RU2222502C2 - Method of conditioning hydroxide sediments in natural and industrial waste waters - Google Patents

Abstract

FIELD: waste water treatment. SUBSTANCE: before being filtered off, hydroxide deposits formed in the course of reagent purification of natural and industrial waste waters are mixed with 0.01-0.2% of water-insoluble cationic copolymer of acrylamide with dialkylaminoalkyl (meth)acrylates or their hydrochloric acid or sulfuric acid salts, or their quaternary salts with dimethyl sulfate or methyl chloride, said copolymer containing 10-90 mol % cationic groups; and 0.00005-0.003% of polyacrylamide containing 1-30 mol % anionic groups. Amount of solid sediments after treatment is decreased by a factor of 1.3-1.8. EFFECT: improved environmental safety at the same filtration productivity. 2 cl, 2 tbl, 8 ex

Description

 The invention relates to the field of physico-chemical treatment of natural and industrial wastewater, in particular to methods for filtering hydroxide precipitates formed in the processes of reagent treatment of natural and industrial wastewater.

 In recent years, reagent treatment is widely used in the processes of water treatment and neutralization of industrial wastewater, accompanied by coagulation and sedimentation of suspended particles. Mineral coagulants, for example, aluminum, iron, magnesium, calcium salts, are added to the water. As a result of hydrolysis, metal hydroxides that are poorly soluble in water are formed, which are predominantly released on particles of water impurities, which contributes to the enlargement and precipitation of the latter. The precipitate is a highly moist mass of organomineral substances of different dispersion, combined with the help of hydroxide bonds into a single spatial structure with colloidal properties.

 The problem of using traditional coagulants in the processes of separating colloidal particles from natural water and industrial wastewater is the formation of large quantities of sludge, which is removed in the form of a hydroxide suspension. The destruction of these solid wastes is carried out by discharge into water bodies or landfills. In connection with the increasing requirements for environmental protection, industrial and municipal enterprises are faced with the task of finding ways to reduce the amount of solid waste.

 The main stage of water treatment, which determines the choice of subsequent operations and the efficiency of the process as a whole, is filtration, which is used to reduce humidity, and therefore the amount of precipitation, in order to reduce the cost of subsequent transportation and reduce the area of waste disposal. The choice of sludge filtration method and the efficiency of using this or that equipment primarily depends on the type and properties of the sludge being processed. The filtration efficiency is significantly increased due to additional modification of the condensed part in the treated water by treating it with reagents and excipients.

 When solving the environmental problems of communal and industrial enterprises, flocculants of high molecular weight acrylamide polymers deserve special attention. Among the advantages of using flocculants in practice, the preparation of municipal and industrial sludges with higher structural and mechanical characteristics, an increase in the rate and degree of their dehydration are especially emphasized.

 So, there is a known method for conditioning polyacrylamide with hydroxide precipitates formed during the treatment of wastewater from fine suspensions and dissolved or emulsified oils (oil products) before they are filtered on vacuum filters (L.N. Anokhina // Chemical and Petroleum Engineering, 1984, eleven). A hydroxide precipitate is obtained by mixing at a certain ratio of neutralized effluents containing chloride, carbonate and calcium oxide, with effluents containing dissolved or emulsified oils (petroleum products). When mixing, mutual coagulation of suspensions and oils occurs. After the introduction of polyacrylamide and a short settling in the radial sedimentation tanks, the effluent mixture is purified from suspensions and oils. The hydroxide precipitate deposited in the settlers is sent to a sludge compactor, where it thickens to a content of 6 g / l, and is filtered on drum vacuum filters.

 However, the obtained gel-like precipitate, adhering to the filter cloth, clogs the filter baffle of the drum vacuum filter. As a result, the filtering fabric often has to be regenerated, the duration of the protective effect of the filtering load decreases, and equipment downtimes increase. And, as a result, the performance of filtering equipment decreases.

 To intensify the filtration process, additional processing of the thickened part of the flocculated suspension is carried out. One of the promising methods for conditioning hydroxide sludge from natural and industrial wastewater is to treat them with polycomplexes of water-soluble polymers.

 A known method of conditioning a hydroxide precipitate formed during reactive wastewater treatment for the production of acrylic dispersions with anionic and cationic acrylamide polymers before filtering them (T. A. Bayburd et al. Intensification of the treatment of acrylate effluents with high molecular weight flocculants / Water supply and sanitary engineering, 1987, 8, s . 20-22).

This method is carried out as follows: a hydroxide suspension is obtained by introducing into the waste water containing 10-15 g / dm ^{3 of the} dispersed phase, with the stirrer switched on, a 42% alkali solution, after 5-7 minutes of stirring, a 10% solution of ferric chloride . The resulting fine suspension of coagulated iron hydroxide polymers is stirred for 7-10 minutes to complete coagulation, after which a 0.25% solution of the anionic acrylamide copolymer is introduced, followed by a 0.25% solution of the cationic acrylamide copolymer. The resulting suspension is heated to 50 ^o C and maintained under these conditions for 20-30 minutes, after which it is poured onto a capacitive filter with a filter baffle. Treated water is discharged into the sewer. The squeezed precipitate is discharged into a container.

As the anionic polymer of acrylamide, polymers are used containing in their chemical composition 90 mol.% Units of acrylamide and 10 mol.% Units of acrylic acid and having an intrinsic viscosity of 10 dl / g. The expendable dose of a water-soluble anionic flocculant is 20 g / DM ³ .

A polymer containing 90 mol% of acrylamide units and 10 mol% of dimethylaminoethyl methacrylate hydrochloride and having an intrinsic viscosity of 5 dl / g is used as a cationic acrylamide copolymer. The expendable dose of a water-soluble cationic flocculant is 20 g / dm ³ .

The expenditure dose of ferric chloride and sodium hydroxide are 1700 and 860 g / DM ³ respectively.

 With this method of conditioning the hydroxide precipitate formed during the reactive wastewater treatment of the production of acrylic dispersions by the combined action of temperature and high molecular weight flocculants, the filtering process of the hydroxide suspension is intensified, the filtration rate is increased by 15-20 times (compared with the filtration rate of the hydroxide suspension not treated with a water-soluble polycomplex acrylamide copolymers). The quality of the treated water meets the requirements for both its return to the production cycle, and when discharged to biochemical facilities. Get a large, porous, rubbery precipitate with a moisture content of 70-75 wt.%, Easily removed from the filter partition. This allows you to regenerate the filter cloth and reuse it in the filtering process.

 However, the process of conditioning the hydroxide precipitate formed during the reagent wastewater treatment for the production of acrylic polymers by this method is characterized by increased energy consumption.

 To intensify the process of filtering hydroxide precipitates, so-called filler materials are used. For example, dust from electrostatic precipitators and anionic acrylamide polymer in the amount of 0-200% and 0.2% of the dry mass of the precipitate, respectively, are introduced into precipitation before filtration (Lewandowski ZA // Arch. Ochr. Srodow, 1977, 2, 93-106 ) or powdered activated carbon and anionic and cationic acrylamide polymers (Application EPO 0129259, application. 09.04.84, publ. 27.12.84).

 The closest in technical essence is the method of conditioning hydroxide precipitates formed during the reagent purification of natural high-color waters, with filler material (lime or perlite) and polyacrylamide before filtering them (SV Yakovlev et al. Filtration dehydration of hydroxide precipitates of natural waters / Water supply and sanitary engineering, 1988, 3, pp. 12-14). Hydroxide precipitates are obtained after 10-25 mg / l aluminum sulphate is introduced into the high-color river water. The resulting precipitation is characterized by low water loss. To concentrate the thickened part, 0.03-0.1% (by weight of dry matter) of polyacrylamide is introduced into the obtained hydroxide dispersion and sent to settle in a radial thickener, where it thickens to a content of 2-5 wt.% Of dry matter. Then the clarified purified water is pumped out. A feature of the second stage of processing condensed sediments with a moisture content of 95-98% by excipients is the conversion of gel-like hard-to-filter precipitates into structured systems.

 In the joint processing of PAA sediments and lime, PAA is first introduced into the sediment, then lime. When using perlite or fine waste from the production of perlite with a particle size of less than 250 microns, perlite is first introduced into the precipitate, then PAA.

 Reagent dose ratios necessary for structuring precipitation are: PAA: CaO = 1: (20-200); PAA: perlite = 1: (100-300). Consumable doses of filler materials are: 0.25-2.5 wt.% CaO or 0.6-3.75 wt.% Perlite.

 When filtering sediments on a chamber and belt filter press, a precipitate is obtained on a filter with a moisture content of 67-84%. This ensures a good knife removal of sediment from the fabric. The property of increased hydrophobization acquired by structured sediments makes it possible to carry out loading and unloading operations and transport precipitation of low-turbid colored water with a moisture content of up to 83-84%.

 However, when conditioning the hydroxide precipitate with lime or perlite before filtration, the amount of solid precipitate process waste increases by 50-70%. And as a result, the area of their burial is increasing.

 The objective of the invention is the dehydration of hard-to-filter hydroxide sludge formed during the reagent treatment of natural and industrial wastewater, in a way with high productivity and environmental safety.

 The technical result of this invention is to reduce the amount of solid sludge while maintaining the filtration properties of the conditioned sludge.

 The proposed method is as follows. 0.01-0.2 wt.% Water-insoluble cationic acrylamide polymer, 0.00005-0.003 wt.% Acrylamide polymer are introduced into the coagulator with a hydroxide suspension resulting from the reactive purification of natural or industrial wastewater and filtered. The purified water is discharged into the sewer or used as recycled water in an industrial process. The squeezed precipitate is discharged into a container.

 Filtration is carried out by known methods, for example, using a nutsche filter or centrifugal forces, squeezing a suspension of hydroxide precipitates by means of a pump, under vacuum on drum and disk filters, under pressure on filter presses, belt filters and precoated filters. Non-woven material, belting, nylon (GOST 4403, article 48), etc. are used as a filtering partition.

 According to the proposed method, conditioning is carried out before filtering the hydroxide precipitates formed during the reagent purification of natural and waste waters of chemical, paint and varnish, galvanic industries, utilities under the influence of coagulants with an expendable dose of up to 2000 mg / l of metal hydroxide.

 Conditioning the hydroxide precipitate with a water-insoluble cationic acrylamide copolymer before filtration increases the environmental safety of the process by reducing the amount of solid precipitate while maintaining high process performance (filtration properties of the conditioned precipitate).

 Acrylamide polymers produced according to TU 6-02-00209912-61-97 or TU 6-02-00209912-41-94 contain 70-99 mol% of acrylamide and 1-30 mol% of sodium acrylate in their chemical composition and have intrinsic viscosity of 6-20 dl / g.

 Water-insoluble cationic acrylic copolymers of acrylamide and dialkylaminoalkyl (meth) acrylates, or their salts with hydrochloric or sulfuric acid, or their quaternized salts of dimethyl sulfate or methyl chloride, manufactured according to TU 6-02-00209912-59-96, contain 10 in their chemical composition -90 mol.% Cationic groups. Cationic copolymers have a degree of absorption of distilled water of 40-200 g / g and a water-soluble part of 3-10%.

A comparative assessment of the effectiveness of the method of conditioning the precipitate before filtration is carried out according to the test method in a laboratory setup by filtration on a Buchner funnel with a discharge of 0.4-0.5 kg / cm ² , which is maintained constant during the experiment. The filtering area of the white ribbon paper filter is 38 • 10 ^-4 m ² . When filtering, a comparative assessment of the obtained technical result of reducing the amount of solid sludge and preserving the filtering properties of the sludge, conditioned by known and proposed methods, is carried out.

 The environmental safety of the process is judged by the amount of solid sludge (g / kg), calculating it by the ratio of the solids content of the sludge after filtration to the initial amount of conditioned sludge.

 The preservation of the filtration properties of the sludge conditioned by the known and proposed methods is evidenced by equal values of the filtration time and water loss of the hydroxide precipitate.

Sludge yield (W,%) is calculated by the ratio of the amount of filtered water (V, g) to the initial amount of conditioned sludge (V _о , g): W = (V / V _о ) • 100.

 Distinctive features of the proposed method for conditioning hydroxide precipitation before filtration is the use of a water-insoluble cationic acrylamide copolymer as an additive material; chemical composition and consumption rates of a water-insoluble cationic copolymer of acrylamide and acrylamide polymer.

 The use of a water-insoluble cationic acrylamide copolymer in the method of conditioning hydroxide precipitates formed in the process of reagent treatment of natural and industrial wastewater is not described in the scientific literature before filtration.

 The set of essential features of the invention ensures the achievement of a new technical result, improving environmental safety while maintaining high productivity of the filtering process of conditioned hydroxide precipitation of natural and industrial wastewater. The amount of solid precipitation decreases by 1.3-1.8 times. The filtration properties of the conditioned hydroxide precipitate do not change.

 The feasibility of the method is illustrated by the following examples.

Example 1
100 g of a 3.3% hydroxide precipitate formed during the reactive purification of the Volga water under the action of aluminum sulfate with an expendable dose of 7 mg / l according to Al ₂ O ₃ is introduced into a 0.25 liter capacity. At room temperature and stirring at a speed of 100 rpm, 1.65 g of perlite and 1.5 ml of a 0.2% solution of acrylamide polymer containing 95 mol.% Acrylamide and 5 mol.% Sodium acrylate are successively introduced into the hydroxide precipitate and having an intrinsic viscosity of 12 dl / g. The costs of the filler material and the acrylamide polymer are 1.65 and 0.003 wt.%, Respectively. The precipitate was stirred for 2 minutes and filtered on a Buchner funnel under vacuum.

 Assess the effectiveness of conditioning the hydroxide precipitate in a known manner by its filtration properties and the amount of solid precipitate.

 Similarly spend conditioning hydroxide precipitate of the proposed method. In a 0.25 liter capacity at room temperature and stirring at a speed of 50-100 rpm in 100 g of hydroxide precipitate with a dry matter mass fraction of 3.3%, 0.2 g of a water-insoluble cationic acrylamide copolymer containing 30 mol.% Acrylamide and 70 mol% of dnomethylaminoethyl methacrylate hydrochloride and having a degree of absorption of distilled water of 80 g / g and a water-soluble part of 10%, and 1.5 ml of a 0.2% solution of the above acrylamide polymer. The costs of the filler material and the acrylamide polymer are 0.2 and 0.003 wt.%, Respectively. The precipitate is stirred for 2 minutes and filtered on a Buchner funnel under vacuum.

 Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the amount of solid sediment.

 Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in table 1.

The experiments were carried out on a hydroxide precipitate formed during the reagent purification of the Volga water. According to the technological regulations of the city water treatment plant of the Municipal Unitary Enterprise “Saratovvodokanal”, the Volga water (turbidity 45 mg / l and color 35 grad) are treated with alkali (dose 1 V mg / l), aluminum sulfate (7 mg / l according to Al ₂ O ₃ ) and polyacrylamide (0.3 mg / l). After settling for 20 minutes, the purified water is drained, and the hydroxide precipitate is concentrated for 8 hours, draining the water released during the settling.

Example 2
Analogously to example 1, the hydroxide precipitate formed during the reactive purification of river water under the action of aluminum sulfate with an expendable dose of 9 mg / L in accordance with Al ₂ O ₃ is conditioned. 2.5 g of perlite and 2 ml of a 0.2% solution of acrylamide polymer containing 97.5 mol.% Acrylamide and 2.5 mol.% Sodium acrylate are successively introduced into 100 g of a hydroxide precipitate with a mass fraction of dry matter of 5%; having an intrinsic viscosity of 14 dl / g. The consumption of filler material and acrylamide polymer are respectively 2.5 and 0.004 wt.% And filtered.

 Assess the effectiveness of conditioning the precipitate in a known manner by its filtration properties and the content of solid sediment.

 Similarly, the hydroxide precipitate is conditioned by the proposed method with the successive introduction of 0.2 g of a water-insoluble cationic acrylamide copolymer containing 50 mol.% Acrylamide and 50 mol. % dimethylaminoethyl methacrylate hydrochloride and having a degree of absorption of distilled water of 80 g / g and a water-soluble part of 10%, and 2 ml of a 0.2% solution of the above acrylamide polymer. The costs of the filler material and the acrylamide polymer are 0.2 and 0.004 wt.%, Respectively.

 Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment.

 Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in table 1.

The experiments were carried out on a hydroxide precipitate formed during the reagent purification of high-color river water. According to the technological regulations of the metafraks JSC technological water treatment station, river water (turbidity 10 mg / l and color color 186 degrees) is treated with alkali (dose 15 mg / l), aluminum sulfate (9 mg / l according to Al ₂ O ₃ ) and polyacrylamide (0.3 mg / l). After settling for 20 minutes, the purified water is drained and used in the technological process of the enterprise, and the hydroxide precipitate is concentrated for 48 hours, draining the water released during the settling.

Example 3
Analogously to example 1, the hydroxide precipitate formed during the reagent purification of technological recycled water under the action of aluminum sulfate with an expendable dose of 78 mg / l in Al ₂ O ₃ is conditioned. In 100 g of hydroxide precipitate with a mass fraction of dry matter of 2%, 1.5 g of perlite and 0.5 ml of a 0.2% solution of acrylamide polymer containing 80 mol.% Acrylamide and 20 mol.% Sodium acrylate and having a characteristic viscosity 10 dl / g and filtered. The costs of the filler material and the acrylamide polymer are respectively 1.5 and 0.001 wt.%.

 Assess the effectiveness of conditioning the precipitate in a known manner by its filtration properties and the content of solid sediment.

 Similarly, the hydroxide precipitate is conditioned by the proposed method with the successive introduction of 0.2 g of a water-insoluble cationic acrylamide copolymer containing 70 mol.% Acrylamide and 30 mol. % dimethylaminoethyl methacrylate hydrochloride and having a degree of absorption of distilled water of 40 g / g and a water-soluble part of 3%, and 0.5 ml of a 0.2% solution of the above acrylamide polymer. The costs of the filler material and the acrylamide polymer are respectively 0.2 and 0.001% wt. %

 Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment.

 Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in table 1.

The experiments were carried out on a hydroxide precipitate formed during the reagent purification of technological recycle water for the production of dyes. According to the technological regulations of the clarification station of JSC "Pigment", the processing of technological water (containing 4.2 mg / l of Fe ions, 32 mg / l of suspended solids and having pH-7, color 425 degrees COD-230 mg / l O ₂ ) is carried out alkali (dose 130 mg / l), aluminum sulfate (78 mg / l according to Al ₂ O ₃ ) and polyacrylamide (1 mg / l). After settling for 24 hours, the purified water is drained and used in the circulating water supply system of the enterprise for technological purposes.

Example 4
The hydroxide sludge formed during the reagent wastewater treatment of galvanic production under the influence of milk of lime with an expendable dose of 1500 mg / L in CaO is conditioned. 75 g of a 1% solution of milk of lime and 1.5 ml of a 0.1% solution of acrylamide polymer containing 85 mol.% Acrylamide and 15 mol.% Sodium acrylate and having an intrinsic viscosity are successively introduced into 500 ml of wastewater with stirring. 14 dl / g The costs of the filler material and the acrylamide polymer are respectively 0.15 and 0.0003 wt.%. After 5 minutes, stirring was stopped and held for 20 minutes. The purified water is drained, and the hydroxide precipitate is filtered.

 Assess the effectiveness of conditioning the precipitate in a known manner by its filtration properties and the content of solid sediment.

 Similarly, the hydroxide precipitate is conditioned before filtration by the proposed method with successive introduction into wastewater previously neutralized to pH-9.5 with an aqueous solution of sodium hydroxide, 0.1 g of a water-insoluble cationic acrylamide copolymer containing 65 mol.% Acrylamide and 35 mol.% Hydrochloric acid dimethylaminoethyl methacrylate and having a degree of absorption of distilled water of 200 g / g and a water-soluble part of 10%, and 1.5 ml of a 0.1% solution of the above acrylamide polymer. The costs of the filler material and the acrylamide polymer are 0.02 and 0.0003 wt.%, Respectively.

 Conduct the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment.

 Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in table 1.

 The experiments were carried out on a hydroxide precipitate formed during the reagent treatment of galvanic wastewater in accordance with the technological regulations of the treatment plants of AOOT MARS Plant. Wastewater contains 20 mg / l of nickel ions and has pH-4.

Example 5
The hydroxide precipitate formed during the reactive wastewater treatment of the production of acrylic dispersions under the action of ferric chloride with an expendable dose of 1700 mg / L in accordance with Fe ₂ O _{3 is} conditioned. At room temperature and stirring at a speed of 100 rpm in a 500 ml hydroxide suspension with a mass fraction of dry matter of 1.5%, 3.75 g of perlite and 1.8 ml of a 0.2% solution of acrylamide polymer containing 80 mol . % acrylamide and 20 mol.% sodium acrylate and having an intrinsic viscosity of 11 dl / g. The costs of filler material and acrylamide polymer are 0.75 and 0.0007 wt.%, Respectively. Stirred for 2 minutes and filtered.

 Assess the effectiveness of conditioning the precipitate in a known manner by its filtration properties and the content of solid sediment.

 Similarly, the hydroxide precipitate is conditioned by the proposed method with the successive introduction of 0.2 g of a water-insoluble cationic acrylamide copolymer containing 90 mol.% Acrylamide and 10 mol.% Diethylaminoethyl methacrylate and having a degree of absorption of distilled water of 40 g / g and a water-soluble part 3 and 1.8 ml of a 0.2% solution of the above acrylamide polymer. The costs of the filler material and the acrylamide polymer are 0.04 and 0.0007 wt.%, Respectively. The precipitate was stirred for 2 minutes and filtered.

 Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment.

 Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in table 1.

The experiments were carried out on a hydroxide suspension formed during the reagent wastewater treatment of the production of acrylic dispersions. According to the technological regulations of the installation of the production of acrylic dispersions of the Federal State Unitary Enterprise “Saratov Scientific Research Institute of Polymers”, wastewater treatment (with a content of 12,000 mg / l of fine impurities of acrylic polymers of 216 mg / l of oil products (anionic surfactant), and having a pH of 6.1, COD - 15960 mg / l O ₂ ) is carried out with alkali (dose 1600 mg / l) and ferric chloride (1700 mg / l according to Fe ₂ About ₃ ).

Example 6
The hydroxide precipitate formed during the reagent purification of the production wash water from the use of acrylic dispersions under the action of ferric chloride is conditioned with an expendable dose of 400 mg / L according to Fe ₂ O ₃ . At room temperature and stirring at a speed of 100 rpm, in a 500 ml hydroxide suspension with mass moles of dry matter 0.19%, 0.37 g of perlite and 0.6 ml of a 0.2% solution of acrylamide polymer containing 70 mol % acrylamide and 30 mol% sodium acrylate and having an intrinsic viscosity of 12 dl / g. The costs of the filler material and the acrylamide polymer are 0.075 and 0.0002 wt.%, Respectively. Stirred for 2 minutes and filtered.

 Assess the effectiveness of conditioning the precipitate in a known manner by its filtration properties and the content of solid sediment.

 Similarly, the hydroxide precipitate is conditioned by the proposed method with the sequential introduction of 0.05 g of a water-insoluble cationic acrylamide copolymer containing 10 mol.% Acrylamide and 90 mol.% Methyl chloride diethylaminoethyl methacrylate and having a degree of absorption of distilled water of 65 g / g and a water-soluble part of 10%, and 0.6 ml of a 0.2% solution of the above acrylamide polymer. The costs of the filler material and the acrylamide polymer are 0.01 and 0.0002 wt.%, Respectively.

 Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment.

 Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in table 1.

The experiments were carried out on a hydroxide suspension formed during the reagent wastewater treatment of the production of acrylic dispersions. According to the technological regulations of the wash water treatment plant for the production of sticky laminate based on acrylic emulsion, CJSC “VEROPHARM”, wastewater treatment (containing 150 mg / l of fine admixtures of acrylic polymers, 20 mg / l of oil products (anionic surfactant), and having a pH of 7, 1, COD - 2600 mg / l O ₂ ), carried out by alkali (dose 400 mg / l) and ferric chloride (400 mg / l according to Fe ₂ About ₃ ).

Example 7
The hydroxide precipitate formed during the reagent cleaning of the spent drilling fluids in oil production processes under the influence of aluminum sulfate with an expendable dose of 200 mg / L in accordance with Al ₂ O _{3 is} conditioned. At room temperature and stirring at a speed of 100 rpm in a 500 ml hydroxide suspension with a mass fraction of dry matter of 0.1%, 0.35 g of perlite and 0.25 ml of a 0.1% solution of acrylamide polymer containing 90 mol . % acrylamide and 10 mol.% sodium acrylate and having an intrinsic viscosity of 12 dl / g. The costs of the filler material and the acrylamide polymer are 0.07 and 0.0005 wt.%, Respectively. After 5 minutes, stirring is filtered. Assess the effectiveness of conditioning the precipitate in a known manner by its filtration properties and the amount of solid sediment.

 Similarly, the hydroxide precipitate is conditioned before filtration by the proposed method with 0.05 g of a water-insoluble cationic acrylamide copolymer containing 70 mol.% Acrylamide and 30 mol.% Methyl chloride diethylaminoethyl methacrylate and having a degree of absorption of distilled water of 65 g / g and water part of 10%, and 0.25 ml of a 0.1% solution of the above acrylamide polymer. The costs of filler material and acrylamide polymer are 0.01 and 0.0005 wt.%, Respectively.

Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment. Comparative data on the filtration properties of the hydroxide precipitate, conditioned prior to filtration by known and proposed methods, and the solid content of the precipitate are shown in Table 1. The experiments were carried out on a hydroxide suspension formed during the reactive purification of spent drilling fluids in oil production processes containing 500 mg / l of drilling mud under the action 200 mg / l Al ₂ About ₃ .

Example 8
A comparative assessment is made of the effectiveness of conditioning the precipitate by known and proposed methods under the influence of filler material (perlite and various water-insoluble cationic acrylamide copolymers) and acrylamide polymers with different chemical compositions.

Analogously to example 1, the hydroxide precipitate formed during the reagent purification of the Volga water under the action of aluminum sulfate with an expendable dose of 7 mg / L in Al ₂ O ₃ is conditioned. 1.65 g of perlite and 1.5 ml of a 0.2% solution of acrylamide polymer containing 9.5 mol.% Acrylamide and 5 mol.% Acrylate are sequentially introduced into 100 g of a hydroxide precipitate with a mass fraction of dry matter of 3.3% sodium and having an intrinsic viscosity of 12 dl / g, and filtered. The costs of the filler material and the acrylamide polymer are 1.65 and 0.003 wt.%, Respectively.

 Assess the effectiveness of conditioning the hydroxide precipitate in a known manner by its filtration properties and the amount of solid precipitate.

 Similarly, the hydroxide precipitate is conditioned by the proposed method with the sequential introduction of calculated amounts of a water-insoluble cationic acrylamide copolymer having a distillation water absorption of 80 g / g and a water-soluble part of 10%, and a 0.2% solution of acrylamide polymer having a characteristic viscosity of 12 for / g The costs of the filler material and the acrylamide polymer are 0.2-0.01 and 0.00005-0.003 wt.%, Respectively.

 Assess the effectiveness of conditioning the precipitate of the proposed method according to its filtration properties and the content of solid sediment.

 Comparative data on the filtration properties of a hydroxide precipitate, conditioned before filtration by a known method and the proposed method under the action of various water-insoluble cationic copolymers of acrylamide and acrylamide polymers, and the solid content of the precipitate are shown in table 2.

Claims (2)

1. The method of conditioning the hydroxide precipitation of natural and industrial wastewater with filler material and acrylamide polymer before filtering, characterized in that as a filler material, a water-insoluble cationic copolymer of acrylamide and dialkylaminoalkyl (meth) acrylates, or their salts with hydrochloric or sulfuric acid, or their quaternized salts of dimethyl sulfate or methyl chloride, containing in its chemical composition 10-90 mol.% cationic groups, and using acrylamide as a polymer polymer containing 1-30 mol.% anionic groups is removed. 2. The method according to claim 1, characterized in that the water-insoluble cationic acrylamide copolymer and acrylamide polymer are used in an amount of 0.01-0.2 wt.% And 0.00005-0.003 wt.%, Respectively.

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