Study of flue gas emission behavior and oxygen-enriched intensification of double-layer sintering with ultra-high bed
In view of the problem of low strength of sintering product by double-layer sintering with ultra-high bed,oxygen-enriched method was used to intensify the double-layer sintering processes.The effects of oxygen-enriched concentration and fuel consumption on sintering indexes were studied,the mineral composition and microstructure of different sinters were analyzed,and the emission behaviors of O2,CO2 and CO in the sintering flue gas were identified.The results show that oxygen-enriched can significantly intensify the double-layer sintering processes with ultra-high bed and greatly improve the strength and yield of sinter.After the second ignition,the material layer is enriched with oxygen whose concentration is 25%,the yield,the tumbler strength,productivity and solid fuel consumption are 69.06%,66.40%,2.09 t/(m2∙h)and 53.79 kg/t,respectively,compared with the common double-layer sintering,the yield,tumbler strength and productivity are increased by 4.11%,7.73%and 0.18 t/(m2∙h),respectively,and the solid fuel consumption is reduced by 3.23 kg/t.The oxygen-enriched makes magnetite in sinter fully oxidized,and calcium ferrite especially needlelike calcium ferrite is massively generated,which makes the structure homogeneous and compact.Oxygen-enriched can increase the O2 content in sintering flue gas,solve the problem of oxygen-poor in the lower material layer,improve fuel combustion efficiency and reduce CO emission.
iron ore sinteringultra-high beddouble-layer sinteringoxygen-enrichedflue gasmineral structure