阅读说明：本技术 一种提高红土矿浸出液镍离子浓度的浸出方法 (Leaching method for improving nickel ion concentration of laterite leaching solution ) 是由 贺来荣 王贤来 欧晓健 沙滨 宗红星 张鹏 陈小林 魏建周 王多江 姚菲 王少华 于 2020-12-09 设计创作，主要内容包括：本发明提供了一种提高红土矿浸出液镍离子浓度的浸出方法,包括以下步骤：(1)将红土矿原料加水浆化,控制红土矿浆料液固比为3～4:1；(2)按照酸矿比为0.15～0.20:1将浓硫酸加入红土矿浆料中进行高温浸出,完成浸出后液固分离,得到浸出液和浸出渣；(3)将70～80%的浸出液返回步骤(1)中,并补入新水制备红土矿浆料,剩余20～30%的浸出液作为最终浸出液进入后续净化工序,浸出液如此往复循环。本发明相比现有高压酸浸工艺可将最终浸出液镍离子的浓度从3～5g/L,提高至8～10g/L,镍杂比从2～3:1提高至5～6:1,浸出液体积量缩小2～3倍。由于浸出液镍离子浓度高,镍杂比低,浸出液体积量小,为后续溶液净化工序创造了便利的条件,实现红土矿高效环保的浸出的目的。(The invention provides a leaching method for improving the nickel ion concentration of laterite leaching solution, which comprises the following steps: (1) adding water into a laterite raw material for slurrying, and controlling the solid-to-liquid ratio of laterite slurry to be 3-4: 1; (2) adding concentrated sulfuric acid into the laterite slurry according to the acid-ore ratio of 0.15-0.20: 1 for high-temperature leaching, and performing liquid-solid separation after leaching to obtain a leaching solution and leaching residues; (3) and (3) returning 70-80% of the leachate to the step (1), supplementing new water to prepare laterite slurry, taking the residual 20-30% of the leachate as a final leachate, and performing subsequent purification procedures, wherein the leachate is circulated repeatedly. Compared with the existing high-pressure acid leaching process, the concentration of nickel ions in the final leaching solution can be increased from 3-5 g/L to 8-10 g/L, the nickel-impurity ratio is increased from 2-3: 1 to 5-6: 1, and the volume of the leaching solution is reduced by 2-3 times. Because the nickel ion concentration of the leaching solution is high, the nickel-impurity ratio is low, and the volume of the leaching solution is small, convenient conditions are created for the subsequent solution purification process, and the purpose of leaching laterite efficiently and environmentally is achieved.)

1. A leaching method for improving the nickel ion concentration of laterite leaching solution comprises the following steps:

(1) adding water into a laterite raw material for slurrying, and controlling the solid-to-liquid ratio of laterite slurry to be 3-4: 1;

(2) adding concentrated sulfuric acid into the laterite slurry according to the acid-ore ratio of 0.15-0.20: 1 for high-temperature leaching, and performing liquid-solid separation after leaching to obtain a leaching solution and leaching residues;

(3) and (3) returning 70-80% of the leachate to the step (1), supplementing new water to prepare laterite slurry, taking the residual 20-30% of the leachate as a final leachate, and performing subsequent purification procedures, wherein the leachate is circulated repeatedly.

2. A method of leaching laterite ore with high ionic concentration according to claim 1, characterised by the steps of: in the step (2), the leaching temperature is 240-250 ℃, and the leaching time is 1-1.5 h.

3. A method of leaching laterite ore with high ionic concentration according to claim 1, characterised by the steps of: in the step (3), the new water is supplemented according to the water-ore ratio of 1-1.5: 1.

Technical Field

The invention belongs to the technical field of nonferrous metal hydrometallurgy, and particularly relates to a leaching method for improving the concentration of nickel ions in laterite leaching solution.

Background

In recent years, laterite smelting technology develops faster, and different smelting processes are adopted according to different raw ore characteristics. The laterite can be divided into laterite of a limonite layer, laterite of a transition layer and laterite of a saprolite layer from top to bottom in sequence. The limonite type laterite ore positioned at the upper part of the ore deposit is characterized in that the contents of nickel, silicon and magnesium are low, the contents of iron and cobalt are high, and the ore is suitable to be processed by a high-pressure acid leaching process (a wet smelting process). Laterite in the saprolite layer at the lower part of the deposit is characterized by high contents of nickel, silicon and magnesium and low contents of iron and cobalt, and the laterite is preferably processed by the RKEF process (pyrometallurgical process). And the ore in the intermediate transition layer is used as a material to be matched with limonite type laterite ore or saprolite layer laterite ore for processing. At present, the pyrometallurgical technology is mature, and although the hydrometallurgical technology is industrialized, the disadvantages of low nickel ion concentration, low nickel-impurity ratio, large volume of leachate and the like exist, so that the development of the technology is severely restricted.

Disclosure of Invention

The invention aims to solve the technical problems in the prior art, and provides an efficient and environment-friendly leaching method for improving the nickel ion concentration of laterite leaching solution, which can effectively improve the nickel ion concentration of the leaching solution, increase the nickel-impurity ratio (the nickel ion concentration: the sum of iron and aluminum ion concentrations) and reduce the volume of the leaching solution.

In order to achieve the purpose, the invention adopts the following technical scheme:

a leaching method for improving the nickel ion concentration of laterite leaching solution comprises the following steps:

(1) adding water into a laterite raw material for slurrying, and controlling the solid-to-liquid ratio of laterite slurry to be 3-4: 1;

(2) adding concentrated sulfuric acid into the laterite slurry according to the acid-ore ratio of 0.15-0.20: 1 for high-temperature leaching, and performing liquid-solid separation after leaching to obtain a leaching solution and leaching residues; leaching at 240-250 ℃ for 1-1.5 h;

(3) and (3) returning 70-80% of the leachate to the step (1), supplementing new water according to the water-to-ore ratio of 1-1.5: 1 to prepare laterite slurry, taking the residual 20-30% of the leachate as a final leachate, and performing subsequent purification procedures, wherein the leachate is circulated repeatedly.

Compared with the prior art, the invention has the following beneficial effects: according to the invention, part of the returned leachate is mixed with laterite raw materials, a certain amount of new water slurry is supplemented, and then high-temperature leaching is carried out, compared with the existing high-pressure acid leaching process, the concentration of nickel ions in the final leachate can be increased from 3-5 g/L to 8-10 g/L, the nickel-impurity ratio is increased from 2-3: 1 to 5-6: 1, and the volume amount of the leachate is reduced by 2-3 times. Because the nickel ion concentration of the leaching solution is high, the nickel-impurity ratio is low, and the volume of the leaching solution is small, convenient conditions are created for the subsequent solution purification process, and the purpose of leaching laterite efficiently and environmentally is achieved.

Drawings

FIG. 1 is a schematic process flow diagram of the present invention.

Detailed Description

The invention is further described with reference to the following figures and specific examples.

Example 1

The laterite ore feed composition is shown in table 1:

the leaching method of the laterite raw material comprises the following steps:

(1) adding water into the laterite raw material for slurrying, and controlling the solid-to-liquid ratio of the laterite slurry to be 3: 1;

(2) adding concentrated sulfuric acid into the laterite slurry according to the acid-ore ratio of 0.15:1 for high-temperature leaching, wherein the leaching temperature is 250 ℃, and the leaching time is 1.5 h. After leaching, carrying out liquid-solid separation to obtain a leaching solution and leaching residues;

(3) and (3) returning 70% of the leachate to the step (1), supplementing new water according to the water-to-ore ratio of 1:1 to prepare laterite slurry, taking the remaining 30% of the leachate as a final leachate, and performing subsequent purification procedures, wherein the leachate is circulated repeatedly.

Leaching results: the nickel ion concentration of the leaching solution is 8.13g/L, the nickel-impurity ratio is 5.19, and the final leaching solution amount output by 1kg of laterite raw material is 1.37L.

Example 2

The laterite feed composition is shown in table 2:

the leaching method of the laterite raw material comprises the following steps:

(1) adding water into the laterite raw material for slurrying, and controlling the solid-to-liquid ratio of the laterite slurry to be 4: 1;

(2) adding concentrated sulfuric acid into the laterite slurry according to the acid-ore ratio of 0.20:1 for high-temperature leaching, wherein the leaching temperature is 240 ℃, and the leaching time is 1 h. After leaching, carrying out liquid-solid separation to obtain a leaching solution and leaching residues;

(3) and (3) returning 80% of the leachate to the step (1), supplementing new water according to the water-mineral ratio of 1.5:1 to prepare laterite slurry, taking the residual 20% of leachate as a final leachate, and performing subsequent purification procedures, wherein the leachate is circulated repeatedly.

Leaching results: the nickel ion concentration of the leaching solution is 8.27g/L, the nickel-impurity ratio is 5.51, and the final leaching solution amount output by 1kg of laterite raw material is 1.25L.

Example 3

The laterite feed composition is shown in table 3:

the high ion concentration leaching method of the laterite raw material comprises the following steps:

(1) adding water into the laterite raw material for slurrying, and controlling the solid-to-liquid ratio of the laterite slurry to be 3: 1;

(2) adding concentrated sulfuric acid into the laterite slurry according to the acid-ore ratio of 0.20:1 for high-temperature leaching, wherein the leaching temperature is 250 ℃, and the leaching time is 1 h. After leaching, carrying out liquid-solid separation to obtain a leaching solution and leaching residues;

(3) and (3) returning 80% of the leachate to the step (1), supplementing new water according to the water-to-ore ratio of 1:1 to prepare laterite slurry, taking the residual 20% of leachate as a final leachate, and performing subsequent purification procedures, wherein the leachate is circulated repeatedly.

Leaching results: the nickel ion concentration of the leaching solution is 9.62g/L, the nickel-impurity ratio is 5.83, and the final leaching solution amount output by 1kg of laterite raw material is 1.22L.