CN102517233A - Microbial flocculant and its production method - Google Patents

Abstract

The invention provides a microbial flocculant and its production method, which comprises that: first, wastewater of a sewage treatment plant is utilized to screen out a strain with high flocculating ability, a preservation number of CGMCC5066, and a classified nomenclature of Geotrichum candidum, then the strain is put into a seed culture medium for culture so as to obtain a seed liquid, which is then inoculated into wastewater of a cake factory or distillery for fermentation so as to obtain a microbial fermentation liquid, and then the microbial fermentation liquid is subjected to post-treatment, so that a microbial flocculant can be obtained. With cake factory or distillery wastewater as the raw material, the microbial flocculant of the invention has greatly reduced production cost, and strong flocculation ability, as well as good effect in environment protection.

Description

A kind of microbial flocculant and working method thereof

Technical field

The present invention relates to a kind of microbial flocculant and utilize cake factory or the method for this microbial flocculant of distillery waste preparation.

Background technology

Microbial flocculant is a kind of novel water conditioner of representing the flocculation agent developing direction, and it is produced by the Institute of Micro-biology of special metabolic function, and its function shows as the removal of adsorbing, flocculate of suspended particle, gegenion etc. in the liquid system.The essence of microbial flocculant is biomacromolecule; Mainly contain protein-based, polyose, glycoprotein analog, proteoglycan and DNA class etc., but be one type of novel water conditioner that possesses characteristics such as nontoxic, safe in utilization, biodegradable large-scale industrial production.And the preparation of microbial flocculant belongs to the biotechnology that specific function biomacromolecule preparation is produced.

At present, a lot of countries are studied microbial flocculant, and nearly 80 kinds of the mikrobe of finding so far with flocculence comprises bacterium, mould, and yeast, actinomycetes and algae etc., and at flocculating conditions, flocculation mechanism; Flocculation agent separation and purification, character, application; Aspects such as the Gene Handling of produce flocculant have carried out a series of research.These have flocculation activity, are mostly screened from soil, mud, sewage by the mikrobe of people's concern.

Although that microbial flocculant has is nontoxic, non-secondary pollution and biodegradable characteristics, because its preparation utilizes sugar or agricultural byproducts as raw materials for production more, cost is higher, has restricted microbial flocculant suitability for industrialized production and large-scale application.Need set about from two aspects for reducing production costs: the one, actively seek cheap starting material, reduce production costs significantly, the 2nd, to the physico-chemical property and the purposes of biological flocculant, select rational industriallization extraction process and method of use.

Publication number is that the Chinese patent of CN101186366A openly provides a kind of method of utilizing sewage treatment plant residual active sludge to produce biological flocculant; At first starting material are carried out the pre-treatment preparation and purify mud; Then purification mud is carried out cytoclasis and prepare the extracting slurries; Carry out solid-liquid separation then and obtain bullion microbial flocculant solution respectively, then bullion microbial flocculant solution is carried out aftertreatment and obtain the microbial flocculant finished product.The shortcoming of this method is: complicated process of preparation, and the not mentioned flocculation agent activeconstituents that from active sludge, extracts, and preparation has certain blindness, and in addition, the flocculating rate of the microbial flocculant that this preparation method obtains is lower.

Chinese patent CN101327975B discloses the another kind of method for preparing microbial flocculant; It utilizes the source of Dell's Ford acidovorax facilis as the preparation microbial flocculant; The preparation of the preparation of the bullion of the preparation through substratum, the fermentation culture of bacterial classification, flocculation agent, the elaboration of flocculation agent obtains microbial flocculant, this method complex technical process at last; Preparing method's cost is higher, and the benefit of environment is not had embodiment.

In addition, disclose in " earth and environment " 2008 the 36th volumes 2 phases " screening of bacterium for producing flocculant and application " Geotrichum candidumThrowing out, but do not utilize waste water to carry out culture experiment.

Summary of the invention

Deficiency to the prior art existence; The present invention filters out the bacterial classification with efficient flocculating ability from sewage work; And start with from the starting material of producing microbial flocculant; Utilize cake factory or distillery waste to produce microbial flocculant, not only greatly reduce the production cost of microbial flocculant, also found an outlet simultaneously for the food service industry water reuse.

For achieving the above object, the invention provides following technical scheme:

At first; From sewage work, filter out a strain in the isolated multiple bacterial strain and can be used as the bacterial strain that microbial flocculant is produced bacterium; This bacterial strain is through China Committee for Culture Collection of Microorganisms common micro-organisms center (CGMCC) preservation, and the address is: No. 3 Institute of Microorganism, Academia Sinica in Yard 1, BeiChen xi Road, Chaoyang District, Beijing City, and preservation date is: on May 18th, 2011; Preserving number is: CGMCC 5066, the classification name: geotrichum candidum ( Geotrichum candidum).

Secondly, the present invention also provides a kind of method of utilizing the waste water production microbial flocculant of cake factory or brewery, and its concrete steps are:

1, the fermentation culture of bacterial classification:

(a), the screening flocculation agent is produced bacteria strain from the active sludge of sewage work;

(b), utilize the waste water of cake factory or brewery to prepare microbial flocculant, at first, with what filter out Geotrichum candidumBacterium is linked in the seed culture medium, under 30 ~ 37 ℃ of conditions, cultivates 18 ~ 36h, obtains seed liquor;

(c), then seed liquor is joined through the brewery of high pressure steam sterilization or the fermention medium of cake factory waste water by the inoculum size that accounts for wastewater volume 1 ~ 10%, and under 30 ~ 40 ℃ of conditions, carry out aerobic fermentation;

(d), during the fermentation, the rotating speed of shaking table is controlled at 60 ~ 200rpm, and adopts the alkaline solution of 1 ~ 5M to regulate the pH value in 5 ~ 8 scope;

(e), can obtain microbial fermentation solution behind fermentation 24 ~ 72h.

2, the preparation of microbial flocculant:

(a), the fermented liquid that obtains centrifugal 20-30min under the 6000-9000rpm condition is removed thalline; Liquid after the spinning is joined in 4 ℃ the ethanol that is equivalent to 3 times of volumes of fermented liquid; And at 4 ℃ of condition held 12h at least; It is thus clear that the flocculation sediment deposits yields, this flocculate precipitate is the flocculation agent raw product;

(b), centrifugal 30min separates ethanol with flocculate precipitate under the 4000rpm condition.Is that 60 ± 2 ℃, vacuum tightness are vacuum-drying 5-6h under the condition of 0.06MPa with the flocculate precipitate after centrifugal in temperature, can obtain the solid flocculation agent.

When described waste water is distillery waste, need before using 20～200 times of distillery waste dilutions are regulated pH value 5～7, high pressure steam sterilization with sodium hydroxide.And then seed liquor joined in this distillery waste by the inoculum size that accounts for wastewater volume 4 ~ 8%.

Aforesaid use distillery waste prepares the method for flocculation agent, and the flocculation agent that obtains partly adds the water with centrifuged supernatant equivalent with the solid flocculation agent earlier when using, and mixing is for use.In the waste water of need handling per ton, add 0-500g calcium chloride, the 2-50 that adds again behind the mixing rises microbial flocculant, with sodium hydroxide adjusting pH value 4.0-8.0, fully shakes up standing sedimentation behind the mixing.

When described waste water was cake factory waste water, it earlier transferred to 5-8 with sodium hydroxide solution with the pH value of cake factory waste water, high pressure steam sterilization, then with seed liquor by volume 1～10% inoculum size join in the fermention medium of cake factory waste water.

The flocculation agent that the waste water of use cake factory prepares, when using, with the water of solid part adding with centrifuged supernatant equivalent, mixing is for use earlier.

The flocculation agent that aforesaid method prepares, when using, the pH value of keeping environment for use is 4.0-8.0.

Aforesaid distillery waste, it includes organic acid, glucide and nitrogenous compound, and COD is about 100g/l, and it is acid that pH is, and needs 20～200 times of distillery waste dilutions before using, and promptly COD is 0.5g/l～5 g/l, regulates pH value 5～7 with sodium hydroxide.

Aforesaid cake factory waste water, nitrogenous compounds such as starch-containing in it, glucide and fat, COD is about 3g/L, can directly be used for doing fermention medium without dilution.

Geotrichum candidumThe screening of CGMCC 5066 :With the active sludge of sewage work as the bacterial classification sample of originating; Prepare substratum by ordinary method, adopt dilution spread plate partition method that sample is carried out microbial strains and separate, behind single bacterium colony to be formed; By the used solid medium obtaining liq substratum of each single bacterium colony; By ordinary method single colony inoculation is carried out the concussion of airbath oscillator in liquid nutrient medium and cultivate, be prepared into microbial culture medium, then institute's cultured microorganism is carried out primary dcreening operation.

The method of primary dcreening operation is: the concentration of in test tube, packing into is the Kaolin clay suspension 20ml of 4g/L; Whether add the microbial fermentation solution after 2-3 drips cultivation, observing has floc sedimentation to generate, if there is floc sedimentation to generate; Explain that then this bacterium has flocculating effect, can cultivate as microbial flocculant.With the bacterial isolates that obtains with flocculating effect, adopt plate streak that the bacterial isolates of being cultivated is separated and purifying, obtain pure bacterial strain; And be prepared into microbial culture medium, and Kaolin clay suspension is carried out flocculation treatment, the bacterial classification that institute's producing microbial flocculation agent flocculating rate is the highest is as research object; And identify that authentication method is: this bacterium goes up growth fast at wort agar substratum (MEA), and 25 ℃ of dark conditions were cultivated 14 days down; Colony diameter 50-60mm; White, tiling, powdery; The bacterium colony back side is light brown, does not have water-soluble pigment, and the vegetative hyphae wall is smooth, does not have and separates, tool branch, wide 2.5-5.5 μ m.Produce arthrospore, column, long 4.0-44.2 μ m with the mycelia fracture mode; With mycelia with wide; Not seeing has condition to produce spore structure, and the exocytosis thing of its generation has good turbidity removal decoloring ability, adopts molecular biology method to carry out rrna rRNA sequential analysis simultaneously and detects; According to experimental data analysis-by-synthesis such as cultural characteristic, microscopic morphology and gene sequence characteristics, this bacterial classification be geotrichum candidum ( Geotrichum candidum), laboratory called after Mva, and through China Committee for Culture Collection of Microorganisms common micro-organisms center (CGMCC) preservation, preserving number is CGMCC 5066.

Confirming as follows of flocculating rate: in the 1000ml beaker, add 1000ml zero(ppm) water, 4g kaolin, the CaCl of 0.2g ₂, the kaolin suspension liquid of preparation 4g/L.Measure the kaolin suspension liquid of 100ml with graduated cylinder, add a certain amount of microbial culture medium, leave standstill 3min after the stirring, get 50ml place supernatant and on 722 type spectrophotometers, measure OD value OD550, compare, the calculating flocculating rate with the OD value before the flocculation.

The method of calculation of flocculating rate: E (%)=(A-B)/A * 100%, wherein, A is the OD value at 550nm place before the flocculation treatment; B is the OD value at 550nm place after the flocculation treatment.

Aforesaid screening to bacterial strain, its conventional substratum is solid medium or liquid nutrient medium.

Aforesaid solid medium, it is in beef-protein medium, Gause I substratum or the general fermention medium any one.

Preferably, aforesaid solid medium is the Cha Shi substratum.

According to the present invention; Utilize the waste water of sewage work to filter out the bacterial strain that a strain can be used as microbial flocculant production bacterium; And directly utilize cake factory or distillery waste to produce microbial flocculant; Not only greatly reduce the production cost of microbial flocculant,, also played good effect simultaneously for the protection of environment for an outlet has been found in the increment utilization of food service industry by product.

Embodiment

Embodiment 1

Geotrichum candidumThe screening of CGMCC 5066

1, the preparation of microbial culture medium: as the bacterial classification sample of originating, adopt the Cha Shi substratum with the active sludge of sewage work, its composition is: sucrose 6g, FeSO ₄0.002g, K ₂PO ₄1.0g, (NH ₄) ₂SO ₄1.0g, KCl 0.5g, NaNO ₃3.0g, MgSO ₄0.5g, agar 15g, H ₂O 1000ml, pH7.0; Adopting dilution spread plate partition method that sample is carried out microbial strains separates; Behind single bacterium colony to be formed; Preparation Cha Shi liquid nutrient medium carries out the concussion of airbath oscillator by ordinary method with single colony inoculation and cultivates in liquid nutrient medium, be prepared into microbial culture medium.

2, institute's cultured microorganism is carried out primary dcreening operation:

The method of primary dcreening operation is: the concentration of in test tube, packing into is the Kaolin clay suspension 20ml of 4g/L; Whether add the microbial fermentation solution after 2-3 drips cultivation, observing has floc sedimentation to generate, if there is floc sedimentation to generate; Explain that then this bacterium has flocculating effect, can cultivate as microbial flocculant.With the bacterial isolates that obtains with flocculating effect, adopt plate streak that the bacterial isolates of being cultivated is separated and purifying, obtain pure bacterial strain, and be prepared into microbial culture medium, Kaolin clay suspension is carried out flocculation treatment, measure its flocculating rate.

3, confirming of flocculating rate: in the 1000ml beaker, add 1000ml zero(ppm) water, 4g kaolin, the CaCl of 0.2g ₂, be mixed with the kaolin suspension liquid of 4g/L.Measure the kaolin suspension liquid of 100ml with graduated cylinder, add a certain amount of microbial culture medium, leave standstill 3min after the stirring, get 50ml place supernatant and on 722 type spectrophotometers, measure OD value OD550, compare, the calculating flocculating rate with the OD value before the flocculation.

4, with the bacterial classification of institute's producing microbial flocculation agent flocculating rate the highest (flocculating rate is 94%) as research object, and identify: this bacterium goes up growth fast at wort agar substratum (MEA), and 25 ℃ of dark conditions were cultivated 14 days down; Colony diameter 50-60mm; White, tiling, powdery; The bacterium colony back side is light brown, does not have water-soluble pigment, and the vegetative hyphae wall is smooth, does not have and separates, tool branch, wide 2.5-5.5 μ m.Produce arthrospore with the mycelia fracture mode, column, long 4.0-44.2 μ m; With mycelia with wide; Not seeing has condition to produce spore structure, and the exocytosis thing of its generation has good turbidity removal decoloring ability, adopts molecular biology method to carry out rrna rRNA sequential analysis simultaneously and detects; According to experimental data analysis-by-synthesis such as cultural characteristic, microscopic morphology and gene sequence characteristics, this bacterial classification be geotrichum candidum ( Geotrichum candidum), laboratory called after Mva, and be CGMCC 5066 through preservation.

Embodiment 2

Utilize distillery waste to prepare microbial flocculant

1, bacterial classification: Geotrichum candidumCGMCC 5066.

2, microbial flocculant is produced the preparation of the liquid nutrient medium of bacterium:

Seed culture medium: in 1000ml zero(ppm) water, sucrose 18g, FeSO ₄0.006g, K ₂PO ₄0.6g, (NH ₄) ₂SO ₄0.6g, KCl 0.3g, NaNO ₃1.8g, MgSO ₄120.3g.

Fermention medium: with 100 times of distillery waste dilutions, the pH value is adjusted to 5.5, high pressure steam sterilization.

3, microbial flocculant is produced the preparation of bacterium:

Seed culture: will Geotrichum candidumCGMCC 5066 bacterium are inserted seed culture medium (250ml triangular flask, liquid amount 50ml), 30 ℃ of culture temperature, shaking speed 150rpm, aerobic cultivation 24h.

Fermentation culture: will Geotrichum candidumCGMCC 5066 seed liquor by volume 4% inoculum size insert in the fermentation culture, during uses concentration as the sodium hydroxide solution control pH value of 5M 5～6,37 ℃ of culture temperature, rotating speed 160rpm, 48h fermentation ends, acquisition Geotrichum candidumCGMCC 5066 fermented liquids.

4, the preparation of microbial flocculant and application:

Centrifugal 25min under the 9000rpm condition removes thalline with fermented liquid; 4 ℃ the ethanol that liquid after the spinning is added 3 times of volumes; More than 4 ℃ of condition held 12h; It is thus clear that flocculation sediment deposits yields, this flocculate precipitate are flocculation agent, centrifugal 30min separates ethanol with flocculate precipitate under the 4000rpm condition.Is 60 ℃ with the flocculate precipitate after centrifugal in temperature, and vacuum tightness is vacuum-drying 5h under the condition of 0.06MPa, can obtain the solid flocculation agent.During application, flocculation agent adds the water with centrifuged supernatant equivalent, and mixing is for use.In the waste water that needs to handle per ton, add 250g calcium chloride earlier, add the 50L microbial flocculant again, regulate the pH value with sodium hydroxide behind the mixing and make it maintain 4.0 ~ 8.0, fully shake up standing sedimentation.

5, the mensuration of flocculating rate: in 100 milliliter 0.4% kaolin, add 1 milliliter of 1% calcium chloride solution earlier, add the 0.05ml microbial flocculant again; Adjust pH fully behind the mixing, did not leave standstill 6 minutes; The rapid conglomeration deposition of the muddy liquid of originally muddy kaolin, solid-liquid interface is clear, gets supernatant on 722 type spectrophotometers; Measure the OD value under the 550nm, compare with the OD value before the flocculation, flocculating rate is 97.2%.

Embodiment 3

Utilize cake factory processing waste water to produce microbial flocculant

1, bacterial classification: Geotrichum candidumCGMCC 5066.

2, microbial flocculant is produced the preparation of the liquid nutrient medium of bacterium:

Seed culture medium: in 1000ml zero(ppm) water, sucrose 18g, FeSO ₄0.006g, K ₂PO ₄0.6g, (NH ₄) ₂SO ₄0.6g, KCl 0.3g, NaNO ₃1.8g, MgSO ₄120.3g;

Fermention medium: the pH value of cake factory waste water is adjusted to 6.5, high pressure steam sterilization.

3, microbial flocculant is produced the preparation of bacterium:

Seed culture: will Geotrichum candidumCGMCC 5066 bacterium are inserted in the seed culture medium (250ml triangular flask, liquid amount 100ml), then 35 ℃ of culture temperature, and shaking speed 150rpm, aerobic cultivation 24h obtains Geotrichum candidumCGMCC 5066 seed culture fluids.

Fermentation culture: with sodium hydroxide fermentation culture pH value is adjusted to 6.5, will Geotrichum candidumCGMCC 5066 seed liquor by volume 5% inoculum size insert in the fermentation culture, 35 ℃ of culture temperature, and rotating speed 180rpm, the 24h fermentation ends obtains Geotrichum candidumCGMCC 5066 fermented liquids.

4, the preparation of microbial flocculant and application:

Centrifugal 25min under the 9000rpm condition removes thalline with fermented liquid; 4 ℃ the ethanol that liquid after the spinning is added 3 times of volumes; More than 4 ℃ of condition held 12h; It is thus clear that flocculation sediment deposits yields, this flocculate precipitate are flocculation agent, centrifugal 30min separates ethanol with flocculate precipitate under the 4000rpm condition.Is 60 ℃ with the flocculate precipitate after centrifugal in temperature, and vacuum tightness is vacuum-drying 5-6h under the condition of 0.06MPa, can obtain the solid flocculation agent.During application, flocculation agent adds the water with centrifuged supernatant equivalent, and mixing is for use.Add the 20L flocculation agent in the waste water per ton, fully shake up standing sedimentation.

5, confirming of flocculating rate: in 100 milliliter 0.4% kaolin, add 1 milliliter of 1% calcium chloride solution earlier, add the 0.02ml microbial flocculant again; Adjust pH fully behind the mixing, did not leave standstill 6 minutes; The rapid conglomeration deposition of the muddy liquid of originally muddy kaolin, solid-liquid interface is clear, gets supernatant in the OD value of measuring on the 722 type spectrophotometers under the 550nm; Compare flocculating rate reached to 96.8% with the OD value before the flocculation.

Embodiment 4

1, bacterial classification: Geotrichum candidumCGMCC 5066.

2, microbial flocculant is produced the preparation of the liquid nutrient medium of bacterium:

Seed culture medium: in 1000ml zero(ppm) water, sucrose 18g, FeSO ₄0.006g, K ₂PO ₄0.6g, (NH ₄) ₂SO ₄0.6g, KCl 0.3g, NaNO ₃1.8g, MgSO ₄120.3g;

Fermention medium: with 100 times of distillery waste dilutions, the pH value is adjusted to 7.5, high pressure steam sterilization.

3, microbial flocculant is produced the preparation of bacterium:

Seed culture: will Geotrichum candidumCGMCC 5066 bacterium are inserted seed culture medium (250ml triangular flask, liquid amount 50ml), 37 ℃ of culture temperature, shaking speed 150rpm, aerobic cultivation 24h;

Fermentation culture: will Geotrichum candidumCGMCC 5066 seed liquor by volume 4% inoculum size insert in the fermentation culture, during uses concentration as the sodium hydroxide solution control pH value of 5M 5～6,37 ℃ of culture temperature, rotating speed 160rpm, 48h fermentation ends, acquisition Geotrichum candidumCGMCC 5066 fermented liquids.

4, the preparation of microbial flocculant and application:

Fermented liquid is removed thalline at the centrifugal 25min of 9000rpm; 4 ℃ the ethanol that liquid after the spinning is added 3 times of volumes; More than 4 ℃ of condition held 12h; It is thus clear that flocculation sediment deposits yields, this flocculate precipitate are flocculation agent, centrifugal 30min separates ethanol with flocculate precipitate under the 4000rpm condition.Is 60 ℃ with the flocculate precipitate after centrifugal in temperature, and vacuum tightness is vacuum-drying 5h under the condition of 0.06MPa, can obtain the solid flocculation agent.

In 100 milliliters of orchils, add the 0.2ml microbial flocculant, fully mixing leaves standstill and promptly produces significantly flocculation phenomenon a moment; The bulk floc settlement is arranged, and supernatant fluid color is removed basically, leave standstill 1h after; Get supernatant in the OD value of measuring on the 722 type spectrophotometers under the 550nm; Compare with the supernatant before adding flocculation agent, the colorimetric estimation percent of decolourization reaches 75.5%, and flocculating rate is 65.9%.

For when using, the usage quantity of flocculation agent, those skilled in the art can control as the case may be well.

Claims (10)

1. utilize cake factory or distillery waste to prepare the production bacterium of microbial flocculant, it is characterized in that this bacterial strain Geotrichum candidumThe flocculation agent that screens in the active sludge for sewage work is produced bacterium, and through China Committee for Culture Collection of Microorganisms common micro-organisms center (CGMCC) preservation, preserving number is: CGMCC 5066.

2. the preparation method of a microbial flocculant comprises and uses mikrobe to carry out the preparation of flocculation agent, it is characterized in that, comprises the steps:

(a), the screening flocculation agent is produced bacteria strain from the active sludge of sewage work Geotrichum candidum

(b), utilize the waste water of cake factory or brewery to prepare microbial flocculant: at first will Geotrichum candidumBacterium is linked in the seed culture medium, under 30 ~ 37 ℃ of conditions, cultivates 18 ~ 36h, obtains seed liquor;

(c), above-mentioned seed liquor is joined in the fermention medium of the brewery of high pressure steam sterilization or cake factory waste water by the inoculum size that accounts for wastewater volume 1 ~ 10%, and under 30 ~ 40 ℃ of conditions, carry out aerobic fermentation;

(d), during the fermentation, the rotating speed of shaking table is controlled at 60 ~ 200rpm, and adopts the scope of the alkaline solution adjusting pH value 5 ~ 8 of 1 ~ 5M;

(e), can obtain microbial fermentation solution behind fermentation 24 ~ 72h;

(f), the fermented liquid that obtains centrifugal 20 ~ 30min under the 6000-9000rpm condition is removed thalline, the liquid after the spinning is joined in 4 ℃ the ethanol that is equivalent to 3 times of volumes of fermented liquid, and at 4 ℃ of condition held 12h at least;

(g), centrifugal 30min separates ethanol with flocculate precipitate under the 4000rpm condition, be that 60 ± 2 ℃, vacuum tightness are vacuum-drying 5 ~ 6h under the condition of 0.06MPa with the flocculate precipitate after centrifugal in temperature, can obtain the solid flocculation agent.

3. preparation method according to claim 2 is characterized in that, in claim 2 step (c) before, earlier with 20 ~ 200 times of distillery waste dilutions, and adjusting pH value is 5 ~ 7.

4. preparation method according to claim 3 is characterized in that, the seed liquor volume that carries out fermentation culture accounts for 4 ~ 8% of dilution back distillery waste.

5. preparation method according to claim 2 is characterized in that, in claim 2 step (c) before, the pH value of cake factory waste water is transferred to 5 ~ 8.

6. microbial flocculant, it utilizes according to claim 3 or 4 described preparing methods' preparations.

7. microbial flocculant, it utilizes preparing method's preparation according to claim 5.

8. the method for use of microbial flocculant according to claim 6 is characterized in that, the flocculation agent that obtains is when using, and with the water of solid part adding with centrifuged supernatant equivalent, mixing is for use earlier.

9. the method for use of microbial flocculant according to claim 7 is characterized in that, the flocculation agent that obtains is when using, and with the water of solid part adding with centrifuged supernatant equivalent, mixing is for use earlier.

10. the method for use of microbial flocculant according to claim 8; It is characterized in that; The flocculation agent that obtains add 0 ~ 500g calcium chloride in the waste water that needs to handle per ton when using, add the 2-50L microbial flocculant behind the mixing again, regulates pH value 4.0 ~ 8.0 with sodium hydroxide behind the mixing; Fully shake up standing sedimentation.