Method for comprehensively recycling fecal sewage of large-scale livestock and poultry farms and farmland crop straws

Abstract

The invention relates to a method for comprehensively recycling the fecal sewage of large-scale livestock and poultry farms and farmland crop straws, which comprises the following steps of: (1) performing anaerobic digestion, namely regulating the solid content of the fecal sewage of livestock and poultry to be between 5 and 10 percent, adding anaerobic digestion inocula, and performing the anaerobic digestion to generate methane; (2) performing energy utilization on the methane, namely purifying the methane obtained in the step (1) to be used as fuel gas or allowing the purified methane to be used for power generation to perform energy utilization; (3) performing solid-liquid separation, namely performing the solid-liquid separation on biogas residues and biogas slurry which are obtainedin the step (1) to obtain the biogas slurry and the biogas residues of which the moisture content is about 60 percent; (4) preparing a biological organic compound fertilizer from the biogas slurry, and mixing the biogas residues and part of biogas slurry with the straws and part of excrement to perform aerobic compost; and (5) mixing and performing the aerobic compost, namely mixing part of biogas slurry obtained in the step (3) and the crushed straws, regulating the moisture content of the mixture to be between 50 and 60 percent, and performing the aerobic compost. In the method, clean resources are recovered by the anaerobic digestion, and the biogas slurry is used for producing the biological organic compound fertilizer with a high additional value.

Description

technical field [0001] The invention belongs to the field of renewable energy development and utilization and environmental protection, and specifically relates to a resource for anaerobic digestion of feces and sewage in large-scale livestock and poultry farms, biogas utilization, biogas slurry fertilizer, biogas residue and straw mixed aerobic composting utilization method. Background technique [0002] With the rapid development of the livestock and poultry breeding industry, large-scale and intensive livestock and poultry farms continue to increase, and the excrement emissions from breeding have increased dramatically. Livestock and poultry manure is rich in nitrogen, phosphorus, potassium and organic matter, and also contains a lot of volatile substances, pathogenic microorganisms, parasite eggs and heavy metals. If it is directly applied to farmland without treatment, it will bring harm to the ecological environment and human and animal health. to negative effect. ...

AI Technical Summary

Problems solved by technology

However, in the current utilization, except a small amount of straw is used as livestock feed, farm manure and rural fuel, most of the

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