铁矿烧结中木炭及燃气替代焦粉的研究

Study on Replacement of Coke With Charcoal and Methane in Iron-Ore Sintering

焦粉和无烟煤是铁矿烧结中的常规燃料。使用生物质替代焦粉进行烧结可以显著缓解温室气体和污染物的排放压力。本文对不同木炭替代比例下(20%,40%和60%)的烧结特性进行了测试。结果显示木炭替代量达到60%时,烧结速度显著提高,烧结床内熔化温度保持时间大幅降低。其次,针对木炭替代焦粉烧结过程中出现的问题,采用燃气喷吹方法来延长熔化温度保持时间(DTMT),从而提高烧结矿强度。两种燃气喷吹方法(额外喷吹和等热值喷吹)均可以提高燃烧效率和烧结床层温度,延长DTMT并提高MQI,从而改善高生物质替代比例下铁矿石的烧结强度。

Coke breeze and anthracite are the traditional heat suppliers to the iron ore sintering process.Using biomass for replacement of coke breeze is an attractive technique for reducing emissions of greenhouse gas and gaseous pollutantsin the iron ore sintering process.In this paper,the primary fuel was coke breeze with 20%,40%,and 60%replacement of the calorific heat input with charcoal.Firstly,the effect of charcoal substitution rate on sintering performance was studied.The result indicated that the sintering performance was badly damaged at the charcoal substitution rate of60%.For example,duration time of melting temperature（DTMT） sharply decreased.Moreover,the influence of gaseous fuel injection method on improving sintering performance was also examined.Both extra methane injection and equivalent calorific heat methane injection methods were adopted in the present study.The test results showed that DTMT and MQI increased obviously.Thus,the sinter strength was improved by methane injection methods.