Complex microbial inoculant for high-temperature composting and rapid decomposition of livestock and poultry manure and straw cellulose and preparation method of complex microbial inoculant

Abstract

The invention relates to the technical field of agricultural wastes and microorganisms, in particular to a complex microbial inoculant for high-temperature composting and rapid decomposition of livestock and poultry manure and straw cellulose and a preparation method of the complex microbial inoculant. The compound microorganism bacterial liquid comprises streptomyces thermocarbonic oxide, bacillus stearothermophilus, bacillus subtilis, bacillus licheniformis, phanerochaete chrysosporium, trichoderma viride and aspergillus niger, and the bacterial liquid carrier is obtained by compounding modified charcoal and modified sepiolite through amidation reaction. According to the complex microbial inoculant provided by the invention, through the synergistic effect of the seven functional complementary microbial strains and the special three-dimensional reticulate carrier, rapid decomposition of high-temperature compost of livestock and poultry manure and straw cellulose is realized.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural waste and microorganisms, and in particular to a composite bacterial agent for high-temperature composting and rapid decomposition of livestock and poultry excrement and straw cellulose and a preparation method thereof. Background Art

[0002] With the development of large-scale agricultural production and intensive animal husbandry, the amount of livestock and poultry manure and crop straw has increased dramatically. How to efficiently deal with these agricultural wastes has become an environmental problem that needs to be solved urgently. As an economical and effective treatment method, high-temperature composting can convert organic matter in livestock and poultry manure and straw into stable humus, which not only reduces environmental pollution but also realizes resource utilization. The high-temperature composting process of livestock and poultry manure and straw cellulose usually includes three stages: warming period, high temperature period and decomposition period. In the high temperature period (55-70℃), macromolecular organic substances such as cellulose and hemicellulose degrade most rapidly. However, since straw contains a large amount of lignin-cellulose composite structure, its compact physical and chemical structure hinders the degradation of cellulose by microorganisms, making the traditional composting cycle generally longer (3-6 months), resulting in a series of problems such as large area occupied, insufficient decomposition, and odor pollution.

[0003] At present, composite microbial agents have become the main technical means to accelerate the high-temperature composting of livestock and poultry manure and straw cellulose. For example, the existing Chinese patent CN202211211728.X discloses a composite microbial agent for high-temperature composting of straw, which contains Bacillus subtilis, Trichoderma pseudokoningii, Penicillium oxalicum and Aspergillus niger. These strains are cultured separately and then mixed, and nutrients and adsorption carriers are added, and finally the finished product is obtained by spray drying. However, the prior art has the following obvious defects: First, most composite agents lack microbial strains specifically for high-temperature stage activity, resulting in a decrease in microbial activity during the high-temperature period of composting and low efficiency of organic matter degradation; secondly, the microbial composition in the existing agents is single, lacking professional strains for lignin degradation, and it is difficult to effectively destroy the lignin-cellulose composite structure; thirdly, the carrier of the existing agent is usually a simple inorganic material or organic substance, lacking functional design, and cannot provide a stable growth environment and necessary protection for microorganisms. In the high-temperature, high-humidity and complex environment of composting, the survival rate and activity of microorganisms are difficult to guarantee. These factors together limit the application effect of existing composite bacterial agents in high-temperature composting of livestock and poultry manure and straw cellulose, making it difficult to meet the actual needs of rapid decomposition. Summary of the invention

[0004] In view of this, the present invention proposes a composite bacterial agent for rapid decomposition of livestock and poultry manure and straw cellulose at high temperature composting and a preparation method thereof, so as to solve the problems in the prior art of low composting efficiency caused by lack of high temperature active bacteria, single microbial composition, insufficient carrier functionality, etc.

[0005] The technical solution of the present invention is realized as follows: The present invention provides a composite microbial agent for rapid composting and rapid decomposition of livestock and poultry manure and straw cellulose, which includes a composite microbial liquid and a liquid carrier. The composite microbial liquid includes Streptomyces thermocarboxydus, Bacillus stearothermophilus, Bacillus subtilis, Bacillus licheniformis, Phanerochaete chrysosporium, Trichoderma viride, and Aspergillus niger. The liquid carrier is obtained by amide reaction of modified biochar and modified sepiolite.

[0006] The composite microbial agent provided by the present invention realizes the rapid composting process of livestock and poultry manure and straw cellulose through the synergistic effect of seven functionally complementary microbial strains and a special composite carrier. This composite microbial agent can quickly raise the temperature of the compost pile to the high-temperature range and maintain it for a long time at the initial stage of composting, effectively killing pathogenic microorganisms; at the same time, it forms a complete organic matter degradation chain, especially being able to efficiently break down the difficult-to-degrade lignin-cellulose composite structure in straw, significantly accelerating the conversion and utilization of cellulose; the composite microbial agent can also effectively reduce the emission of odors such as ammonia and hydrogen sulfide during the composting process, reduce nitrogen volatilization loss, and promote the activation of mineral elements and the formation of humus. The liquid carrier provides a stable living microenvironment for each functional strain through a special amide composite structure, significantly improving the survival rate and activity of microorganisms in the high-temperature, high-humidity, and complex composting environment, shortening the composting cycle, and improving the composting efficiency.

[0007] On the basis of the above technical solution, preferably, the composite microbial liquid, by mass percentage, includes 20-30% of Streptomyces thermocarboxydus, 20-25% of Bacillus stearothermophilus, 15-25% of Bacillus subtilis, 10-20% of Bacillus licheniformis, 5-10% of Phanerochaete chrysosporium, 5-8% of Aspergillus niger, and 5-10% of Trichoderma viride.

[0008] Specifically, Streptomyces thermocarboxydus and Bacillus stearothermophilus rapidly proliferate in the initial stage of composting, utilize carbohydrates, proteins, etc. to generate a large amount of heat energy, rapidly raise the temperature of the compost pile to 55 - 70 °C or even higher, accelerate the decomposition of organic matter and kill pathogenic bacteria; Phanerochaete chrysosporium secretes lignin peroxidase, manganese peroxidase and laccase, destroys the lignin - cellulose composite structure, releases carbon sources that can be utilized by microorganisms, and solves the problem of rate - limiting degradation of lignocellulose in composting; Trichoderma viride produces highly active cellulase, decomposes cellulose into glucose, which is further metabolized and utilized by other strains; Bacillus subtilis and Bacillus licheniformis secrete protease and amylase, decompose proteins and starches in livestock and poultry manure to produce amino acids and monosaccharides, provide small - molecule nutrients for the growth of other microorganisms and fix nutrients, reduce the emission of odors such as ammonia and hydrogen sulfide, reduce nitrogen volatilization loss, and increase the total nitrogen content of compost; Aspergillus niger secretes organic acids (such as citric acid, oxalic acid), promotes the dissolution of mineral elements such as phosphorus and potassium, and accelerates the formation of humus through metabolism to produce humic acid precursors.

[0009] On the basis of the above - mentioned technical solutions, preferably, the preparation method of the bacterial liquid carrier includes the following steps:

[0010] S1. Disperse iron - based biochar in anhydrous ethanol, add hexamethylene diisocyanate, react at 40 - 60 °C for 4 - 5 h, then add urea, and react at 60 - 80 °C for 6 - 8 h to obtain modified biochar;

[0011] S2. Disperse acid - treated sepiolite in water, add mercapto trimethoxysilane and carboxymethyl trimethoxysilane, react at 70 - 80 °C for 6 - 8 h to obtain silylated sepiolite;

[0012] S3. Disperse silylated sepiolite and vinyl anthraquinone in an aqueous DMF solution, add azobisisobutyronitrile, react at 60 - 70 °C for 5 - 7 h to obtain modified sepiolite;

[0013] S4. Disperse modified biochar and modified sepiolite in DMF, add EDC / HOBt as a condensing agent, react at room temperature for 10 - 12 h under nitrogen protection to obtain the bacterial liquid carrier.

[0014] Specifically, in step S1, the urea is covalently bonded to the iron-based biochar by the reaction of the hydroxyl groups on the iron-based biochar and the amino groups in the urea molecules with the isocyanate groups respectively, providing a continuous and stable nutrient supply for microorganisms. Meanwhile, the introduction of urea can also improve the hydrophilicity and microbial affinity of the biochar, and improve the attachment ability and survival environment of microorganisms on its surface. In step S2, through the silicon-oxygen bond network formed on the surface of sepiolite by the silane coupling agent, and at the same time, two functional groups, mercapto and carboxyl groups, are introduced on the surface of sepiolite. The silanization modification of sepiolite significantly improves the organic compatibility and dispersion stability of sepiolite, reduces the problem of the reduction of the effective specific surface area caused by easy agglomeration of traditional carrier materials during use, and provides a more uniform and stable attachment surface for microorganisms. In step S3, through the reaction of the unsaturated bonds in the mercapto groups loaded on the silanized sepiolite and vinyl anthraquinone, the anthraquinone structure is firmly bonded to the surface of sepiolite. The anthraquinone functionalization is particularly beneficial to improving the activity of the lignin-degrading enzyme system, can effectively break through the "bottleneck problem" of the lignin-cellulose composite structure during the composting process, and accelerate the conversion of the refractory organic matter in the straw; at the same time, the anthraquinone structure can also promote the redox metabolism of thermophilic bacteria and accelerate the composting heating and organic matter degradation process. In step S4, the two functionalized materials are covalently bonded through the reaction of the carboxyl groups on the surface of the modified sepiolite and the amino groups of the modified biochar, forming a composite carrier system with a three-dimensional network structure. This system simultaneously has the nitrogen source slow-release function of the iron-based biochar and the electron transfer function of the modified sepiolite, realizing the synergistic effect of "1 + 1 > 2". The composite carrier material has a richer microporous and mesoporous structure, providing an ideal attachment site and survival microenvironment for various microorganisms, and can effectively protect the activity of microorganisms during the high-temperature stage of composting; the three-dimensional network structure also significantly improves the mechanical strength and environmental stability of the carrier, ensuring the structural integrity during physical disturbance processes such as compost turning and continuously playing its function.

[0015] On the basis of the above technical solutions, preferably, the preparation method of the iron-based biochar in step S1 includes: impregnating the biomass powder in the FeSO4·7H2O solution, adding a hydrogen peroxide solution with a mass percentage of 25 - 35%, mixing and stirring at 25 - 30 °C for 10 - 15 h and then drying, and carbonizing at 300 - 350 °C for 2 - 3 h to obtain the iron-based biochar. More preferably, the mass ratio of the biomass powder, FeSO4·7H2O solution and hydrogen peroxide solution added is 2 - 5:4 - 8:0.1 - 1; the concentration of the FeSO4·7H2O solution is 0.7 - 0.8 mol / L.

[0016] More preferably, the biomass powder is sourced from one or more of rice straw, corn straw, and wheat straw.

[0017] Specifically, through the redox reaction of hydrogen peroxide and ferrous sulfate, the in-situ loading and catalytic conversion of iron ions on the biomass matrix are realized, and at the same time, abundant active sites such as surface hydroxyl groups, phenolic hydroxyl groups, and carboxyl groups are retained. As an electron transfer medium, nano-iron oxides can significantly promote the activity of redox enzymes of thermophilic microorganisms when loaded on biochar, accelerating electron transfer and energy metabolism during the composting process; at the same time, iron elements, as cofactors of various oxidases and peroxidases, can particularly promote the activity of lignin-degrading enzyme systems, and cooperate with the anthraquinone structure to jointly accelerate the cracking of the lignin-cellulose composite structure.

[0018] Based on the above technical solutions, preferably, in step S1, the mass ratio of hexamethylene diisocyanate to iron-based biochar is 1-2:1, and the mass ratio of urea to hexamethylene diisocyanate is 1-1.2:1.

[0019] Based on the above technical solutions, preferably, in step S2, the mass ratio of mercapto trimethoxysilane to carboxymethyl trimethoxysilane is 1:1-3.2, and the mass ratio of the total amount of silane reagents to the acid-treated sepiolite is 0.8-1.2:1.

[0020] More preferably, the acid-treated sepiolite includes: immersing sepiolite in a 2.5-3.5 mol / L hydrochloric acid solution for 3-5 h, then washing to neutrality and drying at 100-120 °C for 4-6 h.

[0021] Based on the above technical solutions, preferably, in step S3, the mass ratio of silanized sepiolite to vinyl anthraquinone is 1:0.3-0.7, the dosage of azobisisobutyronitrile is 0.5-1.5% of the total mass of the reaction mixture, and the vinyl anthraquinone is 2-vinyl anthraquinone.

[0022] Based on the above technical solutions, preferably, in step S4, the mass ratio of modified biochar to modified sepiolite is 1:1-3, the mass ratio of EDC to HOBt is 1.2-1.8:1, and the dosage of EDC is 8-15% of the mass of modified sepiolite.

[0023] In the second aspect, the present invention provides a preparation method of a composite microbial agent for rapid composting and decomposition of livestock and poultry manure and straw cellulose at high temperature, including the following steps: centrifugally collecting the bacterial liquid of each strain according to the mass ratio and mixing to obtain a composite microbial bacterial liquid; mixing the composite microbial bacterial liquid and a bacterial liquid carrier according to a liquid-solid ratio of 15-25 ml:1 g, vacuum impregnating at 25-30 °C for 1-2 h, and drying the impregnated mixture in a vacuum drying oven at 30-35 °C for 8-12 h to obtain the composite microbial agent.

[0024] In the third aspect, the present invention provides an application of a composite microbial agent, and the composite microbial agent is used for rapid composting and decomposition treatment of livestock and poultry manure and straw cellulose at high temperature.

[0025] The composite microbial agent for rapid composting and rapid ripening of livestock and poultry manure and straw cellulose and its preparation method according to the present invention have the following beneficial effects compared with the prior art:

[0026] (1) The composite microbial agent provided by the present invention can quickly raise the temperature of the compost pile to the high-temperature range and maintain it for a sufficient time, effectively killing pathogenic microorganisms; forming a complete material conversion chain, especially efficiently cracking the lignin-cellulose composite structure; the carrier provides a stable living microenvironment for microorganisms through the dual functions of iron catalysis and anthraquinone electron transfer, significantly improving their survival rate and activity under extreme composting conditions, and greatly shortening the composting cycle. Through the synergistic effect of the microbial agent and the carrier, the treatment efficiency of livestock and poultry manure and straw high-temperature composting is significantly improved, the composting cycle is shortened, and at the same time, the temperature of the compost pile can be quickly raised to the high-temperature state and stably maintained, effectively killing pathogenic microorganisms and weed seeds, and solving the technical bottleneck of the slow degradation of the lignin-cellulose composite structure in the traditional composting process;

[0027] (2) The composite microbial system provides a high-temperature environment through the rapid proliferation of Thermophilic Streptomyces carbon monoxide and Bacillus stearothermophilus. Phanerochaete chrysosporium secretes lignin-degrading enzyme systems to crack the lignocellulose structure. Trichoderma viride provides highly active cellulase to convert cellulose into available carbon sources. Bacillus subtilis and Bacillus licheniformis decompose proteins and starches to fix nutrients. Aspergillus niger produces organic acids to promote the dissolution of mineral elements, forming a complete material conversion chain. The various strains form a synergistic effect rather than an antagonistic relationship, making the overall degradation efficiency much higher than the simple superposition effect of a single strain;

[0028] (3) The multi-functional sepiolite carrier introduces mercapto and carboxyl bifunctional groups through silanization, and then covalently grafts the anthraquinone structure onto the surface of sepiolite, promoting electron transfer inside and outside microorganisms, significantly improving the activities of laccase, manganese peroxidase and lignin peroxidase, and synergistically acting with the microbial agent to further promote the improvement of the lignin degradation rate, enabling the difficult-to-degrade components in straw to be efficiently converted and utilized during the composting process;

[0029] (4) Connect the modified biochar with complementary functions tightly to the modified sepiolite to form a three-dimensional network composite carrier with excellent mechanical stability. This carrier not only has a rich pore structure and a large specific surface area, providing an ideal attachment and living microenvironment for microorganisms, but also combines the dual functions of iron-catalyzed oxidation and anthraquinone electron transfer, and can still maintain structural integrity and functional stability in the composting environment, significantly improving the survival rate and metabolic activity of microorganisms in extreme environments, making the composite microbial agent show excellent adaptability and lasting effects in practical applications. Description of the Drawings

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0031] Figure 1 Trend graph of composting temperature changing with time for the examples and comparative examples of the present invention;

[0032] Figure 2 Trend graph of composting pH changing with time for the examples and comparative examples of the present invention;

[0033] Figure 3 Trend graph of composting carbon-nitrogen ratio changing with time for the examples and comparative examples of the present invention;

[0034] Figure 4 Trend graph of composting germination index changing with time for the examples and comparative examples of the present invention. Detailed implementation manners

[0035] The following will combine the implementation manners of the present invention to clearly and completely describe the technical solutions in the implementation manners of the present invention. Obviously, the described implementation manners are only some implementation manners of the present invention, rather than all implementation manners. Based on the implementation manners in the present invention, all other implementation manners obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0036] The bacterial strains used in the embodiments of the present invention are all purchased through regular channels. Among them, the preservation number of Streptomyces thermocarboxydus is CCTCC M 2010026, the preservation number of Bacillus stearothermophilus is CCTCC CB 20081618, the preservation number of Bacillus subtilis is CCTCC AB 130112, the preservation number of Bacillus licheniformis is CCTCC AB 2016133, the preservation number of Phanerochaete chrysosporium is, the preservation number of Aspergillus niger is CCTCC AF 91005, the preservation number of Phanerochaete chrysosporium is CGMCC 5.776, and Trichoderma viride is preserved in the China Center for Type Culture Collection of Agricultural Microorganisms, and the preservation number is: ACCC 30166.

[0037] Sepiolite is purchased from Shanghai Yuanye Bio-Technology Co., Ltd., 200 mesh.

[0038] Example 1

[0039] This embodiment provides a composite microbial agent for rapid composting and ripening of livestock and poultry manure and straw cellulose, and a preparation method thereof. The composite microbial liquid includes: 25 g of Thermophilic Streptomyces carbon monoxide, 22 g of Bacillus stearothermophilus, 20 g of Bacillus subtilis, 14 g of Bacillus licheniformis, 8 g of Phanerochaete chrysosporium, 6 g of Aspergillus niger, and 5 g of Trichoderma viride. Mix the above bacteria in proportion, and adjust the concentration of the bacterial liquid to 10 8 CFU / ml. The composite microbial liquid and the bacterial liquid carrier are mixed according to a liquid-solid ratio of 20 ml:1 g, and vacuum impregnated at 27°C for 1.5 h (vacuum degree is -0.08 MPa). The impregnated mixture is dried in a vacuum drying oven at 30°C for 10 h to obtain a composite microbial agent with a moisture content of less than 10%.

[0040] The preparation method of the bacterial liquid carrier is as follows:

[0041] S1. Crush wheat straw and pass it through a 60-mesh sieve to obtain biomass powder. Immerse 35 g of biomass powder in 60 g of FeSO4·7H2O solution (0.75 mol / L), and add 5 g of hydrogen peroxide solution with a mass percentage of 30%. After mixing and stirring at 27°C for 12 h, dry it in an 80°C oven until constant weight, grind it, and heat it to 320°C at a heating rate of 5°C / min under nitrogen protection, and keep it carbonized for 2.5 h. After natural cooling, wash and dry it to obtain iron-based biochar;

[0042] Disperse 10 g of iron-based biochar in 100 ml of absolute ethanol and ultrasonically disperse it. Add 10 g of hexamethylene diisocyanate, react at 45°C for 2.5 h under nitrogen protection, then add 6 g of hexamethylene diisocyanate, react at 55°C for 2 h, then add 17 g of urea, and react at 70°C for 7 h. After the reaction is completed, filter, wash, and dry to obtain modified biochar;

[0043] S2. Immerse sepiolite in 3.0 mol / L hydrochloric acid solution for 4 h, with a liquid-solid ratio of 10:1, then filter and wash until neutral, dry at 110°C for 5 h, and grind it through a 100-mesh sieve to obtain acid-treated sepiolite. Disperse 10 g of acid-treated sepiolite in 100 ml of water, ultrasonically disperse it, add 4 g of mercapto trimethoxysilane and 6.5 g of carboxymethyl trimethoxysilane, adjust the pH to 5.0 - 5.5, and react at 75°C for 7 h. After the reaction is completed, centrifuge the product, filter, wash, and dry to obtain silanized sepiolite;

[0044] S3. Disperse 10 g of silanized sepiolite and 5 g of 2-vinyl anthraquinone in 200 ml of toluene / ethanol solution (the volume ratio of toluene and ethanol is 4:1). Under nitrogen protection, add 0.165 g of azobisisobutyronitrile and react at 65°C for 6 h. After the reaction is completed, centrifuge the product, filter, wash, and dry to obtain modified sepiolite;

[0045] S4. Disperse 10 g of modified biochar and 20 g of modified sepiolite in 300 ml of anhydrous DMF, ultrasonically disperse, under the protection of nitrogen and in an ice-water bath, add 1.8 g of EDC / HOBt as a condensing agent (the mass ratio of EDC to HOBt is 1.6:1), gradually raise the temperature to room temperature, react for 11 h, after the reaction is completed, centrifuge the product, filter, wash, dry, and finally grind through a 100-mesh sieve to obtain a bacterial liquid carrier.

[0046] Example 2

[0047] This example provides a composite microbial agent for rapid composting and ripening of livestock and poultry manure and straw cellulose at high temperature and its preparation method. The composite microbial liquid includes: 20 g of Thermophilic carbon monoxide streptomyces, 25 g of Bacillus stearothermophilus, 15 g of Bacillus subtilis, 20 g of Bacillus licheniformis, 5 g of Phanerochaete chrysosporium, 5 g of Aspergillus niger, and 10 g of Trichoderma viride. Mix the above bacteria in proportion, adjust the concentration of the bacterial liquid to 10 8 CFU / ml, mix the composite microbial liquid and the bacterial liquid carrier according to the liquid-solid ratio of 15 ml:1 g, impregnate in vacuum at 25 °C for 2 h (vacuum degree is -0.08 MPa), dry the impregnated mixture in a vacuum drying oven at 30 °C for 12 h to obtain a composite microbial agent with a moisture content of less than 10%.

[0048] The preparation method of the bacterial liquid carrier is as follows:

[0049] S1. Crush wheat straw through a 60-mesh sieve to obtain biomass powder. Immerse 20 g of biomass powder in 40 g of FeSO4·7H2O solution (0.7 mol / L), add 1 g of hydrogen peroxide solution with a mass percentage of 25%, mix and stir at 25 °C for 15 h, then dry to constant weight in an 80 °C oven, grind, and heat to 300 °C at a heating rate of 5 °C / min under the protection of nitrogen, keep warm and carbonize for 3 h, naturally cool, and then wash and dry to obtain iron-based biochar;

[0050] Disperse 10 g of iron-based biochar in 100 ml of anhydrous ethanol, ultrasonically disperse, add 6 g of hexamethylene diisocyanate, react at 40 °C for 3 h under the protection of nitrogen, then add 4 g of hexamethylene diisocyanate, react at 50 °C for 2 h, then add 10 g of urea, react at 60 °C for 8 h, after the reaction is completed, filter, wash, and dry to obtain modified biochar;

[0051] S2. Immerse sepiolite in 2.5 mol / L hydrochloric acid solution for 3 h with a liquid-solid ratio of 10:1, then filter and wash until neutral, dry at 100 °C for 6 h, and grind through a 100-mesh sieve to obtain acid-treated sepiolite. Disperse 10 g of acid-treated sepiolite in 100 ml of water, ultrasonically disperse, add 1.9 g of mercapto trimethoxysilane and 6.1 g of carboxymethyl trimethoxysilane, adjust the pH to 5.0 - 5.5, and react at 70 °C for 8 h. After the reaction, centrifuge the product, filter, wash, and dry to obtain silanized sepiolite;

[0052] S3. Disperse 10 g of silanized sepiolite and 3 g of 2-vinyl anthraquinone in 200 ml of toluene / ethanol solution (volume ratio of toluene to ethanol is 4:1). Under nitrogen protection, add 0.065 g of azobisisobutyronitrile and react at 60 °C for 7 h. After the reaction, centrifuge the product, filter, wash, and dry to obtain modified sepiolite;

[0053] S4. Disperse 10 g of modified biochar and 10 g of modified sepiolite in 200 ml of anhydrous DMF, ultrasonically disperse. Under nitrogen protection and in an ice-water bath, add 0.08 g of EDC / HOBt as a condensing agent (mass ratio of EDC to HOBt is 1.2:1), gradually raise the temperature to room temperature, and react for 12 h. After the reaction, centrifuge the product, filter, wash, dry, and finally grind through a 100-mesh sieve to obtain the bacterial liquid carrier.

[0054] Example 3

[0055] This example provides a composite microbial agent for rapid composting and ripening of livestock and poultry manure and straw cellulose at high temperature and its preparation method. The composite microbial liquid includes: 30 g of Thermophilic carbon monoxide streptomyces, 20 g of Bacillus stearothermophilus, 25 g of Bacillus subtilis, 10 g of Bacillus licheniformis, 5 g of Phanerochaete chrysosporium, 5 g of Aspergillus niger, and 5 g of Trichoderma viride. Mix the above bacteria in proportion, adjust the concentration of the bacterial liquid to 10 8 CFU / ml. Mix the composite microbial liquid and the bacterial liquid carrier according to a liquid-solid ratio of 25 ml:1 g, vacuum impregnate at 30 °C for 1 h (vacuum degree is -0.08 MPa), and dry the impregnated mixture in a vacuum drying oven at 35 °C for 8 h to obtain a composite microbial agent with a moisture content lower than 10%.

[0056] The preparation method of the bacterial liquid carrier is as follows:

[0057] S1. Crush wheat straw and sieve it through a 60-mesh sieve to obtain biomass powder. Immerse 50 g of biomass powder in 80 g of FeSO₄·7H₂O solution (0.8 mol / L), add 10 g of hydrogen peroxide solution with a mass percentage of 35%, mix and stir at 30 °C for 10 h, then dry it to constant weight in an 80 °C oven, grind it, and heat it to 350 °C at a heating rate of 5 °C / min under nitrogen protection, keep it for carbonization for 2 h, cool it naturally, wash and dry it to obtain iron-based biochar;

[0058] Disperse 10 g of iron-based biochar in 100 ml of absolute ethanol by ultrasonic dispersion, add 12 g of hexamethylene diisocyanate, react at 50 °C for 2 h under nitrogen protection, then add 8 g of hexamethylene diisocyanate and react at 60 °C for 2 h, then add 24 g of urea and react at 80 °C for 6 h. After the reaction is completed, filter, wash and dry to obtain modified biochar;

[0059] S2. Immerse sepiolite in 3.5 mol / L hydrochloric acid solution for 5 h with a liquid-solid ratio of 10:1, then filter and wash it to neutrality, dry it at 120 °C for 4 h and then grind it through a 100-mesh sieve to obtain acid-treated sepiolite. Disperse 10 g of acid-treated sepiolite in 100 ml of water by ultrasonic dispersion, add 2.8 g of mercapto trimethoxysilane and 9.2 g of carboxymethyl trimethoxysilane, adjust the pH to 5.0 - 5.5, and react at 80 °C for 6 h. After the reaction is completed, centrifuge the product, filter, wash and dry it to obtain silanized sepiolite;

[0060] Disperse 10 g of silanized sepiolite and 7 g of 2-vinyl anthraquinone in 200 ml of toluene / ethanol solution (the volume ratio of toluene to ethanol is 4:1), under nitrogen protection, add 0.255 g of azobisisobutyronitrile, and react at 70 °C for 5 h. After the reaction is completed, centrifuge the product, filter, wash and dry it to obtain modified sepiolite;

[0061] S4. Disperse 10 g of modified biochar and 30 g of modified sepiolite in 400 ml of anhydrous DMF by ultrasonic dispersion. Under nitrogen protection and in an ice-water bath, add 4.5 g of EDC / HOBt as a condensing agent (the mass ratio of EDC to HOBt is 1.8:1), gradually raise the temperature to room temperature, and react for 10 h. After the reaction is completed, centrifuge the product, filter, wash and dry it, and finally grind it through a 100-mesh sieve to obtain the carrier for bacterial liquid.

[0062] Comparative Example 1

[0063] This comparative example provides a composite microbial inoculum for rapid composting and decomposition of livestock and poultry manure and straw cellulose at high temperature and its preparation method. Specifically, it is the same as Example 1, except that Thermophilic carbon monoxide streptomyces is not added to the composite microbial liquid. The composite microbial liquid includes: 25 g of Bacillus stearothermophilus, 20 g of Bacillus subtilis, 14 g of Bacillus licheniformis, 8 g of Phanerochaete chrysosporium, 6 g of Aspergillus niger, and 5 g of Trichoderma viride. Sterile water is added to make up the total mass of the microbial liquid the same as that in Example 1.

[0064] Comparative Example 2

[0065] This comparative example provides a composite microbial inoculum for rapid composting and decomposition of livestock and poultry manure and straw cellulose at high temperature and its preparation method. Specifically, it is the same as Example 1, except that Phanerochaete chrysosporium and Trichoderma viride are not added to the composite microbial liquid. The composite microbial liquid includes:

[0066] 25 g of Thermophilic carbon monoxide streptomyces, 22 g of Bacillus stearothermophilus, 20 g of Bacillus subtilis, 14 g of Bacillus licheniformis, and 5 g of Trichoderma viride. Sterile water is added to make up the total mass of the microbial liquid the same as that in Example 1.

[0067] Comparative Example 3

[0068] This comparative example provides a composite microbial inoculum for rapid composting and decomposition of livestock and poultry manure and straw cellulose at high temperature and its preparation method. Specifically, it is the same as Example 1, except that: in the preparation of the microbial liquid carrier, the biochar is not loaded with iron, that is:

[0069] S1. The wheat straw is crushed and sieved through a 60-mesh sieve to obtain biomass powder. 35 g of the biomass powder is heated to 320 °C at a heating rate of 5 °C / min under nitrogen protection, and carbonized for 2.5 h. After natural cooling, it is washed and dried to obtain biochar. 10 g of the biochar is dispersed in 100 ml of anhydrous ethanol by ultrasonic dispersion, 10 g of hexamethylene diisocyanate is added, and the reaction is carried out at 45 °C for 2.5 h under nitrogen protection. Then, 6 g of hexamethylene diisocyanate is added, and the reaction is carried out at 55 °C for 2 h. Then, 17 g of urea is added, and the reaction is carried out at 70 °C for 7 h. After the reaction is completed, it is filtered, washed, and dried to obtain modified biochar.

[0070] Comparative Example 4

[0071] This comparative example provides a composite microbial inoculum for rapid composting and decomposition of livestock and poultry manure and straw cellulose at high temperature and its preparation method. Specifically, it is the same as Example 1, except that: in the preparation of the microbial liquid carrier, the biochar is not loaded with urea, that is

[0072] S1. Crush wheat straw and sieve it through a 60-mesh sieve to obtain biomass powder. Immerse 35 g of biomass powder in 60 g of FeSO₄·7H₂O solution (0.75 mol / L), add 5 g of 30% hydrogen peroxide solution, mix and stir at 27 °C for 12 h, then dry it to constant weight in an 80 °C oven, grind it, and heat it to 320 °C at a heating rate of 5 °C / min under nitrogen protection, keep it for carbonization for 2.5 h, and after natural cooling, wash and dry it to obtain iron-based biochar;

[0073] S2. Immerse sepiolite in 3.0 mol / L hydrochloric acid solution for 4 h with a liquid-solid ratio of 10:1, then filter and wash it to neutral, dry it at 110 °C for 5 h and then grind it through a 100-mesh sieve to obtain acid-treated sepiolite. Disperse 10 g of acid-treated sepiolite in 100 ml of water, ultrasonically disperse it, add 4 g of mercapto trimethoxysilane and 6.5 g of carboxymethyl trimethoxysilane, adjust the pH to 5.0 - 5.5, react at 75 °C for 7 h. After the reaction, centrifuge the product, filter, wash and dry it to obtain silanized sepiolite;

[0074] S3. Disperse 10 g of silanized sepiolite and 5 g of 2-vinyl anthraquinone in 200 ml of toluene / ethanol solution (the volume ratio of toluene to ethanol is 4:1), under nitrogen protection, add 0.165 g of azobisisobutyronitrile, react at 65 °C for 6 h. After the reaction, centrifuge the product, filter, wash and dry it to obtain modified sepiolite;

[0075] S4. Disperse 10 g of iron-based biochar and 20 g of modified sepiolite in 300 ml of anhydrous DMF, ultrasonically disperse it, stir at room temperature for 11 h. After the reaction, centrifuge the product, filter, wash and dry it, and finally grind it through a 100-mesh sieve to obtain the carrier for bacterial liquid.

[0076] Comparative Example 5

[0077] This comparative example provides a composite bacterial agent for rapid composting and ripening of livestock and poultry manure and straw cellulose at high temperature and its preparation method, which is the same as Example 1 in detail, except that: in the preparation of the carrier for bacterial liquid, sepiolite is not loaded with vinyl anthraquinone, that is

[0078] S2. Immerse sepiolite in 3.0 mol / L hydrochloric acid solution for 4 h with a liquid-solid ratio of 10:1, then filter and wash it to neutral, dry it at 110 °C for 5 h and then grind it through a 100-mesh sieve to obtain acid-treated sepiolite. Disperse 10 g of acid-treated sepiolite in 100 ml of water, ultrasonically disperse it, add 4 g of mercapto trimethoxysilane and 6.5 g of carboxymethyl trimethoxysilane, adjust the pH to 5.0 - 5.5, react at 75 °C for 7 h. After the reaction, centrifuge the product, filter, wash and dry it to obtain silanized sepiolite;

[0079] S3. Disperse 10 g of modified biochar and 20 g of silylated sepiolite in 300 ml of anhydrous DMF, ultrasonically disperse them, and under the protection of nitrogen and in an ice-water bath, add 1.8 g of EDC / HOBt as a condensing agent (the mass ratio of EDC to HOBt is 1.6:1). Gradually raise the temperature to room temperature and react for 11 h. After the reaction, centrifuge the product, filter, wash, dry, and finally grind it through a 100-mesh sieve to obtain the bacterial liquid carrier.

[0080] Performance detection

[0081] Organic raw materials: livestock and poultry manure (such as pig manure) and corn straw. Crush the corn straw to a particle size of about 3 - 5 cm. Mix pig manure and corn straw in a mass ratio of 1:3 as raw materials for composting and decomposition experiments. Ferment the raw materials, adjust the moisture content to 55 - 65%, and the C / N to 20 - 25. Mix the composite bacterial agent and the raw materials for composting and decomposition. The added mass of the composite bacterial agent is 2% of the mass of the raw materials. The composting period is 30 d. Record the temperature every day, turn the pile and sample every 3 d, and detect the temperature, moisture content, pH value, carbon-nitrogen ratio, and germination index of the pile body. After the degradation is completed, detect the relative contents of cellulose and lignin in the corn straw, and calculate the degradation rate based on the relative contents. The detection results are shown in Figures 1-4 and Table 1.

[0082] Table 1 Degradation efficiency of cellulose

[0083]

[0084] From Table 1 and Figures 1-4 it can be seen that through the synergistic effect of the composite bacterial agent and the functionalized carrier, the present invention realizes rapid heating of the pile body, stable maintenance of the high-temperature period, and efficient degradation of cellulose / lignin, significantly improving the composting and decomposition efficiency of livestock and poultry manure and straw. The comparative study shows that the lack of thermophilic bacteria leads to a shortening of the high-temperature stage, and the lack of lignin-degrading bacteria significantly inhibits the decomposition of refractory components; the lack of iron-based catalysis in the carrier weakens the microbial metabolic activity, the lack of urea loading limits the nitrogen source supply, and the lack of vinyl anthraquinone grafting reduces the redox-mediated ability, all of which prolong the composting period and reduce the degradation efficiency. The technical solution of the embodiment of the present invention provides an efficient and stable technical path for the resource utilization of agricultural waste through the synergistic mechanism of complementary functions of bacterial strains and multi-stage modification of the carrier, verifying the core value of the synergistic effect of microorganisms and materials in the composting process.

[0085] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composite microbial inoculum for rapid composting and maturity of livestock and poultry manure and straw cellulose at high temperature, characterized in that, It includes a composite microbial liquid and a liquid carrier. The composite microbial liquid includes Streptomyces thermocarboxydus, Bacillus stearothermophilus, Bacillus subtilis, Bacillus licheniformis, Phanerochaete chrysosporium, Trichoderma viride, and Aspergillus niger. The liquid carrier is obtained by compounding modified biochar and modified sepiolite through an amidation reaction.

2. The composite microbial agent for rapid composting and rapid decomposition of livestock and poultry manure and straw cellulose according to claim 1, characterized in that, The composite microbial liquid, by mass percentage, includes 20 - 30% of Streptomyces thermocarboxydus, 20 - 25% of Bacillus stearothermophilus, 15 - 25% of Bacillus subtilis, 10 - 20% of Bacillus licheniformis, 5 - 10% of Phanerochaete chrysosporium, 5 - 8% of Aspergillus niger, and 5 - 10% of Trichoderma viride.

3. A composite microbial agent for rapid composting and quick decomposition of livestock and poultry manure and straw cellulose as described in claim 1, characterized in that, The preparation method of the liquid carrier includes the following steps: S1. Disperse iron-based biochar in anhydrous ethanol, add hexamethylene diisocyanate, react at 40 - 60 °C for 4 - 5 h, then add urea, and react at 60 - 80 °C for 6 - 8 h to obtain modified biochar. S2. Disperse acid-treated sepiolite in water, add mercapto trimethoxysilane and carboxymethyl trimethoxysilane, and react at 70 - 80 °C for 6 - 8 h to obtain silanized sepiolite. S3. Disperse silanized sepiolite and vinyl anthraquinone in an aqueous DMF solution, add azobisisobutyronitrile, and react at 60 - 70 °C for 5 - 7 h to obtain modified sepiolite. S4. Disperse modified biochar and modified sepiolite in DMF, add EDC / HOBt as a condensing agent, and react at room temperature for 10 - 12 h under nitrogen protection to obtain the liquid carrier.

4. A composite microbial agent for rapid composting and rapid decomposition of livestock and poultry manure and straw cellulose according to claim 1, characterized in that, The preparation method of the iron-based biochar in step S1 includes: impregnate biomass powder in an FeSO4·7H2O solution, add a hydrogen peroxide solution with a mass percentage of 25 - 35%, mix and then dry, and carbonize at 300 - 350 °C to obtain iron-based biochar.

5. A composite microbial agent for rapid composting and maturity of livestock and poultry manure and straw cellulose at high temperature according to claim 1, characterized in that, In step S1, the mass ratio of hexamethylene diisocyanate to iron-based biochar is 1.5 - 2.5:1, and the mass ratio of urea to hexamethylene diisocyanate is 0.4 - 0.65:

1.

6. The composite microbial agent for rapid composting and quick decomposition of livestock and poultry manure and straw cellulose according to claim 1, characterized in that, In step S2, the mass ratio of mercapto trimethoxysilane to carboxymethyl trimethoxysilane is 1:1 - 3.2, and the mass ratio of the total amount of silane reagents to acid-treated sepiolite is 0.8 - 1.2:

1.

7. A composite microbial inoculum for rapid composting and rapid decomposition of livestock and poultry manure and straw cellulose as described in claim 1, characterized in that, In step S3, the mass ratio of silanized sepiolite to vinyl anthraquinone is 1:0.3 - 0.7, and the dosage of azobisisobutyronitrile is 0.5 - 1.5% of the total mass of the reaction mixture.

8. A composite microbial agent for rapid composting and ripening of livestock and poultry manure and straw cellulose as described in claim 1, characterized in that, In step S4, the mass ratio of modified biochar to modified sepiolite is 1:1 - 3, the mass ratio of EDC to HOBt is 1.2 - 1.8:1, and the dosage of EDC is 8 - 15% of the mass of modified sepiolite.

9. The preparation method of a composite microbial inoculum for rapid composting and ripening of livestock and poultry manure and straw cellulose at high temperature according to any one of claims 1-8, characterized in that, It includes the following steps: centrifugally collect the liquid of each strain by mass ratio respectively, and mix to prepare a composite microbial liquid; mix the composite microbial liquid and the liquid carrier according to a liquid-solid ratio of 15 - 25 ml:1 g, vacuum impregnate at 25 - 30 °C for 1 - 2 h, and dry the impregnated mixture in a vacuum drying oven at 30 - 35 °C for 8 - 12 h to obtain a composite microbial agent.

10. Use of the compound microbial agent according to any one of claims 1-8, characterized in that, The composite microbial agent is used for rapid composting and decomposition treatment of livestock and poultry manure and straw cellulose at high temperature.

Images