Method for efficiently separating iron and manganese components in ferromanganese ore

Abstract

The invention relates to a method for efficiently separating iron and manganese components in ferromanganese ore, which comprises the following steps of: mixing the ferromanganese ore with an intermediate product or a vanadium product in the vanadium industry to obtain a mixed material, and roasting the mixed material at high temperature to obtain roasted clinker; the obtained roasting clinker is leached and then filtered, and manganese-containing and vanadium-containing leaching liquid and iron-containing leaching residues are obtained; adding a vanadium precipitation additive into the obtained manganese-containing and vanadium-containing leachate, adjusting the pH value for precipitation, and filtering after vanadium precipitation to obtain an intermediate product or a vanadium product in the vanadium industry and manganese-containing supernate; and precipitating or drying and crystallizing the obtained manganese-containing supernate, and then filtering to obtain a manganese product and manganese extraction waste liquid. According to the method, ore phase reconstruction of the manganese mineral in the ferromanganese ore is achieved by means of the vanadium industry intermediate product or the vanadium product, the vanadium industry intermediate product or the vanadium product can be recycled in the process, efficient separation of iron and manganese in the ferromanganese ore is achieved, and efficient recycling of the vanadium industry intermediate product or the vanadium product is achieved.

Description

Technical Field

[0001] The present invention relates to a method for efficiently separating iron and manganese components in an iron-manganese ore, in particular to a method for efficiently separating iron and manganese components in an iron-manganese ore using an intermediate product or a vanadium product in the vanadium industry and recycling the intermediate product or the vanadium product in the vanadium industry, belonging to the technical field of iron-manganese ore resource utilization, vanadium chemical technology and resource recycling. Background Art

[0002] Manganese is a major and scarce strategic metal that maintains the national economy. Most of China's manganese ore is iron-manganese ore with a low Mn / Fe mass ratio (<3). The output can no longer meet the rapid development of the metallurgical industry, and the external dependence of manganese ore is as high as 90%. At present, the main separation processes of iron and manganese are mechanical separation, manganese-rich slag separation, reduction roasting magnetic separation and leaching separation. Although they have been industrialized, these processes still face inevitable problems.

[0003] Mechanical separation methods mainly include gravity separation, flotation, magnetic separation, etc. Since the physical and chemical properties of iron and manganese in the ore are similar, the ore characteristics do not change significantly during the separation process, resulting in a single mechanical separation technology that is difficult to effectively separate valuable minerals from gangue minerals.

[0004] The manganese-rich slag separation method is a relatively mature separation process. It uses the difference in solubility between manganese slag and molten iron to make manganese enter the slag phase to obtain manganese-rich slag, while iron remains in a liquid state, thus achieving the separation of iron and manganese. However, this method requires coke as a reducing agent and smelting at high temperatures, which has the characteristics of high energy consumption and high pollution.

[0005] The reduction roasting magnetic separation method refers to adding reducing solids or gases to roast the ore before magnetic separation, so that iron is enriched in the strong magnetic phase, while manganese remains in the weak magnetic phase, further expanding the magnetic difference between manganese and iron. However, the commonly used carbon thermal reduction equipment is the vertical furnace and rotary kiln, which has complex processes, difficult mass and heat transfer, and high production and maintenance costs.

[0006] Leaching separation methods include chemical leaching and biological leaching. In the leaching process, it is common for iron and manganese to be leached together, which makes it difficult to remove iron from manganese in the future, and the chemical waste and wastewater generated during the experiment also increase, causing great harm to the environment.

[0007] From the perspectives of cost, environmental protection, recovery efficiency, etc., the above iron and manganese separation processes all have shortcomings, so it is urgent to find a process that is more suitable for iron and manganese ore separation. Summary of the invention

[0008] 1. Technical issues to be resolved

[0009] In order to solve the above problems in the prior art, the present invention proposes a method for efficiently separating iron and manganese components in ferromanganese ore. The method utilizes vanadium element to directionally reconstruct and transform the insoluble manganese minerals in the ferromanganese ore into acid-soluble manganese vanadate, and regulates the physical phase of the iron minerals, and then leaches them out through acid solution to achieve efficient separation of the iron and manganese components and recycling of roasting media.

[0010] (II) Technical solution

[0011] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0012] The present invention provides a method for efficiently separating iron and manganese components in iron-manganese ore, which comprises the following steps:

[0013] S1. Roasting: Mixing ferromanganese ore with an intermediate product of the vanadium industry or a vanadium product to obtain a mixed material, wherein the mixing ratio of the ferromanganese ore and the intermediate product of the vanadium industry or the vanadium product is calculated as n(MnO2) / n(V2O5), wherein MnO2 is manganese in the ferromanganese ore (calculated as MnO2), and V2O5 is vanadium in the vanadium product or the intermediate product of the vanadium industry or the vanadium product containing vanadium oxide (calculated as V2O5), and n(MnO2) / n(V2O5) is 0.5-3:1; roasting the mixed material at a high temperature to obtain a roasted clinker;

[0014] S2, leaching: leaching the roasted clinker obtained in step S1, and then filtering to obtain a manganese-containing and vanadium-containing leaching solution and an iron-containing leaching slag, wherein the iron-containing leaching slag is the separated iron product; the iron-containing leaching slag has a high iron content, reaching the standard of iron concentrate (TFe>60%), and can be directly used as a raw material for blast furnace ironmaking, and can also be used as a raw material for preparing ferroalloys;

[0015] S3, recovering vanadium: adding a vanadium precipitation additive to the manganese-containing and vanadium-containing leaching solution obtained in step S2, and adjusting the pH value for precipitation, filtering after vanadium precipitation to obtain a vanadium industry intermediate product or vanadium product and a manganese-containing supernatant;

[0016] S4, recovering manganese: the manganese-containing supernatant obtained in step S3 is precipitated or dried and crystallized, and then filtered to obtain a manganese product and a manganese extraction waste liquid.

[0017] Furthermore, the method further comprises:

[0018] S5. Utilization of iron-containing tailings: the iron-containing leached slag obtained in step S2 is directly used as a feed material for a blast furnace, or as a raw material for preparing ferroalloys;

[0019] S6. Utilization of vanadium industry intermediate products or vanadium products: the vanadium industry intermediate products or vanadium products obtained in step S3 are output as products, or the vanadium industry intermediate products or vanadium products are recycled back to the roasting system as additives to participate in the next round of roasting; the recovered vanadium industry intermediate products or vanadium products can be directly output as products, or can be recycled again as roasting additives;

[0020] S7, recycling of manganese extraction waste liquid: after impurities are removed from the manganese extraction waste liquid obtained in step S4, it is recycled back to the leaching system as the leaching medium in step S2. The impurities removed from the vanadium extraction waste liquid are ammonia and nitrogen elements.

[0021] In the method as described above, preferably, in step S1, the ferromanganese ore is a manganese ore with a Mn / Fe mass ratio of less than 3, and may be at least one of an oxide mineral, a hydrogenated mineral, a carbonate mineral, a sulfide mineral, a silicate mineral and a borate mineral, etc.; and its particle size is 200-300 meshes.

[0022] The intermediate products or vanadium products of the vanadium industry include at least one of vanadates, vanadium oxides, vanadium slag, etc. Vanadium salts include polyvanadates, ammonium metavanadate, pyrovanadates, orthovanadates, etc., specifically including ammonium polyvanadate, ammonium metavanadate, sodium metavanadate, sodium pyrovanadate, sodium orthovanadate, calcium metavanadate, calcium pyrovanadate, calcium orthovanadate, manganese metavanadate, manganese pyrovanadate, manganese orthovanadate, etc. Vanadium oxides include at least one of vanadium trioxide, vanadium dioxide, and vanadium pentoxide. Vanadium slag is an intermediate product obtained from the vanadium-titanium magnetite smelting process, and the vanadium content is 1-15% in terms of V2O5.

[0023] In the actual roasting process, the vanadium element reconstructs and transforms the insoluble manganese minerals in the iron manganese ore into acid-soluble manganese vanadate, and regulates the physical phase of the iron minerals, and then leaches them out through the acid solution to achieve efficient separation of the iron and manganese components and recycling of the roasting medium. In the above method, preferably, in step S1, the high-temperature roasting temperature is 700-1000°C, the constant temperature time is 10-300min, and the heating rate is 2-10°C / min.

[0024] In the method as described above, preferably, in step S2, leaching is performed at a liquid-solid ratio of deionized water to roasted clinker of 2 to 20:1 in mL / g, and during the leaching process, the pH value of the leaching system is controlled to be 2.0 to 3.0 by adding an acid solution, the leaching temperature is 30 to 100° C., and the leaching time is 30 to 180 min.

[0025] The acid solution is at least one of sulfuric acid, hydrochloric acid or nitric acid; the leaching can be carried out in a water bath or a heating jacket, and the iron leaching slag is repeatedly washed with water with a pH of 2.0 to 3.0 and a temperature of 20 to 100° C. until the solution is transparent.

[0026] In the method as described above, preferably, in step S3, the vanadium precipitation additive is an ammonium salt, and the ammonium salt is at least one of ammonium sulfate, ammonium carbonate or ammonium bicarbonate; the vanadium precipitation additive is added in an amount such that the molar ratio of ammonium in the ammonium salt to vanadium in the leaching solution is 1.0 to 3.0; during the vanadium precipitation process, the pH value of the system is maintained at 2 to 3 by adding acid; the acid is at least one of sulfuric acid, hydrochloric acid or nitric acid; the vanadium precipitation temperature is 60 to 100°C, and the vanadium precipitation time is 20 to 180 minutes.

[0027] According to the method as described above, preferably, in step S4, the manganese precipitate is precipitated by carbonization precipitation or direct precipitation. The carbonization precipitation method is to add at least one of carbon dioxide gas, sodium carbonate solution and ammonium carbonate solution to the manganese-containing supernatant, wherein the carbon dioxide is pure carbon dioxide gas or industrial carbon dioxide, or flue gas containing carbon dioxide released when vanadium slag is mixed with calcium salt and manganese salt and roasted; during the carbonization process, the pH value of the carbonization system is maintained at 6-8 by adding an alkaline solution; the alkaline solution is at least one of sodium hydroxide solution, ammonia water, sodium carbonate and ammonium carbonate solution; the carbonization temperature is 20-100°C; the carbonization time is 10-120min; the manganese salt obtained by carbonization precipitation is manganese carbonate; the direct precipitation method is to add an alkaline substance to the manganese-containing supernatant to maintain the pH value of the precipitation system at 7-10, the alkaline substance is at least one of sodium hydroxide solution and ammonia water; the direct precipitation temperature is 20-100°C; the precipitation time is 10-120min; the manganese salt obtained by direct precipitation is trimanganese tetraoxide.

[0028] In step S5, the drying and crystallization method is to place the manganese-containing supernatant in at least one of a rotary evaporator, a vacuum drying oven, an oven, and a centrifuge, the drying temperature is 20 to 110° C., and the drying time is 12 to 48 hours; and the manganese salt is obtained by drying and crystallizing.

[0029] (III) Beneficial effects

[0030] The method provided by the present invention for strengthening vanadium-chromium separation by co-roasting vanadium slag with calcium salt and manganese salt has the following advantages:

[0031] (1) The vanadium yield of the method of the present invention is higher than that of the existing separation process of iron and manganese in iron-manganese ore, which reflects the synergistic effect of vanadium and manganese. This is because from the low temperature stage of roasting (600°C), manganese and vanadium combine to form a stable manganese pyrovanadate phase. The phase does not change when the roasting temperature is further increased. The manganese pyrovanadate phase is easily soluble in acid solution, which can achieve efficient extraction of manganese and vanadium.

[0032] (2) The method of the present invention does not release toxic gases during the roasting process;

[0033] (3) The separation efficiency of iron and manganese in the iron-manganese ore by the method of the present invention is much higher than that of the existing iron-manganese ore separation method;

[0034] (4) The method of the present invention enriches vanadium in the slag and manganese in the leaching solution by adding a vanadium precipitation additive;

[0035] (5) The iron-containing tailings of the present invention enrich the iron in the ferromanganese ore into one phase, and its content reaches that of iron concentrate (TFe>60%), which can be directly used in blast furnace smelting of various ferroalloys;

[0036] (6) The addition of vanadium industry intermediates or vanadium products reduces the high roasting reaction temperature during the separation of iron and manganese in traditional ferromanganese ore, further saves costs, and improves the recovery rate of valuable iron and manganese components in ferromanganese ore;

[0037] (7) Due to the addition of vanadium industry intermediates or vanadium products, the problem of iron and manganese being leached together during leaching of iron-manganese ore is avoided, and the subsequent process of removing iron from manganese is reduced;

[0038] (8) The intermediate products or vanadium products used as additives in the vanadium industry can be recycled. DETAILED DESCRIPTION

[0039] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation methods.

[0040] The reaction mechanism of the present invention is:

[0041] The method provided by the present invention uses ferromanganese ore as raw material, and uses vanadium industry intermediate products or vanadium products as roasting medium, and utilizes the excellent selective binding and directional reduction ability of vanadium to manganese, so as to achieve the physical phase reconstruction of manganese minerals in ferromanganese ore into acid-soluble vanadates without changing the physical phase of iron minerals. Further, through acid leaching, efficient separation of iron and manganese and recycling of vanadium roasting medium can be achieved, which can effectively avoid the disadvantages of existing separation of iron and manganese in ferromanganese ore.

[0042] The present invention innovatively uses the intermediate product of the vanadium industry or the vanadium product as an additive to mix and roast with the ferromanganese ore, utilizes the vanadium element and the manganese element to combine in the low temperature section (600°C) to generate pyrovanadate manganese that is easily soluble in acid, and continues to increase the roasting temperature. The physical phase is still pyrovanadate manganese, the physical phase is relatively stable, and the separation and extraction of iron and manganese are achieved during the subsequent leaching. In this process, the manganese element and the vanadium element act synergistically, and neither is indispensable. It is defined that the manganese in the ferromanganese ore is calculated as MnO2, and the vanadium in the intermediate product of the vanadium industry or the vanadium product is calculated as V2O5, and the molar ratio is n(MnO2) / n(V2O5) of 0.5 to 3:1, and the reaction formula is as shown in formula (2). If n(MnO2) / n(V2O5) is less than 0.5:1, it will cause the vanadium element to react insufficiently with the elements in the ferromanganese ore to generate Fe4Mn3(VO4)6, and the reaction formula is as shown in formula (1). If n(MnO2) / n(V2O5) is greater than 3:1, there will be too little vanadium to completely react with the manganese in the iron manganese ore to form manganese pyrovanadate. The remaining manganese will combine with iron to form FeMnO3. The reaction equation is as shown in equation (3).

[0043] 8Fe2O3+6Mn2O3+12V2O5=4Fe4Mn3(VO4)6+3O2↑(1)

[0044] 2MnO2+V2O5=Mn2V2O7+O2↑(2)

[0045] 2Fe2O3+4MnO2=4FeMnO3+O2↑(3).

[0046] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation methods.

[0047] Example 1

[0048] A method for efficiently separating the iron and manganese components in the ferromanganese ore by mixing the vanadium industry intermediate product or vanadium product with the ferromanganese ore and recycling the vanadium industry intermediate product or vanadium product comprises the following steps:

[0049] (1) Calcination: grind the iron manganese ore and then screen it. The obtained iron manganese ore has a particle size of 200-250 meshes. Add vanadium pentoxide to mix the mixture, and then mix and roast it. The particle size of vanadium pentoxide is required to be 200-250 meshes so that the vanadium in vanadium pentoxide can further combine with the iron manganese ore. The manganese content in the iron manganese ore is 26.97% in terms of MnO2, and the vanadium content in vanadium pentoxide is 56.02% in terms of V2O5. The iron manganese ore and vanadium pentoxide are mixed at a molar ratio of n(MnO2) / n(V2O5) of 2.5. The mixed mixture is roasted at 850°C for 120 minutes to obtain roasted clinker, and the heating rate is 2° / min. The roasted clinker has a particle size of 250-300 meshes after crushing.

[0050] (2) Leaching: The leaching process is carried out in a water bath. Deionized water is added to the leaching container at a liquid-solid ratio of 5 mL / g to the roasted clinker. When heated to 70°C, the roasted clinker is added. The pH value of the leaching system is controlled to be about 2.2 by adding sulfuric acid with a volume fraction of 10%. The leaching temperature is 70°C. After leaching for 120 minutes, the solid-liquid separation is performed by filtration to obtain iron-containing leaching residue and manganese-containing and vanadium-containing leaching solution. The leaching residue is repeatedly rinsed with hot water with a pH value of 2.2 and a temperature of 70°C. After leaching, the contents of manganese and vanadium in the leaching solution are measured, and the vanadium leaching rate is 89.26%, wherein the vanadium leaching rate is calculated according to the formula: vanadium leaching rate = (mass of vanadium in the leaching solution) / mass of vanadium in the roasted clinker. The manganese leaching rate is 85.97%, while the iron leaching rate in the solution is only 0.00492%, that is, the leaching solution contains manganese and vanadium, and iron is enriched in the leaching residue, thus realizing the efficient separation of iron and manganese.

[0051] (3) Vanadium precipitation: The vanadium precipitation process is carried out in a water bath, and ammonium sulfate is used as a vanadium precipitation additive; the amount of vanadium precipitation additive is added according to the molar ratio of ammonium in the ammonium salt to vanadium in the leachate of 1.5; the pH value of the system is maintained at 2 by adding a sulfuric acid solution with a volume fraction of 10%; at a vanadium precipitation temperature of 95°C, after precipitation for 60 minutes, vanadium is precipitated, and the solid and liquid are filtered to separate the ammonium polyvanadate precipitate and the manganese-containing supernatant. After vanadium precipitation, the vanadium content in the manganese-containing supernatant is measured, and the vanadium precipitation rate is obtained to be 99.28%. Among them, the vanadium precipitation rate is calculated according to the following formula: vanadium precipitation rate = (mass of vanadium in the leachate - mass of vanadium in the manganese-containing supernatant) / mass of vanadium in the leachate.

[0052] (4) Obtaining vanadium product: The ammonium polyvanadate precipitate is dried at 120° C. for 12 h in advance, and then heated to 550° C. and roasted for 120 min. The obtained vanadium pentoxide has a purity of 99.23% as measured by chemical analysis. The vanadium pentoxide can be output as a vanadium pentoxide product or returned to the roasting system of step (1) to participate in the next round of roasting process.

[0053] (5) Utilization of iron-containing tailings: The iron-containing leaching slag is iron concentrate (TFe>60%), which is directly put into blast furnace smelting. The smelting atmosphere and temperature are controlled to obtain high-quality ferroalloy.

[0054] (6) Recovering manganese: introducing carbon dioxide into the manganese-containing supernatant obtained in step (3) for carbonization at a gas flow rate of 0.1 L / min; during the carbonization process, the pH value of the carbonization system is maintained at 6.8 by adding 5 g / L of sodium hydroxide solution; the carbonization temperature is 40° C.; the carbonization time is 60 min; and then filtering to separate the solid and liquid to obtain manganese carbonate precipitate and vanadium extraction waste liquid.

[0055] Alternatively, the manganese-containing supernatant obtained in step (3) is electrolyzed to obtain an electrolytic manganese product with a manganese content of >99.7%.

[0056] (7) Impurity removal: The impurities that need to be removed from the vanadium extraction waste liquid obtained in step (5) are mainly ammonia nitrogen, which is removed by chemical precipitation. After impurities are removed, the leaching medium is circulated back to the leaching system for repeated use in step (2).

[0057] Example 2

[0058] A method for efficiently separating the iron and manganese components in the ferromanganese ore by mixing the vanadium industry intermediate product or vanadium product with the ferromanganese ore and recycling the vanadium industry intermediate product or vanadium product comprises the following steps:

[0059] (1) Calcination: grind the iron manganese ore and then screen it. The obtained iron manganese ore has a particle size of 200-250 meshes. Add ammonium polyvanadate to mix the mixture, and then mix and roast it. The particle size of the ammonium polyvanadate is required to be 200-250 meshes so that the vanadium of the ammonium polyvanadate can further combine with the iron manganese ore. The manganese content in the iron manganese ore used is 26.97% in terms of MnO2, and the vanadium content in the ammonium polyvanadate is 50.50% in terms of V2O5. The iron manganese ore and the ammonium polyvanadate are mixed in a molar ratio of n(MnO2) / n(V2O5) of 2.25. The mixed mixture is evenly roasted at 850°C for 180 minutes to obtain a roasted clinker, and the heating rate is 5° / min. The roasted clinker has a particle size of 250-300 meshes after crushing.

[0060] (2) Leaching: Leaching is carried out in a water bath. Deionized water is added to the leaching container at a liquid-solid ratio of deionized water to roasted clinker of 10 mL / g. When heated to 60°C, roasted clinker is added. The pH value of the leaching system is controlled to 2.0 by adding sulfuric acid with a volume fraction of 20%. The leaching temperature is 60°C. After leaching for 120 minutes, solid-liquid separation is performed by filtration to obtain iron-containing leaching residue and manganese-containing and vanadium-containing leaching solution. The leaching residue is repeatedly rinsed with hot water with a pH value of 2.0 and a temperature of 60°C. After leaching, the contents of iron, manganese and vanadium in the manganese-containing and vanadium-containing leaching solution are determined, and the leaching rate of iron is 0.00732%, the leaching rate of manganese is 84.73%, and the leaching rate of vanadium is 86.02%, which achieves efficient separation of iron and manganese.

[0061] (3) Vanadium precipitation: The vanadium precipitation process is carried out in a water bath, and ammonium sulfate is used as a vanadium precipitation additive; the amount of vanadium precipitation additive added is based on the molar ratio of ammonium in the ammonium salt to vanadium in the leaching solution of 1.3; the vanadium precipitation process is carried out by adding a sulfuric acid solution with a volume fraction of 20% to maintain the pH value of the system at 2; the vanadium precipitation temperature is 100°C, and after precipitation for 40 minutes, vanadium is precipitated, and the solid and liquid are filtered to separate to obtain ammonium polyvanadate precipitate and manganese-containing supernatant. After vanadium precipitation, the vanadium content in the manganese-containing supernatant is measured to obtain a vanadium precipitation rate of 98.36%, and its purity is measured by chemical analysis to be 98.76%. It can be output as an ammonium polyvanadate product, or it can be returned to the roasting system of step (1) to participate in the next round of roasting process.

[0062] (4) Utilization of iron-containing tailings: The iron-containing leaching slag is iron concentrate (TFe>60%), which is directly put into blast furnace smelting. The smelting atmosphere and temperature are controlled to obtain high-quality ferroalloy.

[0063] (5) Recovering manganese: adding ammonia water to the manganese-containing supernatant obtained in step (3) to precipitate manganese ions, maintaining the pH value of the precipitation system at 8.0; the precipitation temperature is 60° C.; the precipitation time is 30 min; then filtering and separating the solid and liquid to obtain manganese tetraoxide precipitate and vanadium extraction waste liquid.

[0064] (6) Impurity removal: The impurities that need to be removed from the vanadium extraction waste liquid obtained in step (5) are mainly ammonia nitrogen, which is removed by conventional chemical precipitation method and circulated back to the leaching system as the leaching medium in step (2) after impurity removal.

[0065] Example 3

[0066] A method for efficiently separating the iron and manganese components in the ferromanganese ore by mixing the vanadium industry intermediate product or vanadium product with the ferromanganese ore and recycling the vanadium industry intermediate product or vanadium product comprises the following steps:

[0067] (1) Calcination: The iron manganese ore is ground and sieved to obtain an iron manganese ore with a particle size of 200-250 meshes, and vanadium slag is added for mixing, and then mixed and roasted. The particle size of the vanadium slag is required to be 200-250 meshes so that the vanadium in the vanadium slag can further combine with the iron manganese ore. Among them, the manganese content in the iron manganese ore used is 26.97% in terms of MnO2, and the vanadium content in the vanadium slag is 18.22% in terms of V2O5. The iron manganese ore and vanadium pentoxide are mixed at a molar ratio of n(MnO2) / n(V2O5) of 2.35. The mixed material is evenly roasted at 850°C for 120 minutes to obtain a roasted clinker, and the heating rate is 10° / min; the roasted clinker is crushed to a particle size of 250-300 meshes.

[0068] (2) Leaching: The leaching process is carried out in a heating jacket. Deionized water is added to the leaching container at a liquid-solid ratio of deionized water to roasted clinker of 3 mL / g. Roasted clinker is added at 70°C. The pH value of the leaching system is controlled to be about 2.7 by adding sulfuric acid with a volume fraction of 50%. The leaching temperature is 70°C. The leaching process time is 50 minutes. After leaching, the solid-liquid separation is carried out by filtration to obtain leaching residue and vanadium-containing leaching solution. The leaching residue is repeatedly rinsed with hot water with a pH value of 2.7 and a temperature of 70°C. After leaching, the contents of iron, manganese and vanadium in the manganese-containing and vanadium-containing leaching solution are determined, and the leaching rate of manganese is 85.45%, the leaching rate of vanadium is 87.45%, and the leaching rate of iron is 0.00412%, thereby achieving efficient separation of iron and manganese. In addition, 7.2% of the manganese in the original vanadium slag is transferred into the manganese- and vanadium-containing leaching solution after composite roasting and acid leaching. This part of manganese is also combined with the vanadium in the vanadium slag to form manganese pyrovanadate, and enters the solution through leaching, thereby realizing the recovery and utilization of part of the manganese in the vanadium slag.

[0069] (3) Vanadium precipitation: The vanadium precipitation process is carried out in a water bath, and ammonium sulfate is used as a vanadium precipitation additive; the amount of vanadium precipitation additive added is based on the molar ratio of ammonium in the ammonium salt to vanadium in the leaching solution of 2.0; the pH value of the system is maintained at 2.2 by adding a sulfuric acid solution with a volume fraction of 50%; at a vanadium precipitation temperature of 90°C, after precipitation for 90 minutes, vanadium is precipitated, and the solid and liquid are filtered to separate to obtain ammonium polyvanadate precipitate and manganese-containing supernatant. After vanadium precipitation, the vanadium content in the manganese-containing supernatant is determined to obtain a vanadium precipitation rate of 97.35%, and its purity is measured by chemical analysis to be 97.54%. It can be output as an ammonium polyvanadate product, or it can be returned to the roasting system of step (1) to participate in the next round of roasting process.

[0070] (4) Utilization of iron-containing tailings: The iron-containing leaching slag is iron concentrate (TFe>60%), which is directly put into blast furnace smelting. The smelting atmosphere and temperature are controlled to obtain high-quality ferroalloy.

[0071] (5) Recovering manganese: adding 20% ​​sodium hydroxide solution to the manganese-containing supernatant obtained in step (3) to precipitate manganese ions, maintaining the pH value of the precipitation system at about 7.0; the precipitation temperature is 40° C.; the precipitation time is 120 min; filtering and separating the solid and liquid to obtain manganese carbonate precipitate and vanadium extraction waste liquid.

[0072] (6) Utilization of manganese salt: The manganese carbonate precipitate of step (5) is oxidatively roasted at 400° C. for 12 h, during which oxygen is introduced at a flow rate of 1 L / min to obtain a crude manganese dioxide product, which is then placed in a 15% by volume sulfuric acid solution and a sodium chlorate solution for reaction for 120 min to obtain refined manganese dioxide with a manganese dioxide content of 91.98%. This product can be used as an industrial oxidant and catalyst.

[0073] (7) Impurity removal: The impurities that need to be removed from the vanadium extraction waste liquid obtained in step (3) are mainly ammonia nitrogen, which is removed by chemical precipitation and then recycled back to the leaching system as the leaching medium in step (2) after impurity removal.

[0074] Comparative Example 1

[0075] When a conventional sulfuric acid roasting-water leaching method is used to separate iron and manganese from a low-grade iron-manganese ore of manganese oxide (TFe: 30.35%, Mn: 14.30%), it is necessary to introduce not only SO2 but also a large amount of N2 during the roasting process, resulting in a large amount of gas waste; during leaching, it is inevitable that iron and manganese will be leached together, which brings a lot of difficulties to the subsequent removal of iron from manganese.

[0076] Comparative Example 2

[0077] Endophytic fungi are used to bioleach ferromanganese ore (Fe2O3: 67.90%, MnO2: 8.79%). This method requires a 20-day experiment to separate iron and manganese from the ferromanganese ore, but the manganese leaching rate is only 79%, which is much lower than the manganese leaching rate of the present invention. However, different ferromanganese ores require different types of bacteria, and the entire leaching process is slow, which greatly limits this method.

[0078] Comparative Example 3

[0079] 7wt% Na2S2O3 is added as a reducing agent to high-iron manganese oxide ore (TFe: 21.28%, Mn: 39.05%), and a reduction roasting magnetic separation method is used to separate iron and manganese from the iron manganese ore. This method not only requires a high temperature of 1100°C, which has the characteristics of high energy consumption, but also requires a vertical furnace to react, which has a complex process and high production and maintenance costs; the recovery rate of manganese is only 85.96%, which is much lower than the manganese recovery rate of the present invention.

[0080] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any person skilled in the art can use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A method for efficiently separating iron and manganese components in iron-manganese ore, characterized in that: It includes the following steps: S1. Roasting: Mixing the ferromanganese ore with the intermediate product of the vanadium industry or the vanadium product to obtain a mixed material, wherein the mixing ratio of the ferromanganese ore and the intermediate product of the vanadium industry or the vanadium product is calculated as n(MnO2) / n(V2O5), and n(MnO2) / n(V2O5) is 0.5 to 3:1; roasting the mixed material at a high temperature to obtain a roasted clinker; S2, leaching: leaching the roasted clinker obtained in step S1, and then filtering to obtain a manganese-containing and vanadium-containing leaching solution and an iron-containing leaching slag; S3, recovering vanadium: adding a vanadium precipitation additive to the manganese-containing and vanadium-containing leaching solution obtained in step S2, and adjusting the pH value for precipitation, filtering after vanadium precipitation to obtain a vanadium industry intermediate product or vanadium product and a manganese-containing supernatant; S4, recovering manganese: the manganese-containing supernatant obtained in step S3 is precipitated or dried and crystallized, and then filtered to obtain a manganese product and a manganese extraction waste liquid.

2. The method according to claim 1, characterized in that The method further comprises: S5. Utilization of iron-containing tailings: the iron-containing leached slag obtained in step S2 is directly used as a feed material for a blast furnace, or as a raw material for preparing ferroalloys; S6. Utilization of vanadium industry intermediate products or vanadium products: the vanadium industry intermediate products or vanadium products obtained in step S3 are output as products, or the vanadium industry intermediate products or vanadium products are recycled back to the roasting system as additives to participate in the next round of roasting; S7, recycling of manganese extraction waste liquid: after impurities are removed from the manganese extraction waste liquid obtained in step S4, it is recycled back to the leaching system as the leaching medium in step S2.

3. The method according to claim 1, characterized in that In step S1, the ferromanganese ore is a manganese ore with a Mn / Fe mass ratio of less than 3, and is at least one of an oxide mineral, a hydrogenated mineral, a carbonate mineral, a sulfide mineral, a silicate mineral and a borate mineral; and its particle size is 200 to 300 meshes.

4. The method according to claim 1, characterized in that In step S1, the vanadium industry intermediate product or vanadium product includes at least one of vanadate, vanadium oxide and vanadium slag.

5. The method according to claim 1, characterized in that In step S1, the high temperature calcination temperature is 700-1000°C, the constant temperature time is 10-300min, and the heating rate is 2-10°C / min.

6. The method according to claim 1, characterized in that In step S2, the leaching process is to perform leaching at a liquid-solid ratio of deionized water to roasted clinker of 2 to 20:1 in mL / g, and to control the pH value of the leaching system to 2.0 to 3.0 by adding an acid solution during the leaching process. The leaching temperature is 30 to 100° C., and the leaching time is 30 to 180 min.

7. The method according to claim 6, characterized in that In step S2, the iron-containing leached slag is repeatedly washed with water having a pH value of 2.0 to 3.0 and a temperature of 20 to 100° C. until the solution is transparent.

8. The method according to claim 1, characterized in that In step S3, the vanadium precipitation additive is an ammonium salt, and the ammonium salt is at least one of ammonium sulfate, ammonium carbonate or ammonium bicarbonate; the amount of the vanadium precipitation additive added is such that the molar ratio of ammonium in the ammonium salt to vanadium in the leaching solution is 1.0 to 3.0; during the vanadium precipitation process, the pH value of the system is maintained at 2 to 3 by adding acid; the vanadium precipitation temperature is 60 to 100° C., and the vanadium precipitation time is 20 to 180 minutes.

9. The method according to claim 1, characterized in that In step S4, the precipitation includes two methods: carbonization precipitation or direct precipitation. The carbonization precipitation method is to add at least one of carbon dioxide gas, sodium carbonate solution, and ammonium carbonate solution to the manganese-containing supernatant, and the pH value of the carbonization system is maintained at 6 to 8 by adding an alkaline solution during the carbonization process. The carbonization temperature is 20 to 100° C., and the carbonization time is 10 to 120 min. The manganese salt obtained by carbonization precipitation is manganese carbonate. The direct precipitation method is to add an alkaline substance to the manganese-containing supernatant to maintain the pH value of the precipitation system at 7 to 10, the direct precipitation temperature is 20 to 100° C., and the direct precipitation time is 10 to 120 min. The manganese salt obtained by direct precipitation is trimanganese tetraoxide.

10. The method according to claim 1, characterized in that In step S4, the drying and crystallization method is to place the manganese-containing supernatant in at least one of a rotary evaporator, a vacuum drying oven, an oven, and a centrifuge, the drying temperature is 20 to 110° C., and the drying time is 12 to 48 hours; and the manganese salt is obtained by drying and crystallization.