Curing agent for waste incineration fly ash

Abstract

The invention relates to a curing agent for waste incineration fly ash. Every 100 parts of the curing agent is prepared by mixing 80-95 parts of pyrite and 5-20 parts of calcium carbonate powder. The curing agent for the waste incineration fly ash involved in the invention is prepared by compounding the pyrite and the calcium carbonate powder, and the curing agent prepared according to the proportion has good curing effects ; by using the curing agent for treating the waste incineration fly ash, hazardous substances (including heavy metal, arsenic, fluorine and the like) in the waste fly ash can be effectively cured, the curing age is short, the curing cost is largely reduced, the curing agent has good stability, the problem of leaching of the hazardous substances after curing does not exist, and other high-concentration wastes are not produced either.

Description

technical field [0001] The invention relates to environmental protection technology, in particular to a garbage incineration fly ash curing agent. Background technique [0002] As the centralized incineration method has gradually become the main method of municipal solid waste treatment in my country, the safe disposal and utilization of incineration fly ash has also become a common concern of scholars. Due to the impact of various environmental factors during the landfill process, heavy metals in waste incineration fly ash may migrate and transform. Therefore, how to deal with incineration fly ash has attracted more and more attention with the development of society. Stabilization and fly ash solidification must be carried out before the final disposal of incineration fly ash, because incineration fly ash contains heavy metals such as lead and cadmium with high leaching concentrations. Of course, the incineration fly ash can also be transported to a special hazardous waste...

AI Technical Summary

Problems solved by technology

[0004] 1. Cement curing technology: Cement curing is a method of mixing fly ash and cement in a certain proportion and adding an appropriate amount of water to make them solidify; the curing mechanism is in the process of cement hydration, through adsorption, chemical absorption, and sedimentation , ion exchange, passivation and other methods, heavy metals finally stay in the form of hydroxides or complexes on the surface of hydrated silicate colloid C-S-H formed by cement curing, and the addition of cement also provides an alkaline environment for heavy metals , which inhibits the infiltration of heavy metals in fly ash; cement-solidified fly ash technology is a relatively mature hazardous waste treatment technology, which has obvious advantages in terms of economy and operability, but the amount of cement used is high, generally between 20 and 30%, resulting in a high compatibilization rate of the cured body. Over time, some toxic substances in the cured body may gradually dissolve, posing a long-term and potential threat to the environment

[0005] 2. Melting and solidifying technology: The melting and solidifying technology is mainly to mix fly ash and fine glass, after mixing and granulating, melting at a high temperature of 1000-1400 ° C, usually about 30 minutes (melting time depends on the nature of fly ash After the physical and chemical state of the fly ash has changed, cool it down to solidify it to form a glass solidified body. With the help of the dense crystal structure of the glass body, the stability of the heavy metal is ensured; the fusion solidification technology has a high capacity reduction rate for the residue and a good solidification effect , but the fatal disadvantage is that some toxic substances will be volatilized, and exhaust gas treatment measures must be taken. The system is more complicated and the operating cost is high.

Using the above-mentioned agents to treat fly ash can generally achieve better results. This method has the advantages of simple treatment process and less investment in equipment, but the disadvantage is that it will produce high-concentration inorganic salt wastewater, which needs further treatment. Moreover, the solidified part Toxic substances may dissolve gradually, presenting a long-term, potential threat to the environment

[0007] In the above-mentioned prior art, the pertinence to heavy metals is not high, so the treatment agent and treatment method of waste incineration fly ash urgently need to be improved, and a more effective and reasonable treatment agent for waste incineration fly ash needs to be developed

Images