高磷鲕状赤铁矿直接还原同步脱磷研究

Study of Direct Reduction and Synchronous Dephosphorization for High-phosphorus Oolitic Hematite

对含铁品位为43.58%、含磷0.83%的鄂西某宁乡式高磷鲕状赤铁矿进行了直接还原焙烧脱磷试验研究。研究了焙烧温度、还原剂用量、焙烧时间、脱磷剂用量对直接还原铁指标的影响。在还原剂用量17.5%,TS用量50%,NCP用量2.5%,焙烧时间60 min,一段磨矿粒度为-0.074 mm粒级占89.56%,磁选磁场强度为87.58 kA/m;二段磨矿粒度为-0.025 mm粒级占100%,磁选磁场强度为87.58 kA/m时可得到铁品位91.58%,回收率84.96%,磷品位0.049%的直接还原铁磁选精矿。

Experimental studies on direct reduction roasting and synchronous dephosphorizaton were conducted for some Ningxiang type high-phosphorus oolitic hematite with iron content of 43.58%,phosphorus content of 0.83% in west of Hubei Province.The effects of roasting temperature,the reductant dosage,roasting time and dephosphorizer dosage on the index of DRI（Direct Reduced Iron） were investigated.Iron concentrates with iron grade of 91.58%,recovery of 84.96% and phosphorus grade of 0.049% can be obtained through direct reduction roasting and magnetic separation under conditions as follows： reductant dosage of 17.5%,TS dosage of 50%,NCP dosage of 2.5%,roasting time of 60 min,first-stage grinding size of 89.56%-0.074 mm with magnetic field intensity of 87.58 kA/m,second-stage grinding size of 100%-0.025 mm with magnetic field intensity of 87.58 kA/m.