Study On The Distribution Law Of Carbon And Dioxin And The Method Of Flotation Separation In Municipal Solid Waste Incineration Fly Ash

With the development of china’s economy and the growth of urban population,the amount of municipal solid waste is increasing year by year.Incineration has become the main method of harmless treatment of garbage,and it has also brought about the problem of huge and rapid growth of fly ash emissions.To lay the foundation for the resource utilization of waste fly ash partially replacing fly ash mixed with a small amount of premixed concrete,and to solve the problem of domestic waste incineration fly ash disposal.In this paper,the different particle size components and different density components of garbage fly ash was studied,as well as the distribution law of dioxins and the technical route of flotation decarbonization.After the domestic waste incineration fly ash is leached by the NH₄Cl solution,Na Cl,KCl,Ca Cl OH,Si Cl₄ and Ca（OH）₂ are dissolved,and Ca SO₄ is also partially dissolved due to the salt effect of the NH₄Cl solution.The proportion of Ca CO₃ and Si O₂ is increased.The mass loss of ash and secondary ammonium washing ash are55.74%and 66.49%respectively.Ammonium washing and water washing will not affect the carbon content and dioxin fingerprint characteristics.Using the BXF cyclone particle size analyzer,the primary ammonium ash washing cyclone is divided into particle size greater than 53μm,particle size 53-40μm,particle size 40-30μm,particle size 30-20μm,particle size 20-10μm,There are 7 particle size grades with a particle size of 10-8μm and a particle size of less than 8μm.The carbon content of each particle size grade is relatively even.The toxic equivalent concentration of dioxin increases with the decrease of the particle size.The carbon distribution rate and dioxin I-The distribution rate of TEQ is quite different.The distribution rate of carbon in the component with a particle size of less than 10μm is 43.13%,but the distribution rate of dioxin I-TEQ is as high as 88.19%.Dioxin is easily concentrated in the particle size less than 10μm.Use sodium polytungstate heavy solution to divide the secondary ammonium washing ash float into a density less than 1.8 g/cm³,a density of 1.8-2.3 g/cm³,a density of 2.3-2.5 g/cm³,a density of 2.5-2.7 g/cm³,and a density greater than 2.7 g/cm³ There are 5 density levels in g/cm³.It can be determined by SEM and EDS that the components with a density of less than 1.8 g/cm³ are mainly composed of carbon particles of different shapes and hollow glass spheres.As the density increases,the carbon particles gradually decrease.The high-density medium carbon particles are wrapped by inorganic minerals,resulting in higher density;as the density increases,the LOI of each density level decreases,and the particle size decreases.The carbon content and the dioxin equivalent concentration show a downward trend,and the density is less than 2.3 g/cm³ The distribution rate of the component carbon is 84.77%,but the distribution rate of dioxin I-TEQ is 51.04%,and 48.96%of the dioxin in the fly ash is distributed in the low-carbon mineral components with a density greater than 2.3 g/cm³.Kerosene and sec-octanol are used as collectors and foaming agents,respectively.The flotation effect is the best under the conditions of 10000 g/t and 2500 g/t,aeration rate of 0.20 m³/h,the flotation effect is the best under the condition of 60 g/L slurry concentration,the yields of refined carbon and tailings are 14.69%and 85.31%,respectively,the ignition loss is 40.72%,12.42%,the carbon content is 26.10%,0.84%,and the carbon removal rate is 84.25%.