Treatment method for full-amount resource utilization of municipal wet garbage

Abstract

The invention relates to a treatment method for full-amount resource utilization of municipal wet garbage, which comprises the following steps of (1) pretreating municipal wet garbage to prepare slurry, and carrying out anaerobic fermentation to generate biogas and a fermentation mixture, and (2) dehydrating the obtained fermentation mixture to obtain biogas slurry and biogas residues, drying the biogas residues, pyrolyzing and carbonizing to obtain biochar and pyrolysis byproducts, refluxing one part of the biogas slurry into the slurry in the step (1), and concentrating the other part of the biogas slurry to be used as an organic fertilizer for resource utilization. Compared with the prior art, resource utilization of all products obtained after anaerobic fermentation of the wet garbage can be achieved, meanwhile, it is guaranteed that heat in the system is self-sufficient, and the carbon sequestration and emission reduction benefits are improved.

Description

technical field [0001] The invention belongs to the technical field of organic solid waste environmental protection, and relates to a treatment method for full resource utilization of municipal wet waste. Background technique [0002] In recent years, with the gradual implementation of waste classification across the country, the demand for wet waste treatment has become more and more urgent. Shanghai defines wet waste as "food waste + kitchen waste + market fruit and vegetable waste" (that is, municipal wet waste ), mainly all degradable organic wastes produced by urban residents in their daily lives. [0003] At present, a number of biogas projects have been built in China that use kitchen waste or kitchen waste as raw materials. After anaerobic fermentation of wet waste, biogas can be generated, which can be used for power generation and grid supply, and can also be directly used for heating. However, even after the solid-liquid separation of the fermented product, there...

AI Technical Summary

Problems solved by technology

However, even after the solid-liquid separation of the fermented product, there is still a large amount of biogas residue that has no place to be consumed. At present, the conventional methods of biogas residue disposal mainly include: (1) Co-processing, which is suitable for projects with nearby incineration sites. The generated biogas residue Direct incineration, but this path has not achieved resource utilization, and faces high disposal costs; (2) Fermentation composting, suitable for raw materials of agricultural organic wastes, currently no bio-organic fertilizers are made from wet wastes Due to concerns about food and food safety, the agricultural sector temporarily does not allow organic fertilizers produced from kitchen and kitchen waste to be returned to the field; (3) Insect breeding can effectively use high-protein substances in organic waste, However, there are still practical problems such as the long process chain and the high risk of breeding.

As a result, the terminal resource utilization of municipal wet waste is greatly restricted, and the full resource utilization of wet waste has become an urgent problem to be solved

[0004] In addition, the resource utilization of biogas slurry is also facing the same problem. On the one hand, the output of biogas slurry is large, there is not enough land to absorb it, and land fertilization is seasonal; on the other hand, when the nutrients in the biogas slurry are used as When pollutants are removed, the possibility of resource utilization of nutrients is also greatly reduced

Images