In the high-pressure acid leaching method applied for the recovery of Ni and Co from lateritic ores, acid addition is usually fed from the first compartment inlet of the autoclave. This paper describes how the recovery of Ni and Co and the scale formation process in the autoclave are affected by the staged-addition of acid at different dosages. In addition to a single dose, sulfuric acid was fed to the leaching process performed in a novel designed autoclave experimental set-up at ascending, descending, and equal amounts in two and three stages. The results showed that the staged-addition of acid into the autoclave both increased the Ni and Co metal recovery and almost eliminated the formation of scales. It was found that when the acid was fed to the autoclave in three stages, Ni and Co recoveries increased from 85% to 87% and from 86% to 89%, respectively, compared to single-dose and two-stage acid addition tests. The improvement in recovery also increased the selectivity of Ni and Co relative to impurities. Besides, it was determined that the scale formation in the autoclave was 11 times less in two-stage acid addition and 31 times less in three-stage acid addition compared to single-dose feeding.

在用于从红土矿石中回收镍和钴的高压酸浸法中，酸添加通常从高压釜的第一隔室入口进料。本文介绍了不同剂量的分阶段添加酸如何影响 Ni 和 Co 的回收率以及高压釜中的结垢过程。除了单剂量外，硫酸还被加入到浸出过程中，该过程在一个新设计的高压釜实验装置中以上升、下降和等量分两个和三个阶段进行。结果表明，向高压釜中分阶段加入酸既提高了镍和钴金属的回收率，又几乎消除了水垢的形成。发现当酸分三个阶段加入高压釜时，Ni 和 Co 的回收率从 85% 提高到 87%，从 86% 提高到 89%，分别与单剂量和两阶段酸添加试验进行比较。回收率的提高也提高了 Ni 和 Co 相对于杂质的选择性。此外，与单次加酸相比，确定高压釜中的水垢形成在两段加酸中减少了 11 倍，在三段加酸中减少了 31 倍。