LEACHING TREATMENT METHOD OF NICKEL OXIDE ORE

To provide a method of obtaining efficiently and stably a high Ni leaching rate in a leaching process of performing sulfuric acid leaching under high temperature and high pressure to a raw material Ni oxide ore.SOLUTION: In a partitioned chamber 2a on the most upstream of an autoclave 1 partitioned an interior into three or more partitioned chambers 2a to 2g by partition walls 1a to 1f, an ore slurry prepared by adding water to a raw material of nickel oxide ore is charged to sequentially transfer the ore slurry toward the partitioned chamber 2g on the most down stream to perform leaching treatment with sulfuric acid while stirring under high temperature and high pressure in each of the partitioned chambers 2a to 2g to leach the nickel oxide ore, only to the most upstream partitioned chamber 2a and the partitioned chamber adjacent thereto among the plurality of partitioned chambers 2a to 2g, the sulfuric acid is supplied.SELECTED DRAWING: Figure 2 【課題】 原料のＮｉ酸化鉱石に対して高温加圧下で硫酸浸出処理を行う浸出工程において、高いＮｉ浸出率を効率良く安定的に得る方法を提供する。【解決手段】 隔壁１ａ〜１ｆにより内部が３つ以上の区画室２ａ〜２ｇに区画されたオートクレーブ１の最上流の区画室２ａに原料のニッケル酸化鉱石に水を加えて調製した鉱石スラリーを装入し、最下流の区画室２ｇに向けて順次該鉱石スラリーを移送することで区画室２ａ〜２ｇの各々において高温高圧下で攪拌しながら硫酸により浸出処理を行うニッケル酸化鉱石の浸出処理方法であって、該複数の区画室２ａ〜２ｇのうち最上流の区画室２ａとこれに隣接する区画室２ｂのみに該硫酸を供給する。【選択図】 図２