(中南大学 冶金科学与工程学院，长沙 410083)
摘 要: 在氯化剂CaCl2·2H2O的加入量为原矿质量的8%(以氯计)、还原剂焦炭加入量为原矿质量的6%及升温速率为5 ℃/min的条件下，对菲律宾红土镍矿进行氯化离析；采用TG-DTA和XRD研究菲律宾红土镍矿氯化离析升温至1 000 ℃及冷却过程中的物相转变。结果表明：红土镍矿中的氧化亚铁在700 ℃开始进入蛇纹石中，形成富铁橄榄石相，破坏蛇纹石的晶格结构，提高镍的活性，有利于镍的氯化和离析；而氯化剂所释放的氯成为铁迁移的媒介；冷却过程中物相没有发生明显变化。当生料中Fe3O4的加入量为原矿的10%(质量分数)时，精矿中镍的品位达到13.14%，回收率达到80.12%，比未加Fe3O4时的回收率提高了约10%。
关键字: 红土镍矿；氯化离析；物相转变；物相控制
chloridizing segregation of laterite ores
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:Under conditions of chlorinating agent dosage (CaCl2·2H2O) of 8% (vs mass of raw ore), reductant dosage of 6%(vs mass of raw ore) and heating rate of 5 ℃/min, the chloridizing segregation of nickel laterite ores from Philippines was carried out, and the phase transformation of chloridizing segregation of nickel laterite ores at temperatures up to1 000 ℃ and the phase reversibility with cooling were investigated by TG-DTA and XRD. The results show that the Fe-rich forsterite is formed with the ferrous oxide entering into the serpentine at 700 ℃. Therefore, the lattice structure of serpentine is failure, which is beneficial to chloridizing segregation, since the activity of Ni is enhanced, and the chlorine that is released from chlorinating agent acts as the medium of the transfer of iron. The phase is not changed obviously in the cooling process. When Fe3O4 adding in the raw materials is 10% (mass fraction), the grade in the concentrate of Ni reaches 13.14%, and the recovery achieves 80.12%, which increases by 10% compared with that without adding Fe3O4.
Key words: nickel laterite ores; chloridizing segregation; phase transformation; phase control
