83 / 2023-07-04 21:46:56

Thoughts on quality standards and gas emission reduction of livestock and poultry manure composting industry

Livestock and poultry manure; Composting; Industrial standard; Harmless; Gas emission reduction; Semi-permeable membrane

Composting is the main method for the harmless treatment and resource utilization of the solid part of livestock and poultry manure. The main processes include windrow composting, trough composting, reactor composting, and membrane-covered composting. Harmless treatment is the key to the success of livestock and poultry manure composting, and nitrogen retention and odor reduction are the key points to reduce nitrogen loss and protect the environment during composting. At present, the current domestic standards require that the total nutrient content of organic fertilizer is greater than 4%, and the organic matter is greater than 30%. Most of the organic fertilizers from livestock and poultry manure after composting are difficult to meet the standards. It is difficult to sell the organic fertilizers from livestock and poultry manure compost without adding chemical fertilizers or other auxiliary materials. Therefore, it is strongly recommended to reduce or eliminate the requirements for organic matter and nutrient indicators in domestic standards to promote the resource utilization of livestock and poultry manure. In the current epidemic era, we should pay attention to the killing effect of composting on pathogenic microorganisms in livestock and poultry manure, and pay attention to the health risks faced by the workers in the process of industrial composting. In the times of “double carbon”, we should pay attention to the reduction of greenhouse gases and gas pollutants in the process of industrial composting. Open-type composting obviously can not meet the needs of the development of the times. In recent years, semi-permeable membrane composting technology developed on the basis of windrow composting and trough composting can be applied to composting scenarios at different scales, and has advantages in composting cycle, investment cost, odor emission reduction and so on.