| In this study,the particle size and elemental composition of arsenic sulfide residue was analyzed.The desulfurization,dearsenization and resource utilization of complex agglomerated solid waste containing arsenic were studied in the following six stages: drying,vacuum drying,melting,vacuum desulfurization,vacuum dearsenization and oxidation,and the effects of time,temperature and other factors on dehydration rate and sulfur and arsenic content changes in each stage were investigated.The experimental results show that:(1)Arsenic sulfide residue particles were small,with the particle size below10 microns accounting for 80%,and the average particle size was 3.5 microns.Arsenic sulfide slag usually appears in the form of amorphous and polycrystalline polymers,and often condenses into a group.Its basic elements include S,As,Cu,Na,Pb,Zn,etc.(2)Arsenic sulfide residue was dehydrated by general drying.The results showed that the best drying conditions were 90 ℃ and 5 h,and the dehydration rate reached 20.98 %.The best drying conditions for sample preparation under vacuum conditions were 120 ℃ and 3 h,at which time the dehydration rate reached 14.31 %.(3)The results of desulfurization experiments show that the desulfurization effect becomes better and better with the increase of temperature from 350 ℃ to500 ℃ in the same time,but it is better to set the desulfurization temperature at450 ℃,at which the separation of arsenic and sulfur is relatively good.When the temperature of dearsening is 600 ℃,the best effect is achieved,and the dearsening time is between 2 and 6 hours.There is little difference in the effect of arsenic precipitation,so 3 hours is enough.(4)The content of S and As in arsenic sulfide residue can be effectively degraded after desulfurization and arsenic removal process,which highlights the value of valuable metals in the residue,thus greatly promoting the resource utilization value of arsenic sulfide residue. |
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