JPH02194803A - Flocculant - Google Patents

Abstract

PURPOSE:To prepare a flocculant having superior fluocculating capacity particularly to organic turbid sewage by mixing an aluminum salt flocculant and a secondary amine - epichlorhydrin cation high molecular polymer. CONSTITUTION:An inorganic aluminum salt flocculant and an organic secondary amine - epichlorhydrin cation high molecular copolymer are mixed to prepare a one-part type flocculant. As for the aluminum salt flocculant, for example, polyaluminum chloride, aluminum sulfate or the like is used. As for a secondary amine -epichlorhydrin cation high molecular polymer, for example, a polymer or the like prepared by means of polycondensation of amine such as dimethylamine and epichlorhydrin is used. Although said flocculant is one-part type, mixed solution is not only stable but also superior in flocculating performance compared with separate use. Also, treatment cost can be reduced and water can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a flocculant, and particularly to a flocculant that exhibits excellent flocculating ability for organic turbid wastewater.

(Prior Art) Polyaluminum chloride and aluminum sulfate have long been used as water treatment agents for clean water, sewage, industrial water, factory wastewater, etc.

However, polyaluminum chloride and aluminum sulfate are not commonly used in coagulation-sedimentation treatment of water with a lot of organic turbidity, such as water containing a lot of algae such as dams and lakes, or water containing a lot of humic substances. Compared to the treatment of inorganic suspended solids, it is assumed that the amount is 4 summers.

As a result, it is necessary to use a large amount of alkaline agent for neutralization, the amount of electrolyte in the treated water increases, the carryover of coagulated flocs is likely to occur, the turbidity of the treated water increases, or the filtration process in the subsequent stage increases. Filters tend to become clogged during processing.

As a solution to this problem, by using a combination of an inorganic flocculant such as polyaluminum chloride or aluminum sulfate and a polymer flocculant such as polyacrylamide or its partially hydrolyzed product, and performing flocculation treatment by adding these separately. , a method of forming strong flocs has been adopted.

However, using two types of flocculants in this way not only increases the size of the flocculation stirring device, but also requires a separate dilution tank and dissolution tank for the flocculant, which not only increases the size of the flocculation processing equipment but also complicates the operation. becomes.

Therefore, there is currently a demand for a flocculant that has excellent water treatment effects and can be treated using a simple treatment method.

(Issues to be Solved by the Invention) Under these circumstances, the present inventors have developed an inorganic flocculant and an organic flocculant as flocculants with excellent flocculation performance in order to solve the above-mentioned problems. The present invention was arrived at as a result of extensive research in order to obtain a flocculant having the following advantages.

(Means for Solving the Problems) That is, the present invention provides aluminum salt-based flocculants and secondary amines.
The present invention relates to a flocculant containing an epichlorohydrin-based cationic polymer.

(for production) The invention will be described in further detail below.

Examples of the aluminum salt-based flocculant used in the present invention include polyaluminum chloride, aluminum sulfate, aluminum chloride, and the like.

In addition, secondary amine-epichlorohydrin-based cationic polymers can be produced by polycondensation reaction of amines such as dimethylamine, methylethylamine, diethylamine, methylpropylamine, methylbutylamine, dibutylamine, etc. with epichlorohydrin. The resulting polymers or modified products thereof.

In the present invention, an -acid type flocculant is prepared by mixing such an aluminum salt type flocculant with a secondary amine-epichlorohydrin cationic polymer.

In general, when an inorganic flocculant and an organic flocculant are mixed, a reactant (precipitate) is generated, or even if no reactant is generated, the flocculating effect is lower than when both are used alone. , - not used in acid form.

However, even though the flocculant of the present invention is a one-component type, the mixed solution is not only stable over a long period of time, but also has superior flocculation performance than when each is used alone. This is a characteristic of flocculants.

Regarding the usage ratio of the aluminum salt-based flocculant and the secondary amine-epichlorohydrin-based cationic polymer, the solid content of the latter polymer is 0.25 to ^1203 of the former aluminum salt-based flocculant. ~4. They are mixed so that the weight ratio of Ot falls within the range of 0.5 to 3.0, more preferably 0.5 to 3.0.

That is, if it deviates from this range, the effective amounts of the two during the flocculation treatment will be unbalanced, resulting in a decrease in flocculating performance, making it impossible to obtain the flocculant with excellent flocculating properties of the present invention.

The mixing method may be normal mixing and stirring, and the order of addition may be in any order.

The unexploded +jJ flocculant may be used in the same manner as a normal flocculant, and there is no need to take any special measures when using it.

(Effects of the Invention) Although the flocculant of the present invention is in the -acid type, the mixed solution is not only stable over a long period of time, but also has better flocculation performance than each agent used alone.

Therefore, in the treatment of organic suspended solids, the treatment with the present flocculant forms stronger flocs than the treatment with conventional aluminum salt-based flocculants or the combined treatment with polyacrylamide-based polymer flocculants. Therefore, carryover to the treated water is prevented and high quality treated water can be obtained.

In addition, an excellent flocculating effect can be achieved with a small amount added, the amount of alkaline agent used for pH adjustment can be reduced, and the amount of electrolyte in the treated water is also reduced, resulting in a reduction in water treatment costs. It is suitable for reuse as water.

Furthermore, since the flocculant of the present invention contains an inorganic flocculant and an organic flocculant in a single-part type, flocculation treatment equipment can be simplified, and its effects as an unprecedented flocculant are extremely beneficial.

(Example) The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto.

In the Examples, all percentages are by weight unless otherwise specified.

Example 1 Polyaluminum chloride (^1e0310%, Taki Kagaku Toki trade name PAC250A) and secondary amine-ebichlorohydrin-based polymer (cy9notylamine-ehyrylorhibirin copolycondensate) , solid content concentration 50%, polyaluminum chloride All? The flocculant of the present invention was produced by mixing both of them so that the solid content of the high molecular weight polymer was in a weight ratio of 1.25 to the amount of s3.

A flocculation test was conducted under the following conditions using the flocculant of the present invention and the flocculant used in the mixing for comparison alone.

Dissolve humic acid (reagent manufactured by Wako Pure Chemical Industries, Ltd.) in tap water,
Test water with a chromaticity of 272 degrees and a pH of 7.14 was prepared.

500 ml of this sample water was placed in a 500 ml beaker, and each flocculant was added thereto in the proportions shown in Table 1 while rapidly stirring (120 rpm) using a jar tester.

After the addition of the flocculant, rapid stirring was performed for 2 minutes, then slow stirring (30 rpm) was performed for 10 minutes, and the mixture was allowed to stand for 10 minutes.

In addition, when two types of flocculants were used, the second flocculant was added one minute after the addition of the first flocculant, and the test was conducted in the same manner.

100 ml of the supernatant water was collected and the chromaticity was measured. Furthermore, the chromaticity of the supernatant water after passing through a filter paper (Toyo Roshi N005^) was also measured, and the results are shown in Table 1.

The chromaticity was measured by a colorimetric method at an absorption wavelength of 410 wμ.

Table 1 Note: PACn is an abbreviation for aluminum chloride. The amounts of PAC and polymer added are shown in tangible amounts.

・(First): Flocculant added first, (Later): Flocculant added second Regarding the chromaticity of the treated water in Table 1, there is a large difference in the chromaticity of the supernatant water and the filtrated water. indicates that the formed flocs are small and the flocs are difficult to settle, but when treated with the flocculant of the present invention, the difference in color between the supernatant water and the filtered water is small;
It can be seen that large flocs with good sedimentation properties are formed.

Example 2 Polyaluminum chloride (^1e0310%, Taki Chemical)
Product name: PAC250A) and secondary amine-ebichlorohydrin-based polymer (Ci9 methylamine-Epiku σ Ruhibirin copolycondensate, solids concentration 50%, Tamoto Chemical Co., Ltd. Product name: Taki7U Fuku) CL-650), the flocculant of the present invention was manufactured and its stability was investigated.

The solid content of the polymer was mixed at a weight ratio of 1.25 to the Ale03 content of the polyaluminum chloride, and the mixed solution was stored at 30°C for 3 months.

An agglutination test was conducted in the same manner as in Example 1 using this mixed storage solution and the newly prepared mixed solution.

The test water was prepared using humic acid in the same manner as in Example 1, and had a chromaticity of 384 degrees and a pH of 6.90.

The aggregation test results are shown in Table 2.

Table 2 Note) - The amount of coagulant added is shown in tangible amount.

As is clear from Table 2, the flocculant of the present invention shows no decline in flocculating performance even after three months of storage, and there is no change in appearance, viscosity, etc. during or after storage. I couldn't see it.

Example 3 Polyaluminum chloride (AI 20 dO%, trade name PAC250A manufactured by Tamoto Kagaku Co., Ltd.) and a secondary amine-epichlorohydrin-based high molecular weight polymer (silicon-epiglolhibirin copolycondensate) , solid content concentration 50%, Tabon Chemical ■
The coagulant of the present invention was prepared by mixing the two products using 9't7Utsuku CI, -650) so that the weight ratio of the solid content of the polymer to the At20° amount of polyaluminum chloride was 0.56. was manufactured.

A flocculation test was conducted under the following conditions using the flocculant of the present invention and the flocculant used in the mixing for comparison alone.

A flocculation test was conducted using pond water (a pond in Harima-cho, Kako-gun, Hyogo Prefecture) in which the algae eudrina and spirotinia mainly grew as test water. The turbidity of this pond water was 74 ppm, and the pH was 7.90.

500I1 of this sample water was placed in an 11-capacity 500I beaker, and each flocculant was added thereto in the proportions shown in Table 3 while rapidly stirring (120 rpm) using a jar tester.

After the addition of the flocculant, rapid stirring was performed for 3 minutes, then slow stirring (30 rpm) was performed for 10 minutes, and the mixture was allowed to stand for 10 minutes.

In addition, when two types of flocculants were used, the second flocculant was added one minute after the addition of the first flocculant, and the test was conducted in the same manner.

After standing still, 100 ml of the Tamazumi water was collected and its turbidity and pH were measured, and the results are shown in Table 3.

The supernatant water turbidity was measured using an integrating sphere turbidity W1.

Table 3 Example 4 Liquid aluminum sulfate (AI20s 8%, manufactured by Tamoto Kagaku) and secondary amine-epichlorohydrin polymer (synthetic acid-epichlorohydrin copolycondensate,
Liquid aluminum sulfate (Alc) was prepared using Tamoto Chemical Co., Ltd. (trade name: T-7U-TSUK CL-650) with a solid content concentration of 50%.
The flocculant of the present invention was produced by mixing both Chft and Chft so that the solid content of the high molecular weight polymer was at a weight ratio of 2.68.

Using the sample water used in Example 1, an agglomeration test was conducted in the same manner as in Example 1.

The results are shown in Table 4.

j Main)・PAC: aluminum chloride llll each・The amounts of PAC and polymer added are shown in tangible amounts.

Claims (1)

[Claims] A flocculant containing an aluminum salt-based flocculant and a secondary amine-epichlorohydrin-based cationic polymer.