Method for promoting corn straw compost heat production by using exogenous microbial agent

Abstract

The invention relates to the technical field of microbial agents, in particular to a method for promoting corn straw composting heat production by utilizing an exogenous microbial agent, which comprises the following steps: crushing corn straws, and mixing with chicken manure to obtain a fermentation raw material; laying a first layer of fermentation raw materials on the waterproof bottom film in the fermentation pit, uniformly scattering mixed freeze-dried powder of bacillus cereus, bacillus smith, bacillus thermophilic denitrification soil bacillus, bacillus licheniformis and ureibacillus thermophilus, laying a second layer of fermentation raw materials, and uniformly scattering EM (effective microorganisms) freeze-dried powder; after a third layer of fermentation raw materials is laid, white rot fungi, chaetomium, trichoderma harzianum and aspergillus niger mixed freeze-dried powder is evenly scattered, and after each layer of fermentation raw materials is laid, water is sprayed to adjust the water content; a heat exchange pipeline is laid between the two layers of fermentation materials, air is inflated into the pipeline through an air blower in the fermentation process, the oxygen content is adjusted to be 5%-15%, and high heat yield and efficient degradation of lignin and cellulose are achieved through functional flora construction.

Description

Technical Field

[0001] The invention relates to the technical field of microbial agents, and in particular to a method for promoting heat generation by corn straw composting by utilizing exogenous microbial agents. Background Art

[0002] Corn straw energy conversion currently primarily involves rapid energy release through thermochemical and biomass conversion, but this has drawbacks such as high equipment investment, pollutant generation, and complex treatment processes. Aerobic fermentation heat production technology has attracted considerable attention due to its simplicity and low cost, but its inherent drawbacks severely hinder its practical application: (1) Insufficient heat generation speed: It usually takes more than 72 hours to enter the high temperature period (>50℃), resulting in delayed heat energy release; (2) Poor temperature continuity: The temperature of the pile fluctuates greatly, the high temperature period (≥50℃) is maintained for a short time, and there is a lack of systematic design for heat energy collection, resulting in a low actual utilization rate.

[0003] In recent years, exogenous bacterial inoculants have been introduced to accelerate the fermentation process. However, current inoculant combinations are primarily focused on organic matter degradation, lacking targeted regulation of heat-producing microbial communities, resulting in "warmth without heat" in energy conversion. While composite inoculants shorten the heating time, they fail to establish metabolic pathways to enhance heat production, and the heat output density of the pile remains insufficient to support the actual heating load.

[0004] Therefore, there is an urgent need for an efficient corn straw fermentation heat production technology that can synergistically optimize microbial metabolic pathways, enhance thermal energy conversion and adapt to low-temperature environments, so as to break through the multiple barriers of existing processes in terms of heat production rate, temperature stability and thermal energy utilization rate, and truly realize the clean energy utilization of corn straw. Summary of the Invention

[0005] The present invention provides a method for promoting heat production by corn straw composting by utilizing exogenous microbial agents, which realizes high heat production and efficient degradation of lignin and cellulose through the construction of functional microbial communities.

[0006] The technical means for achieving the purpose of the present invention are: A method for promoting heat generation by corn straw composting using exogenous microbial agents comprises the following steps: Step 1: crushing corn stalks and mixing them with chicken manure to obtain a fermentation raw material, wherein the C / N ratio of the fermentation raw material is 25-30:1; the crushed corn stalks have a length of 5-30 cm and a thickness of 1-2 cm; Step 2: Lay a waterproof base film with a thickness of 0.2-0.5mm in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.33-0.5×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.33-0.5×10 8 CFU / g fermentation raw material; Thermophilic denitrifying soil Bacillus is 0.33-0.5×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.33-0.45×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus is 0.4-0.5×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.33-0.5×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.33-0.4 8 ×10 8 CFU / g fermentation raw material; Chaetomium is 0.33-0.5×10 8 CFU / g fermentation raw material; Trichoderma harzianum is 0.33-0.4×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.33-0.5×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The moisture content of the first layer is 40%, the moisture content of the second layer is 50%, and the moisture content of the third layer is 55%.

[0007] Step 3: Lay heat exchange pipes between the two layers of fermentation materials. The pipe spacing is 60-80cm. A serpentine layout is adopted. The total length of each layer of heat exchange pipes is 1-50m / m. 2 Fermentation raw materials.

[0008] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the pile to 5-15%.

[0009] As a more optimal technical solution of the present invention: the thickness of each layer of fermentation raw materials is 0.8-1m, the total height of the pile is 2.8-3m, the width is 5-6m, and the length is 11-12m.

[0010] As a more optimal technical solution of the present invention: the heat exchange pipe is made of PE material.

[0011] As a more optimal technical solution of the present invention: the outer layer of the pile is covered with a polyethylene insulation film with a thickness of 0.5 mm, and the inner layer is covered with an aluminum foil reflective layer to reduce heat loss.

[0012] Beneficial effects: The method provided by the present invention significantly improves composting efficiency. Through the targeted combination of the bottom-layer thermophilic bacteria, Examples 1-5 achieved heat production of 3800 to 3951 MJ per ton of raw material, representing a 30% increase over the comparative Example 9. The synergistic effect of the layered inoculants—heat release by the bottom-layer thermophilic bacteria, carbon supply by the middle-layer EM bacteria, and lignin degradation by the top-layer fungi—extends the high-temperature period by 40% and significantly enhances the stability of heat output. This achieves a simultaneous leap in composting efficiency, energy conversion rate, and environmental benefits, providing an industrialized path for the clean energy conversion of corn straw. DETAILED DESCRIPTION

[0013] The present invention is further described in detail below with reference to specific embodiments.

[0014] The present invention is further described below by means of specific examples. Unless otherwise specified, the following raw materials are commercially available. The beneficial effects of the present invention are illustrated in conjunction with practice. However, these embodiments are only used to illustrate the features and advantages of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

[0015] The experimental methods used in the following examples are all conventional methods unless otherwise specified. The materials, reagents and instruments used are all conventional materials, reagents and instruments in the field unless otherwise specified, and can be obtained commercially by those skilled in the art. Bacillus cereus was purchased from Jiangsu Kebang Ecological Fertilizer Co., Ltd., Bacillus smithii, thermophilic denitrifying soil Bacillus was purchased from Jiangsu Kebang Ecological Fertilizer Co., Ltd., Bacillus licheniformis was purchased from Jiangsu Kebang Ecological Fertilizer Co., Ltd., and thermophilic urea Bacillus was purchased from Jiangsu Kebang Ecological Fertilizer Co., Ltd.; thermophilic actinomycetes were purchased from Henan Nanhua Qianmu Biotechnology Co., Ltd.; EM bacteria were purchased from Shandong Junde Biotechnology Co., Ltd.; white rot fungi were purchased from Shanghai Jiachu Bioengineering Co., Ltd., Chaetomium was purchased from Shandong Chunong Biotechnology Co., Ltd., Trichoderma harzianum was purchased from Shandong Changtai Biotechnology Co., Ltd., and Aspergillus niger was purchased from Shandong Changtai Biotechnology Co., Ltd.

[0016] Example 1: A method for promoting heat generation by corn straw composting using exogenous microbial agents, comprising the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure to obtain fermentation raw materials. When the mass ratio of chicken manure to fermentation raw materials is 1:3.2, the C / N ratio of the fermentation raw materials is 25:1.

[0017] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.45×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.45×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.45×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.45×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus was 0.45×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.5×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.33×10 8 CFU / g fermentation raw material; Chaetomium is 0.33×10 8 CFU / g fermentation raw material; Trichoderma harzianum is 0.33×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.33×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0018] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0019] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0020] Example 2: A method for promoting heat generation by corn straw composting using exogenous microbial agents, comprising the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0021] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.45×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.45×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.33×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.33×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus was 0.5×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.33×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.45×10 8 CFU / g fermentation raw material; Chaetomium is 0.33×10 8 CFU / g fermentation raw material; 0.4×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.5×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0022] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0023] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0024] Example 3: A method for promoting heat generation by corn straw composting using exogenous microbial agents, comprising the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0025] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.33×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.33×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.33×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.38×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus was 0.5×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.45×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.45×108 CFU / g fermentation raw material; Chaetomium is 0.5×10 8 CFU / g fermentation raw material; 0.4×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.4×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0026] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0027] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0028] Example 4: A method for promoting heat generation by corn straw composting using exogenous microbial agents, comprising the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0029] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.4×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.4×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.35×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.45×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus is 0.4×10 8CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.4×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.48×10 8 CFU / g fermentation raw material; Chaetomium is 0.4×10 8 CFU / g fermentation raw material; Trichoderma harzianum is 0.33×10 8 CFU / g fermentation raw material; Aspergillus niger was 0.46×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0030] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0031] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0032] Example 5: A method for promoting heat generation by corn straw composting using exogenous microbial agents, comprising the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0033] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.5×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.5×108 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.5×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.33×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus is 0.4×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.45×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.33×10 8 CFU / g fermentation raw material; Chaetomium is 0.33×10 8 CFU / g fermentation raw material; Trichoderma harzianum is 0.33×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.4×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0034] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0035] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0036] Comparative Example 1 A method for promoting heat generation by corn straw composting using exogenous microbial agents comprises the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0037] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.2×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.2×10 8 CFU / g fermentation raw material; Thermodenitrifying soil Bacillus is 0.4×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.7×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus was 0.5×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.5×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.33×10 8 CFU / g fermentation raw material; Chaetomium is 0.33×10 8 CFU / g fermentation raw material; Trichoderma harzianum was 0.41×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.5×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0038] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0039] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0040] Comparative Example 2 A method for promoting heat generation by corn straw composting using exogenous microbial agents comprises the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0041] Step 2: Lay a 0.5mm thick waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis, and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.45×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.45×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.45×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.45×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus was 0.45×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.1×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.33×10 8 CFU / g fermentation raw material; Chaetomium is 0.39×10 8 CFU / g fermentation raw material; 0.5×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.5×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0042] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0043] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0044] Comparative Example 3 A method for promoting heat generation by corn straw composting using exogenous microbial agents comprises the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0045] Step 2: Lay a 0.5mm waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.5×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.5×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.5×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.47×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus was 0.5×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.5×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.5×10 8 CFU / g fermentation raw material; Chaetomium is 0.2×10 8 CFU / g fermentation raw material; 0.2×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.2×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0046] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0047] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0048] Comparative Example 4 A method for promoting heat generation by corn straw composting using exogenous microbial agents comprises the following steps: Step 1: Crush the corn stalks to a length of 20 cm and a thickness of 1.5 cm, and then mix them with chicken manure. When the mass ratio of chicken manure to fermentation raw material is 1:3.2, the C / N ratio is 25:1, and the fermentation raw material is obtained.

[0049] Step 2: Lay a 0.5mm waterproof base film in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.5×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.5×10 8 CFU / g fermentation raw material; Thermodenitrificial soil Bacillus is 0.5×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.37×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus is 0.1×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.5×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.1×10 8 CFU / g fermentation raw material; Chaetomium is 0.5×10 8 CFU / g fermentation raw material; 0.5×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.5×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; The thickness of each layer of fermentation raw materials is 0.8m, and the total height of the pile is 2.8m, 6m wide and 12m long.

[0050] Step 3: Lay PE heat exchange pipes between the two layers of fermentation raw materials. The pipe spacing is 65cm, and a serpentine layout is adopted. The total length of each layer of heat exchange pipes is 5m / m. 2 Fermentation raw materials.

[0051] Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the bioreactor body to 10%. The outlet of the ventilation pipe is located at the center of the bottom of the first layer of fermentation raw materials.

[0052] The composting effects of Examples 1-5 and Comparative Examples 1-4 are shown in Table 1 below.

[0053] The calculation method of lignin degradation rate in Table 1 is as follows:

[0054] The cumulative heat supply (MJ / ton of raw material) in Table 1 refers to the total heat energy released by unit raw material during the energy conversion process. The calculation method is as follows: That is, 17.6 MJ of heat is released when each kilogram of organic carbon is completely oxidized. and are the initial and post-compost organic carbon contents (g / kg dry basis), respectively.

[0055] The calculation method of cellulose degradation rate in Table 1 is as follows:

[0056] Table 1 Lignin degradation rate (%) Cumulative heat supply (MJ / ton of raw material) Cellulose degradation rate (%) Example 1 52.9 3906 92.9 Example 2 50.1 3809 92.7 Example 3 51.1 3845 89.1 Example 4 50.1 3892 90.2 Example 5 50.2 3951 91.1 Comparative Example 1 39.1 2910 72.9 Comparative Example 2 32.9 3010 62.1 Comparative Example 3 35.3 2896 58.9 Comparative Example 4 33.2 2762 52.1

[0057] By comparing the data of Example 1-5 (high-efficiency group) and Comparative Example 1-3 (low-efficiency group), it was found that the total bacterial counts in both the high-efficiency group and the low-efficiency group were 4.07×10 8 CFU / g fermentation raw material, but the imbalance of the proportion of key bacterial species leads to differences in heat production efficiency. The synergistic effect of the bacterial flora function sequence is that the first layer (bottom layer) of thermophilic bacteria quickly starts to produce heat, mainly Bacillus cereus and Ureabacillus thermophilus, which release ammonia and heat through protein / urea decomposition. The amount of Ureabacillus thermophilus used in Example 1-5 is 0.4×10 8 CFU / g fermentation raw material and above, and heat production of 3800MJ / ton raw material or above; in comparative example 4, the amount of the bacteria used was only 0.1×10 8 CFU / g fermentation raw material, heat production dropped sharply by 30% (2762MJ / ton raw material). The second layer (transition layer) EM bacteria maintains metabolic continuity. EM bacteria (including photosynthetic bacteria, yeast, etc.) decompose small molecular organic matter, provide carbon sources for the upper fungi, and stabilize pH (inhibit ammonia volatilization). The lower limit of its critical dosage is 0.33×10 8 CFU / g fermentation raw material, the EM bacteria in Comparative Example 2 was only 0.1×10 8 CFU / g fermentation raw material, the lignin degradation rate dropped to 32.9%. The third layer (top layer) of fungi deeply degrades lignin, and white rot fungi (laccase) and Aspergillus niger (lignin peroxidase) break the phenylpropane structure of lignin through free radical oxidation. The cellulose degradation rate of Examples 1-5 is above 89%. In Comparative Example 1, due to the decrease in the addition amount of Bacillus cereus and Bacillus smithii, the cellulose degradation rate is only 72.9%. In Comparative Example 4, the dosage of thermophilic urea bacillus and white rot fungi is too low, and the imbalance of the proportion of key species makes it impossible to maintain the high temperature period. Thermophilic bacteria are the core bacteria for lignin degradation. Their insufficient activity directly causes the lignin degradation rate to drop from 52.9% to below 40%; the cellulose degradation rate drops sharply from 92.9% to below 70%. In Comparative Example 1, Bacillus licheniformis accounts for 0.7×10 8 CFU / g fermentation raw material may over-consume carbon source and inhibit the secretion of ligninase of white rot fungi.

[0058] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for promoting heat generation by corn straw composting using exogenous microbial agents, characterized in that: The steps include: Step 1: crushing corn stalks and mixing them with chicken manure to obtain a fermentation raw material, wherein the C / N ratio of the fermentation raw material is 25-30:1; the crushed corn stalks have a length of 5-30 cm and a thickness of 1-2 cm; Step 2: Lay a waterproof base film with a thickness of 0.2-0.5mm in the fermentation pit, lay the first layer of fermentation raw materials on the base film, and evenly sprinkle a mixed freeze-dried powder of Bacillus cereus, Bacillus smithii, thermophilic soil Bacillus denitrificans, Bacillus licheniformis and thermophilic urea Bacillus. The amount of each strain used is as follows: Bacillus cereus is 0.33-0.5×10 8 CFU / g fermentation raw material; Smith Bacillus is 0.33-0.5×10 8 CFU / g fermentation raw material; Thermophilic denitrifying soil Bacillus is 0.33-0.5×10 8 CFU / g fermentation raw material; Bacillus licheniformis is 0.33-0.45×10 8 CFU / g fermentation raw material; Thermophilic Ureabacillus is 0.4-0.5×10 8 CFU / g fermentation raw material; After laying the second layer of fermentation raw materials, evenly sprinkle EM bacteria freeze-dried powder, the usage amount is 0.33-0.5×10 8 CFU / g fermentation raw material; After laying the third layer of fermentation raw materials, evenly sprinkle the freeze-dried powder of white rot fungi, Chaetomium, Trichoderma harzianum and Aspergillus niger. The amount of each species used is as follows: White rot fungi are 0.33-0.48×10 8 CFU / g fermentation raw material; Chaetomium is 0.33-0.5×10 8 CFU / g fermentation raw material; The amount of Trichoderma harzianum was 0.33-0.4×10 8 CFU / g fermentation raw material; Aspergillus niger is 0.33-0.5×10 8 CFU / g fermentation raw material; After each layer of fermentation raw materials is laid, water is sprayed to adjust the moisture content. The first layer has a moisture content of 40%, the second layer has a moisture content of 50%, and the third layer has a moisture content of 55%; Step 3: Lay heat exchange pipes between the two layers of fermentation materials. The pipe spacing is 60-80cm. A serpentine layout is adopted. The total length of each layer of heat exchange pipes is 1-50m / m. 2 Fermentation raw materials; Step 4: A ventilation pipe is pre-buried at the bottom of the first layer of fermentation raw materials. The oxygen content detector is located at the center of the bottom of the first layer of fermentation raw materials. During the fermentation process, a blower is used to inflate the ventilation pipe to adjust the oxygen content of the pile to 5-15%.

2. The method for promoting heat generation by corn straw composting using exogenous microbial agents according to claim 1, characterized in that: The thickness of each layer of fermentation raw materials is 0.8-1m, the total height of the pile is 2.8-3m, the width is 5-6m, and the length is 11-12m.

3. The method for promoting heat generation by corn straw composting using exogenous microbial agents according to claim 1, characterized in that: The heat exchange pipe is made of PE material.

4. The method for promoting heat generation by corn straw composting using exogenous microbial agents according to claim 1, characterized in that: The outer layer of the stack is covered with a 0.5 mm polyethylene thermal insulation film, and the inner layer is covered with an aluminum foil reflective layer.

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