碱性金属氧化物对焦粉灰熔融特性的影响OA

Coke powder is a solid waste produced in coking enterprises,and utilizing coke powder to produce synthesis gas can reduce cost and improve efficiency.For entrained flow gasification,the ash melting characteristics need to be focused on.Alkaline oxides CaO,MgO and Fe2O3 were used as additives,and the ash fusion temperatures were measured by an ash fusion point determination meter under weak reducing atmosphere.The macroscopic morphologies and microscopic morphologies of the quenched ashes were observed,and the causes of the mass changes of the ashes were investigated by XRF and TG,and the mineral compositions of the ashes were analyzed by XRD and FactSage software.The effects of additives on the ash melting characteristics were investigated,and the reasons for the decrease of ash melting temperature were explored.The results show that the ash flow temperature of coke powder is 1345℃,and the fluxing effects of CaO and MgO are significant,while the fluxing effect of Fe2O3 is not obvious.When wCaO=3%,the ash flow temperature decreases to 1217℃,and When wMgO=5%,the ash flow temperature decreases to 1212℃.The main reason for the decrease in mass of ash during the heating process is the decomposition of anhydrite(CaSO4),which affects the mineral compositions.The main reason for the decrease of ash melting temperature is the low-temperature melting of wollastonite(CaSiO3),anorthite(CaAl2Si2O8)and gehlenite(Ca2Al2SiO7),while CaO and MgO can significantly regulate the contents(mass fraction)of CaAl2Si2O8 and Ca2Al2SiO7.FactSage software calculations show that the liquid phase formation temperatures of the ashes decrease due to CaO and MgO.When wCaO=3%,the fluxing effect is relatively better,which is consistent with the experimental results.