Pre-processing technology for anaerobic fermentation of kitchen waste

Abstract

The invention relates to the field of treatment of kitchen waste, in particular to a pre-processing method for anaerobic fermentation of kitchen waste. The pre-processing method for anaerobic fermentation of kitchen waste comprises steps as follows: 1): transferring the kitchen waste into a receiving bucket of a receiving and conveying system, and then conveying to a crushing and separating system by virtue of a longitudinal shaftless screw conveyor, a transverse shaftless screw conveyor and a lifting screw conveyor which are arranged at the bottom of the receiving bucket; 2) separating hard substances from the kitchen waste by virtue of a crushing and separating integrated machine in the crushing and separating system, and processing the kitchen waste to obtain pulped waste, and then buffering the pulped waste in a buffering tank of the system; and 3) conveying the pulped waste buffered in step 2) into a sand removing system, and separating the heavy substances, and then feeding into an anaerobic fermentation device. The pre-processing method provided by the invention is short in technological process, high in processing efficiency, capable of effectively removing various impurities which bring influence to the anaerobic fermentation system and able to sort the organic waste from the kitchen waste to the maximum.

Description

technical field [0001] The invention relates to the field of kitchen waste treatment, in particular to a pretreatment method for anaerobic fermentation of kitchen waste. Background technique [0002] Food waste refers to food waste and food residues in families, schools, public canteens of government agencies and the catering industry. It is the main component of municipal solid waste. It has the characteristics of high content and rich nutrient elements, and has great recycling value. [0003] Previously, food waste was mainly used as feed for pigs in the suburbs of cities. Due to its complicated sources, it is very likely to cause disease transmission, and it has been banned by the government for feeding. In daily life, residents usually mix kitchen waste with domestic waste and send it to garbage collection points through plastic bags, which changes the composition and characteristics of urban domestic waste. During the storage, collection, transfer and landfill process...

AI Technical Summary

Problems solved by technology

During the storage, collection, transfer and landfill process of food waste, due to its high water content and organic matter content, it is easy to rot, smell and breed mosquitoes in a short period of time, which greatly pollutes the surrounding environment.

In addition, the disposal methods of municipal waste usually include incineration and landfill. If municipal solid waste is incinerated, since the moisture content of kitchen waste is often as high as about 90%, the calorific value is 2100-3100kJ / kg, and it is incinerated together with other waste , not only cannot meet the calorific value requirements of waste incineration power generation (that is, more than 5000kJ / kg), but will cause the incinerator to burn insufficiently and produce dioxins; High content should not be handled

Moreover, incineration and landfill will lead to a large amount of waste of organic matter, so it is necessary to treat food waste separately

[0004] One of the main treatment technologies of existing food waste is to produce combustible gas by anaerobic microbial fermentation of food waste, but anaerobic fermentation has high requirements for fermentation substrates, and food waste contains a large amount of non-organic waste. Treatment and removal will have adverse effects on anaerobic fermentation and greatly reduce the efficiency of anaerobic fermentation

Patent CN101632996A provides a pretreatment process for kitchen waste, which can conduct preliminary solid-liquid separation of garbage and sort out organic waste. However, this process does not separate a large number of sand and gravel particles contained in kitchen waste, and Sand and gravel can block the pipeline of anaerobic fermentation equipment, which is very harmful to anaerobic fermentation

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