阅读说明：本技术 一种p204萃取除杂过程中减少硫酸钙沉积的方法 (Method for reducing calcium sulfate deposition in P204 extraction impurity removal process ) 是由 许开华 蒋振康 胡意 谢贻斌 孟庆岩 王阳 于 2019-11-05 设计创作，主要内容包括：本发明属于湿法冶金技术领域,公开了一种P204萃取除杂过程中减少硫酸钙沉积的方法,对萃取后的P204负载有机相进行洗涤,所述洗涤包括一次洗涤和二次洗涤；在所述一次洗涤过程中和所述二次洗涤过程中均向所述P204负载有机相中加入水和盐酸；在一次洗涤过程中,水的流量为V-1,盐酸的流量为V-2；在二次洗涤过程中,水的流量为V-1’,盐酸的流量为V-2’；其中,V-1：V-2＝(8～12)：1,V-1’：V-2’＝(4～6):1。本发明的方法能够减少有机相中夹带的硫酸根,进而避免在洗涤段发生硫酸根与Ca～(2+)结合的问题,防止在洗涤过程中硫酸钙达到饱和浓度,从而减少硫酸钙沉淀析出。(The invention belongs to the technical field of hydrometallurgy, and discloses a method for reducing calcium sulfate deposition in a P204 extraction impurity removal process, wherein an extracted P204 loaded organic phase is washed, and the washing comprises primary washing and secondary washing; adding water and hydrochloric acid to the P204 loaded organic phase both during the primary washing and during the secondary washing; in one washing process, the flow rate of water is V 1 The flow rate of hydrochloric acid is V 2 (ii) a In the secondary washing process, the flow rate of water is V 1 ', the flow rate of hydrochloric acid is V 2 '; wherein, V 1 ：V 2 ＝(8～12)：1，V 1 ’：V 2 ' (4-6) and (1). The method can reduce sulfate radicals carried in the organic phase, thereby avoiding the generation of sulfate radicals and Ca in the washing section 2+ The problem of binding prevents calcium sulfate from reaching saturation concentration in the washing process, thereby reducing precipitation of calcium sulfate.)

1. A method for reducing calcium sulfate deposition in the process of P204 extraction and impurity removal is used for washing an extracted P204 loaded organic phase, and is characterized in that the washing comprises primary washing and secondary washing; adding water and hydrochloric acid to the P204 loaded organic phase both during the primary washing and during the secondary washing;

in the one-time washing process, the flow rate of the water is V₁The flow rate of the hydrochloric acid is V₂；

In the secondary washing process, the flow rate of the water is V₁', the flow rate of the hydrochloric acid is V₂’；

Wherein, V₁：V₂＝(8～12)：1，V₁’：V₂’＝(4～6):1。

2. The method for reducing calcium sulfate deposition during P204 extraction and impurity removal of claim 1, wherein V is₁And said V₂Has a relationship of V₁：V₂＝10:1。

3. The method for reducing calcium sulfate deposition during P204 extraction and impurity removal of claim 1, wherein V is₁' with said V₂' the relationship is V₁’：V₂’＝5:1。

4. The method for reducing the deposition of calcium sulfate in the P204 extraction and impurity removal process as claimed in any one of claims 1 to 3, wherein the concentration of the hydrochloric acid is 4mol/L to 6 mol/L.

5. A method for reducing calcium sulfate deposition in the process of P204 extraction impurity removal according to any one of claims 1-3, wherein the primary washing and the secondary washing are respectively carried out on the P204 loaded organic phase in the mixing-clarifying tank in sequence; and respectively conveying the washing liquid after twice washing into a washing liquid transfer tank.

6. The method for reducing calcium sulfate deposition in the P204 extraction impurity removal process according to claim 5, wherein the mixing time of the P204 loaded organic phase with water and hydrochloric acid in the primary washing process and the secondary washing process is 4-6 min.

Technical Field

The invention belongs to the technical field of hydrometallurgy, and particularly relates to a method for reducing calcium sulfate deposition in a P204 extraction impurity removal process.

Background

With the rapid development of electric vehicles, the research and production of ternary battery materials are also improved dramatically, the demand of high-purity nickel-cobalt metal is greatly increased, and the extraction and purification technology of cobalt and nickel is vigorously developed to meet the demand of ternary battery materials.

The existing process flow for purifying and enriching cobalt and nickel from a sulfuric acid solution rich in cobalt and nickel comprises the following steps: iron is removed by goethite method, and then P204 is used for extraction and impurity removal, back extraction and the like. In the process of removing impurities by P204 extraction, the extracted P204 organic phase needs to be washed. F in waste water^-The control is more strict, and the saturated Ca can not be removed by NaF before the P204 extraction impurity removal²⁺Then more Ca²⁺Ions will be introduced into the extraction process into the P204 organic phase. At the washing stage in the P204 extraction impurity removal process, Ca which is backwashed²⁺With SO₄ ^2-In combination, the calcium sulfate is deposited at the bottom of the extraction tank in a calcium sulfate precipitation mode, and as time goes on, calcium sulfate crystals are accumulated more, thicker and harder, so that the stirring paddle, the weir mouth, the pipe orifice and the clarification chamber of the extraction tank are blocked by the calcium sulfate crystals, a large amount of manpower is consumed for cleaning and shoveling, and the extraction efficiency is influenced.

Disclosure of Invention

In view of the above, the invention provides a method for reducing calcium sulfate deposition in the process of P204 extraction and impurity removal, and the method can be used for reducing calcium sulfate depositionReduce the sulfate radical carried in the organic phase, thereby avoiding the generation of sulfate radical and Ca in the washing section²⁺The problem of binding prevents calcium sulfate from reaching saturation concentration in the washing process, thereby reducing precipitation of calcium sulfate.

A method for reducing calcium sulfate deposition in the process of P204 extraction and impurity removal is characterized in that an extracted P204 loaded organic phase is washed, wherein the washing comprises primary washing and secondary washing; adding water and hydrochloric acid to the P204 loaded organic phase both during the primary washing and during the secondary washing;

in the one-time washing process, the flow rate of the water is V₁The flow rate of the hydrochloric acid is V₂；

In the secondary washing process, the flow rate of the water is V₁', the flow rate of the hydrochloric acid is V₂’；

Wherein, V₁：V₂＝(8～12)：1，V₁’：V₂’＝(4～6):1。。

Preferably, said V₁And said V₂Has a relationship of V₁：V₂＝10:1。

Preferably, said V₁' with said V₂' the relationship is V₁’：V₂’＝5:1。

Preferably, the concentration of the hydrochloric acid is 4mol/L to 6 mol/L.

Preferably, characterized in that said primary washing and said secondary washing are carried out in sequence on the P204 loaded organic phase in said mixing-clarifying tank, respectively; and respectively conveying the washing liquid after twice washing into a washing liquid transfer tank.

Preferably, in the primary washing and the secondary washing, the mixing time of the P204 loaded organic phase, water and hydrochloric acid is 4-6 min.

Compared with the prior art, the invention adopting the scheme has the beneficial effects that:

the washing section in the traditional P204 extraction impurity removal process is divided into primary washing and secondary washing, and the primary washing and the secondary washing are controlledThe flow of water, the flow of hydrochloric acid and the flow ratio of water to hydrochloric acid in each washing process in the washing process realize the purpose of washing out sulfate ions carried in the P204 organic phase in one washing process, thereby avoiding the generation of sulfate radicals and Ca in the whole washing process²⁺The problem of binding prevents calcium sulfate from reaching saturation concentration in the washing process, thereby reducing precipitation of calcium sulfate.

Drawings

FIG. 1 is a flow chart of a P204 extraction and impurity removal process according to an embodiment of the present invention;

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The embodiment provides a method for reducing calcium sulfate deposition in a P204 extraction and impurity removal process, and the extracted P204 loaded organic phase is washed, as shown in fig. 1, where the washing includes primary washing and secondary washing; adding water and hydrochloric acid into the P204 loaded organic phase in the primary washing process and the secondary washing process;

in one washing process, the flow rate of water is V₁The flow rate of hydrochloric acid is V₂；

In the secondary washing process, the flow rate of water is V₁', the flow rate of hydrochloric acid is V₂’；

Wherein, V₁：V₂＝(8～12)：1，V₁’：V₂’＝(4～6):1。

In this embodiment, the washing section in the conventional P204 extraction and impurity removal process is divided into primary washing and secondary washing, and the purpose of washing out the sulfate ions carried in the P204 loaded organic phase in the primary washing process is achieved by controlling the flow rate of water, the flow rate of hydrochloric acid, and the flow rate ratio of water to hydrochloric acid in each washing process, thereby avoiding the occurrence of sulfate and Ca in the whole washing process²⁺Problems of bonding, preventingAnd the calcium sulfate reaches the saturated concentration in the washing process, so that the precipitation of the calcium sulfate is reduced.

In a specific embodiment, V₁And V₂Is preferably V₁：V₂＝10:1；

In a specific embodiment, V₁' and V₂' the relationship is preferably V₁’：V₂’＝5:1；

Therefore, sulfate ions carried in the P204 loaded organic phase after one-time washing can be ensured to be combined with the washed calcium ions, and calcium sulfate can be further prevented from reaching the saturated concentration in the washing process, so that the precipitation of calcium sulfate is reduced.

In the specific embodiment, the concentration of the hydrochloric acid is 4-6 mol/L, so that the preparation of the hydrochloric acid is convenient while the main content concentration of the product is ensured.

In this embodiment, the hydrochloric acid concentration may be 5 mol/L.

In a specific embodiment, the P204 loaded organic phase is subjected to a primary washing and said secondary washing in sequence in a mixing-clarifying tank, respectively; and respectively conveying the washing liquid after twice washing into a washing liquid transfer tank.

The water phase collected by the transfer tank can be used for other purposes, and the water phase contains hydrochloric acid, so that the pH value of the water phase is low, the water phase can return to a cobalt-nickel leaching system to be used as acid, and the purpose of saving water is achieved.

In the embodiment, a washing section in the mixing-clarifying box type extraction process is divided into a primary washing section and a secondary washing section, hydrochloric acid and pure water are added into the primary washing section and the secondary washing section in proportion, and after full mixing and clarification, liquid obtained after two times of washing is discharged into a liquid transferring tank after washing respectively.

In the specific embodiment, in the processes of primary washing and secondary washing, the mixing time of the P204 loaded organic phase with water and hydrochloric acid is 4-6 min, so that the P204 loaded organic phase is fully mixed with water and hydrochloric acid, and the time can be saved.

The process of the invention is illustrated below with reference to specific examples:

as shown in fig. 1, before the P204 extraction and impurity removal process, firstly, saponifying P204 with sodium hydroxide, and then extracting the leachate containing nickel sulfate or cobalt sulfate through a P204 line to obtain a P204 loaded organic phase (the impurities contained therein contain metal ions such as calcium ions, copper ions, manganese ions, zinc ions, and the like, and also inevitably carry sulfate ions);

secondly, washing the P204 loaded organic phase for one time, adding hydrochloric acid with the flow rate of 20L/h and pure water with the flow rate of 80L/h in the washing process for one time, and obtaining a washing liquid containing Ca after one-time washing²⁺0.5g/L、 SO₄ ^2-5g/L, pH 3.5;

then, the P204 loaded organic phase after the primary washing is washed for the second time, the hydrochloric acid flow rate is 100L/h and the pure water flow rate is 400L/h are added in the secondary washing process, and Ca contained in the secondary washing liquid is obtained after the secondary washing²⁺3g/L、SO₄ ^2-0.005g/L and pH 3.5;

and finally, carrying out back extraction on the P204 loaded organic phase subjected to the secondary washing.

As can be seen from this example, P204 is loaded with a large amount of SO in the organic phase during one wash₄ ^2-Is washed out, thereby causing SO in the secondary washing liquid in the secondary washing process₄ ^2-The concentration of the sodium sulfate is lower, so that the calcium sulfate is prevented from reaching the saturated concentration in the washing process, and the precipitation of the calcium sulfate is reduced.

In addition, in this embodiment, the water phases after the two times of washing are respectively conveyed into the washing liquid transfer tank, and the water phase in the washing liquid transfer tank is conveyed to the leaching system for recycling, so as to obtain the leaching solution of nickel sulfate or cobalt sulfate.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.