Solidification and Stabilization Process of Fly Ash

Abstract

The invention discloses a process for solidifying and stabilizing fly ash, which comprises the following steps: mixing fly ash, edetate disodium solution, congeal, fine sand and asbestos according to the ratio of 100:2 to 6:3 to 7:2 Mix and stir at a mass ratio of ~5:1~4, and complete the curing and stabilization treatment after molding and curing. The process of the present invention stabilizes the lead in the fly ash in a targeted manner, effectively improves the strength of the solidified monomer of the fly ash, improves the strength and stability of the fly ash landfill pile, and prolongs the toxic leaching of the fly ash To prevent the fly ash solidified body from loosening after soaking in water, and ensure the safety of the fly ash landfill pile.

Description

technical field [0001] The invention belongs to the field of waste incineration treatment, and relates to a process for solidifying and stabilizing fly ash, in particular to a process for solidifying and stabilizing fly ash by changing raw material components and ratios. Background technique [0002] Waste incineration fly ash refers to the extremely fine particles collected by various pollution control equipment during the flue gas treatment process after the domestic waste is incinerated. The fly ash is mostly powdery, the color is generally gray, and the particle size is generally 40-60 μm. The bulk density is 0.5~1.0g / cm 3 , The naturally accumulated porosity is higher, and it has a higher moisture absorption capacity. Because the garbage contains high plastic content, the lead content of fly ash produced by incineration generally exceeds the requirements of national regulations, and the content of other heavy metals basically meets the requirements of national regulati...

AI Technical Summary

Problems solved by technology

[0003] At present, the country is very strict on the pollution control of fly ash, so the fly ash produced by garbage incineration must be solidified and stabilized to make the indicators meet the national standards before it can be landfilled. The current solidification and stabilization process is mainly through Add a certain proportion of cement, chelating agent, and water to the fly ash, and then mix and stir to initially form a structure similar to a solidified body. Although this structure can be molded and has a certain strength, the auxiliary materials used in this commonly used process are uniform. It is a powder or water solution, and there is no aggregate in the overall structure for support, nor is it solidified in a way similar to "reinforcing", so when it is landfilled to a certain height during on-site landfill disposal, it is very easy under the action of the upper layer. The fly ash pile will be overloaded, and the formed fly ash solidified body will be deformed, cracked, etc., and the bottom of the fly ash pile will easily loosen, settle or slide after being immersed in water, which poses a hidden danger to the safety and stability of the overall pile. Gradually increasing, security risks are difficult to guarantee

On the other hand, because the chelating agents that can be purchased in domestic and foreign markets are aimed at stabilizing all indicators required by the regulations, rather than passivating lead in fly ash in a targeted manner, the composition of chelating agents is complex and the price is high