Method for producing biogas through two-phase anaerobic fermentation of piggery wastewater

Abstract

The invention discloses a method for producing biogas through two-phase anaerobic fermentation of piggery wastewater. The method comprises steps as follows: the piggery wastewater flows into an adjusting tank to be uniformly stirred after impurities are filtered by a grating tank; uniformly stirred wastewater in the adjusting tank flows into an acidification tank for high-temperature hydrolytic acidification treatment, and an acidizing fluid is obtained; the acidizing fluid is pumped into a black film biogas digester to be fermented to produce biogas; biogas is purified and connected with a biogas power generator for power generation; the biogas power generator, a heat exchanger and a hot water tank are connected sequentially and are used for recovering waste heat produced by power generation, forming hot water and sending the hot water to an acidification tank to increase the temperature. By means of the method, acidification and hydrolysis of organic matter in the piggery wastewaterare promoted, the gas producing efficiency and the gas output of the black film biogas digester are increased, and the problem of difficulty in slag discharge of the black film biogas digester is solved; the obtained biogas residues are used for producing compound organic fertilizer, the biogas is used for power generation, waste heat of power generation is used for acidification and hydrolysis, and the method has good ecological benefits and economic benefits and is applicable to large-scale pig farms.

Description

technical field [0001] The invention belongs to the technical field of energy saving and environmental protection, and in particular relates to a method for producing biogas by two-phase anaerobic fermentation of pig farm wastewater. Background technique [0002] Large-scale pig farms have a large output of feces, and the COD, ammonia nitrogen, total phosphorus and other indicators in the wastewater are seriously exceeded, the color is deep, and the pungent smell is strong. cause secondary pollution and endanger human health. With the acceleration of my country's environmental protection and the improvement of pollutant discharge standards in the livestock and poultry breeding industry, a set of high-efficiency and low-cost livestock and poultry manure treatment technology has become an urgent need for the livestock and poultry breeding industry. [0003] The black film biogas digester is a super-large-volume biogas digester integrating anaerobic fermentation, gas productio...

AI Technical Summary

Problems solved by technology

[0003] The black film biogas digester is a super-large-volume biogas digester integrating anaerobic fermentation, gas production and gas storage. It has the advantages of large capacity, high impact load resistance, low operating cost, and low engineering cost. It is widely used in large-scale farming in South China It has been widely used in the field, but there are problems such as low organic matter degradation efficiency, low gas production rate and gas production efficiency, and difficult biogas residue cleaning.

Images