CN115368175A

CN115368175A - Aerobic composting method covered by molecular film

Info

Publication number: CN115368175A
Application number: CN202210908036.4A
Authority: CN
Inventors: 章万喜; 陈志励; 何丽君; 梁慧敏
Original assignee: Guangdong Xiran Environmental Technology Research Co ltd
Current assignee: Guangdong Xiran Environmental Technology Research Co ltd
Priority date: 2022-07-29
Filing date: 2022-07-29
Publication date: 2022-11-22

Abstract

The invention relates to a molecular film covered aerobic composting method, which comprises the following steps of crushing and mixing aerobic composting raw materials, namely livestock and poultry manure and carbon organic wastes; spraying conventional decomposed microbial inoculum into the aerobic composting raw materials, and then piling up into a pile body, wherein the bottom of the pile body is provided with a ventilation pipeline for supplying oxygen. The periphery and the center of the pile body are provided with brackets, the molecular membrane covers the aerobic compost pile through the membrane bracket, and the aerobic composting and the aging are completed after a certain time. After the aerobic composting and aging are finished, screening the materials, and feeding the screened materials into a finished product workshop; and returning oversize materials to the mixing workshop. After the organic waste is biodegraded, converted and stabilized for a certain time, a crude organic fertilizer is formed. Parameters of the aerobic compost pile are monitored by various sensors during the aerobic composting. The molecular film covering aerobic composting technology has the advantages of small investment of fixed assets, short treatment period, low cost, wide application, strong adaptability to climatic conditions and capability of producing better biological organic fertilizer.

Description

Aerobic composting method covered by molecular film

Technical Field

The invention belongs to the technical field of agriculture, and relates to a molecular film covering aerobic composting technology.

Background

Aerobic composting is a process of absorbing, oxidizing and decomposing waste by aerobic bacteria under the conditions of good ventilation and sufficient oxygen. Aerobic microorganisms oxidize a part of absorbed organic matters into simple inorganic matters through self life activities, release energy required by the growth activities of the microorganisms, and synthesize the other part of the organic matters into new cytoplasm, so that the microorganisms continuously grow and reproduce to generate more organisms.

Generally, the aerobic composting can realize the reduction, resource and harmless treatment and utilization of organic solid waste resources. Aerobic composting is an extremely complex physical and chemical change process accompanied by the change processes of growth, metabolism, reproduction, death, population replacement and the like of microorganisms, and can be roughly divided into four stages.

A heating stage: the aerobic composting process of the compost is started by microorganisms, organic substances (such as simple saccharides, starch, protein and the like) which are easy to decompose are decomposed vigorously under aerobic conditions, a large amount of heat is generated, the composting temperature is continuously increased from about 20 ℃ to 40 ℃.

And (3) high-temperature stage: along with the increase of the temperature, the thermophilic microorganisms gradually replace the mesophilic species to play a leading role, the temperature is continuously increased, generally reaches more than 50 ℃ within a few days, and the high-temperature stage is started. In the high temperature stage, thermoactinomyces and Thermofungi are the main species. They strongly decompose complex organic substances (such as cellulose, hemicellulose, pectin substances and the like) in the compost, accumulate heat and raise the temperature of the compost to 60-70 ℃.

And (3) cooling: when the high-temperature stage lasts for a certain time, most of cellulose, hemicellulose and pectin substances are decomposed, complex components (such as lignin) which are difficult to decompose and newly formed humus are left, the activity of microorganisms is weakened, and the temperature is gradually reduced. When the temperature drops below 40 ℃, mesophilic microorganisms become a dominant species again.

And (3) decomposing and preserving fertilizer: after the compost is thoroughly decomposed, the volume is reduced, the temperature of the compost is reduced to be slightly higher than the air temperature, and the compost is tightly pressed to cause an anaerobic state, so that the mineralization of organic matters is weakened, and the fertilizer is favorably preserved.

The traditional aerobic composting technology comprises a strip pile turning throwing type aerobic composting technology, a groove type aerobic composting technology, a tower type aerobic composting technology, a kiln type aerobic composting technology and the like. The technology for performing harmless aerobic composting and decomposing treatment on organic wastes by adopting the traditional aerobic composting method is widely used in the field of organic solid waste treatment at present, but the traditional method for performing aerobic composting treatment on organic solid wastes has many problems: special indoor aerobic composting tanks, aerobic composting workshops and special aerobic composting machinery need to be built, the investment of fixed assets of matched infrastructure of the aerobic composting is large, and the mobile operation of a treatment system cannot be realized; the control difficulty of the peculiar smell of the aerobic compost is high. The aerobic composting product has incomplete sterilization, low killing rate, long aerobic composting period and high aerobic composting cost; the aerobic composting needs to be manually detected for the composting parameters, especially in the northern winter when the composting parameters are monitored in real time for 24 hours; the problem of normal aerobic composting in winter in cold areas cannot be solved, the utilization efficiency of factories is low, and cold areas in the north can only do compost for 6 months all year round.

Disclosure of Invention

In view of this, the task of the invention is to provide a molecular film covering aerobic composting technology, which achieves the aims of strong maneuverability, strong applicability, low cost, short period, less pollution, less odor, intellectualization and perennial high-efficiency treatment of organic solid wastes.

The technical scheme of the invention is as follows: a molecular film covered aerobic composting technology comprises the steps of mixing livestock and poultry manure with one or more of coconut shells, sawdust, cassava residues, rice hulls, peanut shells, mushroom residues, crushed straws, mushroom residues, wood processing wastes, corn processing wastes and biomass particle processing wastes, and then putting the mixture into a compost space of a molecular film covered aerobic composting system for composting, wherein the film covered aerobic composting system comprises a compost ground, a film framework, a polytetrafluoroethylene film, a pressure sensor, a humidity sensor and a pH sensor. The ground of the stack body is provided with a plurality of ventilation grooves. The periphery and the top of the polytetrafluoroethylene membrane are connected with the membrane support, the expanded polytetrafluoroethylene membrane, the membrane support and the pile ground are enclosed to form a pile space, and air is pumped into the ventilation groove through an air blower in the composting process. After 20 days, when the temperature of the compost is measured to be reduced to below 50 ℃ through the temperature sensor, the high-temperature stage of the compost is finished, the odor generated by the compost is obvious, after the after-ripening process of the compost is finished, the polytetrafluoroethylene film can be lifted, the compost is screened, and the screened materials enter a finished product workshop to be prepared into the organic fertilizer; and returning oversize materials to the mixing workshop. The polytetrafluoroethylene membrane has a selective ventilation function, and most of odor dissipated in the composting process of the pile body cannot pass through the expanded polytetrafluoroethylene membrane and is trapped in the pile body and decomposed by abundant microorganisms in the pile body. Meanwhile, part of water vapor generated in the composting process of the pile can pass through the polytetrafluoroethylene membrane, so that the moisture of the pile is reduced.

Preferably, the mass ratio of the livestock and poultry manure to the carbon organic waste is 4-6: 3 to 4.

Preferably, the carbon-nitrogen ratio of the livestock and poultry manure to the carbon organic waste is 25-30.

Preferably, after the livestock and poultry manure and the carbon organic waste are mixed and before aerobic composting, the moisture is controlled to be between 50 and 60 percent.

Preferably, the pH value is 5.5-8.0 after the livestock and poultry manure and the carbon organic waste are mixed and before aerobic composting.

Preferably, the stack is a stack of strips 150-200cm high.

Preferably, the expanded polytetrafluoroethylene membrane is uniformly provided with a pressure sensor, a temperature sensor, a humidity sensor and a pH sensor.

Preferably, the membrane frameworks are arranged on the two sides and the middle of the stack body, the peripheral supports are 20cm higher than the ground, the middle supports are 20cm higher than the top of the stack, and the polytetrafluoroethylene membrane is fixed through the membrane frameworks.

Preferably, the compost pile is ventilated and supplied with oxygen through 3-5 ventilating ducts.

Compared with the prior art, the invention has the advantages that: the method is combined with the synergistic composting of various organic wastes, and the raw materials with different types and physical and chemical properties are compounded to stabilize and improve the taste of the raw materials, thereby laying a foundation for producing high-quality organic fertilizers, realizing the package synergistic treatment and utilization of various organic wastes, improving the utilization efficiency of resources and reducing the overall investment and operation cost. By the mode of coating the film on the portable framework, the mobile operation of the processing system can be realized, the maneuverability of an operation field is improved, and the investment of infrastructure fixed assets is reduced. The molecular film covers to solve the problem of odor overflow of aerobic composting, and meanwhile, the molecular film has a heat preservation process, so that the problem of normal aerobic composting in winter in cold regions can be solved. The pressure sensor, the humidity sensor, the temperature sensor and the PH sensor on the membrane can greatly facilitate the work of workers, and the purpose of intelligent real-time monitoring is achieved.

Drawings

FIG. 1 is a schematic view of a membrane-covered aerobic composting system.

1, 12, 13 in fig. 1: a membrane scaffold; 2: a molecular film; 3: CO2;4: a temperature sensor; 5: a humidity sensor; 6: a pressure sensor; 7: a pH sensor; 8: weather resistance; 9: an oxygen sensor; 10: water vapor; 11: an organic material; 14: heat; 15. 16, 17: oxygen gas; 18: smell; 19: moisture; 20: and (5) pathogenic bacteria.

Detailed Description

The preferred embodiments of the present invention will be described in detail below. The experimental procedures, in which specific conditions are not specified in the examples, are generally carried out under conventional conditions or under conditions recommended by the manufacturers.

Example 1

Molecular film covering aerobic composting technology:

the method comprises the steps of crushing and stirring aerobic composting raw materials, namely livestock and poultry manure and carbon organic wastes, spraying organic aerobic composting bacteria into the aerobic composting raw materials, pushing the aerobic composting raw materials into an aerobic composting groove to pile, covering a composting molecular film, decomposing, fermenting, aging, detecting, air drying, screening and bagging.

The biological organic fertilizer comprises the following main raw materials: and (5) separating the pig manure in a dry and wet manner. Auxiliary materials: dry substances such as coconut shells, sawdust, manioc waste, rice hulls, peanut shells, mushroom slag, crushed straws, mushroom slag, wood processing waste, corn processing waste, biomass particle processing waste and the like.

The water content of the raw materials is controlled to be 60-65%, the PH value is controlled to be 5.5-8, and the volume weight is 0.5-0.60 ton/m < 3 >; aerobic compost pile parameters: 38-6.5-1.5 (m).

1. Mixing pig manure with auxiliary materials (dry matters such as crop straws, mushroom residues, wood processing waste, corn processing waste, biomass particle processing waste and the like) and the like, uniformly mixing the raw materials with a special microbial inoculum for aerobic composting after the water content of the raw materials is lower than 60 percent.

2. After the pig manure, the auxiliary materials and the aerobic composting bacteria are stirred uniformly as much as possible, the pig manure, the auxiliary materials and the aerobic composting bacteria are pushed into an aerobic composting groove to be piled into a pile, and the pile is piled into a strip pile with the height of 150 cm.

3. A20 cm support was mounted around the stack and the center support was set up (about 160 cm) before the addition of the batch. Through the support, the molecular film was covered onto the stack.

4. Covering compost high molecular film to make aerobic compost, when the aerobic compost is made, its temperature is controlled below 70 deg.C, generally about 20 days, it can obtain odorless effect, i.e. completely fermented and decomposed. The compost made by matching the e-PTFE film with the base material is covered by the polymer film in the aerobic composting process, so that a real 'climate box' is created for compost materials and is not influenced by external climate. The high-performance membrane material used by the molecular membrane has a molecular filtration microporous structure, so that peculiar smell can be effectively controlled, and bacteria can be thoroughly eliminated. 3 ventilation pipelines are laid below the strip stack to inject air into the strip stack, air molecules and water vapor molecules in the stack body can normally pass through the molecular membrane, external water molecules cannot enter the molecular membrane, and aerobic composting conditions required by conversion of waste into high-quality compost by biological bacteria are formed inside the membrane in a short time. Real-time online data transmission can be realized by installing a pressure sensor, a temperature sensor, a humidity sensor and a PH sensor oxygen sensor on the membrane, and the problem of manual monitoring is solved. The film covering is realized by the film support around the strip pile, the field loading and unloading can be carried out, and the problems that a special indoor aerobic composting groove, an aerobic composting workshop and an aerobic composting special machine need to be built, the investment of fixed assets of an aerobic composting matched infrastructure is large, and the moving operation of a treatment system cannot be realized are solved. After 20 days, when the temperature of the compost is measured to be reduced to below 50 ℃ by a temperature sensor, the high-temperature stage of the compost is finished, the odor generated by the compost is obvious, after the post-ripening process of the compost is finished, the polytetrafluoroethylene film can be lifted, and the compost is screened.

5. Air drying, crushing and sieving: transporting the organic fertilizer after aerobic composting to an outdoor sunning ground, naturally drying in the sun and ensuring that the water content is below 20 percent, namely finishing air drying, crushing the air-dried raw material by a crusher, sieving to remove impurities such as crude fibers which are not completely decomposed, and sieving with a sieve with the pore size of 2.5mm.

Example 2: the biological organic fertilizer comprises the following main raw materials: 400 tons of pig manure waste per day. Auxiliary materials: 200 tons/day of dry matters such as crushed coconut shells and the like, the annual demand is 7.3 ten thousand tons, and the water content is calculated according to 40%; the low-water aerobic compost is returned to 100 tons/day, and the water content is calculated according to 40 percent; the water content of the main material and the auxiliary material is adjusted to 63 percent of a reasonable level after stirring. The C/N ratio is 27, the pH value is 1, and the single-pile aerobic composting period is designed to be 18 days. Aerobic compost pile parameters: 35-6-1.7 m, the concrete aerobic composting method is the same as that in example 1.

Example 3: the biological organic fertilizer comprises the following main raw materials: dry-wet separation of pig manure 35 tons/day, auxiliary materials: 12t/d of dry matters such as crop straws, mushroom residues, wood processing wastes, corn processing wastes and biomass particle processing wastes. Adjusting the initial moisture of the livestock and poultry manure aerobic compost to a reasonable level of about 60%, wherein the C/N ratio is 1, and the pH value is 5-9. The period of single pile aerobic composting is designed to be 20 days, and the pile parameters of the aerobic composting are as follows: 38-6.5-1.5 meters, and 3 pile positions are designed. The aerobic composting process was the same as in example 1.

Example 4: the biological organic fertilizer comprises the following main raw materials: 10 tons of chicken manure per day. Auxiliary materials: peanut shells, mushroom residues, crushed straws and the like. Adjusting the initial moisture of the livestock and poultry manure aerobic composting to a reasonable level of about 60%, wherein the C/N ratio is 28. The period of single pile aerobic composting is designed to be 20 days, and the pile parameters of the aerobic composting are as follows: 30-5-1.5 m. The aerobic composting process was the same as in example 1.

Example 5: the biological organic fertilizer comprises the following main raw materials: cow dung 20 tons/day. Auxiliary materials: 200kg of cassava and 100kg of straws. Adjusting the initial moisture of the livestock and poultry manure aerobic compost to a reasonable level of about 60%, wherein the C/N ratio is 27. The single-pile aerobic composting period is designed to be 20 days, and the aerobic composting parameters are as follows: 30-5-1.5 m. The specific aerobic composting method is the same as in example 1.

Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, while the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims

1. The method for aerobic composting by molecular film coverage is characterized in that the specific steps of aerobic composting by molecular film coverage are as follows:

a: carrying out crushing and stirring treatment on composting raw materials, namely livestock and poultry manure and carbon organic wastes;

b: spraying organic aerobic composting bacteria into the aerobic composting raw material;

c: then pushing the mixture into an aerobic composting groove to be piled, ventilating and supplying oxygen in the composting groove through a ventilating pipeline, covering a molecular membrane through a membrane framework, compacting to form an air bin, and carrying out aerobic composting;

d: after 15-20 days of aerobic composting, aging for 14 days, screening the materials, and making the screened materials into an organic fertilizer after entering a finished product workshop; returning oversize materials to the mixing workshop;

e: during aerobic composting, the pressure sensor, the Ph sensor, the temperature sensor, the humidity sensor and the oxygen sensor which are arranged on the membrane monitor relevant parameters of the aerobic composting pile in real time.

2. The aerobic composting method covered by molecular film as claimed in claim 1, wherein the livestock and poultry manure is one or a combination of pig manure, sheep manure, bird manure, chicken manure, cow manure and duck manure.

3. The aerobic composting method covered by molecular film as claimed in claim 1, wherein the carbon-based organic waste is one or more of coconut shell, sawdust, manioc waste, rice hull, peanut shell, mushroom residue, crushed straw, mushroom residue, wood processing waste, corn processing waste, and biomass particle processing waste.

4. The aerobic composting method covered by molecular film as claimed in claim 1, wherein the carbon organic waste is crushed by a vertical crusher, mixed by double helix stirring and fed by an aerobic compost quantitative feeder, and both the machines are controlled by PLC control system.

5. The aerobic composting method of claim 1, wherein the mass ratio of livestock and poultry manure to carbon organic waste is 4-6: 3-4, and the carbon nitrogen ratio is 25-30.

6. The aerobic composting method of claim 1 wherein the water content of the raw materials in the bio-organic fertilizer is controlled between 50-60% before aerobic composting and the pH is 5.5-8.0.

7. A method for aerobic composting covered by a molecular film according to any of claims 1-6, wherein the film used for covering is a polytetrafluoroethylene film.

8. The aerobic composting method of claim 7 wherein the molecular membranes are covered by membrane holders, the membrane holders are holders standing around and in the center of the stack, the peripheral holders are 20cm above the ground and the central holder is 20cm above the top of the stack.

9. A method for aerobic composting covered by molecular film according to claim 1, characterized in that in step c the aeration is carried out in the composting trough of windrow with 150-200cm height by 3-5 ventilating ducts.

10. A method for aerobic composting covered by a molecular film according to claim 1 where the monitoring of relevant parameters in step e is done in order to adjust in time if important parameters are not found in reasonable intervals.