Method for synergistic treatment and harmless cyclic utilization of refuse fly ash by using cement kiln

Abstract

The invention relates to a method for synergistic treatment and harmless cyclic utilization of refuse fly ash by using a cement kiln. The method for synergistic treatment and harmless cyclic utilization of refuse fly ash by using thecement kiln comprises a three-stage washing desalination technology, a technology of removing heavy metals by coagulation and sedimentation, a membrane distillation concentration technology, a technology of removing slight trace carnallite and a triple-effect evaporation crystallization technology, wherein the three-stage washing desalination technology can remove heavy metals and chloride ions in the fly ash, and the fly ash which contains water and dioxin and the fly ash which contains less than 1% of chlorine ions enter the cement kiln and are incinerated at the temperature of above 1400 DEG C to turn into cement raw materials, and the dioxin is split at the temperature of above 800 DEG C; the technology of removing the heavy metals by coagulation and sedimentation can remove multiple metal ions in the fly ash, and precipitates are dried in advance and then enter the cement kiln to be incinerated; the membrane distillation concentration technology can remove the rest of chloride ions in a solution, and generated distilled water can be recycled; the technology of removing the slight trace carnallite can remove the slight trace carnallite, and heat energy can be recycled; and the triple-effect evaporation crystallization technologyevaporates and separates high salt content concentrated liquid to obtain industrial salt which is used for a paper making technology, snow-melting agents and chloro-alkali industries.

Description

Technical field: [0001] The invention relates to the field of processing technology of incineration fly ash, and more specifically relates to a method for co-processing garbage fly ash in a cement kiln and recycling and utilizing harmless resources. Background technique: [0002] With the development of social economy and the intensification of urbanization process, many large and medium-sized cities in my country are troubled by "garbage siege". There are three ways of waste disposal: landfill, incineration and composting. At present, landfill is the main method of waste disposal in my country, supplemented by composting and incineration, which will occupy a large amount of land resources. With the rise of land prices and the continuous improvement of urban environmental requirements, garbage landfill has become uneconomical and safe, and more and more cities have begun to consider garbage incineration. Incineration treatment can reduce the volume of urban garbage by 80-90...

AI Technical Summary

Problems solved by technology

On the one hand, the cost of fly ash disposal is high

On the other hand, due to the unregulated market, inadequate supervision and vicious competition, the "fly ash" is in a state of "flying randomly".

If fly ash cannot be disposed of safely, it will be a great hidden danger to the environment

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