红土镍矿双层配碳烧结性能及烟气污染物排放的变化

Changes in double-layer sintering performance and flue gas pollutant emission of laterite nickel ore

为开发利用储量丰富、价格低廉的红土镍矿,本文在不提高总配碳量的条件下,通过改变上下料层混合料中固体燃料的占比,进行红土镍矿双层配碳烧结试验,研究新工艺的烧结性能及其对混合料制粒性能的影响,并分析烧结烟气中污染物的变化规律。结果表明:双层配碳烧结可使上下料层热量分布更均匀,降低下料层的过熔现象,改善制粒效果,增强烧结过程料层透气性,使无烟煤燃烧更加充分,并大幅提高烧结性能;与基准试验相比,两组试验烧结矿的成品率分别提高7.99%和10.40%,转鼓强度分别提高6.77%和5.34%,利用系数分别提高0.29、0.20 t/(m^(2)·h),固体燃料消耗分别降低15.80、22.59 kg/t,烧结矿性能均有大幅度提高;双层配碳烧结有助于减少污染物排放,其中NO_(x)和SO_(2)排放量均减少31.14%和61.35%,有利于环境保护。

In order to develop and utilize laterite nickel ore with abundant reserves and low price,by changing the proportion of solid fuel in the upper and lower layer compound,the double-layer sintering test of laterite nickel ore is carried out without increasing the total carbon distribution,the sintering performance of the new process and its influence on the granulation performance of the mixture are studied,and the change law of pollutants in the sintering flue gas is analyzed.The results show that double-layer sintering can make the heat distribution of the upper and lower material layers more uniform,reduce the overmelting phenomenon of the lower material layer,improve the granulation effect,enhance the air permeability of the material layer in the sintering process,make the anthracite combustion more sufficient,and greatly improve the sintering performance.Compared with the benchmark test,the yield of the two groups of experimental sinter is increased by 7.99%and 10.40%,respectively,the tumbler strength is increased by 6.77%and 5.34%,respectively,the utilization coefficient is increased by 0.29 and 0.20(m^(2)·h),respectively,the solid fuel consumption is decreased by 15.80 and 22.59 kg/t,respectively,and the sinter performance is greatly improved.Double-layer sintering helps to reduce pollutant emissions,among which NO_(x)and SO_(2)emissions are reduced by 31.14%and 61.35%,which is conducive to environmental protection.