High-efficiency, low-cost and harmless disposal method and system for fly ash combined with mechanochemical and water washing

Abstract

The invention relates to the field of harmless fly ash treating, and provides a method and system for treating fly ash in a manner combining mechanochemistry and washing, with characteristics of high efficiency, low cost and zero harm. The system comprises a feed bin, a horizontal roller type ball mill, a stirring kettle and a plate-and-frame filter press, wherein the bottom of the feed bin is connected to a feed opening of the horizontal roller type ball mill; stainless steel milling balls are placed in a closed barrel body of the horizontal roller type ball mill; two ends of a discharge pipeline are connected to the bottom of the horizontal roller type ball mill and the upper part of the stirring kettle respectively; the upper part of the stirring kettle is connected with a water inlet pipeline, and the bottom of the stirring kettle is connected to the plate-and-frame filter press. According to the method and the system which are disclosed by the invention, the heavy metal solidification, the dioxin degradation and the chlorine removal of the fly ash can be realized at the same time in high efficiency, the treated fly ash is thoroughly harmless and has conditions of resource utilization, and the heavy metal solidification rate of the treated fly ash is more than 70%; an additive is not additionally added, so that the treating cost is low; the technological process is simple, the reaction conditions are mild, the treating process is environment friendly, and harmful by-products are not generated; the equipment investing cost and the operating cost are low, the treating effects are significant, and the technological process is simple to realize.

Description

technical field [0001] The invention relates to the harmless disposal and resource utilization of municipal solid waste incineration fly ash, and focuses on a high-efficiency and low-cost fly ash collaborative solidification of heavy metals, dioxin degradation and chlorine removal disposal technology. Background technique [0002] With the continuous rapid growth of my country's economy, the annual output of municipal solid waste in my country has increased rapidly, and the total volume of removal and transportation in 2012 reached 170.81 million tons. Waste incineration power generation is an efficient treatment method with a high degree of harmlessness, large volume reduction and maximum energy recovery. However, the heavy metals and dioxins in the flue gas produced by domestic waste incineration have been purified, and more than 90% of them are trapped in fly ash. Harmless disposal. At present, the disposal of fly ash has the following problems: the amount of fly ash pr...

AI Technical Summary

Problems solved by technology

[0004] 1. Although cement solidification can inhibit the infiltration of heavy metals in fly ash, the volume of fly ash after solidification increases, which is not conducive to later transportation and landfill;

[0005] 2. The fly ash agglomerated after cement solidification treatment does not meet the conditions for resource utilization;

[0006] 3. Cement solidification treatment cannot degrade dioxins in fly ash, and the long-term stability of calcium silicate colloid, the key structure of solidified heavy metals, is not good, which greatly increases the potential threat of solidified fly ash to the environment;

[0007] 4. Cement kiln co-processing is the main way of resource utilization of fly ash at present, but the amount of fly ash mixed is only 1%, which leads to the existing cement kiln can only achieve limited resource utilization of fly ash, which is difficult to meet the output Disposal of large fly ash

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