The microbiological process of aerobic fermentation can be roughly divided into three stages, each with its unique microbial community:
1. Heat generation stage (intermediate temperature stage, heating stage) In the early stage of fermentation (usually 1-3 days), thermophilic microorganisms in the compost pile use soluble and easily degradable organic matter as a source of nutrition and energy, rapidly proliferate, and release heat energy, causing the temperature of the compost pile to continuously rise.
. At this stage, the temperature is within the range of room temperature to 45 ℃, and the microorganisms are mainly mesophilic and aerobic, usually some non spore bacteria. There are many types of microorganisms, mainly bacteria, fungi, and actinomycetes. Among them, bacteria mainly utilize water-soluble monosaccharides, while actinomycetes and fungi have special functions in decomposing cellulose and hemicellulose substances p> 2. In the high-temperature stage, when the temperature of the fertilizer pile rises to above 45 ℃, it enters the high-temperature stage. Usually, starting from pile fermentation, the temperature of the compost pile can quickly rise to 55 ℃ within 2-3 days, and the pile temperature can reach a high value within one week (high temperature can reach 80 ℃). Thermophilic microorganisms are inhibited and gradually replaced by thermophilic microorganisms. In addition to the residual and newly formed soluble organic compounds in the previous stage continuing to decompose and transform, complex organic compounds such as hemicellulose, cellulose, and proteins also begin to strongly decompose. The main active species around 50 ℃ are thermophilic fungi and actinomycetes; When the temperature rises to 60 ℃, fungi almost completely cease activity, with only thermophilic actinomycetes and bacteria active; When the temperature rises above 70 ℃, most thermophilic microorganisms are no longer suitable, and a large number of microorganisms die or enter a dormant state. At this point, the generated heat decreases and the reactor temperature automatically drops. When the reactor temperature drops below 70 ℃, dormant thermophilic microorganisms resume their activity and continue to decompose recalcitrant organic matter, resulting in an increase in heat. The reactor temperature is then in a naturally regulated and prolonged period of high temperature. High temperature plays an important role in the rapid maturation of fermentation, during which the formation of humus begins and black substances that can dissolve in weak alkalis begin to appear. The C/N ratio significantly decreases, and the height of the fertilizer pile decreases accordingly. High temperature can effectively kill pathogens in organic waste. According to China's high-temperature fermentation hygiene standard (GB7959-87), it is required to ferment at a high temperature of 50-55 ℃ or above for 5-7 days p>3. The maturation stage is at the end of the high-temperature stage, leaving only a portion of difficult to decompose organic matter and newly formed humus. At this time, microbial activity decreases, heat generation decreases, and temperature drops.
. At this point, thermophilic microorganisms dominate and further decompose the remaining organic matter that is difficult to decompose. Humus continues to increase and tends to stabilize, and fermentation enters the maturation stage p> After cooling, the oxygen demand decreases significantly, the gaps in the fertilizer pile increase, and the oxygen diffusion ability is enhanced. At this time, only natural ventilation is needed. The common post ripening treatment in forced ventilation fermentation is to flip the aerated pile once, stop aeration, and let it rot. It can also play a role in nitrogen retention. Microbial fermentation refers to the process of using microorganisms to convert raw materials into products needed by humans through specific metabolic pathways under suitable conditions. [1] The level of microbial fermentation production mainly depends on the genetic characteristics and cultivation conditions of the strains themselves. The application scope of fermentation engineering includes pharmaceutical industry, food industry, energy industry, chemical industry, agriculture: transforming plant genes; Biological nitrogen fixation; Engineering insecticidal and biopesticides; Microbial nutrients. Environmental protection and other aspects p> & Nbsp& Nbsp& Nbsp; In summary, Jiumu Biotechnology, a manufacturer of aerobic fermentation tanks, has shared some relevant information about aerobic fermentation with you. For more details, please follow: http://www.ayjmsw.com/