Method for separation of biosulfur

Abstract

The present invention belongs to environmental protection purification technology, and relates to a separation method of biosulfur, which comprises: contacting a material containing biosulfur with an enzyme preparation, performing enzymolysis treatment, and obtaining a hydrolyzed material; contacting the hydrolyzed material with a modifier under an external voltage for flocculation treatment, and obtaining a flocculated product; performing solid-liquid separation on the flocculated product, and obtaining biosulfur; wherein the enzyme preparation is an enzyme preparation capable of degrading biopolymers. The present invention can quickly and efficiently separate biosulfur from effluent, and is suitable for the product of sulfur recovery processing unit in microbial desulfurization processes such as natural gas, biogas, coal-fired flue gas, and sulfur-containing wastewater. The operation is simple, the power consumption is low, the amount of composite enzyme preparation and modifier added is small, and the environment is friendly. The biosulfur recovery rate can reach more than 95%, and the sulfur purity can reach more than 90%.

Description

Technical Field

[0001] The invention relates to the field of environmental protection purification, and in particular to a method for separating biosulfur. Background Art

[0002] Biological desulfurization technology is a new process developed in the 1980s to replace conventional desulfurization. It has many advantages, such as no need for catalysts and oxidants, no need to treat chemical sludge, little biological pollution, low energy consumption, sulfur recovery, high efficiency, no odor, etc. The disadvantages are that the process is difficult to control and the conditions are demanding.

[0003] The elemental sulfur (biosulfur) obtained by biological transformation is very different from the chemical sulfur element in nature in many aspects. Lettinga et al. explored the characteristics of the biosulfur obtained by microbial transformation and observed the morphological characteristics of the biosulfur and found that the surface of the biosulfur was very rough and uneven. The protrusions on the surface were various biomacromolecules attached to the surface of the biosulfur particles, which formed a sharp contrast with the chemical sulfur particles. The surface of the chemical sulfur particles was very smooth and had a regular geometric shape. He found that the long-chain polymers on the surface of these biosulfur particles also carried negative charges, which had a significant negative effect on the aggregation and precipitation of sulfur particles. Therefore, the elemental sulfur obtained by biological transformation was in a colloidal state, not easy to settle and aggregate, and was suspended in water, making it difficult to separate from water.

[0004] At present, the commonly used methods for separating particulate matter mainly include gravity sedimentation, centrifugal sedimentation, flocculation sedimentation, flotation, etc. Regarding the separation method of biosulfur, the current research mainly focuses on the separation of biosulfur in the process of sulfide removal.

[0005] Janssen et al. found that the surface of biosulfur particles is negatively charged, so they proposed to use flocculation sedimentation method to achieve separation by adding cationic flocculants to the water containing biosulfur particles. Li Yaxin et al. believed that the flocculation sedimentation method can separate biosulfur particles from water, but because the flocculant will wrap the biosulfur particles inside, it will cause great difficulties for the subsequent solvent extraction crystallization purification.

[0006] Li Yaxin et al. studied the recovery of elemental sulfur from the effluent after sulfide was treated by a colorless sulfur bacteria biooxidation reactor, and proposed the use of a "slow filter filtration-sand scraping-extraction-distillation" process to achieve the recovery of elemental sulfur. By controlling the filtration rate in the slow sand filter, a 76.1% to 80.0% elemental sulfur recovery rate can be achieved. Although this process route is feasible, due to the high cost of extraction, high economic cost, and high toxicity, its engineering application needs to be studied.

[0007] Shell-Paques of the Netherlands uses flotation to recover biosulfur particles. Its process equipment mainly consists of flotation tanks, inclined plate sedimentation tanks, vacuum drum filters, heat exchangers and sulfur centrifuges. Its main principle is to blow biosulfur particles to the surface of the water body through flotation methods such as pressurized flotation or dissolved air flotation, and then scrape the biosulfur particles away from the water body through surface scrapers, and further centrifuge to finally separate the biosulfur particles. However, this method not only consumes a lot of energy and has a high economic cost, but also the biosulfur particles are easily oxidized by air during the flotation process, and is not suitable for large-scale use. Summary of the invention

[0008] The purpose of the present invention is to overcome the problems existing in the prior art and provide a method for separating biosulfur. The method realizes the separation of biosulfur by adding an enzyme preparation and a modifier combined with an electrode method, can separate biosulfur quickly and efficiently, and has simple operation, low cost, environmental friendliness, and high biosulfur recovery rate and sulfur purity.

[0009] In order to achieve the above-mentioned object, the present invention provides a method for separating biosulfur, which comprises: contacting a material containing biosulfur with an enzyme preparation, performing enzymatic hydrolysis treatment, and obtaining an enzymatically hydrolyzed material; contacting the enzymatically hydrolyzed material with a modifier under an external voltage for flocculation treatment, and obtaining a flocculated product; and performing solid-liquid separation on the flocculated product to obtain biosulfur;

[0010] Wherein, the enzyme preparation is an enzyme preparation capable of degrading biopolymers.

[0011] Preferably, the enzyme preparation is selected from at least one of protease, cellulase, lipase, nuclease and lysozyme.

[0012] Preferably, the modifier comprises a flocculant, a surfactant and a stabilizer.

[0013] The biosulfur separation method of the present invention can decompose the macromolecular polymers attached to the surface of biosulfur particles into biomicromolecules, and use them as a microbial nutrient source, so that the negatively charged attachments on the surface of the biosulfur are reduced, the absolute value of the Zeta potential can be reduced to below 10mV, and the sedimentation performance is improved. Then, an external voltage and a modifier are used to promote the coagulation and polymerization of biosulfur particles to form particle clusters, so that the sulfur particle size can be rapidly increased to more than 40μm, and the biosulfur particles are rapidly settled under the action of gravity and separated.

[0014] The present invention can separate biosulfur from effluent quickly and efficiently, the clear liquid can be recycled, the operation is simple, the power consumption is low, the amount of enzyme preparation and modifier added is small, and it is environmentally friendly. The biosulfur recovery rate can reach more than 95%, and the sulfur purity can reach more than 90%.

[0015] The biological sulfur separation method of the present invention can be used to process materials from sulfur recovery processing units in microbial desulfurization processes such as natural gas, biogas, coal-fired flue gas, and sulfur-containing wastewater. DETAILED DESCRIPTION

[0016] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0017] The invention provides a method for separating biosulfur, which comprises: contacting a material containing biosulfur with an enzyme preparation, performing enzymolysis treatment, and obtaining an enzymolyzed material; contacting the enzymolyzed material with a modifier under an external voltage for flocculation treatment, and obtaining a flocculated product; and performing solid-liquid separation on the flocculated product to obtain biosulfur; wherein the enzyme preparation is an enzyme preparation capable of degrading biopolymers.

[0018] In the present invention, the material containing biosulfur can come from the sulfur recovery unit in the microbial desulfurization process of natural gas, biogas, coal-fired flue gas, sulfur-containing wastewater, etc. Generally speaking, the surface of the sulfur particles in the material will be attached with biopolymers, such as polysaccharides, proteins and lipids.

[0019] Preferably, the content of biosulfur in the biosulfur-containing material is 0.1-10 mg / L, more preferably 0.5-5 mg / L.

[0020] The method for determining the content of biological sulfur adopts the sulfite method, see the document Reduction of produced elementary sulfur indenitrifying sulfide removal process. Environmental biotechnology, 2011, 90: 1129-1136.

[0021] Preferably, in the biosulfur-containing material, the particle size of the biosulfur is less than 10 μm and the Zeta potential is greater than 40 mV.

[0022] Preferably, the enzyme preparation is selected from at least one of protease, cellulase, lipase, nuclease and lysozyme.

[0023] Preferably, the protease is selected from at least one of papain, trypsin and subtilisin.

[0024] Preferably, the cellulase is at least one selected from β-glucanase, xylanase and β-glucosidase.

[0025] In the present invention, the enzyme preparations can all be obtained commercially.

[0026] Preferably, compared to 1g of biosulfur, the dosage of the protease is 100-5000U (for example, it can be 100, 500, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000U and any range between any two values).

[0027] Preferably, compared to 1 g of biosulfur, the dosage of the cellulase is 50-1000 U (for example, it can be 50, 100, 200, 400, 600, 800, 1000 U and any range between any two values).

[0028] Preferably, compared to 1 g of biosulfur, the dosage of the lipase is 10-500 U (for example, it can be 10, 50, 100, 200, 300, 400, 500 U and any range between any two values).

[0029] Preferably, compared to 1 g of biosulfur, the dosage of the nuclease is 10-500 U (for example, it can be 10, 50, 100, 200, 300, 400, 500 U and any range between any two values).

[0030] Preferably, compared to 1 g of biosulfur, the amount of lysozyme used is 10-200 U (for example, it can be 10, 50, 100, 150, 200 U and any range between any two values).

[0031] In a preferred embodiment of the present invention, the enzyme preparation comprises protease, cellulase, lipase, nuclease and lysozyme; wherein, compared to 1g of bio-sulfur, the dosage of the protease is 200-3000U; the dosage of the cellulase is 50-600U; the dosage of the lipase is 30-300U; the dosage of the nuclease is 30-300U; the dosage of the lysozyme is 20-100U.

[0032] Preferably, the enzyme preparation is in the form of immobilized enzyme.

[0033] In the present invention, electrolysis is performed by applying an external voltage to promote the directional aggregation of biosulfur particles in the system. Preferably, the voltage is 1-20V, preferably 5-15V.

[0034] In the present invention, by adding a modifier, the particle size of the sulfur particles is rapidly increased, the agglomeration and sedimentation of the biological sulfur particles are further promoted, and the rapid flocculation and separation of the biological sulfur is achieved.

[0035] Preferably, the modifier comprises a flocculant, a surfactant and a stabilizer.

[0036] Preferably, the flocculant is selected from at least two of a microbial flocculant, an organic polymer flocculant and an inorganic polymer flocculant.

[0037] Microbial flocculants are a type of high molecular weight organic matter produced by microorganisms with flocculation function. They mainly include glycoproteins, polysaccharides, cellulose and nucleic acids. They can be purchased commercially, such as microbial polysaccharide flocculants purchased from Weifang Yihao Biotechnology Co., Ltd.

[0038] The organic polymer flocculant may be a protein, a polysaccharide compound, a chitosan, etc., preferably at least one of chitosan, alginate, gelatin and modified starch.

[0039] The inorganic polymer flocculant is preferably polyaluminium chloride.

[0040] In a preferred embodiment of the present invention, the flocculant comprises a microbial polysaccharide flocculant, chitosan and polyaluminium chloride. Preferably, the content of the microbial polysaccharide flocculant in the flocculant is 25-35% by weight, the content of the chitosan is 20-30% by weight, and the content of the polyaluminium chloride is 40-50% by weight.

[0041] Preferably, the surfactant is a biosurfactant, preferably at least one selected from rhamnolipid, sophorolipid and surfactin.

[0042] Preferably, the stabilizer is selected from at least one of sorbitol, sucrose and lauric acid.

[0043] Preferably, compared to 1g of biosulfur, the amount of the flocculant is 5-15mg, the amount of the surfactant is 1-10mg, and the amount of the stabilizer is 2-5mg.

[0044] In the present invention, the modifier may further contain water.

[0045] After enzymatic hydrolysis and flocculation treatment, in the flocculated product, the particle size of the biosulfur particles is preferably above 35 μm, more preferably above 40 μm; the Zeta potential is preferably below 20 mV, more preferably below 10 mV.

[0046] In the present invention, the product after flocculation treatment is subjected to solid-liquid separation to obtain a solid phase and a liquid phase, wherein the solid phase contains biosulfur, and the liquid phase contains abundant biomolecules, which are nutrients required for microbial growth and can enter the biodesulfurization unit through a water pump for recycling.

[0047] The solid-liquid separation method may be a conventional method in the art, such as sedimentation.

[0048] In the present invention, the enzymatic hydrolysis treatment can be carried out in a pretreatment tank, the flocculation treatment can be carried out in a flocculation tank, and the solid-liquid separation can be carried out in a sedimentation tank.

[0049] The present invention will be described in detail below through examples.

[0050] In the following examples, unless otherwise specified, the reagents and materials used were commercially available.

[0051] Papain was purchased from Nanning Pangbo Bioengineering Co., Ltd., with an enzyme activity of 100,000 U / g;

[0052] β-glucanase was purchased from Shandong Longkote Enzyme Preparation Co., Ltd., with an enzyme activity of 50,000 U / g;

[0053] Lipase was purchased from Shandong Longkote Enzyme Preparation Co., Ltd., with an enzyme activity of 100,000 U / g;

[0054] Nuclease was purchased from Cangzhou Xiasheng Enzyme Biotechnology Co., Ltd., with an enzyme activity of 100,000 U / g;

[0055] Lysozyme was purchased from Nanning Pangbo Bioengineering Co., Ltd., with an enzyme activity of 20,000 U / g;

[0056] Trypsin was purchased from Fuzhou Feijing Biotechnology Co., Ltd., with an enzyme activity of 250,000 U / g;

[0057] Xylanase was purchased from Shandong Longkote Enzyme Preparation Co., Ltd., with an enzyme activity of 100,000 U / g;

[0058] The composite flocculant is composed of 30% by weight of biological flocculant, 25% by weight of chitosan and 45% by weight of polyaluminium chloride, wherein the biological flocculant is a microbial polysaccharide flocculant purchased from Weifang Yihao Biotechnology Co., Ltd.

[0059] Example 1

[0060] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into a pretreatment tank, and 5 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of papain, β-glucanase, lipase, nuclease and lysozyme is 6:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 10V voltage is applied, and 30 μg / L of a sulfur particle modifier is added, which is composed of 25% by weight of a composite flocculant, 7% by weight of surfactant and 12% by weight of sorbitol, and the rest is water.

[0061] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 43mV to 8mV, the particle size of the biosulfur particles in the flocculation tank increased from 7μm to 48μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 98% and the sulfur purity reached 92%.

[0062] Example 2

[0063] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into a pretreatment tank, and 5 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of papain, β-glucanase, lipase, nuclease and lysozyme is 6:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 5V voltage is applied, and 20 μg / L of a sulfur particle modifier is added, which is composed of 25% by weight of a composite flocculant, 7% by weight of surfactant and 12% by weight of sorbitol, and the rest is water.

[0064] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 43mV to 8mV, the particle size of the biosulfur particles in the flocculation tank increased from 7μm to 40μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 96% and the sulfur purity reached 90%.

[0065] Example 3

[0066] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into a pretreatment tank, and 10 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of papain, β-glucanase, lipase, nuclease and lysozyme is 6:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 10V voltage is applied, and 30 μg / L of a sulfur particle modifier is added, which is composed of 25% by weight of a composite flocculant, 7% by weight of surfactant and 12% by weight of sorbitol, and the rest is water.

[0067] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 43mV to 5mV, the particle size of the biosulfur particles in the flocculation tank increased from 7μm to 52μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 99% and the sulfur purity reached 93%.

[0068] Example 4

[0069] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into a pretreatment tank, and 10 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of papain, β-glucanase, lipase, nuclease and lysozyme is 6:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 5V voltage is applied, and 20 μg / L of a sulfur particle modifier is added, which is composed of 25% by weight of a composite flocculant, 7% by weight of surfactant and 12% by weight of sorbitol, and the rest is water.

[0070] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 43mV to 5mV, the particle size of the biosulfur particles in the flocculation tank increased from 7μm to 50μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 97% and the sulfur purity reached 91%.

[0071] Example 5

[0072] The treated biosulfur-containing effluent with a biosulfur content of 1407 μg / L is passed into a pretreatment tank, and 20 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of trypsin, xylanase, lipase, nuclease and lysozyme is 8:3:1:1:4. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, and a voltage of 15V is applied, and 50 μg / L of a sulfur particle modifier is added at the same time, which is composed of 20 weight % composite flocculant, 10 weight % rhamnolipid, 8 weight % lauric acid, and the rest is water.

[0073] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 48mV to 10mV, the particle size of the biosulfur particles in the flocculation tank increased from 5μm to 45μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 98% and the sulfur purity reached 93%.

[0074] Example 6

[0075] The treated biosulfur-containing effluent with a biosulfur content of 1407 μg / L is passed into a pretreatment tank, and 20 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of trypsin, xylanase, lipase, nuclease and lysozyme is 8:3:1:1:4. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 10V voltage is applied, and 40 μg / L of a sulfur particle modifier is added, which is composed of 20 weight % composite flocculant, 10 weight % rhamnolipid and 8 weight % lauric acid, and the rest is water.

[0076] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 48mV to 10mV, the particle size of the biosulfur particles in the flocculation tank increased from 5μm to 42μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 97% and the sulfur purity reached 91%.

[0077] Example 7

[0078] The treated biosulfur-containing effluent with a biosulfur content of 1407 μg / L is passed into a pretreatment tank, and 30 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of trypsin, xylanase, lipase, nuclease and lysozyme is 8:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 15V voltage is applied, and 50 μg / L of a sulfur particle modifier is added, which is composed of 20 weight % composite flocculant, 10 weight % rhamnolipid and 8 weight % lauric acid, and the rest is water.

[0079] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 48mV to 5mV, the particle size of the biosulfur particles in the flocculation tank increased from 5μm to 50μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 99% and the sulfur purity reached 94%.

[0080] Example 8

[0081] The treated biosulfur-containing effluent with a biosulfur content of 1407 μg / L is passed into a pretreatment tank, and 30 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of trypsin, xylanase, lipase, nuclease and lysozyme is 8:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank, a 10V voltage is applied, and 40 μg / L of a sulfur particle modifier is added, which is composed of 20 weight % composite flocculant, 10 weight % rhamnolipid and 8 weight % lauric acid, and the rest is water.

[0082] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 48mV to 5mV, the particle size of the biosulfur particles in the flocculation tank increased from 5μm to 45μm, and they flowed into the sedimentation tank for rapid separation. The biosulfur recovery rate reached 98% and the sulfur purity reached 92%.

[0083] Blank example

[0084] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into the pretreatment tank, and then flows into the flocculation tank and the sedimentation tank. No immobilized complex enzyme preparations and sulfur particle modifiers are added, and no external voltage is applied. The biosulfur particles are flocculated and settled only by their own gravity.

[0085] Half an hour later, there was no obvious flocculation of the biosulfur particles, the absolute value of the Zeta potential was still 42mV, the particle size of the biosulfur particles was within 10μm, the biosulfur recovery rate was less than 20%, and the sulfur purity was less than 40%.

[0086] Comparative Example 1

[0087] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into a pretreatment tank, and 50 μg / L of an immobilized composite enzyme preparation is added to the pretreatment tank, wherein the weight ratio of papain, β-glucanase, lipase, nuclease and lysozyme is 6:4:1:1:3. The hydrolyzed biosulfur-containing effluent flows into a flocculation tank without adding voltage or sulfur particle modifier.

[0088] After treatment, the absolute value of the Zeta potential of the biosulfur particles dropped from 43mV to 5mV, and the particle size of the biosulfur particles in the flocculation tank increased from 7μm to 25μm, flowing into the sedimentation tank for separation. The biosulfur recovery rate was 82% and the sulfur purity was 90%.

[0089] Comparative Example 2

[0090] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L was passed into the pretreatment tank without adding any immobilized complex enzyme preparation. The biosulfur-containing effluent flowed into the flocculation tank, with an external voltage of 30V, but without adding sulfur particle modifier.

[0091] The absolute value of the Zeta potential of the biosulfur particles in the flocculation tank dropped from 45mV to 28mV, and the particle size increased from 7μm to 18μm. They flowed into the sedimentation tank for separation. The biosulfur recovery rate was 75% and the sulfur purity was 68%.

[0092] Comparative Example 3

[0093] The treated biosulfur-containing effluent with a biosulfur content of 845 μg / L is passed into a pretreatment tank without adding any immobilized composite enzyme preparation. The biosulfur-containing effluent flows into a flocculation tank without applying an external voltage, and 100 μg / L of a sulfur particle modifier is added, which is composed of 25 wt% composite flocculant, 7 wt% surfactant and 12 wt% sorbitol, and the rest is water.

[0094] The absolute value of the Zeta potential of the biosulfur particles in the flocculation tank dropped from 45mV to 35mV, and the particle size increased from 7μm to 20μm. They flowed into the sedimentation tank for separation. The biosulfur recovery rate was 65% and the sulfur purity was 70%.

[0095] Comparing the implementation effects of Tables 1-3, it can be seen that under the same conditions, the biosulfur-containing effluent hydrolyzed by the immobilized composite enzyme preparation alone can greatly reduce the absolute value of the Zeta potential of the biosulfur particles and increase the particle size, and the biosulfur recovery rate and sulfur purity are increased to 82% and 90%, respectively, which is worse than the effect of using an external voltage or a sulfur particle modifier alone. However, it is obviously not as good as the effect of treating biosulfur in the embodiment, and the addition amount of the composite enzyme preparation and the modifier in the embodiment is small, and the power consumption is lower.

[0096] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for separating biosulfur, characterized in that: The method comprises: contacting a material containing biosulfur with an enzyme preparation to perform enzymolysis treatment to obtain an enzymolyzed material; contacting the enzymolyzed material with a modifier under an external voltage to perform flocculation treatment to obtain a flocculated product; and performing solid-liquid separation on the flocculated product to obtain biosulfur; Wherein, the enzyme preparation is an enzyme preparation capable of degrading biopolymers.

2. The separation method according to claim 1, wherein The biosulfur content of the biosulfur-containing material is 0.1-10 mg / L; and / or In the biosulfur-containing material, the particle size of the biosulfur is less than 10 μm and the Zeta potential is greater than 40 mV.

3. The separation method according to claim 1, wherein The content of biosulfur in the biosulfur-containing material is 0.5-5 mg / L.

4. The separation method according to any one of claims 1 to 3, wherein: The enzyme preparation is selected from at least one of protease, cellulase, lipase, nuclease and lysozyme.

5. The separation method according to claim 4, wherein: Compared with 1g of biological sulfur, the usage of the protease is 100-5000U.

6. The separation method according to claim 4, wherein: Compared with 1g of biological sulfur, the dosage of the cellulase is 50-1000U.

7. The separation method according to claim 4, wherein: Compared with 1g of biological sulfur, the dosage of the lipase is 10-500U.

8. The separation method according to claim 4, wherein: Compared with 1g of biological sulfur, the dosage of the nuclease is 10-500U.

9. The separation method according to claim 4, wherein: Compared with 1g of biological sulfur, the dosage of the lysozyme is 10-200U.

10. The separation method according to any one of claims 1 to 3, wherein: The enzyme preparation comprises protease, cellulase, lipase, nuclease and lysozyme; Wherein, compared with 1g of biological sulfur, the dosage of the protease is 200-3000U; the dosage of the cellulase is 50-600U; the dosage of the lipase is 30-300U; the dosage of the nuclease is 30-300U; and the dosage of the lysozyme is 20-100U.

11. The separation method according to claim 4, wherein: The protease is selected from at least one of papain, trypsin and subtilisin; and / or The cellulase is selected from at least one of β-glucanase, xylanase and β-glucosidase.

12. The separation method according to any one of claims 1 to 3, wherein: The voltage is 1-20V.

13. The separation method according to any one of claims 1 to 3, wherein: The voltage is 5-15V.

14. The separation method according to any one of claims 1 to 3, wherein: The modifier comprises a flocculant, a surfactant and a stabilizer; Wherein, compared with 1g of biosulfur, the dosage of the flocculant is 5-15mg, the dosage of the surfactant is 1-10mg, and the dosage of the stabilizer is 2-5mg.

15. The separation method according to claim 14, wherein: The flocculant is selected from at least two of a microbial flocculant, an organic polymer flocculant and an inorganic polymer flocculant.

16. The separation method according to claim 14, wherein: The surfactant is a biosurfactant.

17. The separation method according to claim 14, wherein: The surfactant is selected from at least one of rhamnolipid, sophorolipid and surfactin.

18. The method according to claim 14, wherein: The stabilizer is selected from at least one of sorbitol, sucrose and lauric acid.