Method for processing sludge and kitchen wastes

Abstract

The invention relates to a method for processing sludge and kitchen wastes. The method comprises the following steps: by utilizing sludge and kitchen wastes as principal raw materials; separating waste oil from kitchen wastes to be taken as the raw material of fuel or bioplastics; taking biological fuel gas, which takes methane as main material and is generated through fermentation, as an external fuel supply; absorbing the nutrient in biogas slurry by the charcoal generated through pyrolysis and then taking the charcoal as a charcoal fertilizer. The method for processing sludge and kitchen wastes provided by the invention meets the increasingly urgent requirement of processing the sludge and kitchen wastes in China at present; the method can be used for efficiently solving the problems of separately processing sludge and kitchen wastes; the classification and valuable utilization of by-products are realized; various by-products are low-carbon high-efficient cleanly utilized; the purposes of best use, energy conservation, environment protection and cost lowering are achieved; the method has excellent economic benefit and environmental benefit.

Description

technical field [0001] The invention relates to the field of comprehensive utilization of kitchen waste and sludge resources, in particular to a treatment method for sludge and kitchen waste. Background technique [0002] With the continuous expansion of the scale and number of urban sewage treatment plants, the amount of sludge generated in my country has increased rapidly, and it is predicted that it will reach 40 million tons per year (calculated with a moisture content of 80%). A large amount of wet sludge is randomly transported, simply landfilled or piled up (accounting for about 60% of the disposal volume), which has caused many cities to be "sieged by poisonous mud", and the social problems caused by this have become increasingly urgent. Landfilling can only be used as a short-term control measure due to the gradual reduction of landfill sites and strong opposition from surrounding residents due to environmental pollution. Developed countries have gone through a dev...

AI Technical Summary

Problems solved by technology

[0006] The problem to be solved by the present invention is to overcome the deficiencies in the prior art. In view of the low organic matter content of the above-mentioned sludge, the common problems of low carbon-nitrogen ratio and low gas production rate in anaerobic digestion alone, and the problems of food waste In anaerobic digestion alone, the carbon-nitrogen ratio is high, and the hydrolysis speed is too fast, resulting in low pH value, low nitrogen content, high salinity, acid inhibition and ammonia nitrogen inhibition, and provides a treatment for sludge and kitchen waste The method overcomes the shortcomings of the existing process of collaborative resource utilization of kitchen waste and sludge, converts food waste and sludge into biogas and biochar fertilizer, and realizes efficient utilization of food waste and sludge collaborative resource, low-carbon , Efficient and clean use of various by-products to achieve the goal of making the best use of everything, saving energy and environmental protection, and reducing costs

[0008] Due to the low content of organic matter in sludge, there are generally problems of low carbon-nitrogen ratio and low gas production rate in anaerobic digestion alone, while the carbon-nitrogen ratio is high in anaerobic digestion of kitchen waste alone, and the hydrolysis rate is too fast, resulting in a low pH value. , low nitrogen content, high salinity, acid inhibition and ammonia nitrogen inhibition are prone to problems, so the sludge and kitchen waste treatment method of the present invention mixes sludge hydrothermal liquid with kitchen waste separation water Fermentation is beneficial to complement the shortcomings of sludge and kitchen waste in anaerobic digestion alone, which is conducive to improving system operation stability, organic matter removal effect and gas production efficiency, and reducing operating costs

Images