Anaerobic digestion treatment method and system of kitchen waste

Abstract

The invention provides an anaerobic digestion treatment system and method of kitchen waste. The system comprises a first biological reactor in a start-up period, a second biological reactor in an active period, a third biological reactor in a decomposed period, a first digested effluent tank, a second digested effluent tank, a third digested effluent tank, a first pump, a second pump and a third pump, wherein a digested effluent outlet at the bottom of the first biological reactor is connected with a digested effluent inlet / outlet at the upper end of the first digested effluent tank; a digested effluent outlet at the bottom of the second biological reactor is connected with a digested effluent inlet / outlet at the upper end of the second digested effluent tank; digested effluent in the second digested effluent tank is conveyed to the second biological reactor through the second pump; a digested effluent outlet at the bottom of the third biological reactor is connected with a digested effluent inlet / outlet at the upper end of the third digested effluent tank; and digested effluent in the third digested effluent tank flows back to the first biological reactor through the third pump. By implementing the system and method, the technical problems of long cycle, low gas production rate, high salt content and inhibition of VFA (Volatile Fatty Acid) accumulation and ammonia nitrogen accumulation on gas production rate in the conventional kitchen waste anaerobic digestion process can be solved.

Description

technical field [0001] The invention relates to the field of environmental protection technology and the field of new energy development and utilization, in particular to a method and system for anaerobic digestion of kitchen waste. Background technique [0002] Food waste has the characteristics of high moisture, organic matter, oil and salt content, perishable, and rich nutrients. It is the main component of urban domestic waste in my country. Statistics show that in 2007, the national food waste was about 90 million tons, accounting for 31% of the total urban domestic waste in my country. The daily output of food waste in Beijing, Shanghai and other big cities exceeded 1,000 tons. Most of the food waste generated is sold to farms on the outskirts of the city to raise pigs directly, while the rest is disposed of mainly by landfill or incineration by relevant units. The degree of resource utilization of food waste is very low. [0003] The high content of organic matter in...

AI Technical Summary

Problems solved by technology

In addition, the high salinity of the food waste itself will cause the moisture in the microorganisms to leak out, so that the activity of the methanogenic microorganisms will decrease or even die. The higher the salt concentration, the stronger the toxicity

Studies have shown that methanogenic microorganisms are sensitive to Na + Very sensitive when Na + When the concentration is greater than 5000 mg / L, it will have an adverse effect on the final methane conversion

In addition, due to the characteristics of the anaerobic microbial flora, the start-up time of the anaerobic bioreactor is long, even as long as more than half a year, which seriously affects the resource utilization of kitchen waste

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