diameter and is directed to the outlet of the venturi device. The mixed phase nozzle diameter is greater than the continuous phase nozzle diameter by a ratio greater than 1:1 and less than 4:1.

Preferably, the continuous phase comprises water which is introduced at a pressure of from about 10 to about 50 bar and a flow rate of from about 10 to 100 m/s. Preferably, the dispersed phase comprises one or more sizing agents. The emulsion can be discharged into a discharge chamber in which the optional additive can be mixed. The emulsion can be stored for later use, or it can be diluted with water or other aqueous solution prior to addition to the wet end, or to a size press or coater of a paper or paperboard system. Alternatively, the emulsion can be added directly to the wet end, or a size press or coater of a paper or board system.

The dispersed phase can comprise one or a mixture of a cellulose reactive paper sizing compound or a cellulose non-reactive paper sizing compound. Exemplary cellulose reactive paper sizing compounds include alkenyl succinic anhydride (ASA), ketene dimers and polymers (such as alkyl ketene dimers (AKD)), containing from about 12 to 22 carbons An organic epoxide of an atom, a fluorenyl halide having from about 12 to about 22 carbon atoms, a fatty acid anhydride derived from a fatty acid having from about 12 to about 22 carbon atoms, and an organic isocyanate having from about 12 to about 22 carbon atoms.

The dispersed phase can be introduced into the venturi device only by suction at the suction port, or can be pumped into the mixing section using a pump. Preferably, the dispersed phase is filtered prior to introduction into the mixing section.

Alternatively, the continuous phase can be water and the dispersed phase can be an inverse emulsion polymer commonly used in papermaking. In this case, a water-in-oil emulsion containing the polymer in the aqueous phase can be introduced into the venturi device through the suction port. The presence of a large amount of dilution water and the mixing in the mixing section of the destructible emulsion "activates" the polymer to produce a dilute polymer mixture comprising oil droplets. One example of an inverse emulsion polymer commonly used in papermaking is retention and drainage aids such as PERFORM SP7200 or PERFORM PC8179 retention and drainage aids (Ashland Inc., Covington, KY).

In a second aspect, a method of emulsifying a sizing agent for treating paper or paperboard has the following steps. The continuous phase is introduced under pressure into the venturi apparatus and directed to a continuous phase nozzle having a first diameter that can be introduced into the mixing section of the apparatus. A dispersed phase is introduced into the mixing section of the venturi apparatus to form an emulsion of the dispersed phase in the continuous phase. The emulsion is directed through a mixed phase nozzle having a second diameter d2 that is greater than the continuous phase nozzle diameter d1 by a ratio greater than 1:1 and less than 4:1. Preferably, the continuous phase is introduced at a pressure of from about 10 bar to about 50 bar and has a flow rate of from about 10 to 100 m/s in the continuous phase nozzle.

In this method, the dispersed phase can comprise one or a mixture of a cellulose reactive paper sizing compound or a cellulose non-reactive paper sizing compound. Exemplary cellulose reactive paper sizing compounds include alkenyl succinic anhydride (ASA), ketene dimers and polymers, organic epoxides having from about 12 to about 22 carbon atoms, and from about 12 to about 22 A mercapto halide of a carbon atom, a fatty acid anhydride derived from a fatty acid having from about 12 to 22 carbon atoms, and an organic isocyanate having from about 12 to about 22 carbon atoms.

In this method, the dispersed phase can be introduced to the venturi device only by suction at the suction port, or can be pumped into the mixing section using a pump. Preferably, the dispersed phase is filtered prior to introduction into the mixing section.

The emulsion of the resulting sizing agent has a thickness of about 2 microns or less, preferably between 0.5 and 1.5 microns, as measured by light scattering techniques on the emulsion sample within about 1 to about 10 minutes after the emulsion leaves the venturi device. Between the best, the average particle size is below about 1 micron. The emulsion is added to the wet end or to a size press or coater added to a paper or board system. If the continuous phase is water, the emulsion is preferably diluted by water to provide a solids content in the range of from about 1 to about 5 weight percent. The post-diluted emulsion is then preferably mixed with an aqueous solution of a natural or synthetic cationic polymer prior to being added to the wet end, size press or coater.

In another aspect, the venturi device has a first diameter continuous phase nozzle that directs the first liquid under pressure into the mixing section; and a second liquid introduced into the mixing section to form an emulsion therein Entrance. The venturi apparatus further includes a mixed phase nozzle having a second diameter through which the emulsion is directed to the outlet of the venturi apparatus. The mixed phase nozzle diameter is greater than the continuous phase nozzle diameter by a ratio greater than 1:1 and less than 4:1. Preferably, the mixing section is tapered from the widest diameter at the inlet of the mixing section to the narrowest diameter at the mixing phase nozzle of the mixing section. Preferably, the venturi device includes an exhaust diffuser in fluid communication with the mixed phase nozzle and located at the exit of the venturi device.

In this application, "emulsion" is a mixture of liquid particles in a second liquid. Two conventional types of emulsions are oil-in-water and water-in-oil. "Oil" generally means a water-insoluble or approximately water-insoluble liquid. In the case of oil-in-water emulsions, water is the "continuous phase" and the oil is the discontinuous phase. In the case of water-in-oil emulsions, the opposite is true. Herein, the liquid forming the continuous phase of the final emulsion is referred to as the "continuous phase" and the other liquid forming the discontinuous phase of the final emulsion is referred to as the "dispersed phase". In the case of an oil-in-water emulsion, water is the continuous phase and the oil is the dispersed phase.

A schematic of a system 10 for emulsifying oil and water is shown in FIG. The system 10 will be described with reference to emulsification of a sizing agent such as an alkyl ketene dimer (AKD) or an alkenyl succinic anhydride (ASA) in water. However, it should be understood that the system can be used to emulsify other materials, and the choice of continuous and dispersed phases is for illustrative purposes and is not intended to limit the invention.

Referring to Figure 1, a "continuous phase" (such as, but not limited to, water in this embodiment) supplied from a sump or supply sump 12 is passed through control valve 18 and flow meter 20 via line 14 and filter 16. Feed to pump 22 . The flow rate of water, which may alternatively be referred to as "continuous phase" with this embodiment, is controlled at a particular feed rate using a control loop having a flow meter 20 and a control valve 18 . It is possible for those skilled in the art to utilize other flow control methods. The pump 22 can be any of a variety of pumps including a multi-stage centrifugal pump or a regenerative pump that can deliver a feed pressure of about 30 bar, or a feed pressure in the range of about 10 to 50 bar, more preferably about 18 to 35 bar. . Pressure gauges 40b , 40a , 40c are provided to monitor the pressure of the continuous phase, the dispersed phase, and the emulsion. The continuous phase is delivered to the first inlet 48 of the venturi device 50 (see Figure 3).

The "dispersed phase" from the sump or supply reservoir 32 (such as, but not limited to, the liquid sizing agent in this embodiment) passes through the flow meter 39 and the back pressure regulator 42 via line 34 and filter 36 . Feed (or pumped by pump 38 ) to the suction port 52 of the venturi device 50 (see Figure 3). The filter 36 is sized to avoid clogging of the mixed phase nozzle 60 of the venturi device 50 . For details of the venturi device 50 , reference may be made to Figures 2 to 4.

Pump 38 may be selected to be any of a variety of types of pumps that can deliver feed pressures up to about 5 bar, preferably, for example, about 3 bar. The flow rate of the sizing agent, which may also be referred to as the "dispersed phase" in this embodiment, may be controlled by pump 38 or by a control loop. Alternative controls may also be provided to set the ratio of continuous relative dispersed phases fed to the venturi device 50 . Since the continuous phase fed to the venturi device 50 creates a vacuum at the dispersed phase suction port 52 , a pump 38 is not required to feed the dispersed phase to the venturi device 50 . However, the use of pump 38 to feed the dispersed phase to venturi device 50 produces a more stable feed pressure and provides better control during the emulsion formation process.

The continuous and dispersed phases are mixed in the venturi apparatus 50 and discharged to the chamber 70 . Chamber 70 has a diameter sufficient to reduce the velocity of the emulsified product from venturi device 50 . The additive can be mixed with the emulsified product in chamber 70 or downstream of chamber 70 .

The mixed phase or emulsified product can be directed to a paper machine or can be directed through a pressure control valve 74 to a hopper 76 or shipping container (not shown). If the continuous phase is water, the emulsion is preferably diluted with water to produce a solids content ranging from about 1 to about 5 weight percent. The post-diluted emulsion is then preferably mixed with an aqueous solution of a natural or synthetic cationic polymer prior to addition to the wet end, paper or (plate) machine size press or coater.

One embodiment of a venturi apparatus 50 for emulsifying oil and water is shown in Figures 2 through 4. 3 is a longitudinal sectional view of the venturi apparatus 50 . The venturi device 50 has a first inlet 48 into which a continuous phase, such as water, can be introduced. The continuous phase flows through the venturi device 50 in the direction of arrow 54 . The continuous phase flow rate increases as it enters the smaller diameter passage 56 from the first inlet 48 and into the tapered section 58 and then enters the minimum diameter nozzle or continuous phase nozzle 66 . The shape and size of the continuous phase flow passage can be varied.

The venturi device 50 has a suction port 52 through which a dispersed phase, such as, but not limited to, a sizing agent, enters the venturi device 50 in the direction of arrow 62 . A vacuum is created at the suction port 52 by the continuous phase flow through the continuous phase nozzle 66 .

The continuous phase (e.g., water) and the dispersed phase (e.g., sizing agent) are mixed in a generally conical chamber 80 and into the mixed phase nozzle 60 . In the present invention, the mixed phase nozzle diameter d2 is greater than the continuous phase nozzle diameter d1 by a ratio greater than 1:1 and less than 4:1. In one embodiment of the present invention, with reference to FIG. 4, the mixed phase nozzle 60 having a diameter d2 d1 66 a continuous phase of the nozzle diameter of twice as large. The continuous phase and the dispersed phase are mixed by turbulent flow in a conical mixing chamber 80 between the continuous phase nozzle 66 and the mixed phase nozzle 60 to form an emulsion or mixed phase. The emulsion exits the mixed phase nozzle 60 through the discharge diffuser 82 and exits the venturi device in the direction of arrow 84 . The emulsion thus formed is discharged into the chamber 70 (see Fig. 1).

In the present invention, the emulsion is formed by feeding the continuous phase of the emulsion through the continuous phase nozzle 66 under high pressure. The continuous phase flows through the continuous phase nozzle 66 to the dispersed phase inlet 52 of the venturi apparatus 50 to create a low pressure region. The mixture is continuously mixed with the dispersed phase in a substantially conical mixing chamber 80 inside the venturi apparatus 50 and fed to a mixed phase nozzle 60 having a diameter d2 greater than the diameter d1 of the continuous phase nozzle 66 . The two different diameter dimensions d2 , d1 are produced in two spray layers at high speed. The emulsified product from the venturi device 50 is discharged into the chamber 70 where the pressure and fluid velocity are reduced. 70 or downstream of the chamber 70, may be added to other reagents in the chamber to improve the emulsion properties of the emulsion or the emulsion can be diluted with water and / or an aqueous solution by a cationic polymer, emulsion, or other modification may be made. Figure 1 further shows the selected tank 76 in which the emulsion can be stored.

A representative venturi device 50 has the following dimensions. Referring to Figure 4, the mixed phase nozzle 60 has a circular diameter d2 of about 1.2 mm and the continuous phase nozzle 66 has a circular diameter d1 of about 0.7 mm. In a selection device, the mixed phase nozzle 60 has a circular diameter d2 of about 1.8 mm and the continuous phase nozzle 66 has a circular diameter d1 of about 1 mm. Referring to Figure 3, the representative venturi device 50 has an overall length of about 90 mm. The first inlet 48 is formed as a female threaded circular opening having a diameter of about 12.7 mm (0.5 inches) to receive a feed tube or pipe joint (not shown) for introducing a continuous phase into the first inlet 48 . The first inlet 48 has a length of about 20 mm, and the smaller diameter passage 56 has a length of about 35 mm, and the tip forms a cone to introduce the continuous phase liquid into the continuous phase nozzle 66 . The continuous phase nozzle 66 has a length of about 4 mm. The mixed phase nozzle 60 has a length of about 15 mm.

The suction port 52 in the representative venturi device 50 has a circular diameter of about 10 mm and a length of about 10 mm. The suction port 52 is tapered to a tapered end which directs the dispersed phase material into a conduit leading to the conical chamber 80 for mixing the continuous phase with the dispersed phase to form an emulsion or mixed phase. The tapered chamber 80 has a circular proximal diameter of about 10 mm and tapers towards the mixed phase nozzle 60 at its end.

The discharge diffuser 82 at the end of a representative venturi device 50 in accordance with the present invention is formed to have an externally threaded outer portion of about 12.7 mm (0.5 inch) for engagement with a threaded discharge tube or fitting (not shown) The mixed phase (emulsion) is removed from the venturi device 50 . The discharge diffuser has a length of about 18 mm and the outer circular opening has a diameter of about 15 mm. An end view of the venturi device 50 from the discharge diffuser 82 of Figure 2 shows that the venturi device 50 has a generally hexagonal or hexagonal exterior with a height and width of about 36 mm.

A representative venturi device 50 is shown in Fig. 3, which is constructed of two machined parts, wherein a first inlet 48 leading to the venturi nozzle 66 is formed in the first component and a suction port is formed in the second component. 52 , tapered chamber 80 , mixed phase nozzle 60 and diffuser 82 . The first component engages the second component and is connected by a thread 77 formed on the exterior of the first component and the interior of the second component. A seal ring 78 is provided for fluid tight sealing of the first component and the second component.

The continuous phase of the emulsion can be water based or oil based. When the continuous phase is water based, the dispersed phase of the emulsion can be oil based. When the continuous phase is an oil base, the dispersed phase of the emulsion can be water based. Examples of continuous water-based phases include, but are not limited to, water, aqueous starch solutions, and polymer solutions. Other ingredients commonly used in emulsions of sizing agents such as, but not limited to, biocides, alum, cationic resins, surfactants, and the like, can be included in the continuous phase feed. Examples of dispersed oil phases include, but are not limited to, ASA, AKD, and polymers. Additives such as surfactants may optionally be included in the oil phase.

The feed pressure of the continuous phase is between about 10 and 50 bar, preferably between about 18 and 35 bar. The ratio of the size of the mixed phase nozzle to the size of the continuous phase nozzle is greater than 1:1 and less than 4:1, preferably between 1.5:1 and 2.5:1. The diameter of the continuous phase nozzle (e.g., nozzle 66 in Figure 3) is set to achieve a flow rate of from about 10 to 100 m/s, preferably from about 40 to 60 m/s. High speed creates the conditions for instant formation of the emulsion.

The ratio of the continuous relative dispersed phase is varied to meet the emulsion's requirements for viscosity, stability, and uniformity. The concentration of the dispersed phase in the continuous phase is from about 2 to 50% by weight, preferably from about 4 to 35% by weight. The chamber located at the discharge port of the venturi device (e.g., chamber 70 in Fig. 1) has a diameter that is about 5 to 100 times the diameter of the continuous phase venturi device nozzle (e.g., nozzle 66 in Fig. 3). Preferably, the diameter of the continuous phase nozzle 66 is about 40 to 80 times. The pressure in the chamber (e.g., chamber 70 in Figure 1) is from about 1 to 6.7 bar, preferably from about 1.3 to 5 bar. The dispersed phase feed pressure is from about 1.3 to 6.7 bar, preferably from about 3 to 4.3 bar.

Preferred paper sizing compounds for use in the dispersed phase of the present invention are selected from the group consisting of cellulose reactive paper sizing compounds and cellulose non-reactive paper sizing compounds. For the purposes of the present invention, cellulose reactive sizing agents are defined as sizing agents which form covalent chemical bonds by reaction with hydroxyl groups of cellulose, and definition of cellulose non-reactive sizing agents. For those who are unable to form such covalent bonds with cellulose.

Preferred cellulose reactive sizing agents for use in the present invention include alkenyl succinic anhydride (ASA), ketene dimers and polymers, organic epoxides having from about 12 to about 22 carbon atoms, containing about 12 A mercapto halide of up to 22 carbon atoms, a fatty acid anhydride derived from a fatty acid having from about 12 to 22 carbon atoms, and an organic isocyanate containing from about 12 to about 22 carbon atoms. Mixtures of reactive sizing agents can also be used.

Alkenyl succinic anhydride (ASA) is composed of an unsaturated hydrocarbon chain containing pendant succinic anhydride groups. These are usually prepared in a two-step process starting from alpha olefins. The olefin is first isomerized by randomly moving the double bond from the alpha position. In a second step, the isomerized olefin is reacted with maleic anhydride to give the final ASA as in Formula (1) (see below). Typical olefins useful for reaction with maleic anhydride include alkenyl, cycloalkenyl and aralkenyl compounds containing from about 8 to about 22 carbon atoms. Specific examples are isooctadecenyl succinic anhydride, n-octadecyl succinic anhydride, n-hexadecenyl succinic anhydride, n-dodecyl succinic anhydride, isododecyl succinic anhydride, n-decenyl succinic anhydride And n-octenyl succinic anhydride.

The alkenyl succinic anhydrides are disclosed in U.S. Patent No. 4,040,900, the disclosure of which is incorporated herein in its entirety by reference in its entirety in the the the the the the the the Year, pages 51-62. A variety of alkenyl succinic anhydrides are commercially available from Bercen, Inc. (Denham Springs, LA). The alkenyl succinic anhydride used in the present invention is preferably liquid at 25 °C. More preferably, it is equal to a liquid state at 20 °C.

Preferred ketene dimers and polymers are those of the formula (2) (see below) wherein n is an integer from 0 to about 20, and the same or different R and R" are from 6 to 24 carbons. A saturated or unsaturated, linear or branched alkyl or alkenyl group; and R' is a saturated or unsaturated, straight or branched alkylene group having from about 2 to about 40 carbon atoms.

The ketene dimer which can be used as the dispersed phase in the process of the present invention has the structure of the formula (2) wherein n = 0 and the same or different R and R" groups are hydrocarbyl groups. Preferably, these are The R and R" groups are a linear or branched alkyl or alkenyl group having 6 to 24 carbon atoms, a cycloalkyl group having at least 6 carbon atoms, an aryl group having at least 6 carbon atoms, having at least 7 An aralkyl group of carbon atoms, an alkylaryl group having at least 7 carbon atoms, and a mixture thereof. More preferably, the ketene dimer is selected from the group consisting of: (a) octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl , a behenyl, tetracosyl, phenyl, benzyl, β-naphthyl, and cyclohexyl ketene dimer, and (b) are prepared from an organic acid selected from the group consisting of Ketone dimer: octadecanoic acid, naphthenic acid, 9,10-decenoic acid, 9,10-dodecenoic acid, palmitoleic acid, oleic acid, ricinoleic acid, linoleic acid, tungstic acid, Naturally occurring in coconut oil, babassu oil, palm kernel oil, palm oil, olive oil, peanut oil, rapeseed oil, butter, lard, whale fat, and the above-mentioned fatty acids. Any mixture with each other. Most preferably, the ketene dimer is selected from the group consisting of octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, twentieth Dialkyl, tetracosyl, phenyl, benzyl, β-naphthyl, and cyclohexyl ketene dimers.

Alkyl ketene dimers have been used commercially for many years and are prepared by dimerizing alkyl ketenes prepared from saturated linear fatty acid chlorides; the most widely used are palmitic acid and/or hard Made with fatty acid. The pure alkyl ketene dimer can be obtained from Ashland Hercules Water Technologies, Ashland Inc, (Wilmington, Del.) using AQUAPEL 364 sizing agent.

Preferred ketene polymers for use as a dispersed phase in the process of the invention have the formula (2) wherein n is an integer of at least 1, and the same or different R and R" are from 6 to 24 carbon atoms, a saturated or unsaturated linear or branched alkyl or alkenyl group of preferably 10 to 20 carbon atoms, and more preferably 14 to 16 carbon atoms, and R' has 2 to 40 carbon atoms, preferably 4 to A saturated or unsaturated linear or branched alkyl group of 8 or 28 to 40 carbon atoms.

The preferred ketene multimers are described in the following: European Patent Application Publication No. 0 629 741 A1, and U.S. Patent Nos. 5,685, 815 and 5, 846, 663, the entire contents of each of which are incorporated herein by reference.

Preferred ketene dimers and polymers which can be used as the dispersed phase in the present invention are non-solid at 25 ° C (substantially amorphous, semi-crystalline or waxy solid; that is, they are equivalent to flow during heating) The other one without melting heat. The non-solid ketene dimers and polymers at 25 ° C are disclosed in U.S. Patent Nos. 5,685,815, 5,846,663, 5, 725, 731, 5, 766, 417, and 5, 879, 814, the entireties of each of which are incorporated herein by reference. Non-solid ketene dimers at 25 ° C are available from Ashland Hercules Water Technologies (Wilmington, Del) with PREQUEL and PRECIS sizing agents.

Other preferred cellulosic reactive sizing agents which can be used as the dispersed phase in the present invention are mixtures of ketene dimers or polymers with alkenyl succinic anhydrides as described in U.S. Patent No. 5,766,417. The entire text is incorporated herein by reference.

The cellulose non-reactive sizing agent used as the dispersed phase in the present invention preferably comprises a hydrophobic substance which is free flowing at a temperature lower than 95 ° C, preferably lower than 70 ° C, for example, wax, rosin ester, carbon Hydrogen resin or terpene resin and polymeric sizing agent.

The sizing emulsion of the present invention may also suitably comprise at least one surfactant which promotes its emulsification in water; such materials are known in the art. In the case of an emulsion, the surfactant component promotes emulsification of the sizing agent by the water component. Generally, the surfactants are anionic or nonionic or cationic and can have a wide range of HLB values.

Suitable surfactants include, but are not limited to, phosphorylated ethoxylates which may include alkyl, aryl, aralkyl or alkenyl hydrocarbon substituents, such as those obtained from sulfonated fatty alcohols or aromatics. Ethoxylated alkylphenols (such as nonylphenoxypolyethoxyethanol and octylphenoxypolyethoxyethanol), polyethylene glycol (such as PEG 400 monooleic acid) Ester and PEG 600 dilaurate), ethoxylated phosphate, dialkyl sulfosuccinate (such as sodium dioctyl sulfosuccinate), polyoxyalkylene alkyl or polyoxyalkylene Alkyl aryl ethers or corresponding mono- or diesters, and trialkylamines and their acids and fourth salts, and amine hydrates such as oleyldimethylamine and stearyl dimethylamine.

Preferred surfactants are emulsifiable sizing agents which give them a minimum median emulsion droplet diameter or particle size. The emulsions may have a median emulsion droplet diameter or particle size of about 2 microns or less, preferably between 0.5 and 1.5 microns, and most preferably about 1 micron or less. Droplet size is conveniently accomplished by many conventional particle size measurement techniques (eg, microscopy, typical and quasi-elastic light scattering, sedimentation, disk centrifugation, electrozone induction, sedimentation field flow fractionation, and chromatography). Any one of them is measured. Suitably, the droplet size can be estimated by light scattering using an instrument such as the HORIBA LA-300 Particle Size Analyzer.

Of course, as will be appreciated by those skilled in the art, the amount of surfactant can vary depending upon the particular surfactant or mixture of surfactants employed. The amount of surfactant present in the sizing composition of the present invention should not exceed about 2 microns or less, preferably between 0.5 and 1.5 microns, and most preferably about 1 micron or less, in the resulting emulsion. The minimum value required for the value granularity. Higher amounts can result in particle size degradation and machine runnability problems caused by low quality emulsions. Surfactants may be used in an amount of from about 0.01% to about 10% by weight, based on the total weight of the sizing agent present. Preferably, the amount of surfactant present in the sizing composition is from about 0.1% to about 5% by weight. Most preferably, the amount of surfactant present in the sizing composition is less than about 1.0% by weight. Commercially available mixtures comprising at least one sizing agent and at least one surfactant, such as PREQUEL 20F or PREQUEL 90F sizing agents from Ashland Inc., Wilmington, Del., may conveniently be used to form the sizing of the present invention. Emulsion.

In the case of oil-in-water emulsions (such as emulsions of sizing agents), the continuous phase can be water or an aqueous solution of a natural or synthetic polymer. Water is preferred. If the continuous phase is water, it is recommended to dilute the emulsion with water to achieve the desired solids content, followed by further dilution with an aqueous solution of natural or synthetic polymer. Cationic polymers suitable for use in forming oil-in-water emulsions of sizing agents include any water-soluble nitrogen-containing cationic polymer that imparts a positive charge to the surface of the dispersed phase particles of the emulsion. The cationic polymers are generally quaternary ammonium compounds; homopolymers or copolymers of ethylenically unsaturated amines; epihalohydrin and polyamine polyamines, alkylene polyamines, poly(diallylamines) , bis-aminopropylpiperazine, dicyanamide (or cyanamide)-polyalkylene polyamine condensate, dicyanamide (or cyanamide)-formaldehyde condensate, and dicyanamide (or cyanamide) a resin-based reaction product of a bis-aminopropylpiperazine condensate; and a cationic starch. Cationic starch is a water soluble starch comprising an amine group, a quaternary ammonium or other cationic group which is sufficient to impart substantial cellulose to the starch as a whole. Cationic starch is preferred. Non-cationic polymers can also be used.

The use of a cationic polymer in a sizing composition is generally described in U.S. Patent Nos. 4,240,935, 4, 243, 481, 4, 279, 794, 4, 295, 931, 4, 317, 756, 4, 522, 686 to U.S. Patent No. 2,961,366 issued to Weisgerber, and U.S. Patent No. 5,853,542 (Bottorff). Amphoteric polymers can also be used, such as those disclosed in U.S. Patent No. 7,270,727 (Varnell). The entire contents of each of these patents are incorporated herein by reference.

The minimum amount of cationic polymer used should be sufficient to impart cationicity to the dispersion. The amount used can vary depending on the water solubility and cation strength of the particular polymer used, as well as other variables such as water quality.

The amount of natural or synthetic polymer can be expressed as a percentage of the weight of the cellulose reactive sizing agent used. Preferably, the polymer is from about 0.1 to about 400% by weight based on the weight of the cellulose reactive sizing agent, more preferably from about 2 to about 100% by weight based on the weight of the cellulose reactive sizing agent, and most preferably cellulose. The reactive size of the sizing agent is from about 10 to about 30% by weight. This amount will vary depending on the requirements of the particular paper application.

The temperature of the aqueous solution used for post-dilution is generally less than about 50 ° C, but it can be higher depending on the application. The pH of the aqueous solution varies depending on the application. The pH can be from about 4 to about 8. Post-dilution is typically carried out under low shear conditions (e.g., such shearing conditions as produced by devices such as centrifugal pumps, static in-line mixers, peristaltic pumps, overhead stirrers, or combinations thereof).

The sizing agent emulsion prepared according to the present invention can be used for sizing in paper or paperboard, wherein the sizing emulsion is added to the pulp in the wet end of the papermaking process, or used for surface sizing of paper or paperboard, wherein The gum dispersion is applied to a size press or coater. The invention may also be used in one or both components of a two component sizing system. For example, one component can be mixed internally with the wood pulp and the second component can be applied to a size press (general practice of papermaking).

The amount of the sizing agent added to the raw material or applied as a surface sizing agent is from about 0.005 to 5% by weight, and preferably from 0.01 to 1% by weight, based on the dry content of the raw material (ie, the fiber and the optional filler), wherein The dosage depends primarily on the quality of the pulp or paper to be sized, the sizing compound used and the level of sizing desired.

Chemicals (such as processing aids (eg retention aids, drainage aids, contaminant control additives, etc.) or other functional additives (such as wet or dry strength additives, dyes, fluorescent) that are added to the raw materials of paper or paperboard Brighteners, etc.) can be used in combination with the sizing agents of the present invention.

Thus far, the invention has been described with reference to a dispersed phase which may comprise a sizing agent. Alternatively, the venturi apparatus 50 of the present invention can also be used to reduce the inverse emulsion polymer typically used in papermaking processes. Invert emulsion polymers are prepared and stabilized using surface active agents (known as surfactants). The surfactant used allows the water soluble monomer to be emulsified in the oil phase prior to polymerization and provides the resulting emulsion polymer stability. Stability, which includes anti-settling properties, minimal change in viscosity over time and in advance, not to mention the need for a stable emulsion during the polymerization process, requiring a durable emulsion to be packaged.

Inverse phase of the emulsion refers to the process prior to use wherein the phases are reversed and the polymer is released from the discontinuous phase. A large amount of aqueous solution is added to produce a continuous aqueous (aqueous) phase in which coalescence of the previously dispersed aqueous phase causes the polymer to disperse in the solution, causing the solution to stick. When a relatively large amount of water is combined with a water-in-oil emulsion by some degree of agitation or shearing, the surfactant is stabilized by adding a surfactant (referred to as "destroying agent surfactant") to the emulsion. To promote the reverse phase. The combination of these three factors (large amounts of dispersed phase, shear, and breaker surfactant) results in an inverse or reverse rotation of the emulsion. In addition, the polymer can now interact with other aqueous materials. A relatively small amount of oil (20 to 40% by weight of the initial emulsion) becomes dispersed in the aqueous phase, wherein the oil is a minor component due to the addition of a large amount of aqueous solution.

The polymer is reversed to an aqueous solution such that the resulting active polymer concentration is generally from about 0.1% to about 1.5% by weight. The concentration used will depend on a number of factors including, but not limited to, water chemistry and temperature, solution viscosity, feed rate, and equipment size and flow rate.

The emulsion polymer can be reversed to an aqueous solution by directing a converging stream of water and pure emulsion at a desired concentration through the venturi apparatus 50 . In this reverse phase, the continuous phase is water which is introduced through the first inlet 48 of the venturi apparatus 50 and the dispersed phase is an emulsion polymer or a pure emulsion which passes through the suction port of the venturi apparatus 50 . 52 introduced. The continuous phase pressure can be from about 10 to 40 bar, preferably from about 15 to 25 bar, and the continuous phase flow rate can be from about 10 to 50 m/s, preferably from about 25 to 35 m/s. The resulting mixture is then passed through a mixing stage (such as a static mixer or mechanical pump) where the mixing promotes the reverse phase process. Next, the aqueous solution is typically transferred to a storage tank where it is mixed until homogeneous. In a continuous system, the step of transferring to the sump is omitted.

Other dilution water is typically added to the reverse phase polymer solution only prior to introduction to the process to aid dispersion of the polymer.

Instance Example 1

150 l/h of water was fed as a continuous phase into a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 30 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Figure 3) is 1 mm. The PREQUEL 20F sizing agent (ASA) dispersed phase was fed at a vacuum of 15 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 2 mm. In the continuous phase nozzle, the venturi speed is 53 m/s. The emulsion has a median particle size of 0.67 microns.

Example 2

170 l/h of water was fed as a continuous phase into a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 30 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Figure 3) is 1 mm. The PREQUEL 20F sizing agent (ASA) dispersed phase was fed at a vacuum of 27 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 2 mm. In the continuous phase nozzle, the venturi speed is 60 m/s. The emulsion has a median particle size of 0.67 microns.

Example 3

80 l/h of water is fed as a continuous phase to a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 31 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Fig. 3) is 0.8 mm. The PREQUEL 20F sizing agent (ASA) dispersed phase was fed at a vacuum of 8 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 1.6 mm. In the continuous phase nozzle, the venturi speed is 44 m/s. The emulsion has a median particle size of 0.82 microns.

Example 4 (comparative)

180 l/h of water is fed as a continuous phase into a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 32 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Figure 3) is 1 mm. The PREQUEL 20F sizing agent (ASA) dispersed phase was fed at a vacuum of 15 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 1 mm (the continuous phase nozzle is the same diameter as the mixed phase nozzle). In the mixed phase nozzle, the venturi speed is 63 m/s. The emulsion is almost instantly dispersed into the separated phase: water and ASA droplets. The particle size distribution could not be measured.

Example 5

160 l/h of water was fed as a continuous phase into a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 30 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Figure 3) is 1 mm. A PREQUEL 90F sizing agent (AnKD from Ashland Hercules Water Technologies, Wilmington, Del.) was applied at a vacuum of 30 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 2 mm. In the continuous phase nozzle, the venturi speed is 57 m/s. The emulsion settled and had a median particle size of 0.8 microns.

Example 6

90 l/h of water is fed as a continuous phase to a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 30 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Fig. 3) is 0.8 mm. The Prequel 20F size (ASA) dispersed phase was fed at a vacuum of 30 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 2.4 mm. In the continuous phase nozzle, the venturi speed is 50 m/s. The emulsion was stable and had a median particle size of 1.15 microns.

Example 7

180 l/h of water is fed as a continuous phase into a first inlet such as the venturi apparatus shown in Figures 2 to 4. The water feed pressure is 30 bar. The continuous phase nozzle diameter (e.g., the diameter of the nozzle 66 in Figure 3) is 1.2 mm. The Prequel 20F size (ASA) dispersed phase was fed at a vacuum of 30 kg/h to the suction port of the venturi device. The diameter of the mixed phase nozzle (for example, the diameter of the nozzle 60 in Fig. 3) is 1.6 mm. In the continuous phase nozzle, the venturi speed is 44 m/s. The emulsion settled and had a median particle size of 0.8 microns.

While the invention has been described with respect to the specific embodiments thereof, it will be understood The scope of the appended claims and the invention are to be construed as being

10. . . system

12. . . Storage tank or supply tank

14. . . Pipeline

16. . . filter

18. . . Control valve

20. . . Flow meter

twenty two. . . Pump

32. . . Storage tank or supply tank

34. . . Pipeline

36. . . filter

38. . . Pump

39. . . Flow meter

40a, 40b, 40c. . . pressure gauge

42. . . Back pressure regulator

48. . . First entrance

50. . . Venturi device

52. . . suction point

54. . . arrow

56. . . (smaller diameter) channel

58. . . Conical section

60. . . Mixed phase nozzle

62. . . arrow

66. . . Continuous phase nozzle

70. . . room

74. . . Pressure control valve

76. . . Storage tank

77. . . Thread

78. . . Sealing ring

80. . . Conical chamber

82. . . Discharge diffuser

84. . . arrow

Other objects, advantageous features, and possible applications of the present invention are disclosed in the above description of the embodiments with reference to the following drawings, in which:

Figure 1 is a schematic illustration of an exemplary system for emulsifying oil and water in accordance with the present invention;

Figure 2 is a front elevational view of the outlet end of the venturi device in accordance with the present invention;

Figure 3 is a cross-sectional view of the venturi device taken along line 3-3 of Figure 2;

4 is an exploded cross-sectional view showing the venturi apparatus of the continuous phase nozzle and the mixed phase nozzle of the venturi apparatus of FIG.

48. . . First entrance

50. . . Venturi device

52. . . suction point

54. . . arrow

56. . . (smaller diameter) channel

58. . . Conical section

60. . . Mixed phase nozzle

62. . . arrow

66. . . Continuous phase nozzle

77. . . Thread

78. . . Sealing ring

80. . . Conical chamber

82. . . Discharge diffuser

84. . . arrow

Claims (14)

A system for emulsifying an oil-in-water or water-in-oil comprising: a venturi device ( 50 ) having a continuous phase nozzle ( 66 ) and a dispersed phase inlet ( 52 ), wherein the continuous phase nozzle has a first diameter ( D1 ), which introduces a continuous phase stream into the mixing section ( 80 ) of the venturi apparatus, and the dispersed phase inlet introduces a dispersed phase into the mixing section to form an emulsion of the dispersed phase and the continuous phase; The tube device includes a mixed phase nozzle ( 60 ) having a second diameter ( d2 ) through which the emulsion is directed from the mixing section to the outlet of the venturi apparatus, the second diameter of the venturi apparatus ( 50 ) ( d2) a ratio greater than 1:1 and less than 4:1 greater than the first diameter ( d1 ), wherein the continuous phase is introduced at a pressure of from about 10 bar to about 50 bar, wherein the continuous phase has from about 10 to 100 m The velocity in the /s range passes through the continuous phase nozzle. The system of claim 1, further comprising pumping the continuous phase to a pump ( 22 ) in the venturi device ( 50 ). The system of claim 1 or 2, wherein the continuous phase comprises an aqueous or starch solution of water or starch. The system of claim 1 or 2, wherein the dispersed phase comprises one or more inverse emulsions. The system of claim 1 or 2, wherein the dispersed phase comprises one or more cellulose non-reactive paper sizing compounds or cellulose reactive paper sizing compounds, such as alkenyl succinic anhydride (ASA), alkyl ketene Polymer (AKD), ketene dimer, ketene polymer, organic epoxide containing from about 12 to 22 carbon atoms, sulfhydryl halide containing from about 12 to 22 carbon atoms, from A fatty acid anhydride of a fatty acid of about 12 to 22 carbon atoms, or an organic isocyanate containing about 12 to 22 carbon atoms. A method of emulsifying a sizing agent for treating paper or paperboard, comprising: introducing a continuous aqueous phase under pressure into a venturi apparatus ( 50 ), the venturi apparatus comprising a first diameter ( d1 ) a continuous phase nozzle ( 66 ) that introduces the continuous phase into the mixing section ( 80 ); introducing a dispersed phase comprising at least one sizing agent into the mixing section ( 80 ) of the venturi apparatus to form the dispersed phase An emulsion of the continuous phase; the emulsion is directed through a mixed phase nozzle ( 60 ) having a second diameter ( d2 ) in the venturi apparatus, the mixed phase nozzle diameter ( d2 ) of the venturi apparatus being A ratio greater than 1:1 and less than 4:1 is greater than the continuous phase nozzle diameter ( d1 ), wherein the continuous phase is introduced at a pressure of from about 10 bars to about 50 bars, wherein the continuous phase has from about 10 to 100 m/s The speed passes through the continuous phase nozzle. The method of claim 6 wherein the continuous phase comprises an aqueous or starch solution of water or starch. The method of claim 6 or 7, wherein the dispersed phase comprises a cellulose non-reactive paper sizing compound or a cellulose reactive paper sizing compound, such as an alkenyl succinic anhydride (ASA), an alkyl ketene dimer ( AKD), ketene dimer, ketene polymer, organic epoxide containing from about 12 to 22 carbon atoms, sulfhydryl halide containing from about 12 to 22 carbon atoms, from about 12 to 22 A fatty acid anhydride of a fatty acid of a carbon atom or an organic isocyanate containing from about 12 to 22 carbon atoms. The method of claim 6 or 7, wherein the dispersed phase further comprises the dispersion One or more surfactants are present in an amount from 0.1% by weight to about 5% by weight. The method of claim 6 or 7, wherein the emulsion has an average particle size of 2 microns or less. The method of claim 6 or 7, wherein the emulsion has a dispersed phase concentration of from 2 to 50% by weight in the continuous phase. The method of claim 6 or 7, further comprising post-emulsion dilution, and adding the post-diluted emulsion to the wet end, or to a size press or coater of a paper or board system. A method of inverting an inverse emulsion comprising introducing a continuous aqueous phase into a venturi apparatus ( 50 ) under pressure, the venturi apparatus comprising a continuous phase nozzle having a first diameter ( d1 ) ( 66) And introducing the continuous phase into the mixing section ( 80 ); introducing a dispersed phase comprising at least one inverse emulsion to the mixing section ( 80 ) of the venturi apparatus to form the dispersed phase and the continuous phase An emulsion; the emulsion is directed through a mixed phase nozzle ( 60 ) having a second diameter ( d2 ) in the venturi apparatus, the mixed phase nozzle diameter ( d2 ) of the venturi apparatus being greater than 1: 1 and less than 4:1 is greater than the continuous phase nozzle diameter ( d1 ), wherein the continuous phase is introduced at a pressure of from about 10 bars to about 40 bars, preferably from about 15 to 25 bars, wherein the continuous phase has about The continuous phase nozzle is passed through at a rate of 10 to 50 m/s, preferably about 25 to 35 m/s. The method of claim 13 wherein the inverse emulsion comprises one or more retention and drainage aids for use in a paper or board system.