JPH06335605A - Treating agent for inorganic fine particle containing waste water and teatment of waste water - Google Patents

Abstract

PURPOSE:To form a compact floc excellent in flocculation ability by using a treating agent for an inorganic fine particle-containing waste water, consisting of a polyacrylamide based high polymer flocculant and an alkali metal carbonate. CONSTITUTION:An aq. solution of the treating agent consisting of the polyacryamide based high polymer flocculant and the alkali metal carbonate is added into an inorganic fine particle-containing waste water line. The agent has excellent flocculation ability, forms the compact floc and is capable of suppressing cratering phenomenon due to hydraulic force. And the treating agent is capable of suppressing the generation of calcium carbonate scale due to the increase in pH of the waste water after treatment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wastewater treating agent containing inorganic fine particles such as dust collecting water and crushed stone washing water, and a wastewater treating method. More specifically, the present invention provides a treatment for wastewater containing inorganic fine particles, which has excellent flocculating ability, does not cause a spring phenomenon due to the force of water in the formed flocs, and does not require addition of a pH adjusting agent. Agent and its wastewater treatment method.

[0002]

2. Description of the Related Art Conventionally, waste water containing inorganic fine particles such as dust collecting water and crushed stone washing water has been treated with an inorganic coagulant, a polymer coagulant, or a combination thereof. When treating such wastewater using an inorganic coagulant, the pH of the wastewater cannot be formed because when the inorganic coagulant is added to the wastewater, the wastewater becomes acidic and the flocs of hydroxide cannot be formed. It is necessary to add a pH adjusting agent to raise the temperature. Therefore, when treating wastewater with an inorganic coagulant, a pH adjuster is always used together, and after adding the inorganic coagulant to the wastewater, the pH is adjusted.
Wastewater is treated by adding regulators. As such an inorganic coagulant, polyaluminum chloride, aluminum sulfate, ferric sulfate, ferric chloride and the like are known. Further, sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, sodium carbonate and the like are used as the pH adjusting agent used in combination with the inorganic coagulant.

It is known that the action of the inorganic coagulant is that when dissolved in water, it forms a complex, neutralizes the charge of floating particles, and strongly adsorbs the particles. as a result,
Suspended particles such as inorganic fine particles will be removed. On the other hand, when treating such wastewater using a polymer flocculant, it is not necessary to use a pH adjuster together, because the wastewater does not become acidic even if the polymer flocculant is put into the wastewater. , Can be used alone as a wastewater treatment agent. Polymeric flocculants are classified into strong anionic, medium anionic, cationic and nonionic. Strong anionic polymer flocculants include sodium polyacrylate, and medium anionic polymer flocculants include partial hydrolysis products of polyacrylamide, copolymers of acrylamide and sodium acrylate, and acrylamide and acrylic acid. There is a copolymer of sodium and sodium 2-acryloylamino-2-methylpropanesulfonate. As the cationic polymer flocculant, polyvinyl imidazoline, polyalkylamino acrylate or methacrylate,
And Mannich modified products of polyacrylamide.
Further, examples of the nonionic polymer flocculant include polyacrylamide and polyethylene oxide.

Generally, the action of a polymer coagulant to agglomerate fine particles of a turbid component into a large lump called floc is as a function of agglomeration by neutralization of surface charge of particles and agglomeration by interparticle crosslinking (adhesion). The two effects of are considered. The aggregating action due to cross-linking between particles is an action peculiar to the polymer aggregating agent. Since the polymer flocculant has this effect, it can form much larger flocs than the inorganic flocculant. Therefore, there is an advantage that the effect can be exhibited with an amount smaller than that of the inorganic coagulant, for example, an amount of about 1/30 to 1/200. Furthermore,
Almost all polymer flocculants decompose into gas when incinerated, so that they have the advantage that no ash remains.

Recently, the most common method is to treat wastewater by using a polymer coagulant and an inorganic coagulant together. When the polymer coagulant and the inorganic coagulant are used in combination, it is necessary to add a pH adjuster for the same reason as when the inorganic coagulant is used alone. Waste water containing inorganic fine particles such as dust collection water and crushed stone washing water is often positively charged. Therefore, generally, anionic or nonionic polymer flocculants are often used for treating wastewater. As the anionic polymer flocculant, a hydrolysis rate of 40 has hitherto been used.
Polyacrylamide-based polymer flocculants up to mol% account for about 80% of the total demand.

In the case of treating negatively charged wastewater, a method of treating with a cationic polymer coagulant or a combination of an inorganic coagulant and a pH adjusting agent is used to neutralize the charge of the wastewater. Then, a method of treating with an anionic, cationic or nonionic polymer flocculant is performed. As a method for treating wastewater using a polymer flocculant, generally, an aqueous solution containing the polymer flocculant in an amount of 0.1 to 0.2% by weight is prepared, and the aqueous solution is stirred in the wastewater. A method of gradually inserting is used.

The amount of the inorganic coagulant, the pH adjuster, the polymer coagulant, etc. added is, for example, polyaluminum chloride as the inorganic coagulant and sodium carbonate as the pH adjuster, and the waste water containing the inorganic fine particles is used. When treating, it is common to add about 50 ppm of polyaluminum chloride and about 20 ppm of sodium carbonate. Further, for example, when polyacrylamide partial hydrolyzate is used as the polymer coagulant, polyaluminum chloride is used as the inorganic coagulant, and sodium carbonate is used as the pH adjuster, the polyacrylamide partial hydrolyzate is added in an amount of about 1 to 2 ppm. Aluminum chloride approx. 50 ppm and sodium carbonate approx. 10 ppm
It is common to add and treat.

[0008]

However, when treating wastewater using an inorganic coagulant, the inorganic coagulant does not have a long molecular chain like a polymer coagulant. The effect of cross-linking is small and only small flocs can be formed. Therefore, since the formed flocs are small, the flocs are light and difficult to settle, and there is a problem that a spring phenomenon due to the force of water occurs.

Further, the flocs formed when the waste water is treated by using the inorganic coagulant and the polymer coagulant together as described above, or when the waste water is treated by using the polymer coagulant alone. , There is no tightness because it is not strongly aggregated. Since there is no tightness of the formed flock, there is a problem that, like the small flock, the flock is light and difficult to settle, and a spring phenomenon due to the force of water occurs. Even if the addition amount of the aggregating agent used is increased, on the contrary, the particle dispersion effect is exhibited, and these problems cannot be solved. Further, when a large amount of the inorganic coagulant is used, a large amount of the pH adjusting agent is required accordingly.

Further, when the waste water is treated by using the inorganic coagulant alone or in combination with the polymer coagulant, the waste water p
In order to raise H, it is necessary to add a large amount of pH adjusting agent. When a large amount of pH adjusting agent is used for treating wastewater such as crushed stone washing water that is recycled and reused, the pH of the wastewater becomes high, which causes calcium carbonate scale to be generated. There is a problem that the gravel washed by reusing the wastewater treated with a large amount of the pH adjuster remains in the state where the mud adheres, which lowers the commercial value of the gravel.

In addition, when the crushed stone washing water is treated with these flocculants as described above, the water content of the precipitate becomes high, which causes a problem when the precipitate is used as a cement admixture.

[0012]

According to the present invention, there is provided a treatment agent for wastewater containing inorganic fine particles, which comprises a polyacrylamide polymer flocculant and an alkali metal carbonate. Further, according to the present invention, a method for treating wastewater containing inorganic fine particles, characterized in that an aqueous solution of a treatment agent comprising a polyacrylamide polymer flocculant and an alkali metal carbonate is added to a wastewater line containing inorganic fine particles. Will be provided.

The polymer flocculant is a polymer agent used for efficiently separating fine suspended particles that cause pollution from water, and collects small particles that are difficult to separate from water. It is used to make it easy to separate into a lump. In the following description of the present invention, wastewater means wastewater containing inorganic fine particles, and such wastewater includes, for example, dust collecting water, crushed stone washing water, pulp cooking liquor recovery process liquid and the like.

The polyacrylamide polymer flocculant used in the present invention may be any of the anionic or nonionic polyacrylamide polymer flocculants generally used in the art, and two or more of these may be used. Mixtures may be used. Examples of the nonionic polyacrylamide-based polymer flocculant include polyacrylamide, and examples of the anionic polyacrylamide-based polymer flocculant include a polyacrylamide partial hydrolyzate obtained by partially hydrolyzing a nonionic polyacrylamide, Copolymer of polyacrylamide and sodium acrylate, acrylamide and sodium acrylate 2-
Examples thereof include acryloylamino-2-methylpropanesulfonic acid sodium copolymer, sodium polyacrylate, and the like. Among these, nonionic polyacrylamide, or medium anionic polyacrylamide, polyacrylamide partial hydrolyzate, copolymer of acrylamide and sodium acrylate, or acrylamide, sodium acrylate and 2-acryloylamino- It is preferable to use a copolymer of sodium 2-methylpropanesulfonate, or a mixture of two or more thereof. In the following description of the present invention, sodium 2-acryloylamino-2-methylpropanesulfonate is abbreviated as AMPS.

Further, in order to crosslink between the inorganic fine particles in the waste water to form a strong aggregate (floc), the polyacrylamide polymer flocculant used preferably has a large molecular weight. Therefore, the molecular weight of the polyacrylamide polymer flocculant used in the present invention is, for example, 5,000,000 to 10,000,000 for polyacrylamide and 10,000,000 to 22 for polyacrylamide partial hydrolyzate.
Million, 8 to 22 million for polyacrylamide / sodium acrylate copolymer, 800 for acrylamide / sodium acrylate / AMPS copolymer
Those in the range of 10 to 20 million are suitable.

The polyacrylamide partial hydrolyzate used in the present invention has different aggregation ability depending on the degree of hydrolysis. The relationship between the degree of hydrolysis and the aggregation ability is
In general: A slight hydrolysis at first reduces the aggregating ability. However, as the hydrolysis proceeds further, the aggregating ability begins to improve, reaching a maximum at about 33 mol%, and beyond that, the anionic property becomes stronger as the hydrolysis rate increases, and the aggregating ability tends to decrease.

Therefore, the polyacrylamide partial hydrolyzate used in the present invention preferably has a hydrolysis rate of 40 mol% or less. The acrylamide / sodium acrylate copolymer and the acrylamide / sodium acrylate / AMPS copolymer used in the present invention may be either graft copolymers or block copolymers.

The alkali metal carbonate used in the present invention includes potassium carbonate, sodium carbonate and lithium carbonate, and potassium carbonate and sodium carbonate are preferable. The alkali metal carbonate may be used as a mixture of two or more kinds. The blending ratio of the polyacrylamide-based polymer flocculant and the alkali metal carbonate in the treatment agent for wastewater containing inorganic fine particles of the present invention,
19: 1 to 2: 8 (weight ratio) is suitable, and 9: 1 to
5: 5 (weight ratio) is preferable.

The treating agent of the present invention can be prepared by mixing the polyacrylamide polymer flocculant and the alkali metal carbonate at a desired ratio (weight ratio) using a blender or the like. According to the treatment method of the present invention, an aqueous solution of a treatment agent consisting of a polyacrylamide-based polymer flocculant and an alkali metal carbonate is prepared in advance, and the prepared treatment solution is treated with wastewater containing inorganic fine particles. Wastewater treatment is carried out by adding to the wastewater line (before thickener).

In the present invention, it is essential to prepare an aqueous solution of a polyacrylamide polymer flocculant and a treatment agent comprising an alkali metal carbonate in advance and add the prepared aqueous solution to waste water. Even if an aqueous solution of a polyacrylamide polymer flocculant and an aqueous solution of an alkali metal carbonate are separately prepared and these aqueous solutions are simultaneously added to the waste water, the desired effect cannot be obtained.

In the present invention, the concentration of the aqueous solution of the polyacrylamide polymer flocculant and the treating agent comprising the alkali metal carbonate before addition to the wastewater is 0.01 to 5
Weight percent is suitable and 0.1 to 2 weight percent is preferred. In addition, in the present invention, the amount of the aqueous solution of the treating agent prepared as described above is 0.1 when added to the wastewater.
-30 ppm is suitable and 0.1-10 ppm is preferred.

The treatment agent comprising the polyacrylamide polymer flocculant and the alkali metal carbonate of the present invention is preferably stored in a powder state, but may be stored in an aqueous solution state. The concentration when stored as an aqueous solution may be 2% by weight or more, but it is preferable to store it as a solution having a concentration as high as possible. The inorganic fine particle-containing wastewater treatment agent of the present invention is, for example, a cationic polymer flocculant, or a polymer flocculant such as anionic or nonionic polymer flocculant, an inorganic flocculant, and a scale inhibitor. , Other additives such as a corrosion inhibitor may be contained, or these additives may be used in combination with the treating agent of the present invention.

[0023]

【Example】

1. Field test (crushed stone washing water) (Test method) 160 kg of polyacrylamide partial hydrolyzate (molecular weight: 16 million) with a hydrolysis rate of 25 mol% and 40 kg of sodium carbonate were mixed using a blender,
A treating agent of the present invention was prepared in which the mixing ratio of the polyacrylamide polymer flocculant and the alkali metal carbonate was 8: 2 (weight ratio). Thereafter, water was added to 5 kg of the prepared treating agent to dissolve it to prepare 5 tons, thereby preparing a 0.1 wt% aqueous solution (liquid) of the treating agent of the present invention.

Next, 5 kg of a partially hydrolyzed polyacrylamide having a hydrolysis rate of 25 mol% (molecular weight: 16 million)
By adding water to dissolve and adjust to 5 tons,
A 0.1 wt% aqueous solution (liquid) of a polyacrylamide partial hydrolyzate having a hydrolysis rate of 25 mol% was prepared. Also,
Water was added to 5 kg of sodium carbonate to dissolve it, and the solution was adjusted to 5 tons to prepare a 0.1 wt% aqueous solution (liquid) of sodium carbonate.

A 0.1 wt% aqueous solution (liquid) of the treating agent of the present invention prepared as described above, a 0.1 wt% aqueous solution of a polyacrylamide partial hydrolyzate and a 0.1 wt% aqueous solution of sodium carbonate [liquid] + Liquid (used together)], or a 0.1% by weight aqueous solution of polyacrylamide partial hydrolyzate alone (liquid), 1 in front of the thickener for crushed stone washing water
Addition of 1, 2, 3, 4 to each of the 5 wastewater lines
Alternatively, it was added so as to be 5 ppm. However, in the liquid, the ratio of the polyacrylamide partial hydrolyzate aqueous solution and the sodium carbonate aqueous solution was set to 8: 2 (weight ratio), and the total weight of the polyacrylamide partial hydrolyzate and sodium carbonate was used to calculate the above. The polyacrylamide partial hydrolyzate aqueous solution and the sodium carbonate aqueous solution were simultaneously added so that the addition amount of

The above liquid, liquid + liquid, or liquid was added in front of the thickener at a place where the flow velocity was high in the waste water line, and the mixture was stirred. After stirring for 0.5 to 1 hour, the state of the supernatant of the waste water is observed, and the supernatant of each crushed stone washing water is collected, and the transparency and the suspended solids (SS) of the supernatant are collected.
Was measured. Fluoroscopy is by fluoroscopy, SS is JIS
(Wastewater analysis).

(Test Results) The results of measuring the transparency and SS are shown in FIGS. 1 and 2. FIG. 1 is a diagram showing the relationship between the transparency and the amount of each processing agent added, and FIG. 2 is a diagram showing the relationship between the SS and the amount of each processing agent added. 1 and 2, a
Shows the result of liquid, b shows the result of combined use of liquid + liquid, and c shows the result of liquid. From FIGS. 1 and 2, after the crushed stone washing water after being treated with the treatment agent aqueous solution (liquid) of the present invention is treated by using the polyacrylamide partial hydrolyzate aqueous solution and the sodium carbonate aqueous solution together (liquid + liquid). It is clear that both the transparency and SS are superior to the crushed stone washing water and the crushed stone washing water obtained by treating the crushed stone washing water and the aqueous solution of the partial hydrolyzate of polyacrylamide alone.

2. Tabletop test (crushed stone washing water) (Test method) Polyacrylamide partial hydrolyzate having a hydrolysis rate of 25 mol% (molecular weight: 16 million) and sodium carbonate in the mixing ratio of 9: 1, 8: 2, 7: 3, 6: 4,
5: 5, 4: 6, 3: 7 and 2: 8 (weight ratio) of the treatment agent of the present invention, and the above-mentioned compounding ratio of 1: 9 (weight ratio) treatment agent (comparative example), Hydrolysis rate 25 mol%
Partial polyacrylamide hydrolyzate (molecular weight: 160
The compounding ratio of 0,000) and potassium carbonate is 9: 1, 8: 2,
The treating agent of the present invention of 7: 3, 6: 4 and 5: 5 (weight ratio) was prepared by blending the polyacrylamide partial hydrolyzate and sodium carbonate or potassium carbonate in the above blending ratio using a blender (tabletop type). Prepared by mixing.

Each treating agent 1 prepared as described above
Water was added to and dissolved in 100 g to prepare 1000 ml, to prepare a 0.1 wt% aqueous solution of each treating agent. Mixing ratio (weight ratio) is 9: 1, 8: 2,
An aqueous solution of the treating agent of the present invention (a treating agent consisting of a polyacrylamide partial hydrolyzate and sodium carbonate or a polyacrylamide partial hydrolyzate and potassium carbonate) of 7: 3, 6: 4 or 5: 5, Crushed stone washing water 500m
Add 3 to each of the 10 beakers containing 1
It was added so as to be ppm.

As a comparative example, a 0.1% by weight aqueous solution of a treating agent (comparative example) in which the compounding ratio of the polyacrylamide partial hydrolyzate and sodium carbonate is 1: 9 (weight ratio),
A 0.1 wt% aqueous solution of polyacrylamide partial hydrolyzate (molecular weight: 16 million) having a hydrolysis rate of 25 mol% and a 0.1 wt% aqueous solution of sodium carbonate alone were used, and similarly, 500 ml of crushed stone washing water was added. It was added to each of the three beakers so that the added amount was 3 ppm. After the addition, stir at 120 rpm for 1 minute, then 60r
Stir at pm for 1 minute, collect the formed flocs,
The diameter of the flock was measured. In addition, after stirring for 1 minute and leaving still, the supernatant was collected and the turbidity of the supernatant was measured.
Flock diameter was measured by a ruler and turbidity was measured by a spectrophotometer.

(Test Results) The measurement results of the floc diameter and turbidity are shown in Table 1 and FIG. Table 1 shows the measured values of the diameter of flocs formed and the turbidity of the supernatant after the treatment with each treatment agent. FIG. 3 is a diagram showing the relationship between the blending ratio (polymerization ratio) of the partially hydrolyzed polyacrylamide and sodium carbonate and the turbidity. In Table 1 and FIG. 3, A indicates a polyacrylamide partial hydrolyzate having a hydrolysis rate of 25 mol% (molecular weight: 16 million), B indicates sodium carbonate, and C indicates potassium carbonate.

[0032]

[Table 1]

From Table 1, the crushed stone washing water after treated with the treating agent of the present invention is the crushed stone washing water after treated with the polyacrylamide partial hydrolyzate alone in all the blending ratios used in the test. In comparison, the diameter of the flocs formed is about the same, but it is clear that the turbidity of the supernatant is excellent.

Further, from FIG. 3, when the compounding ratio (polymerization ratio) of the polyacrylamide partial hydrolyzate and sodium carbonate is in the range of 9: 1 to 3: 7, and the polyacrylamide partial hydrolyzate is used alone [poly The mixing ratio (polymerization ratio) of acrylamide partial hydrolyzate and sodium carbonate is 10:
It is clear that the turbidity after treatment is superior to that of [0].

3. Desktop test (dust collection water) (Test method) Polyacrylamide (Molecular weight: 1000)
10%) and sodium carbonate in a mixing ratio (weight ratio) of 9: 1 to prepare a 0.1% by weight aqueous solution of the treating agent of the present invention.

As a comparative example, a 0.1% by weight aqueous solution of polyacrylamide (molecular weight: 10,000,000) alone, or a mixture of polyacrylamide (molecular weight: 10,000,000) and anhydrous sodium sulfate in a ratio of 9: 1 (weight ratio) was used. A 0.1 wt% aqueous solution of the mixture mixed in 1. was used.

500 m of blast furnace dust collecting water (I) and (II)
1 was taken and placed in 13 beakers each. To each beaker, the treating agent aqueous solution, the polyacrylamide aqueous solution, or the mixed aqueous solution of polyacrylamide and sodium sulfate of 0.2, 0.3, 0.4, or 0.5, respectively, is placed.
It was added so as to be ppm. After the addition, each was stirred with a jar tester at 60 rpm for 30 minutes to form flocs. The formed flock was sampled, the state of the flock was observed, and the diameter of the flock was measured by a ruler. In addition, after stirring, the mixture was allowed to stand for 5 minutes, and after standing, each supernatant was collected, the appearance of the supernatant was observed, and the transparency was measured by a fluorometer. Further, even when the treating agent was not added, the same operation was carried out to observe the state of flocs and the appearance of the supernatant, and the diameter of the flocs and the transparency of the supernatant were measured.

Table 2 shows the water quality of the blast furnace dust collecting water (I) and (II) used.

[0039]

[Table 2]

(Test Results) Tables 3 and 4 show the results of observation of the state of the formed flocs and the appearance of the supernatant, and the measurement results of the diameter of the formed flocs and the transparency of the supernatant.
In addition, the treated dust collecting water was judged based on the following judgment criteria, and the results are also shown in Tables 3 and 4.

In Tables 3 and 4, A is polyacrylamide (molecular weight: 10 million), B is sodium carbonate, and C.
Indicates an anhydrous salt of sodium sulfate. In the judgments of Tables 3 and 4, ◎ indicates that flock is formed, the supernatant is not turbid (transparency: 30 cm), and ○ indicates that flock is formed.
The state that the supernatant is a little cloudy (transparency: 20-30c
m) and △ are flocked and the supernatant is turbid (transparency: 10 to 20 cm), and x is small flocs and the supernatant is turbid (transparency is 10 cm or less). Show.

Further, in the floc states of Tables 3 and 4, the good condition has a tight flock and the supernatant liquid is transparent, and the good condition has a slightly poor floc property and the supernatant liquid is a little cloudy. The state in which the flocs are good is a state in which the flocs are not tight, and the supernatant is cloudy, and the state in which the flocs are not formed is a state in which no flocs are formed.

[0043]

[Table 3]

[0044]

[Table 4]

From Tables 3 and 4, the dust collecting water treated with the treating agent of the present invention was compared with the dust collecting water treated with polyacrylamide alone or with the mixture of polyacrylamide and anhydrous sodium sulfate. Although the diameters of the flocs formed are almost the same, it is clear that the flocs are excellent in appearance, appearance of the supernatant and transparency of the supernatant.

[0046]

Since the treating agent of the present invention is excellent in aggregating ability, the treating agent of the present invention can strongly agglomerate to form a floc with good tightness, and the spring phenomenon caused by the force of water. Can be suppressed. Further, the treatment agent of the present invention can suppress the generation of calcium carbonate scale due to the increase in pH of waste water after treatment. Therefore, the wastewater containing the inorganic fine particles treated with the treating agent of the present invention can suppress the phenomenon of flock of flocs caused by the force of water, and thus has excellent transparency, and the pH of the wastewater after the treatment is excellent.
Since the generation of calcium carbonate scale due to the rise can be suppressed, it can be reused favorably.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between a transparency and an amount of a processing agent added.

FIG. 2 is a diagram showing the relationship between SS and the amount of processing agent added.

FIG. 3 is a diagram showing the relationship between the mixing ratio (weight ratio) of the treatment agent of the present invention and turbidity.

[Explanation of symbols]

a aqueous solution of the treating agent of the present invention b combined use of an aqueous solution of a partial polyacrylamide hydrolyzate and an aqueous solution of sodium carbonate c a single aqueous solution of a polyacrylamide partial hydrolyzate A a polyacrylamide partial hydrolyzate B sodium carbonate C potassium carbonate

Claims (8)

[Claims] 1. A treatment agent for wastewater containing inorganic fine particles, which comprises a polyacrylamide polymer flocculant and an alkali metal carbonate. 2. A polyacrylamide polymer flocculant,
Polyacrylamide, acrylamide partial hydrolyzate having a hydrolysis rate of 40 mol% or less, copolymer of acrylamide and sodium acrylate, copolymer of acrylamide, sodium acrylate and sodium 2-acryloylamino-2-methylpropanesulfonate, Or those two
The treating agent according to claim 1, which is a mixture of two or more kinds. 3. A polyacrylamide partially hydrolyzed product having a molecular weight of 5,000,000 to 10,000,000 and a hydrolysis rate of 40 mol% or less has a molecular weight of 10,000,000 to 220.
The treating agent according to claim 2, wherein the copolymer of polyacrylamide and sodium acrylate has a molecular weight of 8,000,000 to 22,000,000, and the copolymer of acrylamide, sodium acrylate and AMPS has a molecular weight of 8,000,000 to 20,000,000. . 4. The alkali metal carbonate is sodium carbonate, potassium carbonate, or a mixture thereof.
The processing agent according to any one of 1 to 3. 5. The treatment agent according to claim 1, wherein the compounding ratio of the polyacrylamide polymer flocculant and the alkali metal carbonate is 19: 1 to 2: 8 (weight ratio). . 6. A method for treating wastewater containing inorganic fine particles, which comprises adding an aqueous solution of a treatment agent comprising a polyacrylamide polymer flocculant and an alkali metal carbonate to a wastewater line containing inorganic fine particles. 7. The concentration of an aqueous solution of a treatment agent composed of a polyacrylamide polymer flocculant and an alkali metal carbonate is
The processing method according to claim 6, which is 0.1 to 2% by weight. 8. The method according to claim 6 or 7, wherein the amount of the polyacrylamide-based polymer flocculant added to the wastewater line containing inorganic fine particles and the treatment agent consisting of an alkali metal carbonate is 0.1 to 30 ppm. Processing method.