阅读说明：本技术 一种基于菱锰矿浸出-净化的绿色冶炼方法 (Green smelting method based on leaching-purification of rhodochrosite ) 是由 宫清颗 李玉虎 马晓磊 刘强 冯金龙 王顺林 曹才放 陈小刚 于 2021-06-06 设计创作，主要内容包括：本发明属于锰冶金领域,具体公开了一种基于菱锰矿浸出-净化的绿色冶炼方法,该方法采用两段反向加料逆流浸出工艺,即一段浸出以菱锰矿料浆为底液,将阳极液、硫酸溶液、或酸性浸出液加入其中,控制终点pH≥4.5,即可获得低杂质的锰浸出液；二段以一段浸出渣为原料,将阳极液或硫酸溶液加入其中,控制终点pH≤1.5,从而彻底提取一段浸出渣中的锰,获得低锰含量的二段浸出渣和酸性浸出液,将酸性浸出液返回一段浸出使用,二段浸出渣经洗涤后送渣场堆存或作为矿山填充材料；通过这一浸出工艺,不仅可实现杂质的分离,还可充分利用锰资源,降低酸、碱耗量。本发明具有工艺简单、成本低、锰回收率高、辅料消耗低等优点,具有良好的产业化应用前景。(The invention belongs to the field of manganese metallurgy, and particularly discloses a green smelting method based on rhodochrosite leaching-purification, which adopts a two-stage reverse feeding countercurrent leaching process, namely, one-stage leaching takes rhodochrosite slurry as a base solution, anolyte, sulfuric acid solution or acid leachate is added into the base solution, and the pH value of a terminal point is controlled to be more than or equal to 4.5, so that manganese leachate with low impurities can be obtained; the second stage takes the first stage leaching slag as a raw material, an anolyte or a sulfuric acid solution is added into the first stage leaching slag, the pH value of the end point is controlled to be less than or equal to 1.5, so that manganese in the first stage leaching slag is completely extracted, the second stage leaching slag with low manganese content and an acidic leaching solution are obtained, the acidic leaching solution is returned to the first stage for leaching use, and the second stage leaching slag is washed and then sent to a slag yard for stockpiling or used as a mine filling material; through the leaching process, not only can the separation of impurities be realized, but also the manganese resource can be fully utilized, and the consumption of acid and alkali is reduced. The method has the advantages of simple process, low cost, high manganese recovery rate, low auxiliary material consumption and the like, and has good industrial application prospect.)

1. A green smelting method based on rhodochrosite leaching-purification is characterized by comprising the following steps:

the method comprises the following steps:

mixing rhodochrosite powder into water as a base solution, adding seed crystal accounting for 0.05-0.5% of the mass of the rhodochrosite powder, adding a section of leaching agent with the pH not higher than 1.5 and not lower than 1.0, and controlling the pH of a leaching end point to be not less than 4.5 so as to precipitate and remove iron, aluminum and silicon in leaching;

step two: carrying out solid-liquid separation on the solution so as to obtain a first-stage leaching solution and a first-stage leaching residue;

step three: taking the first-stage leaching slag in the second step as a raw material, adding seed crystals accounting for 0.05-0.5% of the weight of the rhodochrosite powder, and then adding a second-stage leaching agent into the seed crystals, wherein the pH value of a terminal point is controlled to be less than or equal to 1.5, so that manganese in the first-stage leaching slag is completely leached;

step four: carrying out solid-liquid separation on the solution so as to obtain second-stage leaching residue with low manganese content and acid leaching solution with high impurity content;

step five: purifying and electrolyzing the first-stage leachate to obtain a product.

2. The green smelting method based on rhodochrosite leaching-purification according to claim 1, wherein the particle size of the rhodochrosite powder is larger than 200 mesh.

3. The green smelting method based on rhodochrosite leaching-purification according to claim 1, wherein the seed crystal is white carbon black powder with the particle size of more than 400 meshes.

4. The green smelting method based on rhodochrosite leaching-purification according to claim 1, wherein the first-stage leaching agent and the second-stage leaching agent are both mixed liquor of sulfuric acid and anolyte.

5. The green smelting method based on rhodochrosite leaching-purification, according to claim 4, wherein the initial sulfuric acid concentration of the secondary leaching slag is 40-80 g/L.

6. The green smelting method based on rhodochrosite leaching-purification according to claim 5, wherein the concentrations of iron, aluminum and silicon in the primary leaching solution are respectively not more than 2mg/L, 50 mg/L and 30 mg/L.

7. The green smelting method based on rhodochrosite leaching-purification, according to claim 1, wherein the first leaching agent and the second leaching agent are added in an atomizing or spraying manner, and the feeding time is more than 40 min.

8. The green smelting method based on rhodochrosite leaching-purification according to claim 1, further comprising the following step after the fourth step: adding the leachate obtained in the fourth step into the first step to be used as a leaching agent.

Technical Field

The invention belongs to the field of manganese metallurgy, and particularly relates to a green smelting method based on leaching-purification of rhodochrosite.

Background

Manganese is an important metal element and is widely used in the fields of ferrous metals, nonferrous metals, aerospace, electronic technology, new energy materials, chemical industry, agriculture and the like. Because the manganese can effectively improve the strength of the steel, eliminate the influence of S, O on the hot brittleness of the steel, and improve the hot workability and the cold brittleness effect of the steel, about 90 percent of the manganese is used for the steel industry all over the world. In addition, as the new energy industry rapidly rises, the amount of manganese used in the field of new materials is rapidly increased, and it is expected that global manganese consumption will keep a vigorous demand in the future. Meanwhile, although the manganese resource in China is rich, the resource with less rich ore and more poor ore is natural, so that the manganese industry in China faces greater survival pressure. Therefore, by strengthening the smelting technology, the deep utilization of resources is realized, the competitiveness of the manganese smelting technology in China is improved, and the method has important significance for the sustainable development of the manganese industry in China.

At present, electrolytic manganese or manganese sulfate is produced by adopting a sulfuric acid leaching-neutralization impurity removal-vulcanization impurity removal-oxidation impurity removal process mainly, the process is simple in technology and mature in process, but the problems of long flow and low manganese recovery rate exist. In the conventional leaching process, manganese in the rhodochrosite is leached by using anolyte or sulfuric acid solution, the pH value of the leaching end point is controlled to be about 3 in order to avoid leaching a large amount of impurities, but the manganese leaching effect is limited, so that the manganese content in slag is about 6 percent. In addition, in the conventional leaching, although iron, aluminum and silicon impurities in a part of solution can be removed when the pH value is 3, the purification depth is still insufficient, so secondary impurity removal is needed; the secondary impurity removal usually takes ammonia water as a neutralizer, and the pH value of the leachate is adjusted to be more than 5, so that iron, aluminum and silicon are further removed. The secondary impurity removal can obtain leachate with higher quality, but needs to be added with medicament, and has higher cost. Therefore, the leaching and purification process of the existing rhodochrosite is long, the manganese loss is large, and the medicament consumption is large, so that the technical and economic indexes of the traditional manganese smelting process are not high, and the development of a green and efficient manganese smelting production technology is urgently needed in the industry.

Disclosure of Invention

The invention aims to provide a green extraction method of manganese sulfate leachate so as to improve the technical and economic indexes of a manganese smelting process.

In order to achieve the aim, the invention provides a green smelting method based on rhodochrosite leaching-purification, which comprises the following steps:

the method comprises the following steps:

mixing rhodochrosite powder into water as a base solution, adding seed crystal accounting for 0.05-0.5% of the mass of the rhodochrosite powder, adding a section of leaching agent with the pH not higher than 1.5 and not lower than 1.0, and controlling the pH of a leaching end point to be not less than 4.5 so as to precipitate and remove iron, aluminum and silicon in leaching;

step two: carrying out solid-liquid separation on the solution so as to obtain a first-stage leaching solution and a first-stage leaching residue;

step three: taking the first-stage leaching slag in the second step as a raw material, adding seed crystals accounting for 0.05-0.5% of the weight of the rhodochrosite powder, and then adding a second-stage leaching agent into the seed crystals, wherein the pH value of a terminal point is controlled to be less than or equal to 1.5, so that manganese in the first-stage leaching slag is completely leached;

step four: carrying out solid-liquid separation on the solution so as to obtain second-stage leaching residue with low manganese content and acid leaching solution with high impurity content;

step five: purifying and electrolyzing the first-stage leachate to obtain a product.

The principle of the scheme is as follows:

through a large number of experiments, we find that the solubility of a manganese-containing phase (manganese carbonate) in rhodochrosite and impurity phases such as iron, aluminum and silicon is greatly different, and the impurity phases such as manganese, iron, aluminum and silicon can be separated by a dissolution control method, but because part of manganese exists in the forms of inclusion, wrapping and the like, the leaching of the part of manganese needs higher leaching acidity, and the leaching rate of iron, aluminum and silicon is increased by a high-acid leaching solution, so that the impurity content of the leaching solution is too high, and the purification difficulty is increased.

For this reason, it was found through further studies that the leaching of manganese from rhodochrosite is of a bipolarised character: i.e. 70-80% of the manganese is easily dissolved and the remaining manganese is poorly soluble, requiring a higher leaching acidity to complete the leaching. Therefore, a two-stage countercurrent circulating leaching method is designed to solve the contradiction between manganese leaching and impurity removal, namely, most of manganese in the rhodochrosite is used as a neutralizer to replace ammonia water by utilizing the characteristic that most of manganese is easy to dissolve, and the pH value is controlled to be more than or equal to 4.5 to remove the impurities in the acidic leaching solution, so that the one-stage leaching is completed; and then, performing secondary leaching on the primary leaching slag, adopting higher acidity, controlling the pH value of the leaching end point to ensure that manganese in the slag is completely leached, separating partial impurities by utilizing the solubility difference of the manganese and the impurities, thus completing the secondary leaching, and returning the secondary leaching liquid to the primary leaching for use.

Further, the particle size of the rhodochrosite powder is larger than 200 meshes. The reaction under the particle is more complete, and the effect is better.

Further, the seed crystal is white carbon black powder with the granularity of more than 400 meshes. When iron, aluminum and silicon in the acid pickling leaching solution are neutralized, an amorphous colloidal substance is mainly formed, the granularity is fine, the filtering performance is extremely poor, the white carbon black is added to serve as a crystal seed, the granularity of particles of impurity precipitates can be effectively increased, and favorable conditions are provided for subsequent liquid-solid separation.

Further, the first-stage leaching agent and the second-stage leaching agent are mixed liquid of sulfuric acid and anolyte.

Further, the initial sulfuric acid concentration of the second-stage leaching residue is 40-80 g/L.

Further, the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively not more than 2mg/L, 50 mg/L and 30 mg/L.

Further, the first-stage leaching agent and the second-stage leaching agent are added in an atomization or spraying mode, and the feeding time is more than 40 min. When reverse feeding is adopted, the leaching agent is added in an atomization or spraying mode, so that the separation effect of impurities and manganese can be effectively improved, the filterability of leached slag is improved, and the operation efficiency is improved. This is probably because reverse feeding effectively avoids the problem of local over-concentration of the leaching agent, significantly improving the selectivity of manganese and impurity separation.

Further, the method also comprises the following steps after the step four: adding the leachate obtained in the fourth step into the first step to be used as a leaching agent. The recycling, raw materials are saved, and the economic benefit is high.

In general, the invention firstly utilizes the difference of the dissolubility of a manganese-containing phase and an impurity phase in the rhodochrosite to complete the deep leaching of manganese in the rhodochrosite and the effective separation of silicon, iron and aluminum in a manganese leaching solution by a two-stage leaching process. Meanwhile, the separation characteristics of iron, aluminum, silicon and manganese are enhanced through the change of the feeding mode, the growth of precipitated particles is promoted through the introduction of white carbon black, and colloidal substances of small particles are adsorbed and trapped, so that the filtering performance of slag is improved, and the operation efficiency is improved. Through the work, under the condition that no extra medicament is added, the leaching characteristic of the chabazite manganese ore powder is utilized, so that the deep extraction of manganese can be completed, the high-efficiency removal of impurities such as iron, aluminum, silicon and the like in the leaching solution can be completed, and the green smelting of manganese is realized.

Compared with the prior art, the invention has the following advantages:

(1) the method has the advantages of simple process, mature process, no special equipment requirement and easy industrialization.

(2) The invention has the advantages of no extra medicament requirement, high acid utilization, low raw material consumption and low cost.

(3) The method has the advantages of high impurity removal depth, high manganese leaching rate, high resource utilization rate and good technical and economic indexes.

(4) The invention is environment-friendly, has no waste gas and waste water, and can further reduce the leaching residue, thereby having high ecological benefit.

(5) The leaching process of the invention only needs self reaction heat without additional heating, thus saving energy.

Drawings

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

Detailed Description

Example 1:

first-stage leaching: 1.05t of manganese chabazite ore powder (Mn:27.69%, Fe:1.32%, Al:1.87%, SiO2: 10.76%), 3.5 kg of white carbon black (-500 meshes) and 1.5m of 3 water are added into a reaction kettle in sequence, then stirring is started, acid leachate with pH of 6.1m3 of 1.1 is added into the reaction kettle, the feeding speed is 5m3/h, and the end-point pH is controlled to be 5.1. And after the addition is finished, continuously stirring and reacting for 60 min, and then filtering to obtain a first-stage leaching solution and a first-stage leaching residue. And (3) sampling and detecting the first-stage leaching solution, and measuring that the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively 1.1, 36.6 and 22.7mg/L, and the content of Mn in the first-stage leaching slag is 15.77%.

Secondary leaching: 3.25 t of first-stage leaching residue (H2O: 38%) and 1.5kg of white carbon black (-500 meshes) are added into a reaction kettle in sequence to be used as seed crystals, then stirring is started, mixed liquor of anolyte and sulfuric acid solution with 6.5 m3 sulfuric acid acidity of 70g/L is added into the reaction kettle in a spraying mode, the feeding speed of a leaching agent is 4.8 m3/H, and the end point pH is 1.4. And after the addition is finished, continuously stirring and reacting for 80 min, and then filtering to obtain a second-stage leaching solution and a second-stage leaching residue. And (3) carrying out sampling detection after washing and drying the second-stage leaching slag, measuring that the total manganese content in the slag is 0.78%, wherein the concentrations of manganese, iron, aluminum and silicon in the second-stage leaching solution are 40.46g/L, 845mg/L, 1486mg/L and 344mg/L respectively, and returning to the first-stage leaching for use as a leaching agent.

Example 2:

first-stage leaching: 0.96t of manganese chabazite ore powder (Mn:27.69%, Fe:1.32%, Al:1.87%, SiO2: 10.76%), 1.8 kg of white carbon black (-800 meshes) and 1.2m of 3 water are added into a reaction kettle in sequence, then stirring is started, acid leachate with pH of 7.2m3 of 1.3 is added into the reaction kettle, the feeding speed is 8m 3/h, and the end-point pH is controlled to be 4.8. And after the addition is finished, continuously stirring and reacting for 45 min, and then filtering to obtain a first-stage leaching solution and a first-stage leaching residue. And (3) sampling and detecting the first-stage leaching solution, and measuring that the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively 1.1 mg/L, 41.4 mg/L and 25.4mg/L, and the content of Mn in the first-stage leaching slag is 13.88%.

Secondary leaching: 2.86 t of first-stage leaching residue (H2O: 38%) and 0.9kg of white carbon black (-800 meshes) are added into a reaction kettle in sequence to serve as seed crystals, then stirring is started, mixed liquor of anolyte and sulfuric acid solution with acidity of 75g/L of 6.1m3 is added into the reaction kettle in a spraying mode, the feeding speed of a leaching agent is 6.5 m3/H, and the end point pH is 1.2. And after the addition is finished, continuously stirring and reacting for 70 min, and then filtering to obtain a second-stage leaching solution and second-stage leaching residues. And (3) carrying out sampling detection after washing and drying the second-stage leaching slag, measuring that the total manganese content in the slag is 0.52%, the concentrations of manganese, iron, aluminum and silicon in the second-stage leaching solution are 41.07g/L, 922mg/L, 1507mg/L and 358mg/L respectively, and returning to the first-stage leaching for use as a leaching agent.

Example 3:

first-stage leaching: 1.15t of manganese chabazite ore powder (Mn:27.69%, Fe:1.32%, Al:1.87%, SiO2: 10.76%), 4.2 kg of white carbon black (-500 meshes) and 1.8m of 3 water are added into a reaction kettle in sequence, then stirring is started, an acid leaching solution with the pH of 5.5m3 of 1.3 is added into the reaction kettle, the feeding speed is 5m3/h, and the end-point pH is controlled to be 5.5. And after the addition is finished, continuously stirring and reacting for 75 min, and then filtering to obtain a first-stage leaching solution and a first-stage leaching residue. And (3) sampling and detecting the first-stage leaching solution, and measuring that the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively 0.2, 7.6 and 3.2mg/L, and the content of Mn in the first-stage leaching slag is 18.21%.

Secondary leaching: 3.04 t of first-stage leaching residue (H2O: 39%) and 2.4kg of white carbon black (-800 meshes) are added into a reaction kettle in sequence to serve as seed crystals, then stirring is started, mixed liquor of anolyte and sulfuric acid solution with the sulfuric acid acidity of 8.1 m3 of 60g/L is added into the reaction kettle in a spraying mode, the feeding speed of a leaching agent is 5.5m 3/H, and the end point pH is 1.3. And after the addition is finished, continuously stirring and reacting for 50 min, and then filtering to obtain a second-stage leaching solution and a second-stage leaching residue. And (3) carrying out sampling detection after washing and drying the second-stage leaching residue, measuring that the total manganese content in the residue is 0.56%, wherein the concentrations of manganese, iron, aluminum and silicon in the second-stage leaching solution are 39.14g/L, 766mg/L, 1121mg/L and 318mg/L respectively, and returning to the first-stage leaching solution for use as a leaching agent.

Example 4:

first-stage leaching: 0.92t of manganese chabazite ore powder (31.22% of Mn, 0.85% of Fe, 1.04% of Al, 8.25% of SiO 2), 4.8 kg of white carbon black (-600 meshes) and 1.6m of 3 water are sequentially added into a reaction kettle, then stirring is started, an acid leaching solution with the pH value of 5.8m3 of 1.3 is added into the reaction kettle, the feeding speed is 5m3/h, and the end-point pH value is controlled to be 4.6. And after the addition is finished, continuously stirring and reacting for 50 min, and then filtering to obtain a first-stage leaching solution and a first-stage leaching residue. And (3) sampling and detecting the first-stage leaching solution, and measuring that the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively 1.8, 47.8 and 27.8mg/L, and the content of Mn in the first-stage leaching slag is 13.14%.

Secondary leaching: 3.18 t of first-stage leaching residue (H2O: 44%) and 1.1kg of white carbon black (-800 meshes) are added into a reaction kettle in sequence to serve as seed crystals, then stirring is started, mixed liquor of anolyte and sulfuric acid solution with 7.2m3 sulfuric acid degree of 65g/L is added into the reaction kettle in a spraying mode, the feeding speed of a leaching agent is 6.4m 3/H, and the end point pH is 1.4. And after the addition is finished, continuously stirring and reacting for 45 min, and then filtering to obtain a second-stage leaching solution and a second-stage leaching residue. And (3) carrying out sampling detection after washing and drying the second-stage leaching slag, measuring that the total manganese content in the slag is 0.84%, wherein the concentrations of manganese, iron, aluminum and silicon in the second-stage leaching slag are 42.31g/L, 775mg/L, 1276mg/L and 362mg/L respectively, and returning to the first-stage leaching for use as a leaching agent.

Example 5:

first-stage leaching: 1.05t of manganese chabazite ore powder (31.22% of Mn, 0.85% of Fe, 1.04% of Al, 8.25% of SiO 2), 2.7kg of white carbon black (-800 meshes) and 1.4m of 3 water are added into a reaction kettle in sequence, then stirring is started, acid leaching solution with the pH value of 5.5m3 of 1.4 is added into the reaction kettle, the feeding speed is 6m 3/h, and the end-point pH value is controlled to be 4.9. And after the addition is finished, continuously stirring and reacting for 70 min, and then filtering to obtain a first-stage leaching solution and a first-stage leaching residue. And (3) sampling and detecting the first-stage leaching solution, and measuring that the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively 1.7 mg/L, 41.1 mg/L and 25.7mg/L, and the content of Mn in the first-stage leaching slag is 15.82%.

Secondary leaching: 3.35 t of first-stage leaching residue (H2O: 36%) and 0.8kg of white carbon black (-800 meshes) are added into a reaction kettle in sequence to serve as seed crystals, then stirring is started, mixed liquor of anolyte and sulfuric acid solution with 6.4m3 sulfuric acid acidity of 70g/L is added into the reaction kettle in a spraying mode, the feeding speed of a leaching agent is 5.5m 3/H, and the end point pH is 1.2. And after the addition is finished, continuously stirring and reacting for 60 min, and then filtering to obtain a second-stage leaching solution and a second-stage leaching residue. And (3) carrying out sampling detection after washing and drying the second-stage leaching residue, measuring that the total manganese content in the residue is 0.54%, and the concentrations of manganese, iron, aluminum and silicon in the second-stage leaching solution are 40.64g/L, 885mg/L, 1674mg/L and 369mg/L respectively, and returning to the first-stage leaching solution for use as a leaching agent.

Example 6:

first-stage leaching: 1.22t of manganese chabazite ore powder (25.37% of Mn, 1.15% of Fe, 1.26% of Al, 11.83% of SiO 2), 3.6 kg of white carbon black (-800 meshes) and 1.6m of 3 water are added into a reaction kettle in sequence, then stirring is started, acid leaching solution with the pH of 6.4m3 of 1.2 is added into the reaction kettle, the feeding speed is 5m3/h, and the end-point pH is controlled to be 5.4. And after the addition is finished, continuously stirring and reacting for 60 min, and then filtering to obtain a first-stage leaching solution and a first-stage leaching residue. And (3) sampling and detecting the first-stage leaching solution, and measuring that the concentrations of iron, aluminum and silicon in the first-stage leaching solution are respectively 0.4, 7.6 and 11.2mg/L, and the content of Mn in the first-stage leaching slag is 19.72%.

Secondary leaching: 2.76 t of first-stage leaching residue (H2O: 40%) and 2.7kg of white carbon black (-600 meshes) are added into a reaction kettle in sequence to serve as seed crystals, then stirring is started, mixed liquor of anolyte and sulfuric acid solution with 5.8m3 sulfuric acid acidity of 75g/L is added into the reaction kettle in a spraying mode, the feeding speed of a leaching agent is 6.4m 3/H, and the end point pH is 1.1. And after the addition is finished, continuously stirring and reacting for 70 min, and then filtering to obtain a second-stage leaching solution and second-stage leaching residues. And (3) sampling and detecting after washing and drying the second-stage leached slag, measuring that the total manganese content in the slag is 0.44%, the concentrations of manganese, iron, aluminum and silicon in the second-stage leached liquid are 41.55g/L, 983mg/L, 1855mg/L and 387mg/L respectively, and returning to the first-stage leaching for use as a leaching agent.

Comparative example 1:

the comparative example is different from example 1 in that white carbon black is not added into the reaction kettle, and other data are completely the same. The Mn content in the first-stage leaching residue is 30.71 percent, and the Mn content in the second-stage leaching residue is 8.85 percent.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.