Garbage incineration fly ash filter cake modification method

Abstract

The invention discloses a garbage incineration fly ash filter cake modification method including: first, adding fly ash, sodium carbonate, coal ash and water into a first-stage water washing stirring tank for water washing for three times, using a vacuum filter for solid-liquid separation of filtrate and filter cake after each time of water washing; wherein filtrate separated by first time solid-liquid separation is sent into a sewage tank for subsequent wastewater treatment; the second time and third time solid-liquid separated filtrates are respectively used as the first time and second time water washing water; the third time water washing is clear water washing. The third time solid-liquid separated filter cake is a modified fly ash filter cake, due to the less looseness and smaller viscosity, the feed conveying is smooth, drying machine material attachment is reduced, the strength of material blocks formed during drying of the filter cake is small, wall scrapping is easy, and scattering is smooth, the fly ash filter cake drying process can be performed normally, the problems existed in the real engineering can be solved, and the cement kiln co processing garbage incineration fly ash technology can be improved.

Description

technical field [0001] The invention relates to the technical field of washing waste incineration fly ash, in particular to a method for modifying a filter cake of waste incineration fly ash. technical background [0002] In recent years, the waste incineration power generation projects that have emerged at home and abroad have contributed to the harmlessness, reduction, and resource utilization of municipal solid waste. However, waste incineration fly ash contains pollutants such as heavy metals and dioxins, which are highly concerned by environmental protection departments in various countries. In my country, the "National List of Hazardous Wastes" clearly stipulates that fly ash from domestic waste incineration is hazardous waste. Therefore, how to deal with waste incineration fly ash and develop treatment technology has become one of the research hotspots in the field of environmental protection in recent years. [0003] Since waste incineration fly ash contains a lot ...

AI Technical Summary

Problems solved by technology

This method uses water washing technology to pretreat the fly ash, which effectively reduces the harmful components in the fly ash and greatly improves the ability of the cement kiln to co-process the fly ash. However, in actual engineering operation, due to the High CaO content, small particle size, and large specific surface area make the filter cake obtained through the solid-liquid separation of the vacuum filter tightly agglomerated and highly viscous, resulting in blockage of the feed conveying device of the dryer and serious wall formation inside the dryer. Affected the drying process of fly ash filter cake

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