Process flow of aerobic composting

The process flow is mainly: pre-treatment ~ main fermentation ~ post-fermentation ~ post-treatment ~ storage.

Pre-treatment of raw materials: including sorting, crushing and adjustment of water content and carbon to nitrogen ratio. First remove the impurities such as metal, glass, plastic and wood from the waste and crush it to a particle size of about 40 mm, then select the composting raw materials for batching in order to adjust the water content and carbon to nitrogen ratio, which can be mixed composting using pure garbage, garbage and manure in the ratio of 7:3 or garbage and sludge in the ratio of 7:3.

Fermentation stage of raw materials: most of our country adopts primary fermentation, the cycle is as long as 30 days, and now adopts secondary fermentation, the cycle generally uses 20 days. Primary fermentation is an aerobic composting medium and high temperature two stages of microbial metabolism process, specifically from the beginning of fermentation, through the medium temperature, high temperature and then arrived at the temperature began to decline in the whole process, generally takes 10-12 days, high temperature stage lasts longer. Secondary fermentation refers to the material after the primary fermentation, there is a part of easy to decompose and a large number of difficult to decompose organic matter exists, need to be sent to the back of the fermentation room, piled up into 1-2 meters high stack for secondary fermentation and putrefaction. When the temperature is stabilized at about 40℃, it will reach the maturity, and it usually takes 20-30 days.

Post-processing stage: is the fermentation of mature compost treatment, further removal of compost in the pre-treatment process did not remove the impurities and the necessary crushing process, after the treatment of the refined compost water content of about 30%, the carbon and nitrogen ratio of 15-20.

Storage stage: storage refers to the compost treatment must be stacked before management, generally can be stored directly, but also can be stored in a pile. Generally can be stored directly, can also be stored in bags. But the storage should pay attention to keep dry and ventilated, to prevent moisture closure. Divided into three processes: the beginning stage, high temperature stage, maturation stage.