本文介绍了低品位红土镍矿高压浸出(HPAL)工艺中镍钴沉淀富集技术的由来及发展情况,详细阐述了目前应用过程中存在的问题,同时着重介绍了中国恩菲独创的碱基活化控制技术(AACP).该核心技术包括3 个关键环节,即氢氧化钠原位碱基转化、前置晶种重整与模板诱导生长、收敛式系统调控,其规避了国外企业在硫化氢、氧化镁沉淀技术中通过专利等手段设置的技术壁垒,技术工艺巧妙,装备简单通用,与高压浸出系统兼容性强,氢氧化镍钴(MHP)产品质量优异且稳定.此外,中国恩菲针对HPAL存在的问题,开发了高压酸浸工艺装备工程系统(ENFIHPAL),缩短了项目实施周期,且对装备系统整体进行基本选型设计、优化以及问题判别,可最大程度保证装备系统在复杂运行条件下的稳定性和作业率.AACP技术继巴布亚新几内亚的瑞木镍钴项目成功应用后,于印尼的力勤、华越等项目亦获得了显著的应用效果,生产的MHP产品已成为目前EV动力电池产业链原料供应端质量最好的中间产品.HPAL-AACP工艺路线有望成为低品位红土镍矿高效利用的首选之路.
In this paper,the origin and development of nickel-cobalt precipitation and enrichment technology in high-pressure acid leaching(HPAL)process for low-grade laterite nickel ore are introduced.The problems existing in the current application process are described in detail.At the same time,the alkali activation controlling technology(AACP)invented by ENFI is emphatically introduced.The technology includes three core technologies,in-situ base conversion of sodium hydroxide,pre-seeding reforming and template-induced growth,and convergent system regulation.It avoids the technical barriers set by foreign companies through patents in hydrogen sulfide and magnesium oxide precipitation technologies.The technical process is ingenious,the equipment is simple and universal,and the compatibility with the high-pressure leaching system is strong.The quality of nickel-cobalt hydroxide(MHP)products is excellent and stable.Moreover,ENFI has developed a high-pressure acid leaching process equipment engineering system(ENFIHPAL)for the problems existing in HPAL,which shortens the project implementation cycle,and carries out basic selection design,optimization and problem discrimination for the whole equipment system,which can ensure the stability and operation rate of the equipment system under complex operating conditions.After the successful application of AACP technology in Ruimu nickel-cobalt project in Papua New Guinea,it has also achieved remarkable application results in Liqin project,Huayueproject and other projects in Indonesia.The MHP products have become the best quality intermediate products at the raw material supply of the EV power battery industry.The HPAL-AACP process route is expected to be the first choice for the efficient utilization of low-grade laterite nickel ore.