Progress and Prospect of Deep Recycling Technology for Incineration Fly Ash
Based on the generation mode and characteristics of municipal solid waste incineration fly ash,the inorganic chloride salts recovery and treatment technologies,calcium element separation and recovery technologies,heavy metal elements separation and extraction technologies of incineration fly ash were explored.The advantages and disadvantages of each technology were analyzed,and the latest resource utilization industrialization progress of incineration fly ash were summarized.According to the study,two widely accepted systems were low-temperature dioxin detoxification+washing+evaporation recovery of heavy metal-containing salt water+calcium component forming cement,and high-temperature sintering/melting for dioxin detoxification+salt and heavy metal volatilization recovery+calcium component forming pottery/glass.In both systems,dioxins could be decomposed effectively.Calcium could be recycled,but the added value was not high,and in the process of calcium recycling,attention should be paid to the long-term environmental risks caused by the total amount of heavy metals entering the environment.There was currently a lack of cost-effective resourcing of chloride components.In the future,more investigations should be focused on developing effective recycling of calcium and chloride in fly ash,and need more detailed technical guidance documents as theoretical support and design basis.