| 摘要 |
A low-pressure leaching process that extracts nickel and other valuable constituents from both limonite and saprolite ore. It takes advantage of the mineralogy of the ores to induce in-process iron hydrolysis that regenerates acid, thereby minimizing overall acid requirement. Leaching with sulfuric acid is performed in two stages, which is composed of an atmospheric tank leaching stage and a low-pressure autoclave leaching stage. The high iron, low magnesium size fraction of the ore is leached in the atmospheric tank leaching stage, while the high magnesium, low iron size fraction of the ore is leached in the autoclave leaching stage. Depending on the chosen downstream treatment technology, the pregnant leach solution can undergo a more extensive purification stages such as ion exchange and solvent extraction to produce the purer nickel hydroxide product, or it can proceed directly to mixed hydroxide product precipitation stages. |
