Research On The Influence Of Municipal Solid Waste Incineration Fly Ash Alkali Metals On Leaching Toxicity And Resource Utilization

With the acceleration of urbanization,the amount of municipal solid waste is continuously increasing,and the composition of waste is also very complex.The domestic waste incineration power generation treatment has the advantages of significant reduction,less land resource occupation and effective use of energy,and has gradually become the mainstream way of domestic waste disposal in my country.The fly ash produced after waste incineration contains a large number of harmful pollutants.There are few studies on the correlation and interaction between the leaching toxicity of heavy metals in the fly ash and other key components.The leaching characteristics of the pollutants in the waste incineration fly ash and its The law of influence,the research on the harmless disposal and resource utilization of waste incineration fly ash is extremely important for the realization of the harmless and resourceful disposal of waste incineration fly ash and the protection of the ecological environment.This paper takes domestic waste incineration fly ash as the research object,and uses ICP,XRD,XRF,and SEM analysis methods to carry out a systematic study on the element composition,p Hase composition,microscopic morp Hology and leaching toxicity of domestic waste incineration fly ash;research on Ca O,Na Cl,KCl and other components on the leaching behavior of heavy metal Pb.Studies have shown that with the increase of Ca O content in fly ash,the leaching toxicity of Pb in fly ash first decreases and then increases;with the increase of Na Cl and KCl,the leaching toxicity of Pb gradually increases.The water elution process is used to study the dechlorination characteristics of waste incineration fly ash.The results show that water washing can effectively remove soluble chlorides(Na Cl,KCl,Ca Cl OH)in fly ash,etc.When the solid-liquid ratio is1:10,water washing When the time is 10 min and the oscillation rate is 110r/min,the removal rate of chloride ions in the fly ash reaches more than 95%.The feasibility and product performance of cement concrete prepared by adding washed waste fly ash after washing treatment were studied.The results showed that when cement mortar was mixed with washing pretreated waste fly ash,its compressive strength and flexural strength were both equal.When the water washing pretreatment waste fly ash content is 10%,the compressive strength and flexural strength of the product reach the highest,and reach the strength requirements of ordinary Portland P.O42.5 cement products;when cement concrete When mixed with waste fly ash that has undergone high temperature treatment,the early strength of concrete products is slightly reduced.Under the conditions of 20% of waste fly ash sintered product and curing time of 28 days,the compressive strength of concrete products can reach C30 The requirements of concrete,the flexural strength is slightly lower than that of C30concrete;the results of the leaching toxicity analysis of the products of the two resource recycling methods show that the heavy metal leaching toxicity of the concrete products prepared with fly ash is far lower than the national standard value,The environmental safety is good,and a new way is proposed for the resource utilization of waste incineration fly ash.