CN111454994B

CN111454994B - Treatment method of ecological breeding waste

Info

Publication number: CN111454994B
Application number: CN202010234764.2A
Authority: CN
Inventors: 蒋日进; 陈�峰; 王好学; 于春梅
Original assignee: Zhejiang Marine Fisheries Research Institute
Current assignee: Zhejiang Marine Fisheries Research Institute
Priority date: 2020-03-30
Filing date: 2020-03-30
Publication date: 2021-05-11
Anticipated expiration: 2040-03-30
Also published as: CN111454994A

Abstract

The invention provides a method for treating ecological breeding waste, which belongs to the technical field of organic waste resource recycling and comprises the following steps: a solid-liquid separation process for separating the waste material to obtain dry materials and waste liquid; respectively carrying out anaerobic fermentation on the dry materials and the waste liquid to obtain methane, biogas residues and sticky substances; composting treatment process for decomposing the biogas residues and the sticky matters, wherein alpha-naphthylacetic acid and benzylidene acetone are used as gain agents in the composting treatment process; the fermentation process is anaerobic fermentation under the action of low voltage of 0.7-1.0V. The treatment method can shorten the fermentation period and increase the final gas production rate of unit waste; the secretion and activity of cellulase in compost fermentation are improved, the high-temperature duration time of the compost fermentation is prolonged, the decomposition time is shortened, and the total humus content in the product is improved; the effective resource utilization rate of the waste is improved, and the aims of energy conservation, environmental protection, resource utilization of the waste and recycling of biomass energy are fulfilled.

Description

Treatment method of ecological breeding waste

Technical Field

The invention belongs to the technical field of organic waste resource recycling, and particularly relates to a treatment method of ecological breeding waste.

Background

The ecological breeding development is increasingly vigorous at present, the breeding industry is gradually optimized and develops to scale, and certain environmental pollution is caused while the breeding industry is developed. The waste discharge of ecological farms is gradually increased, and according to related investigation, the discharge amount of livestock and poultry manure in 2018 is about 28 hundred million t, which is 2.24 times of the production amount of industrial solid waste, and the rate of the manure discharge permeating into water is about 30%, thus seriously polluting water quality.

The ecological breeding waste comprises green feed, compound feed, excrement, waste water and the like, and a large amount of organic matters, nitrogen, phosphorus and other nutrient substances, pathogenic bacteria and pest eggs are contained in the ecological breeding waste, the untreated breeding waste can generate foul smell when being randomly stacked, and causes breeding bacteria and mosquitoes and flies to flow into nearby basins, and easily enter nearby rivers and basins along with rainstorm or surface runoff to cause eutrophication pollution of water bodies.

In the existing treatment method of the cultivation waste, one scheme is as follows: the culture waste is directly buried, but the scheme has the defects that the culture waste permeates into underground water to cause water body pollution, occupies a landfill site, causes gas pollution and the like. The other scheme is as follows: the cultivation waste is treated by a fermentation process to obtain clean energy, namely methane and organic fertilizer, so that the problem of pollution of the cultivation waste is solved. Although the energy treatment of the cultivation waste is a contract for the development of economy, environment and resources in the world, the cultivation waste can be recycled, so that the problem of non-point source pollution caused by the recycling of the cultivation waste can be solved, a large economic benefit can be generated, and a solution path is provided for the current energy shortage. However, the above-mentioned energy treatment still faces more problems: the fermentation system is started slowly; the processing cycle is too long; the methane production efficiency is very low; the high-content lignocellulose in the excrement of vegetarian animals such as cattle, sheep and geese is difficult to degrade, so that the waste of biomass energy is caused, and the conversion rate of raw materials is low. These problems severely limit further development of energy treatment technology.

Disclosure of Invention

The invention aims to provide a fermentation medium-efficient unit waste material production; the method for treating the ecological breeding waste can improve the secretion and activity of cellulase in compost fermentation, prolong the high-temperature duration time of the compost fermentation, shorten the decomposition time and improve the total humus content in the product, improves the effective resource utilization rate of the waste, and achieves the purposes of energy conservation, environmental protection, resource utilization of the waste and recycling of biomass energy.

The technical scheme adopted by the invention for realizing the purpose is as follows:

the treatment method of the ecological breeding waste comprises the following steps:

a solid-liquid separation process for separating the waste to obtain dry materials and waste liquid;

respectively carrying out anaerobic fermentation on the dry materials and the waste liquid to obtain methane, biogas residues and sticky substances; and the number of the first and second groups,

composting treatment process for decomposing the biogas residues and the sticky matters, wherein alpha-naphthylacetic acid and benzylidene acetone are used as gain agents in the composting treatment process;

the fermentation process is anaerobic fermentation under the action of low voltage, specifically 0.7-1.0V.

The treatment method separates the dry materials and the waste liquid in the cultivation waste in advance, applies external low voltage for separate fermentation, can improve the mass transfer efficiency of a fermentation system, improve the activity of microbial flora in the fermentation system, accelerate the metabolism and the effective degradation rate of the microbial flora, finally shorten the fermentation period, effectively increase the final gas production rate of unit waste and improve the effective recycling utilization rate of the waste compared with the prior art.

In some embodiments, the dry material resulting from the solid-liquid separation has a water content of 35 to 65%. The ecological breeding waste comprises, but is not limited to, waste excretion of breeding animals, dead animal bodies, aquaculture sewage, surface sewage, feed waste and the like, and pollutants such as organic matters, nitrogen, phosphorus and the like which are rich in the ecological breeding waste can be used as raw materials for biogas fermentation for resource recycling, so that the ecological breeding waste has the advantages of energy conservation and environmental protection.

In some embodiments, the dry matter included in the feedstock for dry matter fermentation is dry matter resulting from solid-liquid separation, sludge, and a fermentation agent; the temperature of the dry material fermentation is 30-45 ℃, and the anaerobic fermentation time is 15-40 d; the products of the dry material fermentation are first methane and methane slag.

Preferably, the weight ratio of dry materials to sludge and leavening agent in the dry materials is 4-6:1.5-3:1, and the weight percentage of the dry materials in the fermentation system is 18-30%.

The dead animals, seedlings and the like caused by diseases and the like exist in the ecological breeding process, and are not beneficial to environmental protection when being disposed freely or buried on site, so in some more preferable embodiments, the dry matter of the dry material fermentation system also comprises harmless products obtained after the dead breeding animals are subjected to pressurized hydrothermal treatment, and the weight ratio of the harmless products in the dry matter is not higher than 20-35%. After the dead animals are subjected to pressurized hydrothermal treatment, the dead animals are subjected to anaerobic fermentation, so that the organic matters rich in the dead animals can be reasonably recycled, the gas yield of biogas fermentation is improved, and the nutrient components and the content of compost can be increased.

Preferably, the temperature of the pressurized hydrothermal treatment is 120-150 ℃, the pressure is 400-600KPa, and the time is 30-60 min.

In some embodiments, the feedstock for waste stream fermentation comprises waste stream, comminuted straw, sludge, and a fermentation agent; the fermentation temperature of the waste liquid is 30-45 ℃, and the anaerobic fermentation time is 15-40 d; the products of the waste liquid fermentation are sticky substances and second methane.

Preferably, the addition amount of the crushed straws is 8-15% of the weight of the waste liquid; the weight ratio of the mixture of the waste liquid and the straws to the sludge and the leavening agent is 6-8:2-5: 1.5. On one hand, the temperature loss of pure waste liquid fermentation can be reduced and the heat preservation energy consumption can be reduced by adding the straws into the waste liquid, on the other hand, the gas production can be improved by adding the fermentation raw materials, and simultaneously, the bio-organic fertilizer formed by composting contains cellulose and lignin degradation products, so that the quality of the bio-organic fertilizer is improved.

Further preferably, in the fermentation process of the dry material fermentation and the waste liquid fermentation, the fermentation temperature is controlled to be 35-45 ℃, and the pH of the fermentation system is adjusted to be 6.5-8.0 by soda lime or hydrochloric acid.

In some embodiments, the starter culture comprises Bacillus subtilis, Streptomyces, Actinomycetes, Bacillus subtilis, Streptomyces,Aspergillus niger, Trichoderma reesei, Pseudomonas sp, and the concentration of each thallus in the starter is 5 × 10⁹-5×10¹⁰cfu/mL, the weight ratio of cfu/mL is 2-3:1-2:1-3:1-3:1: 1-2. The composite microorganisms in the leavening agent have different metabolic performance characteristics under the condition of fermentation environment, can play a role of mutual promotion, and can assist anaerobic fermentation to degrade various organic matter components in the waste material so as to obtain higher gas production efficiency.

In some embodiments, the step of composting is: mixing the fermented biogas residues with the sticky substances, adding zeolite as a leavening agent, and performing composting for 25-50d while turning over for 2-3 times to obtain decomposed bio-organic fertilizer.

Preferably, the zeolite particles have a diameter of 0.1-1.5mm and are added in an amount of 15-25% by weight based on the total weight of the composting system. The microporous structure of the zeolite is favorable for the growth of microorganisms, and can adsorb humus in materials, promote the humification and polymerization of compost, and is favorable for the decomposition and the quality improvement of the materials.

In the composting step, water participates in metabolism of microorganisms and adjusts the composting temperature, and in some more preferable embodiments, the water in the materials is supplemented to the water content of 50-65% in the initial composting period, and the water is supplemented to the water content of 40-60% in each turning.

More preferably, the water added to the composting process contains 0.03-0.08wt% of alpha-naphthylacetic acid and 0.01-0.05wt% of benzalacetone as the gaining agent. The compost raw materials contain cellulose lignin which is difficult to degrade and the like, so that the humification process is influenced, and biomass energy waste is further caused, alpha-naphthylacetic acid and benzalacetone which are supplemented with water can promote microorganisms in the compost body to degrade easily degradable organic matters in the early stage of composting, so that the temperature of the compost body reaches a peak value more quickly, the fermentation microorganisms are converted from thermophilic microorganisms into thermophilic microorganisms, thermophilic actinomycetes are favorable for propagating and secreting more cellulase, the heat released by degradation of the organic matters is increased, the activity of the cellulase is increased in virtuous cycle, and the degradation of the cellulose lignin is accelerated; when the degradation of the refractory organic matters is mainly performed in the later stage of the compost, the circulation of enhancing the activity of the cellulase to accelerate the degradation and the degradation heat release to improve the activity and the secretion of the cellulase can be shown, so that the high-temperature duration in the composting process is prolonged by 20-35%, the decomposing time is effectively shortened by 10-20%, the time cost is saved, the total humic substance content in the product can be improved by degrading the refractory organic matters such as cellulose, and the quality of the compost product and the conversion rate of raw materials are further improved.

In some embodiments, the treated products of the ecological breeding waste can be recycled, such as the biological organic fertilizer obtained by composting can be directly applied to plants in a plant planting area; the first biogas and the second biogas obtained by fermentation can be used for energy supply in an ecological breeding system, such as power generation, heat value supply by combustion and the like, and can also be used for pressurized hydrothermal treatment of dead breeding animals so as to achieve the purpose of reducing power consumption and economic consumption.

The invention has the beneficial effects that:

1) according to the invention, the ecological breeding waste is subjected to resource recycling treatment, the waste is converted into clean energy, namely methane, through the cooperation of external voltage and anaerobic fermentation for efficient utilization, the mass transfer efficiency of a fermentation system is improved, the activity of microbial flora in the fermentation system is improved, the metabolism and the effective degradation rate are accelerated, the fermentation period is finally shortened, the final gas yield of unit waste is effectively increased, and the effective resource utilization rate of the waste is improved; 2) according to the invention, the secretion and activity of microbial metabolite cellulase in composting fermentation are improved, so that the duration time of high temperature of composting fermentation is prolonged, the rotten time is shortened, and refractory organic matters such as cellulose and the like are degraded to improve the total humus content in the product, so that the quality and the raw material conversion rate of the composting product are improved, the organic biological fertilizer is more beneficial to plant absorption and natural degradation, and the low conversion rate of raw materials and the waste of biomass energy caused by the refractory degradation of lignocellulose in the prior art are improved; 3) the treatment method effectively prevents and reduces environmental pollution, is beneficial to relieving the current situation of environmental pressure and energy shortage, and has the beneficial effects of energy conservation, environmental protection, waste resource utilization and biomass energy reutilization; 4) the treatment method achieves harmless treatment, functionalization and resource utilization of the breeding waste, can be popularized and applied to the breeding waste treatment of all breeding industries such as livestock, cattle, sheep, aquatic products and the like, and meets the national aim of waste treatment industrialization.

The invention adopts the technical scheme to provide the treatment method of the ecological breeding waste, makes up the defects of the prior art, and has reasonable design and convenient operation.

Drawings

FIG. 1 is a schematic diagram showing the change in cellulase activity in a pile during composting in test example 1;

FIG. 2 is a schematic diagram showing the change in the total humic substance content in the heap during composting in test example 1;

FIG. 3 is a graph showing the change in the in-pile colonization index HI during composting in Experimental example 1;

FIG. 4 is a graph showing the change in the organic acid content of the microbial metabolites during anaerobic fermentation, A-example 3, B-example 5, C-comparative example 3, D-comparative example 4.

Detailed Description

The technical solution of the present invention is further described in detail below with reference to the following detailed description and the accompanying drawings:

Preferably, the weight ratio of dry materials to sludge and leavening agent in the dry materials is 4-6:1.5-3:1, and the weight percentage of the dry materials in the fermentation system is 18-30%. Specifically, the balance of the fermentation system is supplemented with water except dry matters, and the water is clean tap water instead of culture sewage and the like.

In some embodiments, the starter culture comprises Bacillus subtilis, Streptomyces, Actinomycetes, Aspergillus niger, Trichoderma reesei, and Pseudomonas sp, wherein the concentration of each strain in the starter culture is 5 × 10⁹-5×10¹⁰cfu/mL, the weight ratio of cfu/mL is 2-3:1-2:1-3:1-3:1: 1-2. The composite microorganisms in the leavening agent have different metabolic performance characteristics under the condition of fermentation environment, can play a role of mutual promotion, and can assist anaerobic fermentation to degrade various organic matter components in the waste material so as to obtain higher gas production efficiency.

In other preferred embodiments, the leavening agent further comprises a fermentation catalyst in an amount of 0.1-0.5% by weight, the fermentation catalyst comprises 2-5:1 by weight of dimethylcoumarone and ferric triacetylacetonate, the presence of the fermentation catalyst can shorten the microbial regulation period in fermentation, and simultaneously, the microbial decomposition and utilization efficiency of each raw material is remarkably improved, the accumulation of important intermediate metabolites, namely organic acid, especially acetic acid, is increased, the methane production period is advanced, the problem of slow fermentation start is solved, the efficient production of methane by methanogens is facilitated, and the yield and production efficiency of the fermentation product, namely methane, are remarkably improved.

In some embodiments, the step of composting is: mixing the fermented biogas residues with the sticky substances, adding zeolite as a leavening agent, and performing composting for 25-50d while turning over for 2-3 times to obtain decomposed bio-organic fertilizer. The specific process is as follows: and (3) when the temperature of the compost is obviously reduced each time, performing pile turning treatment, repeating for 2-3 times until the temperature of the compost is close to or slightly higher than the room temperature and no peculiar smell exists, indicating that the compost is completely decomposed to obtain the biological organic fertilizer, and storing for later use.

More preferably, the water added to the composting process contains 0.03-0.08wt% of alpha-naphthylacetic acid and 0.01-0.05wt% of benzalacetone as the gaining agent. The compost raw materials contain cellulose lignin which is difficult to degrade and the like, so that the humification process is influenced, and biomass energy waste is further caused, alpha-naphthylacetic acid and benzalacetone which are supplemented with water can promote microorganisms in the compost body to degrade easily degradable organic matters in the early stage of composting, so that the temperature of the compost body reaches a peak value more quickly, the fermentation microorganisms are converted from thermophilic microorganisms into thermophilic microorganisms, thermophilic actinomycetes are favorable for propagating and secreting more cellulase, the heat released by degradation of the organic matters is increased, the activity of the cellulase is increased in virtuous cycle, and the degradation of the cellulose lignin is accelerated; when the degradation of the refractory organic matters is mainly performed in the later stage of the compost, the circulation of enhancing the activity of the cellulase to accelerate the degradation and the degradation heat release to improve the activity and the secretion of the cellulase can be shown, so that the high-temperature duration in the composting process is prolonged by 20-35%, the decomposing time is effectively shortened by 10-20%, the time cost is saved, the total humic substance content in the product can be improved by degrading the refractory organic matters such as cellulose, and the quality of the compost product and the conversion rate of raw materials can be improved.

The bacillus subtilis, the streptomyces, the actinomycetes, the aspergillus niger, the trichoderma reesei and the pseudomonas are all conventional strains, and can be purchased from the market or from the China general microbiological culture Collection center (CGMCC) and the China Center for Type Culture Collection (CCTCC). In the examples of the present invention, Bacillus subtilis was purchased from Yufeng Biotechnology Co., Ltd, Streptomyces microflavus was purchased from Yufeng Biotechnology Co., Ltd, Actinomycetes was purchased from Yu-nan-sourced beginning Biotechnology Co., Ltd, Aspergillus niger was purchased from Changtai Biotechnology Co., Ltd, Trichoderma reesei was purchased from Yiyi-sourced Congyuan Biotechnology Co., Ltd, and Pseudomonas aeruginosa was purchased from Yu-jing-yu Biotechnology Co., Ltd.

It should be noted that, for other non-described contents/methods in the present invention and embodiments, reference may be made to the conventional technologies known by those skilled in the art, and they will not be described in detail herein.

It is to be understood that the foregoing description is to be considered illustrative or exemplary and not restrictive, and that changes and modifications may be made by those skilled in the art within the scope and spirit of the appended claims. In particular, the present invention covers other embodiments having any combination of features from the different embodiments described above and below, without the scope of the invention being limited to the specific examples below.

Example 1:

the treatment method of the ecological breeding waste specifically comprises the following steps:

(1) solid-liquid separation: standing the cultivation waste of an ecological beef cattle cultivation farm for 4 hours, and filtering the waste by using a grating to separate the waste into dry materials and waste liquid, wherein the water content of the dry materials is controlled to be 55%;

(2) preparing a leavening agent:activating the strains of bacillus subtilis, streptomycete, actinomycete, aspergillus niger, trichoderma reesei and pseudomonas by a conventional method, and performing amplification culture until the concentration of each strain is 5 multiplied by 10⁹-5×10¹⁰cfu/mL, centrifuging and collecting thalli, and mixing the thalli according to the weight ratio of 2.5:1:2.5:1.5:3:1:2 to obtain a leavening agent;

(3) fermenting the dry materials: mixing the separated dry material, sludge and a fermenting agent according to the weight ratio of 5:2.5:1, adjusting the pH value of a fermentation system to 7.5, performing anaerobic fermentation at the temperature of 40 ℃ for 30d to form first methane and biogas residues, collecting the first methane and the biogas residues for later use, wherein the dry material formed by the dry material, the sludge and the fermenting agent accounts for 12% by weight in the fermentation system, and the balance is tap water;

(4) waste liquid fermentation: uniformly mixing the waste liquid obtained by separation with crushed straws, then adding sludge and a leavening agent into the mixture, adjusting the pH value of a fermentation system to 7.5, carrying out anaerobic fermentation at the temperature of 40 ℃ for 20 days to form a sticky substance and second biogas, and collecting the sticky substance and the second biogas for later use, wherein the addition amount of the crushed straws is 15% of the weight of the waste liquid, and the weight ratio of the mixture of the waste liquid and the straws to the sludge to the leavening agent is 7.5:4: 1.5;

(5) composting treatment: mixing the fermented biogas residues and sticky substances, adding 17.5% of zeolite which accounts for the total weight of a compost system and has a particle diameter of 0.1-1.5mm as a swelling agent, performing composting treatment, supplementing water in the materials to a water content of 60% at the initial stage of composting, performing pile turning treatment when the temperature of the compost is obviously reduced every time, supplementing water to a water content of 45% during pile turning each time, repeating for 2 times until the temperature of the compost is close to or slightly higher than room temperature and no odor exists, indicating that the compost is completely decomposed, and storing the decomposed bio-organic fertilizer for later use; the composting treatment starts from the 4 th day to reach the temperature of more than 55 ℃, reaches the highest temperature of 64.3 ℃ for the first time at the 6 th day, reaches the highest temperature of 58.2 ℃ for the second time at the 17 th day, reaches the highest temperature of 45.3 ℃ for the third time at the 24 th day, lasts for 10 days at the temperature of more than 55 ℃, and the complete composting time is 35 days;

(6) and (3) resource utilization of products: the decomposed bio-organic fertilizer can be directly applied to plants in a plant planting area, and the first methane and the second methane can be used for energy supply in an ecological breeding system, such as power generation, combustion for providing heat value and the like, and can also be used for harmless treatment of dead breeding animals.

Example 2:

the method for treating the ecological breeding waste repeats the steps in the example 1, and only differs from the following steps:

when the dry material fermentation and the waste liquid fermentation are carried out in the steps (3) and (4), the anaerobic fermentation is carried out under the action of an additional low voltage, and the additional low voltage is specifically 0.9V;

and (5) the composting treatment reaches the temperature of more than 55 ℃ from the 4 th day, reaches the highest temperature of 63.2 ℃ for the first time at the 7 th day, reaches the highest temperature of 57.8 ℃ for the second time at the 18 th day, reaches the highest temperature of 46.4 ℃ for the third time at the 23 th day, and has the duration time of more than 55 ℃ for 9 days in total, and the complete composting time is 36 days.

Example 3:

the method for treating the ecological breeding waste repeats the steps in the example 2, and only differs from the following steps:

in the step (3), dry matters used in the dry material fermentation process also comprise harmless products obtained by carrying out pressurized hydrothermal treatment on the dead cultured animals, and the specific pressurized hydrothermal treatment step comprises the following steps: crushing the dead cultured animals, and then treating for 60min in an environment with the temperature of 130 ℃ and the pressure of 400KPa to obtain harmless products, wherein the weight ratio of the harmless products in dry substances is 25%;

in the composting treatment of the step (5), the temperature reaches more than 55 ℃ from the 4 th day, the highest temperature reaches 62.8 ℃ for the first time at the 6 th day, the highest temperature reaches 57.1 ℃ for the second time at the 17 th day, the highest temperature reaches 44.5 ℃ for the third time at the 24 th day, the duration time of the period of the temperature is more than 55 ℃ totals 10 days, and the complete composting time is 34.5 days.

Example 4:

the method for treating the ecological breeding waste repeats the steps in the embodiment 3, and only differs from the following steps:

the water supplemented in the composting treatment in the step (5) contains 0.06 wt% of alpha-naphthylacetic acid and 0.04 wt% of benzalacetone as the gain agents, and the gain agents play a role in promoting the degradation process of lignocellulose under the method, so that the degradation of organic matters such as cellulose which are difficult to degrade can be accelerated in the later period of the composting, the temperature of the compost is higher than that of the compost without the gain agents in the later period of the composting, particularly after the composting is turned for the second time, the degradation of the organic matters is more thorough, the high-temperature duration time is prolonged in the whole composting treatment step, the rotting time is shortened, the time cost is saved, and the concrete expression is that: the temperature reaches more than 55 ℃ from the 3 rd, the highest temperature reaches 66.3 ℃ for the first time at the 5 th, the highest temperature reaches 60.3 ℃ for the second time at the 15 th, the highest temperature reaches 50.3 ℃ for the third time at the 21 st, the duration time of the period of the temperature is more than 55 ℃ totals 13 days, and the complete decomposition time of the compost is 30 days.

Example 5:

the method for treating the ecological breeding waste repeats the steps in the example 4, and only differs from the following steps:

in the preparation of the fermenting agent in the step (2), a fermenting catalyst with the weight ratio of 0.5 percent is also added into the fermenting agent, and the fermenting catalyst contains dimethylcoumarone and ferric triacetylacetone with the weight ratio of 3.5: 1;

in the composting treatment of the step (5), the temperature reaches more than 55 ℃ from the 3 rd, the highest temperature reaches 65.7 ℃ for the first time at the 5 th, the highest temperature reaches 60.7 ℃ for the second time at the 16 th, the highest temperature reaches 50.7 ℃ for the third time at the 20 th, the duration time of the period of the temperature of more than 55 ℃ is 13 days in total, and the complete composting time is 29 days.

Example 6:

the breeding waste in the step (1) is sourced from ecological breeding poultry farms.

Comparative example 1:

the gaining agent in the water added in the composting treatment in the step (5) only contains alpha-naphthylacetic acid and is not added with benzalacetone; the composting temperature reaches more than 55 ℃ from the 4 th day, the highest temperature reaches 62.7 ℃ for the first time at the 7 th day, the highest temperature reaches 56.2 ℃ for the second time at the 15 th day, the highest temperature reaches 42.7 ℃ for the third time at the 20 th day, the duration time of the period temperature is more than 55 ℃ totals 8 days, and the complete decomposition time of the compost is 38 days.

Comparative example 2:

the gaining agent in the water added in the composting treatment in the step (5) only contains benzalacetone, and no alpha-naphthylacetic acid is added; the composting temperature reaches more than 55 ℃ from the 5 th day, the highest temperature reaches 63.7 ℃ for the first time at the 8 th day, the highest temperature reaches 57.8 ℃ for the second time at the 19 th day, the highest temperature reaches 44.7 ℃ for the third time at the 25 th day, the duration time of the period temperature is more than 55 ℃ totals 10 days, and the complete decomposition time of the compost is 37 days.

Comparative example 3:

the method for treating the ecological breeding waste repeats the steps in the example 5, and only differs from the following steps:

in the step (2), the fermentation catalyst in the preparation of the leavening agent is dimethyl coumarone, and triacetyl acetone iron is not added.

Comparative example 4:

and (3) in the step (2), a fermentation catalyst in the preparation of the leavening agent is ferric triacetylacetone, and the dimethyl coumarone is not added.

Test example 1:

compost-treated material conversion and enzyme activity testing

The test samples were: composting materials in the composting steps of examples 3 and 4, comparative examples 1 and 2. The sampling method is a multipoint mixing method, samples with the same amount are respectively taken from the upper layer, the middle layer and the lower layer of the pile body, the samples are uniformly mixed, then the mixture is placed into a fume hood for air drying, ground and sieved by a 100-mesh sieve, and the air-dried sample is prepared and then measured.

(1) Enzyme activity test: the determination is carried out by adopting a nitro salicylic acid colorimetric method. A certain amount of the air-dried sample was weighed and sieved through a 1mm sieve, 0.5g was weighed and placed in a 150ml Erlenmeyer flask, and 20ml of a sodium carboxymethylcellulose solution (1%), 5ml of a borate buffer (pH 5.3-5.6) and 1.5ml of toluene were added. Placing the mixture in an incubator at the temperature of 38 ℃ and keeping the temperature for 72 hours. After completion, the filtrate was filtered, and the volume of the filtrate was adjusted to 25ml, and 1ml of the liquid was taken and subjected to an absorbance (wavelength: 540mm) in which the cellulase activity was expressed in mg of glucose produced in 1g of compost sample cultured for 72 hours. The results are shown in FIG. 1.

FIG. 1 is a schematic diagram showing the change of cellulase activity in a compost body during composting. As can be seen from the graph, the cellulase activity was highest in the high temperature period, decreased with decreasing temperature of the compost, and increased with increasing temperature after turning over the compost, particularly after the second turning over, the temperature of the compost in example 4 was high, and the cellulase activity was higher than that of the other groups, and at the end of composting, the cellulase activity in example 4 was 0.35 mg. d^-1·d^-1Example 3 is 0.28 mg. d^-1·d^-1Comparative example 1 is 0.27 mg. d^-1·d^-1Comparative example 2 is 0.26 mg. d^-1·d^-1The additive of the gain agent in the example 4 shows a synergistic gain effect on the conversion of the compost material, so that the compost can show a virtuous cycle of enhancing the activity of the cellulase to accelerate degradation and release heat to improve the activity and secretion of the cellulase, fully degrade lignocellulose and the like which are difficult to degrade in the material, and improve the maturity degree of the compost and the quality of the compost product.

(2) And (3) humus test: weighing 0.5g of sample, placing the sample into a conical flask with the volume of 300ml, adding 50ml of mixed solution (0.1 mol/L) of sodium pyroborate and NaOH, sealing, oscillating, standing for 9H, filtering, sucking 5ml of filtered liquid, placing the filtered liquid into a conical flask with the volume of 150ml, evaporating the liquid in a water bath, and then adding 5ml of 0.8mol/L potassium dichromate solution and 5ml of concentrated H₂SO₄The spout is sealed. And then placing the reagent bottle into a water bath and heating for 15min, adding 50ml of distilled water for constant volume after the reagent tube is cooled to room temperature, then adding 3 drops of an o-phenanthroline indicator, titrating with 0.1mol/L ferrous sulfate until the solution is from yellow green to brick red, and recording the dosage of the ferrous sulfate. The results are shown in FIGS. 2 and 3.

FIG. 2 is a schematic diagram showing the change of the total humus content in the compost during composting. FIG. 3 is a schematic diagram showing the change in humification index HI in a heap during composting.

The total humus is mainly composed of humic acid HA and fulvic acid FA. The humification index HI is the ratio of HA/FA. As can be seen from FIGS. 2 and 3, both the total humus and the humification index tend to decrease and then increase. The total humus content and the humification index of example 4 are highest, the total humus content and the humification index of comparative example 2 are the same, the difference between example 3 and comparative example 1 is not significant, and the total humus content and the humification index are the lowest, which indicates that the humification degree of the compost body of example 4 is the highest at the end of composting, the material degradation rate and the conversion rate in the compost body are the highest, and the quality of the compost product is the best; through comparison, the addition of the gain agent in example 4 shows a synergistic gain effect on the humification degree of the composting step, and can obviously improve the quality of compost products and the conversion rate of raw materials.

Test example 2:

anaerobic fermentation system substance conversion and metabolite testing

The test method comprises the following steps: the dry material fermentation and the waste liquid fermentation are carried out according to the treatment methods of examples 1, 2, 3 and 5 and comparative examples 3 and 4, the time of entering a gas production period after the fermentation is started and the collection amount of the first biogas and the second biogas are recorded, and the organic acid content of the metabolites in the fermentation system is measured by gas chromatography, wherein acetic acid is taken as a main target substance. The measurement results are shown in fig. 4 and table 1.

FIG. 4 is a graph showing the change in the organic acid content of the microbial metabolites during anaerobic fermentation, A-example 3, B-example 5, C-comparative example 3, D-comparative example 4. As can be seen from the figure, the content of organic acid in the fermentation system of example 5 is the highest through comparison, wherein acetic acid accounts for more than 75% of the total content of organic acid; the difference between the example 3 and the comparative example 3 is not obvious, and the organic acid content in the fermentation system of the comparative example 4 is the lowest; by combining the above-mentioned performances, it is demonstrated that the fermentation catalyst added in example 5 can exert a synergistic beneficial effect, so that the activity of microorganisms and the conversion rate of raw materials in the fermentation process are improved, the accumulation of the metabolic products organic acid and acetic acid is significantly increased, the acetic acid is further decomposed to form methane, and the gas yield of the fermentation product biogas and the methane ratio are significantly increased.

TABLE 1 statistics of gas production for anaerobic fermentation systems

As can be seen from the above table, the comparison between examples 1 and 2 shows that the application of low voltage during anaerobic fermentation can promote the fermentation, which is beneficial to increase the gas production; the harmless products of the dead cultured animals added in the dry material fermentation in the embodiment 3 are beneficial to the resource utilization of wastes, and the gas production rate is obviously improved; example 5 enters the gas production period at the earliest, the unit gas production rate is the largest, the occupation ratio of methane in the methane is also the largest, and comparative examples 3 and 4 have different promotion and reduction degrees compared with example 3, but the overall difference is not obvious; it can be known comprehensively that the treatment method of example 5, especially the addition of the fermentation catalyst, can promote the metabolism of microorganisms in the fermentation system, advance the methane production period, improve the problem of slow fermentation start, and significantly improve the yield of the fermentation product biogas and the raw material conversion rate.

Conventional techniques in the above embodiments are known to those skilled in the art, and therefore, will not be described in detail herein.

The above embodiments are merely illustrative, and not restrictive, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention, and the protection scope of the present invention should be defined by the claims.

Claims

1. The treatment method of the ecological breeding waste comprises the following steps:

a solid-liquid separation process for separating the waste material to obtain a dry material and a waste liquid;

respectively carrying out anaerobic fermentation on the dry materials and the waste liquid, and obtaining methane, biogas residues and sticky substances; and the number of the first and second groups,

performing a composting treatment process for decomposing the biogas residues and the sticky matters, wherein alpha-naphthylacetic acid and benzylidene acetone are used as gain agents in the composting treatment process;

the fermentation process is anaerobic fermentation under the action of an additional low voltage, and the additional low voltage is specifically 0.7-1.0V;

the dry matter contained in the raw material for fermenting the dry material is the dry material obtained by solid-liquid separation, sludge and a leavening agent; the temperature of the dry material fermentation is 30-45 ℃, and the anaerobic fermentation time is 15-40 d; the product of the dry material fermentation is first methane and methane slag;

the dry matter of the dry material fermentation system also comprises a harmless product obtained by carrying out pressurized hydrothermal treatment on dead farmed animals, and the weight ratio of the harmless product in the dry matter is not higher than 20-35%;

the raw materials for fermenting the waste liquid comprise the waste liquid, crushed straws, sludge and a leavening agent; the fermentation temperature of the waste liquid is 30-45 ℃, and the anaerobic fermentation time is 15-40 d; the product of the waste liquid fermentation is sticky matter and second methane;

the starter comprises bacillus subtilis, streptomycete, actinomycetes, aspergillus niger, trichoderma reesei and pseudomonas, and the concentration of each thallus in the starter is 5 multiplied by 10⁹-5×10¹⁰cfu/mL, the weight ratio of cfu/mL is 2-3:1-2:1-3:1-3:1: 1-2;

supplementing water in the materials to the water content of 50-65% at the initial stage of composting treatment, and supplementing water to the water content of 40-60% each time the compost is turned; the added water contains 0.03-0.08wt% of alpha-naphthylacetic acid and 0.01-0.05wt% of benzalacetone as the gain agent.

2. The method for treating ecological breeding waste as claimed in claim 1, wherein: the weight ratio of the dry materials to the sludge and the leavening agent in the dry materials is 4-6:1.5-3:1, and the weight percentage of the dry materials in the fermentation system is 18-30%.

3. The method for treating ecological breeding waste as claimed in claim 1, wherein: the temperature of the pressurized hydrothermal treatment is 120-150 ℃, the pressure is 400-600KPa, and the time is 30-60 min.

4. The method for treating ecological breeding waste as claimed in claim 1, wherein: the adding amount of the crushed straws is 8-15% of the weight of the waste liquid; the weight ratio of the mixture of the waste liquid and the straws to the sludge to the leavening agent is 6-8:2-5: 1.5.

5. The method for treating ecological breeding waste as claimed in claim 1, wherein: the composting treatment comprises the following steps: mixing the fermented biogas residues with the sticky substances, adding zeolite as a leavening agent, and performing composting for 25-50d while turning over for 2-3 times to obtain decomposed bio-organic fertilizer.

6. The method for treating ecological breeding waste as claimed in claim 5, wherein: the diameter of the zeolite particles is 0.1-1.5mm, and the addition amount of the zeolite particles is 15-25% of the total weight of the composting system.

7. The method for treating ecological breeding waste as claimed in claim 1, wherein: the leavening agent also contains a leavening catalyst with the weight ratio of 0.1-0.5%, and the leavening catalyst contains dimethylcoumarone and ferric triacetylacetone with the weight ratio of 2-5:1.