Composting process control of fertilizer production process

① Temperature control. In the fertilizer production process, the fermentation temperature of the compost should be controlled at 50-60 ℃. When the temperature of the compost exceeds 60 ℃, the compost should be turned over or forced ventilation should be carried out. The temperature of the compost should be kept above 50 ℃ for 5~10 days for primary fermentation.

② Moisture control. Maintaining appropriate moisture content is the first condition to promote microbial activity and compost fermentation. Generally, 60% - 75% of the maximum water holding capacity of composting material is suitable. With the decrease of water content in compost fermentation, the water content should be 36% ~ 45% at the end of primary fermentation;
③ Compost oxygen concentration. In the fertilizer production process, keep appropriate air in the pile, which is conducive to the propagation and activity of aerobic microorganisms, and promote the decomposition of organic matters. When composting at high temperature, more attention should be paid to the appropriate packing tightness to facilitate ventilation. The oxygen concentration in the compost is kept above 3% by compost windrow turner or forced ventilation.

④ Maintain a neutral or slightly alkaline environment. Lime or calcareous soil can be added in proper amount to neutralize and regulate acidity and promote microbial propagation and activity.

⑤ C / N ratio. The ratio of carbon to nitrogen for normal decomposition of organic matter was 25:1. The ratio of carbon to nitrogen of legume green manure was 15-25:1, weeds 25-45:1, and stems 60-100:1. Therefore, according to the types of composting materials, add some substances with high nitrogen content to reduce the carbon nitrogen ratio and promote microbial activities.