Disclosure of Invention
The invention aims to provide a comprehensive utilization method of microbial fermentation waste liquid, which comprises the following steps: carrying out membrane separation on microbial fermentation liquor to prepare fermentation waste liquor and clear liquor, wherein the volume of solids in the fermentation waste liquor accounts for not less than 30% of the volume of the total fermentation waste liquor, and the clear liquor is used for separating and purifying a target product; acidifying the fermentation waste liquid, heating to 70-90 deg.C, cooling to room temperature, filtering to obtain filter residue for preparing feed, and recovering the filtrate for fermentation; or cooling the acidified fermentation waste liquid to 5-10 deg.C, heating to 70-90 deg.C, cooling to room temperature, filtering, and recovering the filtrate for fermentation.
In a preferred embodiment of the present invention, the microorganism is selected from any one of wild-type microorganisms or recombinant microorganisms or a combination thereof.
In a preferred embodiment of the present invention, the microorganism is selected from any one of bacillus, yeast, escherichia, pantoea, salmonella, corynebacterium glutamicum, escherichia coli, pantoea ananatis, or a combination thereof.
In a preferred technical scheme of the invention, the microorganism fermentation liquor is amino acid fermentation liquor, and the amino acid is any one of alanine, arginine, aspartic acid, asparagine, citrulline, cysteine, glutamic acid, glutamine, histidine, isoleucine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine.
In a preferred technical scheme of the invention, the membrane separation is any one or a combination of nanofiltration membrane separation, ultrafiltration membrane separation, common filtration membrane separation, ceramic membrane separation and ion exchange membrane separation.
In a preferred technical scheme of the invention, the solid volume in the fermentation waste liquid accounts for not less than 40% of the volume of the total fermentation waste liquid, and preferably not less than 60%.
In a preferred technical scheme of the present invention, in the step (1), the microorganism fermentation broth is subjected to inactivation treatment and then membrane separation, wherein the inactivation treatment is preferably selected from any one or a combination of dry heat sterilization, moist heat sterilization, autoclaving and plasma sterilization.
In the preferable technical scheme of the invention, in the step (1), the microbial fermentation waste liquid is subjected to membrane separation after being cooled to below 50 ℃.
In the preferred technical scheme of the invention, in the step (1), the transmembrane pressure of the membrane separation is not more than 0.5 MPa.
In the preferable technical scheme of the invention, in the step (2), the pH value of the acidified fermentation waste liquid is 1-6, preferably 3-4.
In a preferred technical scheme of the present invention, in the step (2), the acid for acidifying the fermentation waste liquid is selected from any one of sulfuric acid, hydrochloric acid, nitric acid and oxalic acid or a combination thereof.
In the preferable technical scheme of the invention, the cooling time in the step (2) is 0.5-12 hours, and the preferable time is 3-6 hours.
In the preferable technical scheme of the invention, after the temperature of the acidified fermentation waste liquid in the step (2) is raised to 70-90 ℃, the acidified fermentation waste liquid is maintained for 0.5-2 hours, and then the acidified fermentation waste liquid is cooled to room temperature.
In the preferred technical scheme of the invention, the acidified fermentation waste liquid in the step (2) is cooled to 5-10 ℃, kept stand for 0.1-2 hours, heated to 70-90 ℃, maintained for 0.5-2 hours and cooled to room temperature.
In the preferred technical scheme of the invention, the stirring temperature reduction is carried out in the step (2), and the preferred stirring speed is 10-50 r/min.
In a preferred embodiment of the present invention, the filtration in step (2) is any one of plate-and-frame filtration and centrifugal filtration.
In a preferred technical scheme of the invention, a filter aid can be further added in the step (2), and preferably, the filter aid is selected from any one or combination of rice hull powder, diatomite, paper pulp and talcum powder.
In a preferred technical scheme of the invention, the light transmittance of the filtrate is more than 60%, preferably more than 70%.
In the preferable technical scheme of the invention, the filtrate is used for separating and purifying the target product.
In the preferable technical scheme of the invention, the water content of the filter residue is less than 60%, preferably less than 50%.
In a preferred technical scheme of the invention, the filter residue is used as animal feed or agricultural fertilizer.
Another object of the present invention is to provide an animal feed composition or an agricultural fertilizer composition, the preparation method of which comprises the steps of:
(1) performing membrane separation on microbial fermentation liquor to prepare fermentation waste liquor and clear liquor, wherein the volume of solids in the fermentation waste liquor accounts for not less than 30% of the volume of the total fermentation waste liquor, and the clear liquor is used for separating and purifying a target product;
(2) acidifying the fermentation waste liquid, heating to 70-90 deg.C, maintaining for 0.5-2 hr, cooling to room temperature, filtering to obtain filter residue for preparing feed, and recovering the filtrate for fermentation; or cooling the acidified fermentation waste liquid to 5-10 deg.C, standing for 0.1-2 hr, heating to 70-90 deg.C, maintaining for 0.5-2 hr, cooling to room temperature, filtering to obtain filter residue for preparing feed, and recovering the filtrate for fermentation.
In a preferred embodiment of the present invention, the microorganism is selected from any one of wild-type microorganisms or recombinant microorganisms or a combination thereof.
In a preferred embodiment of the present invention, the microorganism is selected from any one of bacillus, yeast, escherichia, pantoea, salmonella, corynebacterium glutamicum, escherichia coli, pantoea ananatis, or a combination thereof.
In a preferred technical scheme of the invention, the microorganism fermentation liquor is amino acid fermentation liquor, and the amino acid is any one of alanine, arginine, aspartic acid, asparagine, citrulline, cysteine, glutamic acid, glutamine, histidine, isoleucine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine.
In a preferred technical scheme of the invention, the membrane separation is any one or a combination of nanofiltration membrane separation, ultrafiltration membrane separation, common filtration membrane separation, ceramic membrane separation and ion exchange membrane separation.
In a preferred technical scheme of the invention, the solid volume in the fermentation waste liquid accounts for not less than 40% of the volume of the total fermentation waste liquid, and preferably not less than 60%.
In a preferred technical scheme of the present invention, in the step (1), the microorganism fermentation broth is subjected to inactivation treatment and then membrane separation, wherein the inactivation treatment is preferably selected from any one or a combination of dry heat sterilization, moist heat sterilization, autoclaving and plasma sterilization.
In the preferable technical scheme of the invention, in the step (1), the microbial fermentation waste liquid is subjected to membrane separation after being cooled to below 50 ℃.
In the preferred technical scheme of the invention, in the step (1), the transmembrane pressure of the membrane separation is not more than 0.5 MPa.
In the preferable technical scheme of the invention, in the step (2), the pH value of the acidified fermentation waste liquid is 1-6, preferably 3-4.
In a preferred technical scheme of the present invention, in the step (2), the acid for acidifying the fermentation waste liquid is selected from any one of sulfuric acid, hydrochloric acid, nitric acid and oxalic acid or a combination thereof.
In the preferable technical scheme of the invention, the cooling time in the step (2) is 0.5-12 hours, and the preferable time is 3-6 hours.
In the preferred technical scheme of the invention, the stirring temperature reduction is carried out in the step (2), and the preferred stirring speed is 10-50 r/min.
In a preferred embodiment of the present invention, the filtration in step (2) is any one of plate-and-frame filtration and centrifugal filtration.
In a preferred technical scheme of the invention, a filter aid can be further added in the step (2), and preferably, the filter aid is selected from any one or combination of rice hull powder, diatomite, paper pulp and talcum powder.
In a preferred technical scheme of the invention, the light transmittance of the filtrate is more than 60%, preferably more than 70%.
In the preferable technical scheme of the invention, the filtrate is used for separating and purifying the target product.
In the preferable technical scheme of the invention, the water content of the filter residue is less than 60%, preferably less than 50%.
In a preferred technical scheme of the invention, the filter residue is used as animal feed or agricultural fertilizer.
Another object of the present invention is to provide an animal feed composition for use in feeding animals, which can be any one of chicken feed, duck feed, goose feed, pig feed, cattle feed, horse feed, donkey feed, cat feed, dog feed, fish feed, rabbit feed, and sheep feed.
Unless otherwise indicated, when the present invention relates to percentages between liquids, said percentages are volume/volume percentages; the invention relates to the percentage between liquid and solid, said percentage being volume/weight percentage; the invention relates to the percentages between solid and liquid, said percentages being weight/volume percentages; the balance being weight/weight percent.
The percentage of the solid volume of the fermentation waste liquid in the total volume of the fermentation waste liquid is as follows: and standing the fermentation waste liquid for 30 minutes after fully and uniformly stirring, wherein the volume of the precipitated solid accounts for the percentage of the total volume of the fermentation waste liquid.
Unless otherwise indicated, the following detection methods were employed in the present invention:
1. transmittance of filtrate: the filtrate was measured for light transmittance at a wavelength of 430nm with an ultraviolet spectrophotometer, and pure water was used as a blank.
2. Water content of filter cake: and (3) drying the filter cake in a precise air-blast drying oven to constant weight, wherein the water content is (total weight before drying-total weight after drying)/total weight before drying is 100%.
Compared with the prior art, the invention has the following beneficial technical effects:
1. according to the method for recycling the microbial fermentation waste liquid, a flocculating agent is not required to be added, solid-liquid separation in the fermentation waste liquid can be realized only through acidification, heating, cooling and filtration, and the separation effect is good.
2. Organic matters such as microbial cells in the fermentation waste liquid are recycled to be used for preparing agricultural fertilizers or animal feeds and the like, so that the generation and recycling treatment of three wastes can be reduced, the comprehensive utilization of resources is promoted, the environment is protected, and the production cost is obviously reduced.
Detailed Description
In an alanine fermentation workshop, taking L-alanine fermentation liquid, heating the fermentation liquid to 80 ℃, and maintaining for 20 min. And then cooling the temperature of the fermentation liquor to 50 ℃, and carrying out ceramic membrane separation, wherein the operating pressure is not more than 0.5MPa, the operating temperature is not more than 70 ℃, and the ceramic membrane concentrated phase separation multiple is controlled to be 28 times. Separating by ceramic membrane to obtain clear liquid and fermentation waste liquid. And (5) further processing the clear solution by resin, decoloring, processing by an ultrafiltration membrane, concentrating, crystallizing, drying and packaging to finally obtain the target product. 10 liters of the fermentation waste liquid was sufficiently stirred and left to stand for 30 minutes, and the volume of the solid in the fermentation waste liquid was 40% based on the volume of the total fermentation waste liquid, and the fermentation waste liquid was used in comparative examples 1 to 3 and examples 1 to 7.
Comparative example 1
(1) Adding concentrated sulfuric acid into 500mL of fermentation waste liquid to adjust the pH value to 2.0, and maintaining for 1h under stirring;
(2) standing for 4 hours to naturally cool the fermentation waste liquid to room temperature;
(3) and (3) performing plate-and-frame filtration separation on the fermentation waste liquid, wherein the total filtration time is 34min, so as to obtain filtrate and filter cakes, the filtrate is turbid and has light yellow color, and the filtrate further returns to the clear liquid to separate and purify the target product. And unloading filter residues, drying, bagging and collecting the filter residues for preparing agricultural fertilizer or animal feed.
Comparative example 2
(1) Adding concentrated sulfuric acid into 500mL of fermentation waste liquid to adjust the pH value to 2.0, and maintaining for 1h under stirring;
(2) adding 20ml of polyaluminium chloride into the acidified fermentation waste liquid, and uniformly stirring;
(3) standing for 4 hours to naturally cool the fermentation waste liquid to room temperature;
(4) and (3) performing plate-and-frame filtration separation on the fermentation waste liquid, wherein the total filtration time is 34min, so as to obtain filtrate and filter cakes, the filtrate is turbid and has light yellow color, and the filtrate further returns to the clear liquid to separate and purify the target product. And unloading filter residues, drying, bagging and collecting the filter residues for preparing agricultural fertilizer or animal feed.
Comparative example 3
(1) Adding concentrated sulfuric acid into 500mL of fermentation waste liquid to adjust the pH value to 2.0, and maintaining for 1h under stirring;
(2) adding 20ml of polyacrylamide into the acidified fermentation waste liquid, and uniformly stirring;
(3) standing for 4 hours to naturally cool the fermentation waste liquid to room temperature;
(4) and (3) performing plate-and-frame filtration separation on the fermentation waste liquid, wherein the total filtration time is 34min, so as to obtain filtrate and filter cakes, the filtrate is turbid and has light yellow color, and the filtrate further returns to the clear liquid to separate and purify the target product. And unloading filter residues, drying, bagging and collecting the filter residues for preparing agricultural fertilizer or animal feed.