JP2015217343A - Coagulation treatment agent, and dewatering method of sludge using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a coagulation treatment agent enabling a highly-efficient dewatering treatment to organic sludge generated by treatment of sewage, excrement and industrial waste water; and to provide a dewatering method using the same.SOLUTION: There is provided a coagulation treatment agent comprising water-in-oil type emulsion of a cationic or amphoteric water-soluble polymer obtained by performing emulsion polymerization so as to acquire a dispersion phase from specific monomer mixture aqueous solution and a continuous phase from organic liquid by a surfactant concerning the organic liquid non-miscible with water. A highly-efficient dewatering treatment can be attained by adding the coagulation treatment agent into organic sludge.

Description

The present invention relates to an aggregating agent or a method for dewatering sludge using an aggregating agent, and more specifically, a cationic or amphoteric aqueous polymer produced by emulsion polymerization of a monomer mixture having a specific structural unit. The present invention relates to a coagulation treatment agent comprising a water-in-oil emulsion, and a sludge dewatering method in which the coagulation treatment agent is added to organic sludge.

Polyacrylamide (PAM) system high for organic sludge such as primary sludge settled from sewage, surplus sludge settled from effluent from activated sludge tank or mixed raw sludge in municipal wastewater treatment plants A sludge dewatering method in which a molecular flocculant is added and dewatered is widely used, and various flocculants having a specific structure and composition have been proposed. Among them, there is a case in which a dehydration effect is improved by neutralizing with suspended particles in sludge by using a PAM polymer flocculant having a high degree of cationization. For example, Patent Document 1 discloses a method of adding a water-in-oil type polymer emulsion comprising a highly cationic and highly crosslinkable aqueous polymer having a specific structural unit to sludge. In Patent Document 2, a cationic polymer having a benzyl chloride quaternary salt of dialkylaminoethyl methacrylate as a cationic constituent unit of 50 mol% or more, a cationic constituent unit of 20 to 30 mol%, and an anionic constituent unit of 30 to 45 mol%. And an amphoteric polymer having 25 to 50 mol% of nonionic structural units and 0.5 to 1 mol times of cationic structural units of anionic structural units is disclosed. . However, when dealing with recent dewatered sludge with these high cationized polymer flocculants, it is necessary to increase the molecular weight. If the molecular weight is increased, the aggregate flocs become larger and moisture is incorporated into the flocs. The phenomenon that the dehydration effect is reduced has occurred, and further improvement of the dehydration effect is desired.

JP 2012-170943 A Japanese Patent Laid-Open No. 2004-121997

An object of the present invention is to develop a coagulation treatment agent that enables efficient dewatering treatment to organic sludge generated in the treatment of sewage, human waste, and industrial wastewater, and a sludge dewatering method that adds the coagulation treatment agent. That is.

In order to solve the above-mentioned problems, the present inventors have intensively studied and as a result, have reached the invention described below. Namely, a flocculating agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer produced by emulsion polymerization of a monomer mixture having a specific structural unit, and sludge in which the flocculating agent is added to organic sludge This is a dehydration method.

The coagulation treatment agent in the present invention can achieve a dehydration effect superior to the addition of a conventional coagulation treatment agent to organic sludge.

The aggregating agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer in the present invention has a specific cationic group and a molar composition introduced therein, and has a specific cationic group and a molar composition or physical properties. By having it, it has excellent dehydration performance.

The aggregating treatment agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer in the present invention is a cationic monomer represented by the following general formula (1) and / or (2): 70 to 90 mol% 10 to 20 mol% of a cationic monomer represented by the following general formula (3), 0 to 20 mol% of an anionic monomer represented by the following general formula (4), 0 nonionic monomer ~ 20 mol%, and a monomer mixture aqueous solution containing 0-50 ppm by mass of the crosslinkable monomer with respect to the monomer mixture as a dispersed phase, and a water-immiscible organic liquid as a surfactant Is obtained by emulsion polymerization of an organic liquid into a continuous phase.
General formula (1)
R ₁ is hydrogen or a methyl group, R ₂ and R ₃ are alkyl or hydroxyalkyl groups having 1 to 3 carbon atoms, R ₄ is hydrogen and an alkyl group having 1 to 3 carbon atoms, which may be the same or different, and A is oxygen or NH, B represents an alkylene group having 2 to 4 carbon atoms, _{X 1} ^- represents respectively an anion.

General formula (2)
R ₅ represents hydrogen or a methyl group, R ₆ and R ₇ represent an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group, and X ₂ ⁻ represents an anion.

General formula (3)
R ₈ is hydrogen or a methyl group, R ₉ and R ₁₀ are alkyl or hydroxyalkyl groups having 1 to 3 carbon atoms, R ₁₁ is an alkyl group or aryl group having 7 to 20 carbon atoms, A is oxygen or NH, B Represents an alkylene group having 2 to 4 carbon atoms, and X ₃ ⁻ represents an anion.

General formula (4)
R ₁₂ is hydrogen, methyl group or carboxymethyl group, Q is SO ₃ , C ₆ H ₄ SO ₃ , CONHC (CH ₃ ) ₂ CH ₂ SO ₃ , C ₆ H ₄ COO or COO, R ₁₃ is hydrogen or COOY ₂ , Y ₁ or Y ₂ represents hydrogen or a cation, respectively.

As the cationic monomer represented by the general formula (1) and / or the general formula (2) during the production of the aggregation treatment agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer in the present invention, Examples include dimethylaminoethyl (meth) acrylate and the like, tertiary salts such as diallylalkylamine, and alkyl halides such as methyl chloride. These cationic vinyl monomers can be used alone, Two or more kinds may be used in combination. As a specific example, the cationic monomer represented by the general formula (1) is quaternary by dimethylaminoethyl (meth) acrylate or dimethylaminopropylacrylamide, such as methyl chloride or ethyl chloride, which is a lower alkyl group halide. It is a monster. For example, (meth) acryloyloxyethyltrimethylammonium chloride, (meth) acryloyloxy-2-hydroxypropyltrimethylammonium chloride, (meth) acryloylaminopropyltrimethylammonium chloride, and the like. Examples of the cationic monomer represented by the general formula (2) include diallylmethylammonium chloride and diallyldimethylammonium chloride.

The cationic monomer represented by the general formula (3) is a halogenated aryl compound such as benzyl chloride of dimethylaminoethyl (meth) acrylate or dimethylaminopropyl acrylamide, or an alkyl halide having 7 to 20 carbon atoms. These cationic vinyl monomers can be used alone or in combination of two or more. Specific examples include (meth) acryloyloxyethyldimethylbenzylammonium chloride, (meth) acryloyloxy-2-hydroxypropylbenzyldimethylammonium chloride, (meth) acryloylaminopropyldimethylbenzylammonium chloride, and the like.

In the present invention, a good dehydration effect may be achieved even when an amphoteric water-soluble polymer is used, and the amphoteric water-soluble polymer is produced using an anionic monomer represented by the general formula (4). Examples of the anionic monomer represented by the general formula (4) include alkali metal salts or ammonium salts such as (meth) acrylic acid or a sodium salt thereof, maleic acid or an alkali metal salt thereof, and acrylamido-2-methylpropanesulfone. Examples thereof include acrylamide alkanesulfonic acids such as acids, alkali metal salts or ammonium salts thereof. As a mole number of an anionic monomer, it is the range of 0-20 mol%.

The aggregating treatment agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer in the present invention is produced using a cationic monomer represented by the general formula (3). ) Is a (meth) acrylic water-soluble polymer having a hydrophobic side chain such as a benzyl group. This cationic monomer has a range of 10 to 20 mol%, and an acrylic monomer having a cationic monomer represented by the general formula (1) and / or the general formula (2) of 70 to 90 mol%. The present inventors have found that the dewatering performance of the water-soluble polymer is excellent. The neutralization action of sludge suspended particles by the cationic group of 70 to 90 mol% of the cationic monomer represented by the general formula (1) and / or the general formula (2), and the general formula (3) It is considered that the dehydrating property is improved in each stage as compared with the conventional acrylic polymer flocculant by a synergistic effect with the hydrophobic action of 10 to 20 mol% of the cationic monomer.

Nonionic monomers copolymerized as necessary include (meth) acrylamide, N, N-dimethylacrylamide, acrylonitrile, (meth) acrylic acid-2-hydroxyethyl, diacetone acrylamide, N- Vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, acryloylmorpholine and the like can be mentioned.

In order to produce an aggregating agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer in the present invention, a structural modifier, that is, a crosslinkable monomer that structurally modifies the polymer is used during polymerization. You may do it. This is a very effective method in the case of so-called hardly dewatering sludge having a low fiber content. In the present invention, the aggregation treatment agent comprising a water-in-oil emulsion polymerized by containing a crosslinkable monomer, that is, a crosslinkable water-soluble polymer, suppresses the spread of molecules in water compared to a linear polymer. The Therefore, it exists as a more “dense” molecular form. When the cross-linked polymer is added to the sludge, it adsorbs to the suspended particles and acts as an adhesive between the particles, resulting in aggregation of the particles. At this time, it is presumed that since the molecular form is “packed with density”, it is combined with the suspended particle surface at multiple points and does not form a huge floc, but forms a floc with higher tightness and strength. Moreover, flocs with high strength are formed, and an improvement in sludge dewaterability is exhibited. When a crosslinkable monomer is used, the cationic monomer represented by the general formula (1) and / or (2) used when producing the water-in-oil emulsion in the present invention, the general 1 to 50 ppm by mass based on the total amount of the cationic monomer represented by the formula (3), the anionic monomer represented by the general formula (4), and the nonionic monomer. Preferably it is 3 to 50 ppm, more preferably 5 to 50 ppm. If it exceeds 50 ppm, the degree of progress of crosslinking is large, and the amount added is not preferred when used as a flocculant. Examples of the crosslinkable monomer include N, N-methylenebis (meth) acrylamide, triallylamine, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and dimethacrylic acid. Acid-1,3-butylene glycol, polyethylene glycol di (meth) acrylate, N-vinyl (meth) acrylamide, N-methylallylacrylamide, glycidyl acrylate, polyethylene glycol diglycidyl ether, acrolein, glyoxal, vinyltrimethoxysilane In this case, the crosslinking agent is more preferably a water-soluble polyvinyl compound, and most preferably N, N-methylenebis (meth) acrylamide. Further, it may be effective to use 0.1 to 5% by mass of isopropyl alcohol as a chain transfer agent in order to adjust the degree of polymerization.

The degree of cross-linking of the cross-linkable water-soluble polymer varies depending not only on the addition rate of the cross-linkable monomer at the time of production but also on the polymerization conditions and composition. Alternatively, the amphoteric water-soluble polymer is a ratio of the viscosity of the aqueous solution having a polymer concentration of 0.2% by weight to the viscosity in a 4% by weight saline solution having a polymer concentration of 0.5% by weight (0.2% by weight aqueous solution viscosity / 0.5 (Mass% viscosity in 4% by weight saline solution) can be used as an indicator of the degree of crosslinking. For example, when the viscosity of a 0.2 mass% aqueous solution is 260 mPa · s and the viscosity of a 0.5 mass% 4 mass% saline solution is 17 mPa · s, this value is 15.2. Cross-linked ionic water-soluble polymers are cross-linked in the molecule, so the molecules do not easily spread in water, and should be less spread in water than linear polymers. However, as the degree of crosslinking increases, the viscosity when measured with a B-type viscometer (a type of rotational viscometer) increases. The cause is presumed to be due to friction or entanglement between the rotor of the B-type viscometer (rotor at the time of measurement) and the solution, but it is not exactly known. On the other hand, the viscosity of the crosslinked ionic water-soluble polymer in salt water decreases as the degree of crosslinking increases. Since the molecules are contracted by the cross-linking, it is considered that the influence is greatly influenced by a large amount of ions of the salt water. Therefore, for these reasons, the ratio of the two viscosity measurements increases as the degree of crosslinking increases. This relationship does not hold when cross-linking further progresses and becomes water-insoluble. When the cationic or amphoteric water-soluble polymer constituting the flocculation treatment agent comprising the water-in-oil emulsion in the present invention is used as the cross-linked water-soluble polymer, the ratio of the viscosity measurement value to the hardly dehydrated sludge However, 12 or more are preferable, and 15 or more may be more preferable.

In the present invention, as a method for producing an aggregating agent comprising a water-in-oil emulsion of a cationic or amphoteric water-soluble polymer, an ionic monomer or a nonionic monomer capable of copolymerization with an ionic monomer is used. Or a monomer mixture containing a crosslinkable monomer, water, an oily substance comprising at least water-immiscible hydrocarbon, an amount effective to form a water-in-oil emulsion and at least one HLB. It is synthesized by mixing various types of surfactants, stirring vigorously to form a water-in-oil emulsion and polymerizing.

  Examples of oily substances made of hydrocarbons used as dispersion media include paraffins, mineral oils such as kerosene, light oil, and middle oil, or hydrocarbons having characteristics such as boiling point and viscosity in substantially the same range as these. Synthetic oils or mixtures thereof may be mentioned. As content, it is the range of 20 mass%-50 mass% with respect to the water-in-oil type emulsion whole quantity, Preferably it is the range of 20 mass%-35 mass%.

The polymerization concentration of the monomer is in the range of 20 to 50% by mass, and the concentration and temperature of the polymerization are appropriately set depending on the monomer composition, the polymerization method, and the selection of the initiator.

Examples of at least one surfactant having an amount effective to form a water-in-oil emulsion and HLB are HLB 1-8 nonionic surfactants, specific examples of which include sorbitan monooleate Sorbitan monostearate, sorbitan monopalmitate and the like. When emulsified and polymerized with these low HLB surfactants, a hydrophilic surfactant called a phase inversion agent is added after the polymerization to make the emulsion particles covered with the oil film easy to become familiar with water, and the water-soluble The polymer is easily dissolved, diluted with water and used for each application. Examples of hydrophilic surfactants are cationic surfactants and HLB 9-15 nonionic surfactants, such as polyoxyethylene polyoxypropylene alkyl ethers and polyoxyethylene alcohol ethers.
When a high HLB surfactant is used, the emulsion emulsified to form a water-in-oil emulsion and polymerized may be compatible with water as it is, so that it may not be necessary to add a phase inversion agent. As high HLB surfactants, there are surfactants of HLB 9-20, and specific examples thereof are cationic surfactants and nonionic surfactants, such as polyoxyethylene alkyl ethers, polyoxyethylene alcohol ethers. And polyoxyethylene alkyl ester series. Specifically, polyoxyethylene (20) sorbitan trioleate, polyoxyethylene (6) sorbitan monostearate, polyoxyethylene (6) sorbitan monooleate and the like. By using a high HLB surfactant, it is possible to form a water-in-oil emulsion that can be dissolved in water after polymerization and at the time of dilution, particularly without the addition of a phase inversion agent. The addition rate of these surfactants is 0.5 to 10% by mass, preferably 1 to 5% by mass, based on the total amount of the water-in-oil emulsion.

The polymerization conditions are usually appropriately determined depending on the monomer used and the copolymerization mol%, and the temperature is in the range of 0 to 100 ° C. In particular, when the water-in-oil emulsion polymerization method is applied, it is carried out in the range of 20 to 80 ° C, preferably 20 to 60 ° C. For the initiation of polymerization, a radical polymerization initiator is used. These initiators may be either oil-soluble or water-soluble, and 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, and the like. Can be mentioned.

The polymerization is carried out under a nitrogen atmosphere with a polymerization initiator such as 2,2′-azobis (amidinopropane) dichloride or 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl). Propane] A water-soluble azo polymerization initiator such as dihydrochloride or a water-soluble redox polymerization initiator such as ammonium persulfate and sodium bisulfite in combination is added, and radical polymerization is performed with stirring.

For the cationic or amphoteric water-soluble polymer in the present invention, the total amount of the cationic monomers is 80 to 100 mol%, preferably 85 to 100 mol%, more preferably 90 to 100 mol%. Yes. This is because the medium and high moles are more effective than the low moles in reducing the water content of the sludge by reducing the anionic charge of the suspended particles in the sludge as much as possible. Usually, depending on the properties of the sludge, if the number of moles is too high, it may be difficult to obtain a high molecular weight, which may not be preferable. The present inventors have found that the dehydration effect is excellent due to the synergistic effect with the hydrophobic action by the hydrophobic group as described above. When the cationic or amphoteric water-soluble polymer in the present invention is completely dissolved in 4% by weight saline so that the polymer concentration is 0.5% by weight, the aqueous salt solution viscosity measured at 25 ° C. with a rotational viscometer is 15 mPa · s or more and 80 mPa · s or less, preferably 15 ma · s or more and 70 mPa · s or less. When the salt aqueous solution viscosity is lower than 15 mPa · s, the agglomeration performance is insufficient, and when it exceeds 80 mPa · s, the viscosity is increased and the dispersibility is lowered, which is not preferable. Moreover, as a result of the formation flocs becoming large and taking in excessive moisture, the dehydration effect may be reduced. The viscosity in a 4% by mass saline solution having a polymer concentration of 0.5% by mass is a value measured with a No. 2 rotor at 30 rpm (25 ° C.) in a B-type viscometer. The viscosity is a value measured with a No. 1 rotor and 60 rpm (25 ° C.). As a B-type viscometer, Tokyo Keiki make, B8M, etc. are used. The weight average molecular weight of the cationic or amphoteric water-soluble polymer in the present invention is preferably 2 million to 10 million, more preferably 2 million to 8 million, and even more preferably 3 million to 8 million. In addition, when calculating | requiring the weight average molecular weight in this invention, it measures using the static light scattering method.

In the present invention, the dehydrating property of the flocculating agent is improved by changing the cationic monomer represented by the general formula (1) and / or (2) of the cationic or amphoteric water-soluble polymer in the water-in-oil emulsion. A polymer obtained by increasing the molecular weight by adopting a water-in-oil emulsion polymerization method, an effect of having a cationic monomer represented by the general formula (3) Therefore, it is thought that it is based on being able to exhibit a favorable cohesion force also with respect to a hardly cohesive organic sludge. This is thought to have an effect on molecular weight, cation equivalent, balance between hydrophilicity and hydrophobicity, but in the present invention, these factors are used to control molecular weight, high cationicity and hydrophobic groups such as benzyl groups. It is considered that the hydrophobization could be controlled by introducing a specific range. It is considered that a remarkable water content reduction effect is obtained by the synergistic effect of the neutralization action of the cationic group and the hydrophobic action of the hydrophobic group such as the benzyl group.

The sludge applicable to the flocculant in the present invention is surplus sludge generated when biological treatment such as paper wastewater, chemical industrial wastewater, food industrial wastewater, etc., or organic sludge generated in the treatment of municipal sewage, human waste and industrial wastewater. (So-called raw sludge, surplus sludge, mixed raw sludge, digested sludge, coagulation / floating sludge, and mixtures thereof) are added to these sludges in an arbitrary concentration with water or added as a stock solution. Although the addition rate with respect to sludge changes with sludge seed | species and a dehydration model, it is 0.005-2.0 mass% normally with respect to sludge solid content. Moreover, you may use together with inorganic type coagulants, such as ferric chloride, ferric sulfate, poly ferric sulfate, PAC, and a sulfuric acid band.

The type of dehydrator to be used can correspond to a belt press, a centrifugal dehydrator, a screw press, a multi-disc dehydrator, a rotary press, a filter press and the like. It is particularly effective in screw presses and multiple disk type dehydrators that can be applied with a high pressing force.

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

  As samples for the sludge dewatering test, samples 1 to 7 of the water-in-oil emulsion of the cationic or amphoteric water-soluble polymer in the present invention were prepared by a conventional method of water-in-oil emulsion polymerization. Samples -8 to 16 outside the scope of the present invention were prepared by a conventional method of water-in-oil emulsion method (both concentrations were 40%). In addition, powder sample 17 and amidine-based water-soluble polymer (commercially available powder, ZP-700 manufactured by Hymo Co., Ltd., 0.5% by weight salt aqueous solution viscosity 8 mPa · s) were prepared. Table 1 shows the composition and physical properties of each sample.

(Table 1)
DMQ; acryloyloxyethyltrimethylammonium chloride DMBZ; acryloyloxyethyldimethylbenzylammonium chloride AAM; amount of acrylamide crosslinking agent; amount of methylenebisacrylamide added to monomer 0.2% by weight aqueous solution viscosity; 0.2% by weight high The molecular aqueous solution was measured with a B-type viscometer (25 ° C.).
0.5 mass% salt aqueous solution viscosity; 4 mass% sodium chloride was added to 0.5 mass% polymer aqueous solution, and after complete dissolution, measured with a B-type viscometer (25 ° C.)

(Example 2) A sludge dewatering test was carried out using sewage mixed raw sludge (pH 5.9, SS content 16000 mg / L, organic matter amount 81.2% by mass / SS, electric conductivity 164 mS / m). 200 mL of sludge was collected in a poly beaker, and 0.2 ppm by mass of the sample of Example 1 was added to the sludge SS content of 160 ppm. The beaker was transferred to the beaker and stirred 20 times, and then with a nylon filter cloth (# 202) Filtration was performed, and the filtrate amount after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 3 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 2.

(Comparative Test Example 1) The same sludge dewatering test was carried out using the same sludge as in Comparative Example 2. 200 mL of sludge was collected in a poly beaker, 0.2 ppm by mass of the comparative sample was added at 160 ppm to the sludge SS, the beaker was transferred and stirred 20 times, filtered through a nylon filter cloth (# 202), 60 The measurement of the filtrate amount after 2 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 3 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 2.

(Table 2)

(Example 3) A sludge dewatering test was carried out using sewage mixed raw sludge (pH 5.1, SS content 19250 mg / L, organic matter amount 84.4% by mass / SS, electric conductivity 233 mS / m). 200 mL of sludge was collected in a poly beaker, 0.2 ppm by mass of the sample of Example 1 was added to each sludge at a concentration of 100 ppm, the beaker was transferred and stirred 20 times, and then filtered with a nylon filter cloth (# 202). Filtration was performed, and the filtrate amount after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 3 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 3.

(Comparative Test Example 2) The same sludge dewatering test was carried out using the same sludge as in Example 3. 200 mL of sludge was collected in a poly beaker, 0.2 ppm by mass of the comparative sample was added to each sludge SS content of 100 ppm, the beaker was transferred and stirred 20 times, and then filtered through a nylon filter cloth (# 202). The amount of filtrate after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 3 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 3.

(Table 3)

(Example 4) A sludge dewatering test was carried out using sewage mixed raw sludge (pH 6.8, SS content 33750 mg / L, organic matter amount 78.5% by mass / SS, electric conductivity 162 mS / m). 200 mL of sludge was collected in a poly beaker, 0.2% by mass of the sample of Example 1 was added to the sludge SS content of 210 ppm, and after stirring for 30 seconds at a stirring speed of 1000 rpm in a CST measuring device, a nylon filter cloth was used. (# 202), and the filtrate amount after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 3 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 4.

(Comparative Test Example 3) Using the same sludge as in Example 4, a similar sludge dewatering test was carried out. 200 mL of sludge was collected in a poly beaker, 0.2 ppm by mass of the comparative sample was added at 250 ppm for each sludge SS, and after stirring for 30 seconds at a stirring rotation speed of 1000 rpm in a CST measuring device, a nylon filter cloth (# 202 The amount of filtrate after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 3 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 4.

(Table 4)

(Example 5) A sludge dewatering test was conducted using sewage digested sludge (pH 7.4, SS content 9750 mg / L, organic matter amount 71.8% by mass / SS, electric conductivity 457 mS / m). 200 mL of sludge was collected in a poly beaker, 0.2 mass% solution of the sample of Example 1 was added to each sludge SS content of 250 ppm, and after stirring for 60 seconds at a stirring rotation speed of 500 rpm in a CST measuring device, a nylon filter cloth was used. (# 202), and the filtrate amount after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 4 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 5.

(Comparative Test Example 4) Using the same sludge as in Example 5, a similar sludge dewatering test was carried out. 200 mL of sludge was collected in a poly beaker, 0.2 ppm by mass of the comparative sample was added to the sludge SS content of 250 ppm. After stirring for 60 seconds at a stirring rotation speed of 500 rpm in a CST measuring device, a nylon filter cloth (# 202 The amount of filtrate after 60 seconds was measured. After the measurement, the sludge filtered for 60 seconds was dehydrated at a press pressure of 4 kg / cm ² for 60 seconds, and the floc diameter and water content (dried at 105 ° C. for 20 hours) were measured. The results are shown in Table 5.

(Table 5)

In the example in which the sample of Example 1 of the present invention was added, the moisture content of the cake decreased and the amount of drainage increased in comparison with the comparative example in which the sample outside the scope of the present invention was added. It was confirmed that the coagulation treatment agent in was effective against organic sludge. On the other hand, when a sample outside the scope of the present invention is added, although the amount of filtrate may show the same level as the present invention, the moisture content of the cake often does not decrease, the specific cationic group of the present invention and the molar composition and By having the physical properties, it is considered that the synergistic effect of the charge neutralization action, the hydrophobic action and the cross-linking adsorption action of the suspended particles in the sludge was obtained.

Claims (3)

70-90 mol% of a cationic monomer represented by the following general formula (1) and / or (2), 10-20 mol% of a cationic monomer represented by the following general formula (3), 0-20 mol% of anionic monomer represented by formula (4), 0-20 mol% of nonionic monomer, and 0-50 ppm by weight of the crosslinkable monomer based on the monomer mixture In a cationic or amphoteric water-soluble polymer oil, the aqueous monomer mixture containing the body is dispersed in a dispersed phase, and an organic liquid immiscible with water is emulsion-polymerized with a surfactant to make the organic liquid a continuous phase. Aggregation treatment agent consisting of water-type emulsion.

General formula (1)
R ₁ is hydrogen or a methyl group, R ₂ and R ₃ are alkyl or hydroxyalkyl groups having 1 to 3 carbon atoms, R ₄ is hydrogen and an alkyl group having 1 to 3 carbon atoms, which may be the same or different, and A is oxygen or NH, B represents an alkylene group having 2 to 4 carbon atoms, _{X 1} ^- represents respectively an anion.

General formula (2)
R ₅ represents hydrogen or a methyl group, R ₆ and R ₇ represent an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group, and X ₂ ⁻ represents an anion.

General formula (3)
R ₈ is hydrogen or a methyl group, R ₉ and R ₁₀ are alkyl or hydroxyalkyl groups having 1 to 3 carbon atoms, R ₁₁ is an alkyl group or aryl group having 7 to 20 carbon atoms, A is oxygen or NH, B Represents an alkylene group having 2 to 4 carbon atoms, and X ₃ ⁻ represents an anion.

General formula (4)
R ₁₂ is hydrogen, methyl group or carboxymethyl group, Q is SO ₃ , C ₆ H ₄ SO ₃ , CONHC (CH ₃ ) ₂ CH ₂ SO ₃ , C ₆ H ₄ COO or COO, R ₁₃ is hydrogen or COOY ₂ , Y ₁ or Y ₂ represents hydrogen or a cation, respectively. The aggregation treatment agent according to claim 1, wherein the cationic or amphoteric water-soluble polymer has a viscosity of 15 to 80 mPa · s in a 4% by mass 4% by mass saline solution at 25 ° C. A method for dewatering sludge, comprising adding the aggregating agent according to claim 1 or 2 to sludge, mixing and coagulating, and then dehydrating with a dehydrator.