(中南大學 冶金科學與工程學院，長沙 410083)
摘 要: 在氯化劑CaCl2·2H2O的加入量為原礦質(zhì)量的8%(以氯計)、還原劑焦炭加入量為原礦質(zhì)量的6%及升溫速率為5 ℃/min的條件下，對菲律賓紅土鎳礦進行氯化離析；采用TG-DTA和XRD研究菲律賓紅土鎳礦氯化離析升溫至1 000 ℃及冷卻過程中的物相轉(zhuǎn)變。結(jié)果表明：紅土鎳礦中的氧化亞鐵在700 ℃開始進入蛇紋石中，形成富鐵橄欖石相，破壞蛇紋石的晶格結(jié)構(gòu)，提高鎳的活性，有利于鎳的氯化和離析；而氯化劑所釋放的氯成為鐵遷移的媒介；冷卻過程中物相沒有發(fā)生明顯變化。當生料中Fe3O4的加入量為原礦的10%(質(zhì)量分數(shù))時，精礦中鎳的品位達到13.14%，回收率達到80.12%，比未加Fe3O4時的回收率提高了約10%。
關(guān)鍵字: 紅土鎳礦；氯化離析；物相轉(zhuǎn)變；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
