Innocent treatment method and apparatus for refuse burning flyash

Abstract

The invention proposes a method for the innocent treatment of refuse burning fly ash. The method comprises the following steps: prewetting; pulping: mixing and stirring the fly ash and water in the proportion of 1:2 to 1: 20 to form ash slurry; water washing and precipitation: dissolving the soluble salts in the fly ash; modification through a reagent; concentration for reducing the water content of the ash slurry to 70 to 90 percent; dehydration for reducing the water content of the ash slurry to below 35 percent; water treatment: charging CO2 or acid to make the strongly basic supernatant with the pH value as high as 11 to 12 become the neutral water quality with the pH value of 6.0 to 8.5; flocculant addition for catching tiny particles and speeding up the precipitation process; cement preparation: heating up the fly ash end product in a cement rotary kiln to 1,000 to 1,450 DEG C, and decomposing dioxin and inhibiting the regeneration of the dioxin at the low temperature; and increase of the boiling point of heavy metals for passivating the volatility.

Description

technical field [0001] The invention relates to the technical field of environmental engineering, in particular to a method and a device for resourceful and harmless treatment of domestic waste incineration fly ash. Background technique [0002] Developing a circular economy and building a resource-conserving and environment-friendly society are the country's basic requirements for the cement industry and resource- and energy-intensive industries to transform their economic growth patterns. my country's cement output increased from 597 million tons in 2000 to 1.064 billion tons in 2005, with an average annual growth rate of 12.3%. [0003] With the continuous advancement of urbanization, the output of domestic waste is increasing. Now, incineration is one of the main ways to deal with garbage all over the world, and with the development of economy, incineration will show unprecedented advantages. Waste incineration produces fly ash, the main chemical components of fly ash ...

AI Technical Summary

Problems solved by technology

However, the existing technology is difficult to stably control the chlorine content in the finished fly ash

Excessive chlorine content will not only damage the quality of cement, but also cause blockage during cement burning

[0014] (2) The heavy metals in the fly ash will gasify at high temperature and be discharged into the atmosphere with the tail gas, causing pollution to the atmosphere

[0015] (3) Dioxin in fly ash is volatile at high temperature, how to effectively control dioxin pollution is also a very critical technical issue

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