1. The flocculant for treating the extracellular polysaccharide sewage is characterized by comprising 7-10 parts of extracellular polysaccharide, 3-4 parts of cellulose, 3-4 parts of sepiolite, 1-2 parts of activated carbon, 4-5 parts of astragalus membranaceus rubber powder and 6-8 parts of silk fibroin powder in parts by weight.

2. The flocculant of claim 1, wherein the exopolysaccharide is produced by fermentation of Bacillus licheniformis.

3. The exopolysaccharide sewage treatment flocculant of claim 2, wherein the fermentation reaction medium comprises: 60-70 g/L of sucrose; 3-6 g/L of monopotassium phosphate; 0.01-0.05 g/L of manganese sulfate; magnesium sulfate is 0.5-1.0 g/L; 0.03-0.07 g/L of ferric nitrate; 0.2-0.5 g/L of calcium chloride; 10-13 g/L of yeast powder; 15-18 g/L of peptone.

4. An exopolysaccharide sewage treatment flocculant according to claim 3, wherein the exopolysaccharide is prepared by fermentation and fermentation reaction of Bacillus licheniformis by placing the Bacillus licheniformis in a fermentation reaction medium at 32-35 ℃, shaking and culturing at 160-200 rpm for 4-5 days, and centrifuging to obtain a fermentation supernatant; dialyzing the fermented supernatant, and centrifuging to obtain dialyzed supernatant; and filtering the dialyzed supernatant, and performing vacuum freeze drying to obtain the exopolysaccharide.

5. An exopolysaccharide sewage treatment flocculant according to claim 1, wherein the silk fibroin powder preparation method comprises:

soaking silk in Na₂CO₃Degumming the obtained boiling water solution, then washing with deionized water and drying to obtain silk fibroin;

immersing silk fibroin fiber in CaCl₂Dissolving an ethanol-water ternary solution for 6 hours at the temperature of 60-70 ℃, filtering the obtained liquid, putting the filtered liquid into a dialysis bag, dialyzing the liquid in deionized water for 3 days, changing water every 8-12 hours, and concentrating to obtain a fibroin concentrated solution with the concentration of 50-100 g/L; the CaCl is₂CaCl in ternary ethanol-water solution₂The mass ratio of the ethanol to the water is 1: 2: 8;

spreading and freezing the fibroin concentrated solution, then carrying out vacuum freeze drying, and grinding to obtain the fibroin powder.

6. The method for preparing silk fibroin powder of claim 5, wherein the dialysis bag has a molecular weight cut-off of 6000-10000.

7. The method of preparing the silk fibroin powder of claim 5, wherein Na is present in the boiling aqueous solution₂CO₃The concentration is 0.015-0.02 mol/L, and the silk is soaked in Na₂CO₃The degumming is repeated for three times by the boiling water solution, and each time lasts for 25-30 min.

8. The preparation method of the exopolysaccharide sewage treatment flocculant according to claim 1, wherein exopolysaccharide, cellulose, sepiolite, activated carbon, astragalus membranaceus glue powder and silk fibroin powder are ground and sieved respectively and then uniformly mixed to prepare the exopolysaccharide sewage treatment flocculant.

9. The method for preparing exopolysaccharide sewage treatment flocculant according to claim 8, wherein the screening is 200 mesh.

Background

The water resource plays an important role in the production and life of human beings, is an indispensable natural resource in the whole biological world, and has important significance in the development of sewage treatment technology because the water pollution becomes more serious along with the development of industrialization and the health development of human beings and other ecological environments is seriously threatened. The flocculation method is a widely applied and common method in sewage treatment, and mainly adopts a sewage treatment technology that a certain flocculating agent is added into sewage to form floccules in the sewage, and then the floccules are removed by settling and other methods. The flocculating agent used in the flocculation method has many varieties and can be mainly divided into three categories of organic synthetic flocculating agent, inorganic flocculating agent and biological flocculating agent. The inorganic flocculation mainly comprises iron salts and aluminum salts, which have the advantages of low price, good flocculation effect and the like, but the using amount is large, the risk problems of poisoning, disease treatment, device corrosion and the like caused by long-term use of treated water exist, so the use has certain limitation, the organic synthetic high-molecular flocculant is difficult to degrade, serious environmental problems are easily caused, and cells are easily cancerated and the like after the monomers of the organic high-molecular compounds enter a human body, which are not beneficial to the health of human beings and life bodies. A bioflocculant is a special high-molecular metabolite which is produced by microorganisms and can coagulate and precipitate solid suspended particles which are not easy to degrade in liquid. The flocculant has the advantages of good biocompatibility, biodegradability, no toxicity, no secondary pollution and the like, and has great treatment potential on sewage and wastewater. In view of the above, the invention aims to prepare a sewage treatment flocculant which is efficient, nontoxic, free of secondary pollution, wide in application range and good in flocculation effect on the basis of microbial polymer metabolites and other natural harmless materials.

Disclosure of Invention

The invention aims to provide an extracellular polysaccharide sewage treatment flocculant and a preparation method thereof.

In order to achieve the purpose, the invention provides an exopolysaccharide sewage treatment flocculant and a preparation method thereof, wherein the exopolysaccharide sewage treatment flocculant comprises 7-10 parts by weight of exopolysaccharide, 3-4 parts by weight of cellulose, 3-4 parts by weight of sepiolite, 1-2 parts by weight of activated carbon, 4-5 parts by weight of astragalus membranaceus rubber powder and 6-8 parts by weight of silk fibroin powder.

Further, in the above technical scheme, the exopolysaccharide is prepared by fermentation reaction of bacillus licheniformis.

Further, in the above technical solution, the fermentation reaction medium includes: 60-70 g/L of sucrose; 3-6 g/L of monopotassium phosphate; 0.01-0.05 g/L of manganese sulfate; magnesium sulfate is 0.5-1.0 g/L; 0.03-0.07 g/L of ferric nitrate; 0.2-0.5 g/L of calcium chloride; 10-13 g/L of yeast powder; 15-18 g/L of peptone.

Further, in the technical scheme, the method for preparing the exopolysaccharide through fermentation and fermentation reaction of the bacillus licheniformis comprises the steps of placing the bacillus licheniformis in a fermentation reaction culture medium for 32-35 ℃, carrying out shake culture at 160-200 rpm for 4-5 days, and centrifuging to obtain a fermentation supernatant; dialyzing the fermented supernatant, and centrifuging to obtain dialyzed supernatant; and filtering the dialyzed supernatant, and performing vacuum freeze drying to obtain the exopolysaccharide.

Further, in the above technical scheme, the preparation method of the silk fibroin powder comprises:

soaking silk in Na₂CO₃Degumming the obtained boiling water solution, then washing with deionized water and drying to obtain silk fibroin;

immersing silk fibroin fiber in CaCl₂Dissolving an ethanol-water ternary solution for 6 hours at the temperature of 60-70 ℃, filtering the obtained liquid, putting the filtered liquid into a dialysis bag, dialyzing the liquid in deionized water for 3 days, changing water every 8-12 hours, and concentrating to obtain a fibroin concentrated solution with the concentration of 50-100 g/L; the CaCl is₂CaCl in ternary ethanol-water solution₂The mass ratio of the ethanol to the water is 1: 2: 8;

spreading and freezing the fibroin concentrated solution, then carrying out vacuum freeze drying, and grinding to obtain fibroin powder;

further, in the technical scheme, the interception relative molecular weight of the dialysis bag is 6000-10000.

Further, in the above technical scheme, Na in the boiling water solution₂CO₃The concentration is 0.015-0.02 mol/L, and the silk is soaked in Na₂CO₃The degumming is repeated for three times by the boiling water solution, and each time lasts for 25-30 min.

Further, in the above technical scheme, the preparation method of the extracellular polysaccharide sewage treatment flocculant is that extracellular polysaccharide, cellulose, sepiolite, activated carbon, astragalus glue powder and silk fibroin powder are respectively ground, sieved and uniformly mixed to prepare the extracellular polysaccharide sewage treatment flocculant.

Further, in the above technical scheme, the sieve is 200 meshes.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention provides an extracellular polysaccharide sewage treatment flocculant, which mainly takes microbial extracellular polysaccharide, cellulose, astragalus membranaceus gelatine powder, silk fibroin and some inorganic materials as main components, and the flocculant has a synergistic effect among the components to form outstanding sewage treatment performance, particularly has outstanding removal effect on suspended matters and heavy metals in sewage and is far better than the common sewage treatment flocculant; meanwhile, the removal rate of COD in the sewage is better.

2. The extracellular polysaccharide sewage treatment flocculant disclosed by the invention has the advantages that all main components are natural substances, the extracellular polysaccharide sewage treatment flocculant has good biodegradability, the material source is wide, the preparation is easy, the pollution is avoided, the use is convenient, the secondary pollution cannot be caused, the health and the safety are realized, and the environment protection is facilitated.

3. The flocculant comprises various different types of components of microbial exopolysaccharide, cellulose, silk fibroin, activated carbon, astragalus membranaceus glue powder and sepiolite, has rich flocculation action forms on pollutants in sewage, is suitable for treating various pollutants, and has wide applicable condition range.

Detailed Description

The following detailed description of specific embodiments of the invention is provided, but it should be understood that the scope of the invention is not limited to the specific embodiments.

Example 1

1. Microbial exopolysaccharide preparation

(1) Fermentation reaction culture medium:

65g/L of sucrose; 5g/L potassium dihydrogen phosphate; 0.03g/L of manganese sulfate; magnesium sulfate 0.8 g/L; 0.05g/L of ferric nitrate; 0.3g/L of calcium chloride; 10g/L of yeast powder; peptone 18 g/L; and (4) distilled water.

(2) Preparation of extracellular polysaccharide by fermentation

Preparing a culture medium according to the formula proportion of a fermentation reaction culture medium, then carrying out sterilization treatment at 120 ℃ for 15min to obtain the fermentation reaction culture medium, inoculating bacillus licheniformis into the fermentation reaction culture medium, wherein the inoculation amount is 5%, carrying out shaking culture at 33 ℃ and 160rpm for 5 days, and centrifuging to obtain a fermentation supernatant; dialyzing the fermented supernatant, and centrifuging to obtain dialyzed supernatant; and filtering the dialyzed supernatant, and performing vacuum freeze drying to obtain the exopolysaccharide.

2. Preparation of silk fibroin powder:

(1) soaking silk in Na₂CO₃Degumming the obtained boiling water solution, washing with deionized water for 5 times, and drying at 70 deg.C for 10 hr to obtain silk fibroin fiber; in boiling aqueous solution of Na₂CO₃The concentration is 0.02mol/L, and the silk is soaked in Na₂CO₃The degumming is repeated three times for 30min each time.

(2) Immersing silk fibroin fiber in CaCl₂Dissolving the ethanol-water ternary solution for 6 hours at 70 ℃, filtering the obtained liquid, putting the filtered liquid into a dialysis bag, dialyzing the liquid in deionized water for 3 days, changing water every 12 hours, and concentrating to obtain fibroin concentrated solution with the concentration of 90 g/L; the CaCl is₂CaCl in ternary ethanol-water solution₂The mass ratio of the ethanol to the water is 1: 2: 8; the interception relative molecular weight of the dialysis bag is 6000-10000.

(3) Spreading the fibroin concentrated solution in a glass culture dish, freezing at-5 deg.C for about 2 hr, freeze drying at-60 deg.C for 36 hr in a vacuum freeze dryer, and grinding to obtain fibroin powder.

3. Preparation of extracellular polysaccharide sewage treatment flocculant

(1) The flocculant component:

9 parts of exopolysaccharide, 4 parts of cellulose, 3 parts of sepiolite, 2 parts of activated carbon, 4 parts of astragalus membranaceus gelatine powder and 8 parts of silk fibroin powder.

(2) Preparation of flocculant sample 1-1: the components are respectively weighed according to the mass portion ratio, and the exopolysaccharide, the cellulose, the sepiolite, the activated carbon, the astragalus membranaceus glue powder and the silk fibroin powder are respectively ground and sieved by a 200-mesh sieve, and then are uniformly stirred and mixed to prepare the exopolysaccharide sewage treatment flocculant.

(3) Preparation of comparative sample 1-1: the preparation method is basically the same as that of the flocculant sample 1-1, except that no tragacanth powder is added.

(4) Comparative samples 1 to 2: the common sewage treatment flocculating agent is purchased in the market.

4. Comparison of wastewater treatment effects

Treating the industrial sewage sample by using the sewage treatment flocculating agent of the sample 1-1 and the comparative example 1-1; adding a flocculating agent into each group, stirring until flocs are formed, standing for 2.5 hours, taking supernatant, detecting suspended matters, heavy metal ions and COD in the supernatant, and respectively calculating the removal rate of the suspended matters, the removal rate of the heavy metals and the removal rate of the COD by taking an untreated sewage sample as a control, wherein the results are shown in Table 1; as can be seen from Table 1, the flocculant of the invention has a removal rate of more than 90% for industrial sewage suspended matters, and a removal rate of 99.3% for heavy metals in sewage, and a removal rate of COD is also more than 80%, which is far better than that of a comparison group.

TABLE 1 effect of flocculant on treating industrial sewage

Example 2

1. Microbial exopolysaccharide preparation

(1) Fermentation reaction culture medium:

60g/L of sucrose; 3g/L of monopotassium phosphate; 0.01g/L of manganese sulfate; magnesium sulfate 0.5 g/L; 0.07g/L of ferric nitrate; 0.5g/L of calcium chloride; 10g/L of yeast powder; peptone 18 g/L; and (4) distilled water.

(2) Preparation of extracellular polysaccharide by fermentation

Preparing a culture medium according to the formula proportion of a fermentation reaction culture medium, then carrying out sterilization treatment at 120 ℃ for 15min to obtain the fermentation reaction culture medium, inoculating bacillus licheniformis into the fermentation reaction culture medium, wherein the inoculation amount is 5%, carrying out shaking culture at 32 ℃, 200rpm for 5 days, and centrifuging to obtain a fermentation supernatant; dialyzing the fermented supernatant, and centrifuging to obtain dialyzed supernatant; and filtering the dialyzed supernatant, and performing vacuum freeze drying to obtain the exopolysaccharide.

2. Preparation of silk fibroin powder:

(1) soaking silk in Na₂CO₃Degumming the obtained boiling water solution, washing with deionized water for 3 times, and drying at 60 deg.C for 12 hr to obtain silk fibroin fiber; in boiling aqueous solution of Na₂CO₃The concentration is 0.015mol/L, the silk is soaked in Na₂CO₃The degumming is repeated three times for 30min each time.

(2) Immersing silk fibroin fiber in CaCl₂Dissolving an ethanol-water ternary solution for 6 hours at the temperature of 60 ℃, filtering the obtained liquid, putting the filtered liquid into a dialysis bag, dialyzing the liquid in deionized water for 3 days, changing water every 8 hours, and concentrating to obtain a fibroin concentrated solution with the concentration of 50 g/L; the CaCl is₂CaCl in ternary ethanol-water solution₂The mass ratio of the ethanol to the water is 1: 2: 8; the interception relative molecular weight of the dialysis bag is 6000-10000.

(3) Spreading the fibroin concentrated solution in a glass culture dish, freezing at-5 deg.C for about 2 hr, freeze drying at-60 deg.C for 36 hr in a vacuum freeze dryer, and grinding to obtain fibroin powder.

3. Preparation of extracellular polysaccharide sewage treatment flocculant

(1) The flocculant component:

10 parts of exopolysaccharide, 4 parts of cellulose, 4 parts of sepiolite, 2 parts of activated carbon, 5 parts of astragalus membranaceus rubber powder and 8 parts of silk fibroin powder.

(2) Preparation of flocculant sample 2-1: the components are respectively weighed according to the mass portion ratio, and the exopolysaccharide, the cellulose, the sepiolite, the activated carbon, the astragalus membranaceus glue powder and the silk fibroin powder are respectively ground and sieved by a 200-mesh sieve, and then are uniformly stirred and mixed to prepare the exopolysaccharide sewage treatment flocculant.

(3) Preparation of comparative sample 2-1: the preparation method is basically the same as that of the flocculant sample 2-1, except that no astragalus membranaceus glue powder is added.

4. Comparison of wastewater treatment effects

Treating the industrial sewage sample by using the sewage treatment flocculating agent of the sample 2-1 and the comparative example 2-1; adding a flocculating agent into each group, stirring until flocs are formed, standing for 2.5 hours, taking supernatant, detecting suspended matters, heavy metal ions and COD in the supernatant, and respectively calculating the removal rate of the suspended matters, the removal rate of the heavy metals and the removal rate of the COD by taking an untreated sewage sample as a reference, wherein the results are shown in Table 2; as can be seen from Table 2, the flocculant of the invention has a removal rate of more than 90% for industrial sewage suspended matters, a removal rate of more than 99.1% for heavy metals in sewage, a removal rate of COD (chemical oxygen demand) of more than 80%, and a sewage treatment effect far better than that of a comparison group.

TABLE 2 effect of flocculant on treating industrial sewage

Example 3

1. Microbial exopolysaccharide preparation

(1) Fermentation reaction culture medium:

70g/L of sucrose; 6g/L potassium dihydrogen phosphate; 0.05g/L of manganese sulfate; magnesium sulfate 1.0 g/L; 0.03g/L of ferric nitrate; 0.2g/L of calcium chloride; yeast powder 13 g/L; peptone 15 g/L; and (4) distilled water.

(2) Preparation of extracellular polysaccharide by fermentation

Preparing a culture medium according to the formula proportion of a fermentation reaction culture medium, then carrying out sterilization treatment at 120 ℃ for 15min to obtain the fermentation reaction culture medium, inoculating bacillus licheniformis into the fermentation reaction culture medium, wherein the inoculation amount is 5%, carrying out shaking culture at 35 ℃ and 160rpm for 4 days, and centrifuging to obtain a fermentation supernatant; dialyzing the fermented supernatant, and centrifuging to obtain dialyzed supernatant; and filtering the dialyzed supernatant, and performing vacuum freeze drying to obtain the exopolysaccharide.

2. Preparation of silk fibroin powder:

(1) soaking silk in Na₂CO₃Degumming the obtained boiling water solution, washing with deionized water for 6 times, and drying at 70 deg.C for 11 hr to obtain the final productSilk fibroin fiber; in boiling aqueous solution of Na₂CO₃The concentration is 0.02mol/L, and the silk is soaked in Na₂CO₃The degumming is repeated three times for 25min each time.

(2) Immersing silk fibroin fiber in CaCl₂Dissolving an ethanol-water ternary solution for 6 hours at the temperature of 60 ℃, filtering the obtained liquid, putting the filtered liquid into a dialysis bag, dialyzing the liquid in deionized water for 3 days, changing water every 12 hours in the dialysis bag, and concentrating to obtain a fibroin concentrated solution with the concentration of 100 g/L; the CaCl is₂CaCl in ternary ethanol-water solution₂The mass ratio of the ethanol to the water is 1: 2: 8; the interception relative molecular weight of the dialysis bag is 6000-10000.

(3) Spreading the fibroin concentrated solution in a glass culture dish, freezing at-5 deg.C for about 2 hr, freeze drying at-60 deg.C for 36 hr in a vacuum freeze dryer, and grinding to obtain fibroin powder.

3. Preparation of extracellular polysaccharide sewage treatment flocculant

(1) The flocculant component:

7 parts of exopolysaccharide, 3 parts of cellulose, 3 parts of sepiolite, 1 part of activated carbon, 5 parts of astragalus membranaceus rubber powder and 6 parts of silk fibroin powder.

(2) Preparation of flocculant sample 3-1: the components are respectively weighed according to the mass portion ratio, and the exopolysaccharide, the cellulose, the sepiolite, the activated carbon, the astragalus membranaceus glue powder and the silk fibroin powder are respectively ground and sieved by a 200-mesh sieve, and then are uniformly stirred and mixed to prepare the exopolysaccharide sewage treatment flocculant.

(3) Preparation of comparative sample 3-1: the preparation method is basically the same as that of the flocculant sample 3-1, except that no astragalus membranaceus glue powder is added.

4. Comparison of wastewater treatment effects

Treating the industrial sewage sample by using the sewage treatment flocculating agent of the sample 3-1 and the comparative example 3-1; adding a flocculating agent into each group, stirring until flocs are formed, standing for 2 hours, taking supernatant, detecting suspended matters, heavy metal ions and COD in the supernatant, and respectively calculating the removal rate of the suspended matters, the removal rate of the heavy metals and the removal rate of the COD by taking an untreated sewage sample as a control, wherein the results are shown in a table 3; as can be seen from Table 3, the flocculant of the invention has a removal rate of more than 90% for industrial sewage suspended matters, and a removal rate of more than 99.5% for heavy metals in sewage, and a removal rate of COD is also more than 80%, which is much better than that of the comparative group.

TABLE 3 effect of flocculating agent on treating industrial sewage

Example 4

1. Microbial exopolysaccharide preparation

(1) Fermentation reaction culture medium:

67g/L of sucrose; 5g/L potassium dihydrogen phosphate; 0.02g/L of manganese sulfate; 0.6.0g/L magnesium sulfate; 0.04g/L of ferric nitrate; 0.4g/L of calcium chloride; yeast powder 12 g/L; peptone 16 g/L; and (4) distilled water.

(2) Preparation of extracellular polysaccharide by fermentation

Preparing a culture medium according to the formula proportion of a fermentation reaction culture medium, then carrying out sterilization treatment at 120 ℃ for 15min to obtain the fermentation reaction culture medium, inoculating bacillus licheniformis into the fermentation reaction culture medium, wherein the inoculation amount is 5%, carrying out shaking culture at 35 ℃, 200rpm for 4 days, and centrifuging to obtain a fermentation supernatant; dialyzing the fermented supernatant, and centrifuging to obtain dialyzed supernatant; and filtering the dialyzed supernatant, and performing vacuum freeze drying to obtain the exopolysaccharide.

2. Preparation of silk fibroin powder:

(1) soaking silk in Na₂CO₃Degumming the obtained boiling water solution, washing with deionized water for 6 times, and drying at 60 deg.C for 12 hr to obtain silk fibroin fiber; in boiling aqueous solution of Na₂CO₃The concentration is 0.015mol/L, the silk is soaked in Na₂CO₃The degumming is repeated three times for 25min each time.

(2) Immersing silk fibroin fiber in CaCl₂Dissolving an ethanol-water ternary solution for 6 hours at the temperature of 60 ℃, filtering the obtained liquid, putting the filtered liquid into a dialysis bag, dialyzing the liquid in deionized water for 3 days, changing water every 9 hours, and concentrating to obtain a fibroin concentrated solution with the concentration of 75 g/L; the CaCl is₂CaCl in ternary ethanol-water solution₂The mass ratio of the ethanol to the water is 1: 2: 8; the interception relative molecular weight of the dialysis bag is 6000-10000.

(3) Spreading the fibroin concentrated solution in a glass culture dish, freezing at-5 deg.C for about 2 hr, freeze drying at-60 deg.C for 36 hr in a vacuum freeze dryer, and grinding to obtain fibroin powder.

3. Preparation of extracellular polysaccharide sewage treatment flocculant

(1) The flocculant component:

9 parts of exopolysaccharide, 39 parts of cellulose, 39 parts of sepiolite, 2 parts of activated carbon, 4-5 parts of astragalus membranaceus rubber powder and 7 parts of silk fibroin powder.

(2) Preparation of flocculant sample 4-1: the components are respectively weighed according to the mass portion ratio, and the exopolysaccharide, the cellulose, the sepiolite, the activated carbon, the astragalus membranaceus glue powder and the silk fibroin powder are respectively ground and sieved by a 200-mesh sieve, and then are uniformly stirred and mixed to prepare the exopolysaccharide sewage treatment flocculant.

(3) Preparation of comparative sample 4-1: the preparation method is basically the same as that of the flocculant sample 4-1, except that no astragalus membranaceus rubber powder is added.

(4) Comparative sample 4-2: only the astragalus membranaceus glue powder is used as a flocculating agent.

4. Comparison of wastewater treatment effects

Treating the industrial sewage sample by using the sewage treatment flocculating agent of the sample 4-1 and the comparative example 4-1; adding a flocculating agent into each group, stirring until flocs are formed, standing for 2.5 hours, taking supernatant, detecting suspended matters, heavy metal ions and COD in the supernatant, and respectively calculating the removal rate of the suspended matters, the removal rate of the heavy metals and the removal rate of the COD by taking an untreated sewage sample as a reference, wherein the results are shown in a table 4; as can be seen from Table 4, the flocculant of the invention has a removal rate of more than 90% for industrial sewage suspended matters, a removal rate of 98.9% for heavy metals in sewage, and a removal rate of COD (chemical oxygen demand) of more than 80%, which are far better than those of the comparative group.

TABLE 4 effect of flocculant on treating industrial sewage

In conclusion, the extracellular polysaccharide sewage treatment flocculant has high removal rate on industrial sewage suspended matters, heavy metals and COD (chemical oxygen demand), has outstanding and stable sewage treatment effect, mainly takes natural substances as main components, has no toxicity or secondary pollution, forms stable flocculate, is not easy to influence the flocculation effect due to too fast stirring, and has simple preparation method and easy production.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.