阅读说明：本技术 一种高效利用铜锌矿的选冶联合工艺 (Dressing and smelting combined process for efficiently utilizing copper-zinc ore ) 是由 赵红波 张雁生 张伊升 李书生 孙欣 于 2019-10-17 设计创作，主要内容包括：本发明涉及一种高效利用铜锌矿的选冶联合工艺,在选矿阶段,铜锌混合矿原矿通过破碎、磨矿和分级等工艺达合适粒度后,利用混合浮选,得到回收率较高的铜锌混合精矿；然后,在铜锌分离阶段,将上述步骤所得铜锌混合精矿进行调浆、脱药处理,预备进行生物浸出或化学浸出。根据所使用的浸出方法,调控浸出体系的电位、pH值、矿浆浓度、温度、浸出药剂配比、浸矿微生物种类及浓度,最终实现铜锌混合精矿中锌的选择性溶出。得到铜精矿及含锌离子的浸出液；最后,经湿法或火法冶金工艺处理,最终得到金属铜和金属锌。本发明的工艺,流程简单、技术完善、综合回收率高、铜锌分离彻底、成本较低,有利于实现工业化应用。(The invention relates to a dressing-smelting combined process for efficiently utilizing copper-zinc ores, wherein in a dressing stage, copper-zinc mixed ore raw ores are subjected to crushing, ore grinding, grading and other processes to reach proper granularity, and then mixed flotation is utilized to obtain copper-zinc mixed concentrates with high recovery rate; and then, in the copper-zinc separation stage, carrying out size mixing and reagent removal treatment on the copper-zinc bulk concentrate obtained in the step, and preparing for bioleaching or chemical leaching. According to the used leaching method, the potential, the pH value, the ore pulp concentration, the temperature, the leaching agent ratio, the species and the concentration of leaching microorganisms of the leaching system are regulated and controlled, and the selective leaching of zinc in the copper-zinc bulk concentrate is finally realized. Obtaining copper concentrate and leachate containing zinc ions; finally, the metal copper and the metal zinc are finally obtained through wet or fire metallurgy process treatment. The process has the advantages of simple flow, complete technology, high comprehensive recovery rate, thorough copper and zinc separation and lower cost, and is beneficial to realizing industrial application.)

1. A dressing and smelting combined process for efficiently utilizing copper-zinc ores comprises the following steps:

(1) crushing and screening the copper-zinc mixed ore to obtain fine ore with qualified granularity;

(2) Grinding and grading the fine ore to obtain ore pulp meeting the requirement of flotation granularity;

(3) carrying out copper-zinc mixed flotation on the ore pulp to obtain copper-zinc mixed concentrate;

(4) Leaching zinc from the copper-zinc mixed ore concentrate by adopting biological or chemical selectivity, and performing solid-liquid separation to obtain low-zinc high-grade copper concentrate and a zinc-containing leachate;

(5) Purifying, concentrating, cooling and crystallizing the zinc-containing leachate to obtain a zinc sulfate product; or purifying, extracting and electrodepositing the zinc-containing leachate to obtain a zinc plate;

(6) Returning residual liquid generated by the crystallization and the extraction in the step (5) to the step (4) for mixed pulping after adding a chemical oxidant or oxidizing by microorganisms;

(7) smelting, converting and oxidizing the high-grade copper concentrate to obtain metal copper; or roasting, leaching and electrodepositing the high-grade copper concentrate to obtain the metal copper.

2. The process according to claim 1, wherein in the step (1), the copper-zinc mixed ore mainly contains copper sulfide minerals and zinc sulfide minerals, the copper grade is more than or equal to 0.4%, and the zinc grade is more than or equal to 2%.

3. The process according to claim 1, wherein the qualified fine ore has a grain size of 13mm or less in step (1).

4. The process of claim 1, wherein in step (2), the feed size for flotation is-200 mesh ≥ 65%.

5. The process of claim 1, wherein in step (3), the flotation is copper-zinc bulk flotation.

6. The process of claim 1, wherein in the step (4), the copper-zinc mixed ore concentrate is subjected to size mixing and reagent removal treatment by using bioselective leaching to obtain mixed ore concentrate pulp; then adjusting the pH value of the ore pulp by using dilute sulfuric acid, adding ore leaching bacteria, and stirring and leaching.

7. The process of claim 6 wherein the concentration of the mixed concentrate pulp is 1-30%, the pulp pH is adjusted to 1.0-2.5 with dilute sulfuric acid, the total iron concentration is controlled to 0.1-1.0mol/L, and the bacteria concentration is controlled to not less than 10⁷Stirring at 15-200rpm, controlling the temperature of the leaching system at 30-80 deg.C, controlling the leaching potential at 600-790mV relative to the saturated silver/silver chloride electrode, and leaching for 1-5 days.

8. The process according to claim 6, wherein the leaching bacteria is one or more of Acidithiobacillus ferrooxidans, Leptospira ferrooxidans and Leptospira ferrooxidans.

9. the process of claim 1, wherein in the step (4), chemoselective leaching is selected, and the copper-zinc mixed ore concentrate is subjected to size mixing and reagent removal treatment to obtain mixed ore concentrate pulp; then dilute sulphuric acid is used for adjusting the pH value of the ore pulp, an oxidant is added, and then stirring leaching is carried out.

10. The process of claim 9, the oxidant being Fe³⁺Oxygen and halogen element simple substance, nitrate, persulfate, permanganate, oxyacid of chlorine and salt thereof, and peroxide; the concentration of the mixed concentrate ore pulp is 1-30%, the pH of the ore pulp is adjusted to be 0.5-2.5, the leaching potential is controlled to be 810-1000mV relative to a saturated silver/silver chloride electrode, the stirring speed is 15-1000rpm, the temperature of a leaching system is controlled to be 30-100 ℃, and the leaching time is 1-48 hours.

Technical Field

The invention relates to efficient separation and extraction of metal copper and zinc in a copper-zinc mixed ore in the fields of mineral processing and wet metallurgy, in particular to a process for effectively separating copper minerals and zinc minerals in the copper-zinc mixed ore to obtain leachate containing zinc ions and copper concentrate, and finally obtaining metal zinc and metal copper.

Background

In the field of mineral processing and smelting, copper and zinc separation is a difficult problem which troubles the industry for a long time. In nature, copper and zinc are mainly present in the form of sulfides. Flotation is commonly used in the mineral processing field to separate sulphide ores from oxidised ores (most gangue minerals) based on differences in their hydrophilicity and hydrophobicity. However, non-ferrous metal minerals often exist as co-associated polymetallic complex sulfide deposits, wherein copper sulfide minerals are often co-associated with zinc sulfide minerals. During the flotation process, the activation of the copper ions in the pulp on the surface of the zinc sulfide mineral reduces the difference of the surface hydrophobicity of the copper sulfide mineral and the zinc sulfide mineral, so that the copper and the zinc are difficult to separate by using the flotation method. Thus, even up to 10% by mass of zinc is present in the copper concentrate obtained industrially. The residual zinc in the copper concentrate is separated in the form of soot during the pyrometallurgical copper smelting, the soot needs to be collected and treated, the process is complex, the cost is high, otherwise, the zinc resource waste is faced, and the price of the copper concentrate is reduced. Therefore, the development of an effective copper-zinc separation process has wide industrial application prospects.

In industrial production, the most common copper-zinc separation method is the preferential flotation method. The method is used for floating useful minerals one by one in an easy-to-first-difficult sequence according to the difference of floatability of the useful minerals. The method requires that the raw ore grade is high, the difference of the floatability of the copper ore and the zinc ore in the raw ore is large, but the method has poor effect on poor ores and the situation that the floatability of the zinc ore after copper ion activation is similar to that of the copper ore. In addition, the preferential flotation method requires longer flotation time, more flotation machines, higher cost in ore grinding sections, and higher production cost due to the consumption of a large amount of inhibitors and activators. Therefore, as high-grade mineral products are reduced in nature, the properties of the mineral are more complex, and the copper-zinc separation by a preferential flotation method is more and more limited.

In addition to the most common methods of preferential flotation, methods such as mixed flotation, partial preferential-mixed flotation, iso-flotation, and thermal flotation are also used industrially. The ultimate goal of these processes is to separate the copper and zinc ores by flotation. Among them, the bulk concentrates of copper and zinc obtained by bulk flotation, partial preferential bulk flotation and iso-floatable processes often require further grinding to fully dissociate copper ores and zinc ores, and require a large amount of inhibitors and activators, which undoubtedly increases the cost. The heating flotation is to inhibit the floatability of zinc minerals by utilizing the temperature rise, and the consumption of a large amount of energy is an obvious defect.

At present, although the dressing and smelting combined process is also applied in industry, the processes comprise roasting desulfurization-acid leaching process, pressure leaching process, chlorination roasting water leaching and the like, and the aim is to simultaneously extract copper and zinc in the bulk concentrate obtained by flotation, the roasting, pressure and other methods consume a large amount of energy, and the obtained leachate still needs copper and zinc separation.

In order to solve the problem that the copper-zinc mixed ore is difficult to separate by using a flotation method, in order to reduce the zinc content in the copper concentrate and improve the quality of the copper concentrate, in order to utilize metal zinc in the copper-zinc mixed ore as resources and to realize copper-zinc separation by using an efficient method, a new process needs to be developed to realize the purposes.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a dressing-smelting combined process for efficiently utilizing copper-zinc ores, which skillfully realizes the separation of copper and zinc in copper-zinc mixed ores by utilizing a (biological) hydrometallurgy method. The method solves the industrial problem of copper-zinc separation, and the required copper-zinc bulk concentrate can be obtained by a simple equal-floatability (mixed flotation) method, thereby shortening the flotation flow and reducing the medicament use and energy consumption. The process has the advantages of simple flow, complete technology, high comprehensive recovery rate, thorough copper-zinc separation and low cost, and is favorable for realizing industrial application.

The invention adopts the following technical scheme for solving the technical problems: a dressing and smelting combined process for efficiently utilizing copper-zinc ores comprises the following steps:

(1) Crushing and screening the copper-zinc mixed ore to obtain fine ore with qualified granularity;

(2) Grinding and grading the fine ore to obtain ore pulp meeting the requirement of flotation granularity;

(3) Carrying out copper-zinc mixed flotation on the ore pulp to obtain copper-zinc mixed concentrate;

(4) Leaching zinc from the copper-zinc mixed ore concentrate by adopting biological or chemical selectivity, and performing solid-liquid separation to obtain low-zinc high-grade copper concentrate and a zinc-containing leachate;

(5) Purifying, concentrating, cooling and crystallizing the zinc-containing leachate to obtain a zinc sulfate product; or purifying, extracting and electrodepositing the zinc-containing leachate to obtain a zinc plate;

(6) Returning residual liquid generated by the crystallization and the extraction in the step (5) to the step (4) for mixed pulping after adding a chemical oxidant or oxidizing by microorganisms;

(7) Smelting, converting and oxidizing the high-grade copper concentrate to obtain metal copper; or roasting, leaching and electrodepositing the high-grade copper concentrate to obtain the metal copper.

Preferably, in the step (1), the copper-zinc mixed ore mainly contains copper sulfide minerals and zinc sulfide minerals, the copper grade is more than or equal to 0.4%, and the zinc grade is more than or equal to 2%.

Preferably, in the step (1), the qualified fine ore has a grain size of 13mm or less.

Preferably, in the step (2), the feeding granularity conforming to flotation is-200 meshes or more and 65%.

Preferably, in the step (3), the flotation is copper-zinc mixed flotation.

preferably, in the step (4), the biological selective leaching is selected, and the copper-zinc mixed ore concentrate is subjected to size mixing and reagent removal treatment to obtain mixed ore concentrate pulp; then adjusting the pH value of the ore pulp by using dilute sulfuric acid, adding ore leaching bacteria, and stirring and leaching.

Preferably, the concentration of the ore pulp of the bulk concentrate is 1-30%, the pH of the ore pulp is adjusted to 1.0-2.5 by using dilute sulfuric acid, the total iron concentration is controlled to be 0.1-1.0mol/L, and the bacteria concentration is controlled to be not less than 10⁷Stirring at 15-200rpm, controlling the temperature of the leaching system at 30-80 deg.C, controlling the leaching potential at 600-790mV relative to the saturated silver/silver chloride electrode, and leaching for 1-5 days.

Preferably, the ore leaching bacteria are one or more of acidithiobacillus ferrooxidans, leptospirillum ferrooxidans and leptospirillum ferrophilis.

Preferably, in the step (4), chemoselective leaching is selected, and the copper-zinc mixed ore concentrate is subjected to size mixing and reagent removal treatment to obtain mixed ore concentrate pulp; then dilute sulphuric acid is used for adjusting the pH value of the ore pulp, an oxidant is added, and then stirring leaching is carried out.

As a further preference, the oxidant is Fe³⁺Oxygen and halogen element simple substance, nitrate, persulfate, permanganate, oxyacid of chlorine and salt thereof, and peroxide; the concentration of the mixed concentrate ore pulp is 1-30%, the pH of the ore pulp is adjusted to be 0.5-2.5, the leaching potential is controlled to be 810-1000mV relative to a saturated silver/silver chloride electrode, the stirring speed is 15-1000rpm, the temperature of a leaching system is controlled to be 30-100 ℃, and the leaching time is 1-48 hours.

Compared with the prior art, the invention has the following advantages: 1. the used dressing and smelting combined process has no strict requirement on the grade of raw ore and is beneficial to the treatment of lower-grade mineral resources; 2. the flotation-smelting combined process efficiently utilizing the copper-zinc ores utilizes the mixed flotation method, avoids the defects of long process and large reagent consumption of the current common copper-zinc separation flotation process, simplifies the flotation process and reduces the consumption of the flotation reagent; 3. the copper-zinc sulfide ore is subjected to mixed flotation, so that the use of an inhibitor is avoided, and the recovery rate of the copper-zinc sulfide ore can reach over 90 percent; 3. the copper-zinc bulk concentrate obtained in the process flow does not need high-temperature heating pretreatment and pressurization treatment in the subsequent copper-zinc separation stage, so that a large amount of energy is saved, and the cost is low; 4. the process flow of the invention utilizes a (biological) hydrometallurgy method, realizes the purpose of separating copper and zinc by selectively dissolving out zinc, has no strict requirements on the grade and quality of the copper-zinc bulk concentrate obtained by flotation, and allows the copper-zinc bulk concentrate and other easily soluble minerals to be separated out together with the iron sulfide minerals and the like in the equal floatable (bulk flotation) stage; 5. the process has the advantages of simple flow, complete technology, high comprehensive recovery rate, thorough copper and zinc separation and lower cost, and is beneficial to realizing industrial application.

Drawings

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

Detailed Description

In order to make the technical means, the creation features, the achievement purposes and the effects of the invention easy to understand, the invention is further described below by combining the specific drawings and the 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.

Referring to fig. 1, the invention provides a dressing and smelting combined process for efficiently utilizing copper-zinc ores, which comprises the following steps: crushing and screening the copper-zinc mixed ore to obtain fine ore with qualified granularity; grinding and grading the fine ore to obtain ore pulp meeting the requirement of flotation granularity; carrying out copper-zinc mixed flotation on the ore pulp to obtain copper-zinc mixed concentrate, and mixing the copper-zinc mixed concentrate with water for size mixing; then leaching zinc by adopting biological or chemical selectivity, and performing solid-liquid separation to obtain low-zinc high-grade copper concentrate and zinc-containing leachate; purifying, concentrating, cooling and crystallizing the zinc-containing leachate to obtain a zinc sulfate product; or purifying, extracting and electrodepositing the zinc-containing leachate to obtain a zinc plate; the raffinate generated by the crystallization and the extraction is returned to the mixed pulping after being oxidized by adding a chemical oxidant or microorganisms; smelting, converting and oxidizing the high-grade copper concentrate to obtain metal copper; or roasting, leaching and electrodepositing the high-grade copper concentrate to obtain the metal copper.