JP2013060498A - Powdery ionic water-soluble polymer, and use method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing, at a low cost, a powdery water-soluble polymer whose solution viscosity decreases and whose salt content in the powder is low, because although a polymerization method making an inorganic salt to be present during the polymerization includes a water-in-oil emulsion polymerization method and an in-aqueous salt solution dispersion polymerization method, and a polymer produced exhibits a decreased solution viscosity and a good dispersibility when the polymer produced is dissolved, the in-aqueous salt solution dispersion polymer has a high content of a salt after drying and the water-in-oil emulsion polymerization method costs high.SOLUTION: The powdery ionic water-soluble polymer having a low salt content is produced by using an aqueous solution composed of a specific ionic water-soluble monomer, (meth)acrylamide, and a water-soluble inorganic salt and having a concentration of the monomer in the range of 20 to 80 mass%, and drying, then crushing and finely granulating a polymer or a copolymer produced.

Description

The present invention relates to a powdered ionic water-soluble polymer and a method for using the same, and more specifically, a monomer or monomer mixture aqueous solution concentration of a specific monomer and an inorganic salt is 20 to 80% by mass. A powdered ionic water-soluble polymer characterized in that an aqueous solution in the range is dried after polymerized or copolymerized and then pulverized and further refined, further improving yield and / or drainage The present invention relates to a papermaking method that is added to a papermaking raw material before papermaking, and a sludge dewatering method that is added to sludge and dehydrated after aggregation.

Polymer flocculants include powder products and liquid products, and liquid products include aqueous solution products and dispersed products. Both have advantages and disadvantages, and proper use seems to be an important factor. Powdered products are advantageous to transport, maintain physical properties easily, and maintain stability for a long time. On the other hand, liquid products are contrary to powdered products in terms of transportation and maintenance of physical properties, but do not have a drying process and are advantageous in terms of energy and are easy to dissolve. The most widely used production method for powdered products is a method in which a high-concentration monomer aqueous solution is polymerized, and a gel-like product is granulated, dried, pulverized, and pulverized (Patent Documents 1 and 2). .

Regarding the method of allowing the presence of an inorganic salt during polymerization, a method of water-in-oil emulsion polymerization is disclosed, but there is no description regarding drying (Patent Document 3), and the drying method by this polymerization method is a polymer in a dispersed phase. Since the aqueous solution concentration is 50 to 80% by mass and the dispersion liquid in which the oil and emulsifier of the dispersion medium coexist is dried, the situation is greatly different from the dry method of the polymer of the aqueous solution.
JP 2003-251106 A JP 2004-059719 A JP 2011-099076 A

Polymerization methods in which inorganic salts are present during polymerization include water-in-oil emulsion polymerization methods and dispersion polymerization methods in aqueous salt solutions, but when the produced polymer is dissolved, the viscosity of the solution decreases, and sludge and papermaking raw materials are used. When added, it is known that the dispersibility is good and the dewatering performance of sludge and the formation of the papermaking raw material are improved (Patent Document 3). However, the dispersion polymer in the salt aqueous solution has a mass ratio of the water-soluble polymer and the inorganic salt in the dispersion of 1: 1 or more, and the salt content is too high even when dried and powdered. As a method for drying and pulverizing a polymer of water-soluble polymer, there is a method of spray-drying water-in-oil emulsion polymerization. This method is advantageous when the crosslinkable polymer is dried, but generally a method of high concentration polymerization, granulation, drying, pulverization, etc. is simple in operation and most advantageous in terms of cost. Accordingly, an object of the present invention is to provide a method for producing a powder-type water-soluble polymer with low salt content and efficiently in a method for producing a powder-type water-soluble polymer having a reduced solution viscosity. There is.

As a result of intensive studies to solve the above problems, the present inventors have reached the following invention. That is, the invention of claim 1 includes a water-soluble monomer represented by the following general formula (1) and / or the following general formula (2), a water-soluble monomer represented by the following general formula (3), ( An aqueous solution composed of (meth) acrylamide and a water-soluble inorganic salt, and after drying the polymer or copolymer obtained by polymerizing an aqueous solution having a monomer concentration in the aqueous solution in the range of 20 to 70% by mass, It is a powdered ionic water-soluble polymer characterized by being pulverized and finely divided.
General formula (1)
R1 is hydrogen or a methyl group, R2 and R3 are alkyl groups having 1 to 3 carbon atoms, alkoxy groups, and R4 is hydrogen, an alkyl group having 1 to 3 carbon atoms, an alkoxy group, or a benzyl group, which may be the same or different. A represents oxygen or NH, B represents an alkylene group or alkoxylene group having 2 to 4 carbon atoms, and X1 represents an anion.
General formula (2)
R5 represents hydrogen or a methyl group, R6 and R7 each represents an alkyl group having 1 to 3 carbon atoms, an alkoxy group or a benzyl group, and X2 represents an anion.

General formula (3)
R ₈ is hydrogen, methyl group or carboxymethyl group, R ₉ is hydrogen or carboxyl group, Q is SO ₃ , C ₆ H ₄ SO ₃ , CONHC (CH ₃ ) ₂ CH ₂ SO ₃ or COO, M is hydrogen or positive Each represents an ion.

In the invention of claim 2, the copolymerization ratio of the water-soluble monomer represented by the general formula (1) and / or the following general formula (2) is 5 to 40 mol%, and represented by the general formula (3). The powdered ionicity according to claim 1, wherein the copolymerization ratio of the water-soluble monomer is 0 to 10 mol%, and the copolymerization ratio of (meth) acrylamide is 50 to 95 mol%. It is a water-soluble polymer.

The invention according to claim 3 is the powdered ionic water-soluble polymer according to claim 1, wherein the concentration of the inorganic salt in the aqueous solution is 3 to 15% by mass.

The invention of claim 4 is characterized in that the water-soluble inorganic salt is a combination of one selected from sodium, potassium and ammonium ions as a cation and one combination selected from a halide ion, sulfate ion and phosphate ion as an anion. The powdered ionic water-soluble polymer according to claim 1, wherein

The invention of claim 5 adds the aqueous solution of the powdered ionic water-soluble polymer according to claims 1 to 4 to a papermaking raw material before papermaking for the purpose of improving yield and / or drainage. This is a paper manufacturing method characterized by the above.

The invention according to claim 6 is an aqueous suspension characterized in that the aqueous solution of the powdered ionic water-soluble polymer according to any one of claims 1 to 4 is added to an aqueous suspension and agglomerated and then solid-liquid separated. It is a processing method.

The existing water-in-oil emulsion polymerized product in the presence of salt is mixed with a surfactant and oil as a dispersion medium after pulverization, and the powdered product of the dispersion polymerized product in salt aqueous solution has a salt concentration of 40% of the total. Also contains ~ 50% by weight. In contrast, a powder product produced by polymerizing a high-concentration solution of the monomer of the present invention and granulating, drying, pulverizing, etc. has a low salt concentration and a low additive concentration, and the stability is the current powder. It is the same as the product. And the performance is high in dispersibility in the aqueous dispersion targeted for water treatment due to its low apparent aqueous solution viscosity, resulting in a reduction in the amount added, and when applied to sludge dewatering agents, A decline can also be expected. In addition, when applied to papermaking chemicals, the texture of the paper is improved due to its high dispersibility, and when added to the papermaking raw material, it can be expected that the chemical concentration will be set high, leading to saving of dilution water.

The powdered ionic water-soluble polymer of the present invention has a water-soluble monomer or monomer mixture aqueous solution concentration of 20 to 20 consisting of a cationic water-soluble monomer, 0 to 95 mol% of (meth) acrylamide, and a water-soluble inorganic salt. An aqueous solution in the range of 80% by mass can be produced by drying a polymerized or copolymerized product and then pulverizing and granulating it. The polymerization is initiated by irradiation with a radical polymerization initiator or photosensitizer and ultraviolet light, visible light, electron beam or the like. The polymer form is polymerized into a thin form such as a sheet or a thick form such as a rectangular parallelepiped, then crushed, granulated with a meat chopper, etc., dried, pulverized dry matter, sieving, etc. After that, a powdered ionic water-soluble polymer product can be obtained.

By granulating the polymer in a gel state before drying, the drying can be performed more efficiently than in the case of a coarse lump. If the average particle size of the granulated product before drying is less than 0.5 mm, the load on the granulating device increases during granulation, which is not efficient. When the particle diameter of the granulated product exceeds 20 mm, it becomes difficult to dry the inside sufficiently during drying. The average particle size of the granulated product before drying is preferably 0.5 mm to 20 mm, more preferably 1.0 mm to 10 mm.

There is no restriction | limiting in particular in the drying method after granulation, Methods, such as hot air drying, conductive heat transfer drying, and radiant heat drying, can be used. In particular, hot air drying with good drying efficiency such as fluidized drying and aeration drying is preferable. By treating the solid material dried after drying with various pulverizers, fine particles having an average particle diameter of the order of micrometers can be obtained in addition to relatively large particles.

The concentration of the monomer or monomer mixture aqueous solution is in the range of 20 to 80% by mass. However, if the concentration is high, the drying process is quick, but the degree of polymerization of the water-soluble polymer may not be increased. In some cases, the concentration is too high to allow coarse crushing and granulation. Therefore, it is generally 20 to 80% by mass, but preferably 25 to 60% by mass.

The starting temperature is preferably 10 to 40 ° C. when a radical polymerization initiator is used, but can be started even at 0 ° C. when it is started by irradiation with a photosensitizer and ultraviolet light, visible light, or an electron beam. Although it exists, Preferably it is 10-40 degreeC. In general, in the case of a monomer composition having a high content such as acrylamide, it starts at a low temperature such as 10 to 30 ° C., and in the case of a monomer composition having a high content such as acryloyloxyethyltrimethylammonium chloride, 25 to 40 or the like. Polymerization starts at a high temperature range.

As the polymerization initiator, an azo initiator, a redox initiator, or the like can be used as a radical polymerization initiator. Moreover, when performing photopolymerization, a photoinitiator is used.

The radical polymerization initiator can be either oil-soluble or water-soluble, but can be polymerized by any of azo, peroxide, and redox systems. Examples of oil-soluble azo initiators are 2,2′-azobisisobutyronitrile, 1,1-azobiscyclohexanecarbonitrile, 2,2′-azobis-2-methylbutyronitrile, 2,2 Examples include '-azobis-2-methylpropionate, 4,4'-azobis- (4-methoxy-2,4-dimethyl) valeronitrile.

Examples of water soluble azo initiators are 2,2'-azobis (amidinopropane) dichloride, 2,2'-azobis [2- (5-methyl-imidazolin-2-yl) propane] hydrogen dichloride And 4,4′-azobis (4-cyanovaleric acid). Examples of redox systems include a combination of ammonium peroxodisulfate and sodium sulfite, sodium hydrogen sulfite, trimethylamine, tetramethylethylenediamine and the like. Examples of peroxides include ammonium or potassium peroxodisulfate, hydrogen peroxide, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, succinic peroxide, t-butylperoxy-2-ethylhexanoate, etc. Can be mentioned.

A photoinitiator will not be specifically limited if it is a compound which produces a radical by irradiation of light and can start superposition | polymerization of a water-soluble monomer. α-hydroxy ketones, acylphosphine oxide compounds and the like can be used, and examples thereof include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- ( 2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethyl Examples thereof include tilbenzoyldiphenylphosphine oxide, benzoin, benzoin ethyl ether, and benzophenone. In the present invention, since a water-soluble monomer is mainly used, it is preferably dissolved in water and added to the monomer solution. However, when insoluble in water, an organic solvent such as a water-miscible alcohol is preferable. An organic solvent such as toluene that is immiscible with water can also be used.

The azo polymerization initiator can be used as the photopolymerization initiator. When carrying out photopolymerization, it is preferable to use the above radical polymerization initiator in combination, since the polymerization proceeds smoothly. The radical polymerization initiator is preferably a redox initiator or an azo initiator. Examples of redox initiators include, but are not limited to, sodium persulfate and sodium sulfite, or a combination of ammonium persulfate (APS) and N, N, N ′, N′-tetramethylethylenediamine (TEMED). It is not a thing.

When performing photopolymerization, it is preferable to irradiate ultraviolet light, particularly near ultraviolet light. The generation of near ultraviolet rays includes high pressure mercury lamps, low pressure mercury lamps, metal halide lamps, fluorescent chemical lamps, fluorescent blue lamps and the like. Further, the wavelength region of near ultraviolet rays is 300 nm or more, and preferably 500 nm or less.

The irradiation intensity of the ultraviolet rays is preferably 0.1 to 100 W / m ² . In particular, it is preferable to initiate polymerization by irradiating near ultraviolet rays with an intensity of 10 W / m ² or less. Further, it is preferably 8 W / m ² or less, and more preferably 6 W / m ² or less. Further, during the polymerization by irradiation with near ultraviolet rays, the irradiation intensity of near ultraviolet rays may be constant or may be changed, but the polymerization is performed by adjusting the maximum irradiation intensity to 10 W / m ² or less. Is preferably initiated.

The cationic monomers used in the present invention include the following. That is, it is a quaternized product of methyl chloride or benzyl chloride such as dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, and methyldiallylamine. Examples of the monomer represented by the general formula (1) include (meth) acryloyloxyethyltrimethylammonium chloride, (meth) acryloyloxy-2-hydroxypropyltrimethylammonium chloride, (meth) acryloylaminopropyltrimethylammonium. Chloride, (meth) acryloyloxyethyldimethylbenzylammonium chloride, (meth) acryloyloxy-2-hydroxypropyldimethylbenzylammonium chloride, (meth) acryloylaminopropyldimethylbenzylammonium chloride. Examples of the monomer represented by the general formula (2) include diallyldimethylammonium chloride.

In the case of producing an amphoteric water-soluble polymer, a vinyl anionic monomer is used in combination with the vinyl cationic monomer. Examples thereof include vinyl sulfonic acid, vinyl benzene sulfonic acid or 2-acrylamido-2-methylpropane sulfonic acid represented by the general formula (3), methacrylic acid, acrylic acid, itaconic acid, maleic acid, phthalic acid or p. -Carboxystyrene acid etc. are mention | raise | lifted.

When copolymerizing nonionic monomers, (meth) acrylamide, N, N-dimethylacrylamide, acrylonitrile, 2-hydroxyethyl (meth) acrylate, diacetone acrylamide, N-vinylpyrrolidone, N- Vinylformamide, N-vinylacetamide, acryloylmorpholine and the like can be mentioned.

The copolymerization ratio of these monomers is as follows. The cationic monomer is 5 to 100 mol%, the anionic monomer is 0 to 30 mol%, and the nonionic monomer is 0 to 95 mol%. In the present invention, when used as a dewatering agent for sludge, it is necessary that the cationicity is high to some extent, and therefore preferably 20 to 100 mol% of a cationic monomer, 0 to 20 mol% of an anionic monomer, and nonionic 0 to 80 mol% of the ionic monomer is preferable, more preferably 40 to 100 mol% of the cationic monomer, 0 to 20 mol% of the anionic monomer, and 0 to 60 mol% of the nonionic monomer. . When used as a papermaking yield, 5-40 mol% of cationic monomers, 0-10 mol% of anionic monomers, 60-90 mol% of nonionic monomers are preferred, and more preferred. Is 5 to 30 mol% of a cationic monomer, 0 to 10 mol% of an anionic monomer, and 70 to 95 mol% of a nonionic monomer.

The inorganic salt that is allowed to coexist in the monomer aqueous solution during polymerization is preferably one having high solubility in the monomer aqueous solution, but is as follows. That is, a salt in which a cation such as alkali metal ion or ammonium ion such as sodium or potassium and an anion such as halide ion, sulfate ion, nitrate ion or orthophosphate ion can be used. The concentration of these salts is 3 to 15% by mass, preferably 5% to 15% by mass, based on the entire aqueous solution. Further, as specific salts, ammonium sulfate, sodium chloride, sodium sulfate, magnesium sulfate and the like are preferable, and ammonium sulfate is particularly preferable.

The apparent viscosity of the aqueous solution of the ionic water-soluble polymer polymerized in the presence of the inorganic salt of the present invention is lowered. For example, in a polymer composed of 20 mol% of acryloyloxyethyltrimethylammonium chloride and 80 mol% of acrylamide, a 0.2 mass% solution is 149 mP · s (B type viscometer, 25 ° C.). It can be recognized from the fact that in a commercially available powder product whose composition is polymerized and powdered in the absence of a normal inorganic salt, a 0.2 mass% solution of the polymer is 526 mP · s.

According to the present invention, a polymer produced by high-concentration aqueous solution polymerization of 20 to 80% by mass in the presence of an inorganic salt is a polymer obtained by polymerizing an ionic water-soluble polymer in the absence of a salt and an aqueous salt solution. It can be considered as a polymer intermediate between polymerization by salting-out polymerization such as dispersion polymerization. The polymer obtained by salting-out polymerization is completely salted out and insolubilized.
It is considered that the polymer polymerized in an aqueous solution in the presence of salt differs in the contraction state of the polymer chain depending on the coexisting salt concentration. When the monomer concentration is 20% by mass, the remainder is 80% by mass, but when the inorganic salt concentration is 10% by mass, the water is 70% by mass, and the mass ratio of monomer, inorganic salt, and water is 1: 0. .5: 3.5, and both the monomer: inorganic salt and the monomer: water have a considerably high concentration. When the monomer concentration is 40% by mass, the balance is 60% by mass, but when the inorganic salt concentration is 10% by mass, the water is 50% by mass, and the mass ratio of monomer, inorganic salt, and water is 1: 0.25: 0.8. A relatively large amount of salt is present in a relatively small amount of water, resulting in a specific physical and chemical state. Therefore, it may be crystallized or physically cross-linked. Therefore, it is considered that the polymer chain is in a compact state and the dispersibility is improved accordingly.

The molecular weight of the ionic water-soluble polymer obtained by polymerizing the monomer according to the present invention is 3 million to 30 million as a weight average molecular weight by light scattering, and can be adjusted according to the purpose of use. For example, when used as a sludge dehydrating agent, it is 3 million to 10 million, preferably 5 million to 8 million. If it is lower than 3 million, agglomeration is insufficient and the dehydrator may not be applied, which is not recommended. On the other hand, if it is higher than 10 million, huge flocs are produced, and the moisture content of the cake after dehydration may not be returned to decrease. When used as a papermaking yield, it is 5 million to 30 million, preferably 7 million to 30 million. If it is lower than 5 million, the yield rate is not improved and is not practical, and if it is higher than 30 million, the cohesive force is too strong and the formation of the formed paper is disturbed.

(Example)
The sludge dehydrating agent comprising the water-in-oil emulsion of the cationic or amphoteric polymer of the present invention will be specifically described by the following examples, but the present invention is not limited to the following examples.

Example 1
A 500 mL polyvinyl beaker was charged with 201.0 g of an 80% by weight aqueous solution of acryloyloxyethyltrimethylammonium chloride, 78.4 g of a 50% by weight acrylamide solution, and 12.0 g of ammonium sulfate, and the pH was adjusted to 3.5 with a 20% by weight aqueous sulfuric acid solution. The whole solution was adjusted to 398 g. At this time, the molar ratio of acryloyloxyethyltrimethylammonium chloride and acrylamide copolymer is 60:40, and the concentration of ammonium sulfate in the solution is 3.0% by mass. Thereafter, the liquid temperature was kept at 35 ° C. in a nitrogen atmosphere, and 1.2 g of a 2,2′-azobis [2- (5-methyl-imidazolin-2-yl) propane] dihydrochloride 5% by mass aqueous solution as a polymerization initiator. (300 ppm monomer) was added, the whole was stirred and made uniform, and poured into a stainless steel container having a depth of 3 cm and a diameter of 20 cm. The solution thickness at this time is about 1.3 cm. Nitrogen was kept flowing for 2 hours after the start of polymerization. After superposition | polymerization, it pick_out | removed from the stainless steel container, the superposition | polymerization gel-like thing was granulated to 1-3 mm with the meat chopper, and it dried at 100 degreeC with the ventilation dryer for 10 hours. After drying, it was pulverized to obtain a powdery water-soluble polymer having an average particle size of 1.5 mm. The powdery water-soluble polymer was redissolved and the viscosity in 0.5% by mass of 1N saline was measured with a B-type viscometer (25 ° C.), and further 0.2, 0 at 25 ° C. in 1N saline. 0.1, 0.05 g / dl of each concentration solution was prepared, the reduced viscosity was measured with an Ostwald viscometer, and extrapolated to a concentration of 0 to obtain the intrinsic viscosity (IV). This sample was designated as Sample-1 and the results are shown in Tables 1 and 2.

Prototype-2 to prototype-14 were synthesized in the same manner as in Example 1, and the viscosity was measured. The results are shown in Tables 1 and 2.

(Example 2)
In a 500 mL polyvinyl beaker, 201.0 g of an 80% by weight aqueous solution of acryloyloxyethyltrimethylammonium chloride, 78.4 g of a 50% by weight acrylamide solution, 28.0 g of ammonium sulfate, and 1.0 g of a 10% sodium riboflavin sodium phosphate solution (compared with 0.1% monomer). 05% by mass), the pH was adjusted to 3.5 with a 20% by mass sulfuric acid aqueous solution, and the whole solution was adjusted to 398 g. At this time, the molar ratio of acryloyloxyethyltrimethylammonium chloride and acrylamide copolymer is 60:40, and the concentration of ammonium sulfate in the solution is 9.0% by mass. Thereafter, the liquid temperature was kept at 20 ° C. under a nitrogen atmosphere, and a 2,2′-azobis [2- (5-methyl-imidazolin-2-yl) propane] dihydrochloride 5 mass% aqueous solution as a photopolymerization initiator. 2 g (with respect to monomer 300 ppm) was added, the whole was stirred and made uniform, and poured into a stainless steel container having a depth of 3 cm and a diameter of 20 cm. The solution thickness at this time is about 1.3 cm. Thereafter, UV (light quantity of 365 nm, 20 mW / cm ² ) was irradiated with a 400 W high-pressure mercury lamp to initiate polymerization. UV irradiation and nitrogen inflow were continued for 2 hours. After superposition | polymerization, it took out from the stainless steel container, the superposition | polymerization gel-like thing was granulated to 1-3 mm with the meat chopper, and it dried at 100 degreeC with the ventilation dryer for 15 hours. After drying, it was pulverized to obtain a powdery water-soluble polymer having an average particle size of 1.5 mm. The powdery water-soluble polymer was redissolved, and the viscosity in 0.5% by mass and 1N saline was measured with a B-type viscometer (25 ° C.),
Furthermore, after preparing solutions with various concentrations of 0.2, 0.1 and 0.05 g / dl at 25 ° C. in 1N saline solution, measuring the reduced viscosity with an Ostwald viscometer, extrapolating to a concentration of 0 Thus, the intrinsic viscosity (IV) was determined.
This sample is designated as Sample-15. Sample-16 was prepared in the same manner. These results are shown in Tables 1 and 2.

(Table 1)
DMC: methacryloyloxyethyltrimethylammonium chloride, DMQ: acryloyloxyethyltrimethylammonium chloride, AAM: acrylamide, AAC; acrylic acid,
Inorganic salt type (mass%); inorganic salt concentration with respect to the whole solution,
a: ammonium sulfate, b: salt, c: sodium sulfate, d: magnesium sulfate,

(Table 2)
Powder average particle size; mm, 0.2% aqueous solution viscosity; mPa · s,
Intrinsic viscosity; dL / g

(Example 3)
Samples 31-32, Comparative-24, and Comparative-24 with ammonium sulfate added to 7.0% by mass of water-soluble polymer (same as mass% of monomer before polymerization) (comparative) With respect to -27), a dispersibility test in papermaking raw materials was performed. The raw material used was a solid paper making raw material having a solid content concentration of 1.2% by mass and a light calcium calcium carbonate or other Ash content containing 32.0% solid content concentration. The physical properties of the papermaking raw material are pH 7.5, Whatman No. The required cation amount of 41 filter paper filtrate using the Mutec PCD-03 type is 0.005 meq / L. For the dispersibility test, “Flockkey Tester” manufactured by Koei Kogyo Co., Ltd. was used. When a water-soluble polymer is added to a papermaking raw material, the papermaking raw material is agglomerated and resistance is applied to the stirrer. When the voltage is high, the aggregation is in a high state, and when the voltage is quickly increased from the time of addition, the aggregation occurs early and the water-soluble polymer is dispersed quickly. In the test, stirring of “Flockey Tester” is started after 0 seconds shown in Table 3, and a water-soluble polymer is added after 10 seconds, and the aggregation state over time is automatically recorded by a personal computer. The results are shown in Table 3.

(Table 3)
Stirring time; seconds,

Sample-31 and Sample-32 are water-soluble polymers added with salt and polymerized, and show a good aggregation state 20 seconds after the addition, indicating that the dispersibility is good. On the other hand, Comparative -24 shows little aggregation even after 20 seconds after addition, and shows the maximum aggregation state 30 seconds after addition, but the maximum value is lower than that of Sample-31 and Sample-32. This means that the cohesiveness itself is low. Comparative-27 is a solution obtained by adding a salt of the same ratio as Sample-31 and Sample-32 to a water-soluble polymer solution, but the aggregation after 20 seconds from the addition is improved. Is similar, and it can be seen that the agglomeration performance is low as compared with Sample-31 to which salt was added during polymerization.

Example 4
Yield rate measurement test was performed with a Brit dynamic jar tester. Use 200 mesh wire. The raw material used was a solid paper making raw material having a solid content concentration of 1.2% by mass and a light calcium calcium carbonate or other Ash content containing 32.0% solid content concentration. The physical properties of the papermaking raw material are pH 7.5, Whatman No. The required cation amount of 41 filter paper filtrate using the Mutec PCD-03 type is 0.005 meq / L. After stirring for 20 seconds at a stirring speed of 1200 rpm, Sample-22 and Sample-31 to Sample-33 were added at 150 ppm with respect to the solid content of the paper, and stirred for 10 seconds at a stirring speed of 1200 rpm, and the filtrate was collected and ADVANTEC, No. . After filtration with two filter papers, SS was measured, and the total yield was measured. Then, the filter paper was ashed at 525 ° C. for 2 hours, and the ash yield was measured. The results are shown in Table 4.

Next, paper with a basis weight of 90 g / m ² was made using a TAPPI standard paper machine (using 60 mesh wire). The pH at the time of papermaking was 7.0. The wet paper we made is press dehydrated with a press at 4.1 kgf / cm ² for 5 minutes, dried with a rotary drum dryer at 105 ° C. for 3 minutes, and then conditioned for 18 hours at 25 ° C. and 65% humidity. The specific burst strength and the formation index were measured in accordance with JIS P8131. The texture index is M / K System Inc. It was measured by “3D Sheet Analyzer” manufactured by the company. The higher this number, the better the texture.

(Comparative Example 1)
Using the same papermaking raw material as in Example 4, 150 ppm of Comparative-24 to Comparative-26 was added to the solid content of the paper stock, and stirred for 20 seconds at 1200 rpm, followed by Sample-22 and Sample-31-31. Sample 33 was added at 150 ppm with respect to the solid content of the paper and stirred at a rotation speed of 1200 rpm for 10 seconds, and then the filtrate was collected to obtain ADVANTEC, After filtration with two filter papers, SS was measured, and the total yield was measured. Then, the filter paper was ashed at 525 ° C. for 2 hours, and the ash yield was measured. In the same manner as in Example 4, the formation after papermaking was also measured.
The results are shown in Table 4.

Each sample of the examples improves the total yield rate and the calcium carbonate yield rate, and exhibits a good effect. In addition, the formation has a good value of around 80%. In contrast, each of the comparative samples has a lower total yield rate and a calcium carbonate yield rate than the respective samples of the examples, and the formation is also low. This is because each comparative sample has a lower dispersibility in the papermaking raw material than each sample in the examples, the agglomeration action is delayed, uniform floc formation can be sent, the yield rate is lowered, and the formation is also lowered. .

(Table 4)

(Example 5)
A coagulation filtration test and a squeezing test were performed on sewage mixed raw sludge generated from a sewage treatment plant (sludge property is pH 6.4, SS: 35,000 mg / L). After 200 mL of sludge was put into a 300 mL polypropylene beaker, after dry powderization, Sample-21 to Sample-27, Sample-30 and Sample-33 to Sample-35 were added to each SS content 0.70% by mass, Sludge was agglomerated by stirring at 1000 rpm for 30 seconds. Then, after observing the size of the floc, the filtration rate was examined with a 40 mesh beaker with a filter cloth. Further, the water content of the dehydrated cake was determined after press dewatering the aggregate after filtration for 30 seconds at a pressing pressure of 1 kgf / cm ² . The results are shown in Table 5.

(Comparative Example 2)
The same sludge as Example 5 was used, and the same operation was performed regarding Comparative-21 to Comparative-23 after dry powderization. The results are shown in Table 5.

(Table 5)
10 seconds later, filtrate amount; mL, cake moisture content; mass%, floc diameter; mm

Each sample of the examples shows a sufficient agglomeration effect, and the moisture content of the cake is also reduced and a good effect is exhibited. On the other hand, in each comparative sample, the agglomeration effect is lowered and the moisture content of the cake is not lowered. It is considered that this indicates that each of the comparative samples has a lower dispersibility of the drug in the sludge than each sample of the example, and the coagulation action is delayed.

Claims (6)

Water-soluble monomer represented by the following general formula (1) and / or the following general formula (2), water-soluble monomer represented by the following general formula (3), (meth) acrylamide, and water-soluble inorganic An aqueous solution comprising a salt, the monomer concentration in the aqueous solution being in the range of 20 to 70% by mass, after drying the polymerized product or copolymer, pulverized and finely divided A characteristic powdered ionic water-soluble polymer.
General formula (1)
R1 is hydrogen or a methyl group, R2 and R3 are alkyl groups having 1 to 3 carbon atoms, alkoxy groups, and R4 is hydrogen, an alkyl group having 1 to 3 carbon atoms, an alkoxy group, or a benzyl group, which may be the same or different. A represents oxygen or NH, B represents an alkylene group or alkoxylene group having 2 to 4 carbon atoms, and X1 represents an anion.
General formula (2)
R5 represents hydrogen or a methyl group, R6 and R7 each represents an alkyl group having 1 to 3 carbon atoms, an alkoxy group or a benzyl group, and X2 represents an anion.

General formula (3)
R ₈ is hydrogen, methyl group or carboxymethyl group, R ₉ is hydrogen or carboxyl group, Q is SO ₃ , C ₆ H ₄ SO ₃ , CONHC (CH ₃ ) ₂ CH ₂ SO ₃ or COO, M is hydrogen or positive Each represents an ion. The copolymerization ratio of the water-soluble monomer represented by the general formula (1) and / or the general formula (2) is 5 to 40 mol%, and the water-soluble monomer represented by the general formula (3) The powdered ionic water-soluble polymer according to claim 1, wherein the copolymerization ratio is 0 to 10 mol%, and the copolymerization ratio of (meth) acrylamide is 50 to 95 mol%. The powdered ionic water-soluble polymer according to claim 1 or 2, wherein the concentration of the inorganic salt in the aqueous solution is 3 to 15% by mass. The water-soluble inorganic salt is one selected from sodium ion, potassium ion, calcium ion, magnesium ion, barium ion, ammonium ion as cation, and chloride ion, bromide ion, iodide ion, sulfate ion as anion. The powdered ionic water-soluble polymer according to claim 1, which is a kind of combination selected from phosphate ions. A papermaking method comprising adding the aqueous solution of the powdered ionic water-soluble polymer according to claims 1 to 4 to a papermaking raw material before papermaking for the purpose of improving yield and / or drainage. . A method for treating an aqueous suspension, comprising adding the aqueous solution of the powdered ionic water-soluble polymer according to claims 1 to 4 to the aqueous suspension and aggregating the mixture, followed by solid-liquid separation.