A kind of anaerobic treatment method of livestock and poultry manure

Abstract

The invention discloses a livestock and poultry manure anaerobic processing method, and belongs to the field of technologies for converting livestock and poultry manures into resources and energy. The method comprises the following steps: directly adding non-diluted manures with a solid content of 25 to 30% into a pyrohydrolysis tank to carry out dryness-type low-temperature pyrohydrolysis for 1 to 3 days at a temperature of 65 to 75 DEG C, and then carrying out high solid content anaerobic digestion under a solid content of 10 to 12%. After the anaerobic digestion, the digestion products can be diluted by the biogas slurry, which has been subjected to solid / liquid separation, or water from other sources. The anaerobic digestion can be carried out at a temperature range of 35 + / - 5 DEG C or 55 + / - 5 DEG C. The dryness-type low-temperature pyrohydrolysis can break through the bottleneck (hydrolytic acidification) of livestock and poultry manure anaerobic digestion and increases the biogas yield by 60% or so. Compared with the conventional anaerobic digestion method, the provided method has the advantages of reduced reactor volume, operation cost, and energy consumption, and little amount of biogas slurry and biogas residue. Moreover, the method can reduce the hygiene risk of biogas slurry and biogas residues in agricultural application, and meets the requirements of solid pasteurization of environmental protection agency (EPA).

Description

technical field [0001] The invention belongs to the resource and energy conversion technology of livestock and poultry manure, and mainly relates to an anaerobic digestion treatment method of livestock and poultry manure. Background technique [0002] Livestock manure is a pollutant with high organic matter, high ammonia nitrogen, and high solid content. It also emits foul odor and seriously affects air quality. In addition, poultry manure contains a large number of pathogenic bacteria and parasite eggs, which have great potential harm to human health and environmental safety. Anaerobic digestion is one of the commonly used processes for manure treatment. It can recover biogas while degrading organic matter, and can also remove part of the stench and inactivate pathogenic bacteria and parasite eggs. The biogas yield of traditional anaerobic digestion is high, but due to the low solid content (1% to 5%), the volume of the reactor is large, the heating energy consumption is h...

AI Technical Summary

Problems solved by technology

Low-temperature thermal hydrolysis is usually only used as a pretreatment method for anaerobic digestion of sludge, and there are few reports on anaerobic digestion pretreatment of feces, and the solid content rate used in existing low-temperature thermal hydrolysis processes is low (1% to 5% ), leading to the embarrassing situation that the increased gas production is not enough to make up for the additional energy consumption required by thermal hydrolysis, that is, the net gas production (the difference between biogas production capacity and thermal energy consumption) decreases instead

At present, there are few reports on low-temperature thermal hydrolysis with a solid content higher than 8%.

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