Method for eliminating ammonia inhibition in anaerobic fermentation process of livestock and poultry excrement

Abstract

The invention provides a method for eliminating ammonia inhibition in an anaerobic fermentation process of livestock and poultry excrement. According to the method, a struvite crystallization and sedimentation technology is used for detecting the concentration of NH<4+> in an ammonia inhibition system under the conditions that the pH value is 7-9, and the mass concentration ratio of volatile fatty acid to total inorganic carbon is less than 0.4; magnesium salt and phosphorus salt are added into a livestock and poultry excrement fermentation reaction system according to a molar ratio of the NH<4+> to Mg<2+> to PO4<3-> being equal to 1: 1: 1; the concentration of ammonia nitrogen is reduced to about a concentration value of the fermentation process without ammonia inhibition. The method for eliminating the ammonia inhibition in the anaerobic fermentation process of the livestock and poultry excrement is established by studying the influence factors of an ammonium magnesium phosphate reaction in the inner environment of an anaerobic fermentation tank and the self-limiting factors of the reaction. The method is simple in technology; furthermore, struvite precipitation produced in the reaction is slow release fertilizer, and not only can eliminate the ammonia nitrogen inhibition, but also can recover nutrients such as nitrogen and phosphorus, so that the operating cost is lowered.

Description

technical field [0001] The invention relates to the field of resource utilization of agricultural waste, in particular to a method for releasing ammonia inhibition during anaerobic fermentation of livestock and poultry manure based on ammonium magnesium phosphate reaction. Background technique [0002] With the gradual improvement of the modern animal husbandry industry system and the rapid development of the economy, the production mode of animal husbandry has undergone major changes, gradually changing from decentralized and extensive to large-scale and intensive operations, and the discharge of livestock and poultry manure has increased sharply. And the resulting environmental problems are becoming more and more prominent. Biogas production by anaerobic fermentation has received widespread attention and rapid development around the world in recent years because of its dual functions of controlling livestock and poultry manure environmental pollution and alleviating the pr...

AI Technical Summary

Problems solved by technology

At present, this technology is mainly used in the treatment of industrial high-ammonia-nitrogen wastewater and the recovery and utilization of nitrogen and phosphorus nutrients. The treatment of biogas slurry outside the reaction tank only needs to consider how to increase the recovery efficiency, but it is used for ammonia in the anaerobic reaction process. Inhibition removal needs to consider the influence of the pH change of the reaction tank and the addition of foreign ions on the stability of the reaction system. At the same time, it is necessary to ensure the normal and stable operation of the anaerobic project. It is still technically difficult to achieve accurate regulation and release the ammonia inhibition during the fermentation process.

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