A method of leaching a sulphide mineral

Abstract

The application provides a sulfide mineral leaching method, and belongs to the field of non-ferrous metallurgy, specifically, the sulfide mineral is ground into powder and prepared into a slurry solution, the slurry solution is added into a pre-prepared sulfuric acid reaction solution, a pre-leaching reaction is carried out, then an oxidation leaching reaction is carried out, and finally a solid-liquid separation treatment is carried out to obtain a sulfate solution; wherein the concentration of sulfuric acid in the sulfuric acid reaction solution is 30g / L-300g / L. The sulfide mineral leaching method provided by the application can greatly improve the metal leaching rate of the sulfide mineral under normal pressure conditions, greatly reduce the configuration number of high-pressure reaction devices, and greatly reduce the leaching and purification cost of the sulfide mineral.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of non-ferrous hydrometallurgy, in particular to a leaching method of sulfide minerals. BACKGROUND

[0002] Sulfide minerals are one of the major forms of metal raw materials today, with abundant reserves. Copper and cobalt raw materials represented by sulfide copper-cobalt ore and copper-cobalt alloy, and nickel raw materials represented by high-grade nickel sulfide, high-grade nickel matte and low-grade nickel matte account for a considerable proportion in the hydrometallurgy industry, with the characteristics of relatively high metal grade and abundant reserves. Compared with other forms of minerals, the purification is more simple, so it is necessary to study the leaching process of sulfide minerals for the development of modern metallurgy.

[0003] Taking high-grade nickel matte as an example, the conventional leaching process is to crush the high-grade nickel matte, then pre-leach in a dilute sulfuric acid reaction solution under normal pressure, and acid leach a large amount of nickel element in the pre-leaching stage. Then, the slurry solution after pre-leaching is pumped into an oxygen pressure leaching kettle, and the un-leached nickel is continuously leached under high pressure and high temperature and rich oxygen conditions. Then, pure alkali is added to the solution containing nickel, iron and copper impurities after reaction to remove iron and copper by neutralization and hydrolysis, so as to achieve the purpose of purification. The purified solution is then extracted to deeply purify other impurities, and finally a high-purity sulfate solution is produced. This solution can be directly used to produce high-purity nickel series products.

[0004] The related reactions are as follows:

[0005] Ni + H2SO4 = NiSO4 + H2↑

[0006] 2Ni + 2H2SO4 + O2 = 2NiSO4 + 2H2O

[0007] 2Ni3S2 + 2H2SO4 + O2 = 4NiS + 2NiSO4 + 2H2O

[0008] NiS + 2O2 = NiSO4

[0009] Fe + H2SO4 = FeSO4 + H2↑

[0010] 4FeSO4 + O2 + 4H2O = 2Fe2O3 + 4H2SO4

[0011] Cu + O2 + H2SO4 = CuSO4 + H2O↑

[0012] 2Cu2S + 2H2SO4 + O2 = 2CuS + 2CuSO4 + 2H2O

[0013] CuS + 2O2 = CuSO4

[0014] In the method for processing high-ice nickel by the conventional processing, the pre-leaching is usually performed by using a low-concentration sulfuric acid reaction solution in the atmospheric leaching stage, the leaching rate of nickel is low, only part of the elemental nickel in the high-ice nickel can be leached out, and the leaching reaction of nickel is slow. More than 70% of the leaching reaction needs to be performed under the condition of pressurized oxygen enrichment, but such a process needs to use multi-stage pressurized leaching, a large amount of high-pressure oxygen-rich reaction equipment needs to be configured in the production and processing process of high-ice nickel, the equipment investment is large, the required electric energy is huge, and the configuration of a large amount of high-pressure oxygen-rich equipment greatly increases the safety hidden danger in the production process. After the high-pressure oxygen-rich leaching, the neutralization and hydrolysis purification are performed by using soda ash, which introduces other auxiliary material consumption, on the one hand, the production energy cost is increased, which does not meet the low-energy consumption requirement of the low-carbon demand at present, on the other hand, the introduction of new auxiliary materials may introduce new impurities, and the leaching and purification process flow of high-ice nickel is lengthened.

[0015] In view of this, the present application is proposed. SUMMARY

[0016] The present application provides a leaching method of sulfide minerals to solve the problem that the pre-leaching is performed by using a low-concentration sulfuric acid in the atmospheric leaching stage in the prior art, resulting in a low leaching rate of metals and a slow leaching reaction.

[0017] To solve the above problems, the present application adopts the following scheme:

[0018] A leaching method of sulfide minerals, first grinding the sulfide minerals into powder, and preparing a slurry solution, then adding the slurry solution into a pre-prepared sulfuric acid reaction solution for pre-leaching reaction, and then performing oxidation leaching reaction to obtain a sulfate solution.

[0019] In the sulfuric acid reaction solution, the concentration of sulfuric acid is 30g / L-300g / L.

[0020] In this scheme, the acid is prepared first and then the material is added, the sulfuric acid reaction solution is prepared in advance, and then the prepared slurry solution is added into the sulfuric acid reaction solution. The amount of acid in the initial state of the sulfuric acid reaction solution is sufficient, at this time the slurry solution is introduced into it, the slurry solution can immediately react with the sulfuric acid reaction solution, the strong oxidizing property of sulfuric acid is used to oxidize part of the metal sulfide, and then the leaching rate of metals and the rate of leaching reaction are improved.

[0021] The traditional technology is that the crushed sulfide minerals are not slurried, but directly added into dilute sulfuric acid for atmospheric leaching. In the initial stage of atmospheric leaching, the hydrophobic sulfide minerals which are not easy to be wetted by water are suspended and gathered into clusters under the support of surface tension, and the leaching effect is poor before the material is completely wetted, which needs to wait for a certain time for wetting, resulting in a low leaching reaction efficiency in the acid leaching equipment with high requirements for acid corrosion resistance, and a low leaching efficiency per unit time and per unit volume of equipment.

[0022] In addition, compared with directly introducing sulfuric acid solution into the slurry solution, the amount of the slurry solution in the early stage will be significantly greater than the amount of the sulfuric acid solution, which cannot guarantee that the slurry solution can react sufficiently and quickly, that is, cannot guarantee the oxidation effect on the sulfides of the metal in the slurry solution, thereby affecting the metal leaching rate.

[0023] If the concentration of the sulfuric acid reaction solution is too low, the oxidation effect will be poor, and if the concentration is too high and the oxidation effect is oversaturated, the raw materials for the reaction will be wasted. Therefore, in the present scheme, the concentration of sulfuric acid in the sulfuric acid reaction solution is set to 30 g / L-300 g / L. The sulfuric acid reaction solution with this concentration has a better oxidation effect, can guarantee the metal leaching rate, and can also guarantee a high utilization efficiency of the raw materials for the reaction.

[0024] In other preferred schemes, the method comprises the following steps:

[0025] Step a: slurry reaction: grinding the sulfide mineral into powder, and mixing the powder with the solution to prepare a slurry solution;

[0026] Step b: pre-leaching reaction: adding the slurry solution into a pre-prepared sulfuric acid reaction solution, and introducing oxygen to perform a pre-leaching reaction to obtain a reaction liquid;

[0027] Step c: oxidation leaching reaction: introducing oxygen into the reaction liquid to perform oxidation leaching treatment to obtain a leaching liquid and a leaching residue;

[0028] Preferably, when the sulfide mineral is at least one of nickel sulfide ore, high-grade nickel, and low-grade nickel, after the step c: oxidation leaching reaction is completed, the method further comprises step d: impurity removal treatment: performing impurity removal treatment on the leaching liquid to obtain a sulfate solution.

[0029] The leaching method of the sulfide mineral in the present scheme at least comprises the steps of slurry reaction, pre-leaching reaction, oxidation leaching reaction, and impurity removal treatment. In the present scheme, the pre-leaching reaction step is independent of the oxidation leaching step, and the pre-leaching reaction of the material is performed in the manner of preparing acid first and then adding material, which can utilize the strong oxidizing property of high-concentration sulfuric acid to oxidize part of the sulfides of the metal.

[0030] In a preferred scheme, step a is specifically: adding a solution into a slurry device provided with a stirring device, and grinding the sulfide mineral into powder once, and then injecting the powder into the slurry device in the manner of 0.4-0.8 Mpa positive pressure pneumatic conveying to prepare a slurry solution.

[0031] In a more preferred scheme, the sulfide mineral is at least one of nickel sulfide ore, copper-cobalt sulfide ore, cobalt-copper alloy, high-grade nickel, and low-grade nickel.

[0032] The device for grinding the sulfide mineral into powder once is a vertical roller mill.

[0033] Compared with the traditional ball mill, the vertical roller mill consumes less energy; at the same time, the vertical mill has higher wear-resistant material. Specifically, the processing capacity of the vertical roller mill is 15 t / (h.300KW.h), the processing capacity per unit time and energy consumption is 0.05 t / (h.KW.h), while the processing capacity of the ball mill is about 3 t / (h.100KW.h), the processing capacity per unit time and energy consumption is 0.03 t / (h.KW.h), the vertical mill consumes less energy; at the same time, the wear of the wear-resistant material (ferrous alloy material) of the vertical mill is about 5 g / t of material, while the wear of the wear-resistant material (ferrous alloy material) of the ball mill is 1500 g / t of material, the wear of the wear-resistant material of the vertical mill is greatly reduced compared with the ball mill, and the consumption of the iron purification auxiliary material is also greatly reduced.

[0034] The particle size D90 of the powder is less than or equal to 40 μm, and the smaller particle size can make the powder react more fully with sulfuric acid in the subsequent reaction and oxidation leaching reaction;

[0035] The solution mixed with the material for beating is water and / or a sulfate solution obtained after the impurity removal treatment of step d; the mass ratio of liquid to solid in the slurry is 1.5-2:1, so as to meet the requirements of subsequent steps b and c.

[0036] In other preferred schemes, when the sulfide mineral is at least one of nickel sulfide, high-grade nickel sulfide, and low-grade nickel sulfide, after the completion of the oxidation leaching reaction of step c, the method further comprises step d of impurity removal treatment: removing impurities from the leaching solution to obtain a sulfate solution.

[0037] It should be noted that the solution in step a is at least one of water, the leaching solution obtained in step c, and the sulfate solution obtained after the impurity removal treatment of step d.

[0038] In other preferred schemes, in step b, the concentration of sulfuric acid in the sulfuric acid reaction solution is 150 g / L-300 g / L;

[0039] The pre-leaching reaction temperature is 65-80℃; the purity of the oxygen is greater than 90%, and the flow rate thereof is 10-60 Nm 3 / h;

[0040] The flow rate ratio of oxygen to slurry is oxygen flow rate: slurry flow rate = (7-10 Nm 3 / h):(8-10 m 3 / h).

[0041] The concentration of sulfuric acid is increased during the pre-leaching process in step b, and the pre-leaching reaction of the material is carried out by the method of preparing acid first and then adding material. In this way, the sulfides of the metal can be oxidized at a suitable temperature (65-80℃) by using the strong oxidizing property of the higher concentration sulfuric acid than that of the conventional leaching, and a small amount of high-purity oxygen (purity greater than 90%) is added to improve the oxidation atmosphere of the pre-leaching reaction. On the one hand, the oxidation reaction of the sulfides in the sulfide minerals is accelerated, and the intergranular structure of the sulfides such as nickel sulfide and copper sulfide is destroyed to the greatest extent. On the other hand, the leaching reaction of the elemental metal in the sulfide minerals is accelerated, thereby indirectly increasing the reaction rate of the oxidized sulfides at normal pressure and the leaching rate of the metal.

[0042] In other preferred schemes, in step b, after the addition of the slurry solution, the pre-leaching reaction time is 1.2-1.8 times the time of adding the prepared slurry solution in step a into the pre-leaching reaction device; and after the addition of the slurry solution, the pre-leaching reaction time is 0.8-1.5 h. In this scheme, the pre-leaching time is 1.2-1.8 times the time of adding the slurry solution, mainly to maximize the release of hydrogen.

[0043] In other preferred schemes, in step b, the amount of the slurry solution added is calibrated by the amount of sulfuric acid in the pre-leaching reaction device, and the amount of the slurry solution added is based on the mass of the sulfide minerals in the slurry solution; the volume V of the slurry solution added is V=M / N;

[0044] wherein M is the mass of the sulfide minerals in the slurry solution to be added, and N is the mass percentage of the sulfide minerals in the unit volume of the slurry solution; M=(the mass of the sulfuric acid in the pre-leaching reaction device×the molar mass of the elemental metal / the molar mass of the sulfuric acid)×1.05 / 【1-(the mass percentage of sulfur in the sulfide minerals×the molar mass of the elemental metal / the molar mass of the elemental sulfur) / the metal content of the sulfide minerals】.

[0045] In other preferred schemes, the step c of the oxidative leaching includes a normal pressure leaching process and a pressurized leaching process; the oxidative leaching reaction device includes a normal pressure leaching reaction device and a pressurized leaching reaction device; the leaching solution is divided into a first leaching solution and a second leaching solution; and the leaching residue is divided into a first leaching residue and a second leaching residue.

[0046] The normal pressure leaching process specifically includes: subjecting the reaction solution to a normal pressure oxidative leaching reaction, and introducing oxygen during the reaction; the reaction time of the normal pressure oxidative leaching reaction is 2-13 h; and after the reaction is completed, the slurry solution is separated to obtain a first leaching solution and a first leaching residue. The normal pressure leaching has a high safety factor and small investment, and can reduce the load and investment of the pressurized leaching.

[0047] wherein the purity of the oxygen is greater than 90%; and the flow rate ratio of the oxygen and the first leaching residue slurry solution is oxygen flow rate: first leaching residue slurry solution flow rate=(7-10 Nm 3 / h):(8-10 m3 The atmospheric leaching reaction temperature is 60-90℃.

[0048] In this scheme, the oxygen flow, the slurry liquid flow, the slurry liquid solid ratio, and the sulfuric acid reaction solution concentration are all accurately calculated and designed in advance, accurately dosed, and the alkaline characteristics of the material itself are used to consume hydrogen ions, and the material itself is used as a neutralizing agent for neutralization and hydrolysis to remove iron and purify the reaction, which shortens the process flow and reduces the addition of auxiliary materials.

[0049] In other preferred schemes, the atmospheric leaching reaction device is configured with a stirring reactor of a super-energy oxidizer;

[0050] In the atmospheric leaching process, the stirring speed of the stirring reactor is 50-120 r / min, the slurry liquid flows out from the upper part of the stirring reactor and flows into the super-energy oxidizer, and then the slurry liquid and oxygen are mixed in the super-energy oxidizer, and then the mixture is injected into the stirring reactor from the bottom of the stirring reactor, and the cycle is repeated, so that the oxygen and the material are in full contact.

[0051] This process method is configured with a super-energy oxidizer for atmospheric oxidation leaching using ultrasonic oxygen dispersion, on the one hand, high-purity oxygen is used for oxidation reaction, on the other hand, ultrasonic wave is used to greatly increase the dispersion effect of oxygen, at the same time, the material is ground to 40 microns or less, greatly increasing the specific surface area of the material and the contact area with oxygen, which can greatly increase the reaction rate of atmospheric oxidation of sulfide and the leaching rate of metal.

[0052] In other preferred schemes, the pressure leaching process is as follows: the first leaching residue obtained by atmospheric leaching reaction is slurried with water to become a first leaching residue slurry, and then is transported into a pressure leaching reaction device containing a sulfuric acid reaction solution, and after the pressure leaching reaction is completed, solid-liquid separation is performed to obtain a second leaching liquid and a second leaching residue;

[0053] The first leaching residue is slurried with water for 0.5-2h; the concentration of sulfuric acid in the sulfuric acid reaction solution in the pressure leaching reaction is 30g / L-150g / L; the internal pressure of the pressure leaching reaction device is 1-2Mpa; after the temperature in the pressure oxidation leaching reactor is increased to the initial reaction temperature of 80-110℃, the pressure oxidation reaction starts to react vigorously, and the reaction temperature is maintained at 140-180℃ by the heat released by the reaction until the pressure oxidation reaction is completed, and the pressure leaching time is 2-5h.

[0054] In other preferred schemes, step d is specifically as follows: the second leaching liquid is transported into a impurity removal reaction device, iron powder is added, and the slurry liquid after the iron powder replacement copper removal reaction is subjected to solid-liquid separation to obtain a sulfate solution; wherein the pH in the impurity removal reaction device is 1-2, and the temperature is 60-80℃.

[0055] Compared with the prior art, the present application has the following beneficial effects:

[0056] First, the equipment and pipeline for water slurry have low requirements for acid corrosion resistance, while the acid leaching process has greater requirements for the equipment, and requires greater equipment investment. The present application can save the subsequent acid leaching time, improve the acid leaching efficiency, and improve the leaching efficiency of the acid leaching equipment per unit time by pre-water slurry.

[0057] Second, the concentration of sulfuric acid is increased in the pre-leaching process, and the material pre-leaching reaction is carried out by the method of preparing acid first and then adding material. The strong oxidizing property of the high-concentration sulfuric acid is used to oxidize part of the sulfides of the metal, and oxygen is supplemented to improve the oxidation atmosphere of the pre-leaching reaction. On the one hand, the oxidation reaction of the sulfides in the sulfide minerals is accelerated, and on the other hand, the leaching reaction of the elemental metal in the sulfide minerals is accelerated.

[0058] Third, by using the method of preparing acid first and then adding material, the thick slurry liquid added to the acid solution is rapidly diluted, and the oxygen gas blown in can also rapidly diffuse into the entire reaction system. The material can rapidly react with the acid and the blown-in oxygen gas, thereby improving the leaching efficiency.

[0059] Fourth, the present process method configures a super-energy oxidizer for atmospheric oxidation leaching using ultrasonic oxygen dispersion. On the one hand, high-purity oxygen is used for oxidation reaction, and on the other hand, the dispersion effect of oxygen is greatly increased by using ultrasonic waves. At the same time, the material is ground to a particle size of 40 microns or less, greatly increasing the specific surface area of the material and the contact area with oxygen, increasing the reaction rate of the atmospheric oxidation of sulfides and the leaching rate of metals. The leaching rate of metals in sulfide minerals under atmospheric conditions can reach more than 60%.

[0060] Fifth, the present process method precisely configures the ingredients during atmospheric leaching reaction, utilizes the alkaline characteristics of the material itself to consume hydrogen ions, and uses the material itself as a neutralizing agent for neutralization and hydrolysis to remove iron and purify. The content of impurities such as iron and copper in the first leaching solution is extremely low, which shortens the process flow, reduces the addition of auxiliary materials, and reduces the processing cost of sulfide minerals.

[0061] Sixth, the present process method greatly reduces the number of high-pressure reaction equipment configurations in the process of processing sulfide minerals. Compared with the conventional process method, the number of high-pressure reaction equipment configurations in the present method is reduced by more than 60%, greatly reducing the fixed investment.

[0062] Seventh, the present process greatly compresses the pressure oxidation leaching purification process of sulfide mineral processing in the process of processing sulfide minerals, greatly reduces the consumption of auxiliary materials, and reduces the processing cost of sulfide minerals.

[0063] In summary, the process can greatly improve the leaching rate of sulfide minerals under normal pressure, greatly reduce the number of high-pressure reaction devices, and greatly reduce the leaching and purification cost of sulfide minerals. BRIEF DESCRIPTION OF DRAWINGS

[0064] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0065] Figure 1 A specific leaching process flow chart of sulfide minerals is provided for the present application.

[0066] Figure 2 A filtrate-related parameter statistical chart for example 4 and comparative examples 1-7 of the present application. DETAILED DESCRIPTION

[0067] In order to make the above and other features and advantages of the present application clearer, the following further describes the present application with reference to the drawings. It should be understood that the specific embodiments given herein are for the purpose of explanation and are only exemplary, but are not limiting.

[0068] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0069] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application. However, it is apparent to those skilled in the art that the present application can be practiced without specific details, which are not required to practice the present application. In other cases, well-known steps or operations are not described in detail so as not to obscure the present application.

[0070] In order to embody the advantages of the method provided by the present application, the following will be described with reference to specific examples.

[0071] Example 1 (nickel sulfide ore)

[0072] Step a slurry reaction: 4.05 tons of nickel sulfide ore containing 50% nickel, 0.1% copper, 4% iron and 18% sulfur is ground into a powder with a D90 of 40 microns using a vertical roller mill, and 8 m 3 of water is added to a slurry tank with the stirring device turned on to prepare a slurry solution with a liquid-solid ratio of 2:1 for standby.

[0073] Step b pre-leaching reaction: 8 m 3 of the impurity removal treatment output sulfate solution, 4 m 3 of water and concentrated sulfuric acid are prepared into a nickel-containing sulfuric acid reaction solution with a sulfuric acid concentration of 100 g / L in the pre-leaching reaction tank, the stirring device of the pre-leaching reaction tank is started, and the prepared solution is warmed to 75°C for standby.

[0074] The prepared slurry solution is uniformly added to the pre-leaching reaction tank, and the pre-leaching reaction is carried out. During the pre-leaching reaction process, 7 m 3 of oxygen (oxygen purity is 95%, same below) is passed, and the slurry solution is added while the oxygen is passed. The flow ratio of oxygen and slurry solution is controlled at oxygen flow: slurry flow = (7 Nm 3 / h):(8 m 3 / h). After the slurry solution is added, the pre-leaching reaction time is 1.5 times the time of adding the slurry solution into the pre-leaching reaction device.

[0075] Step c oxidation leaching reaction: the reaction solution in the pre-leaching reaction tank after the pre-leaching reaction is transported to the atmospheric leaching reaction device, the stirring reactor is started, the stirring speed of the stirring reactor is 100 r / min, the oxygen valve is opened, and the super-energy oxidizer of the oxidation leaching reaction tank is started. The slurry solution flows out from the upper part of the stirring reactor and flows into the super-energy oxidizer, where it is mixed with oxygen, and then flows into the stirring reactor from the bottom of the stirring reactor, and so on, so that the oxygen and the material are fully contacted, and the reaction is carried out for 3 hours. After pressure filtration, 15.7 m 3 of first leaching solution and 3.15 tons of first leaching residue are obtained; the pH of the first leaching solution is 5.0, the nickel concentration is 92 g / L, the iron concentration is 0.005 g / L, the copper concentration is 0.002 g / L, and the nickel leaching rate is 52%; the main components of the first leaching residue are NiS, Fe(OH)3 and Cu(OH)2.

[0076] The first leaching residue is added to a slurry tank containing 2 m 3 of water and slurry for 1 h, and then the first leaching residue slurry solution is transported to a slurry tank containing 12 m 3The pressure oxidation leaching reaction device of the sulphate reaction solution with a sulphuric acid concentration of 50 g / L; the gas pressure in the pressure oxidation leaching reaction kettle is raised to 1.6 MPa by high-pressure oxygen, the steam valve of the pressure oxidation leaching reaction kettle is opened, the temperature in the pressure oxidation leaching reaction kettle is raised to 100°C, and then the pressure oxidation reaction starts violently, the steam valve is closed, the reaction temperature is maintained at 165°C by relying on the heat released by the reaction itself, oxygen is continuously introduced to maintain the gas pressure in the reaction kettle, the reaction is completed after 3 hours, pressure filtration is performed, and the second leaching solution and the second leaching residue are obtained. The second leaching solution is 12 m 3 The second leaching residue contains nickel at 109 g / L, the second leaching residue contains nickel at 4.07%, contains iron at 52.03%, the dry weight is about 0.76 tons, and the nickel comprehensive leaching rate is 98.9%.

[0077] Step d: impurity removal treatment: the second leaching solution is transported into the iron powder displacement copper removal reaction kettle; the stirring device of the iron powder displacement copper removal reaction kettle is opened, 50 kg of iron powder is quantitatively added according to the copper content of the second leaching solution, and the iron powder displacement copper removal reaction is performed, and the reaction is performed for 1 hour.

[0078] The sulphate solution in which the iron powder displacement copper removal reaction in the iron powder displacement copper removal reaction kettle is completed is transported to the iron powder displacement copper removal filtration device, filtration is performed, and a sulphate solution is obtained, and the solution contains copper at 0.01 g / L.

[0079] Example 2 (copper cobalt sulphide ore)

[0080] Step a: slurry reaction: 4.05 tons of copper cobalt sulphide ore containing copper at 30%, iron at 20%, cobalt at 15%, and sulphur at 13% is ground into powder with D90 reaching 30 microns by using a vertical roller mill, water 8 m 3 is added to the slurry kettle under the condition that the stirring device is opened, and the slurry liquid is prepared for use by using a liquid-solid ratio of 2:1.

[0081] Step b: pre-leaching reaction: the sulphate solution produced by the impurity removal treatment is 8 m 3 (containing cobalt at 28 g / L and copper at 16 g / L), water 4 m 3 and concentrated sulphuric acid are prepared into a cobalt copper-containing sulphate reaction solution with a sulphuric acid concentration of 100 g / L in the pre-leaching reaction kettle, the stirring device of the pre-leaching reaction kettle is started, and the prepared solution is warmed to 80°C for standby.

[0082] The prepared slurry liquid is uniformly added to the pre-leaching reaction kettle, and the pre-leaching reaction is performed. During the pre-leaching reaction process, oxygen is introduced at a gas flow rate of 10 m 3 / h, the slurry liquid is added while the oxygen is introduced, and the flow rate ratio of oxygen to slurry liquid is controlled to be oxygen flow rate: slurry liquid flow rate = (10 Nm 3 / h):(10 m 3 / h), the pre-dipping reaction time is 1.2 times of the time for adding the whole slurry solution into the pre-dipping reaction device.

[0083] Step c: oxidation leaching reaction: the reaction solution in which the pre-dipping reaction is completed in the pre-dipping reactor is transported into the atmospheric leaching reaction device, the stirring reactor is opened, the stirring rate of the stirring reactor is 80 r / min, the oxygen valve is opened, the super-energy oxidizer of the oxidation leaching reactor is opened, the slurry solution flows into the super-energy oxidizer from the upper part of the stirring reactor, the slurry solution and oxygen are mixed in the super-energy oxidizer, and then the mixture is injected into the stirring reactor from the bottom of the stirring reactor for reaction for 13 hours. After filtration, the first leaching solution 18 m 3 and the first leaching residue are obtained; the pH of the first leaching solution reaches 2.0, the copper concentration is 46.01 g / L, the cobalt concentration is 26.2 g / L, the iron concentration is 3.05 g / L, the copper leaching rate is 54%, and the cobalt leaching rate is 65%.

[0084] The first leaching residue is added into the slurry tank containing 8 m 3 of water for slurry for 1 h, and then the first leaching residue slurry solution is transported into the pressurized oxidation leaching reaction device containing 12 m 3 of sulfuric acid reaction solution with a sulfuric acid concentration of 90 g / L; the gas pressure in the pressurized oxidation leaching reactor is increased to 2.0 MPa by using high-pressure oxygen, the steam valve of the pressurized oxidation leaching reactor is opened, the temperature in the pressurized oxidation leaching reactor is increased to 80°C, the pressurized oxidation reaction starts to react violently, the steam valve is closed, the reaction temperature is maintained at 180°C by relying on the heat released by the reaction itself, and oxygen is continuously introduced to maintain the gas pressure in the reactor, and the reaction is completed after 5 hours. After filtration, the second leaching solution and the second leaching residue are obtained. Among them, the second leaching solution is 17 m 3 , the copper concentration in the second leaching solution is 40.12 g / L, the cobalt concentration is 14.31 g / L, the second leaching residue contains 1% of copper, 0.5% of cobalt, and 48.06% of iron, the dry weight is about 2.5 tons, the comprehensive copper leaching rate is 98.4%, and the comprehensive cobalt leaching rate is 98.3%.

[0085] Example 3 (cobalt-copper alloy)

[0086] Step a: slurry reaction: 2.0 tons of cobalt-copper alloy containing 5.5% of cobalt, 70% of copper, 18% of iron, and 2% of sulfur is ground into powder with D90 reaching 35 microns by using a vertical roller mill, 4 m 3 of water is added into the slurry tank with the stirring device opened, the powder is added into the slurry tank by using the positive pressure pneumatic conveying method at 0.6 MPa, and a slurry solution with a solid content of more than 30% is prepared by using a liquid-solid ratio of 2:1 for standby.

[0087] Step b: pre-dipping reaction: the sulfate solution produced by the impurity removal treatment 8 m 3CuSO4.5H2O 0.5 kg, CoSO4.7H2O 0.05 kg, H2O 8 m 3 The cobalt-containing copper sulphate reaction solution with a sulphuric acid concentration of 180 g / L was prepared in the pre-leaching reactor using the concentrated sulphuric acid and cobalt-containing copper, and the stirring device of the pre-leaching reactor was started. The prepared solution was heated to 65°C for standby.

[0088] The prepared slurry was uniformly added to the pre-leaching reactor, and pre-leaching reaction was carried out. The pre-leaching reaction process was controlled at 9 m 3 / h of oxygen flow. The oxygen and slurry flow ratio was controlled at oxygen flow: slurry flow = (9 Nm 3 / h):(9 m 3 / h) while adding the slurry, and the pre-leaching reaction time was 1.8 times of the time for adding the slurry into the pre-leaching reactor.

[0089] Step c: oxidation leaching reaction: the reaction solution in which the pre-leaching reaction was completed in the pre-leaching reactor was transported to the atmospheric leaching reactor, the stirring device of the reactor was started, the stirring speed was 50 r / min, the oxygen valve was opened, the super energy oxidizer of the oxidation leaching reactor was started, the slurry flowed out from the upper part of the stirring reactor and flowed into the super energy oxidizer, the slurry and oxygen were mixed in the super energy oxidizer, and then the mixture was injected into the stirring reactor from the bottom of the stirring reactor, and the reaction was carried out for 2.1 hours. Pressure filtration was carried out to obtain the first leaching solution 15.7 m 3 and the first leaching residue 1.1 t. The pH of the first leaching solution was 3.0, the copper concentration was 70.01 g / L, the cobalt concentration was 5.94 g / L, the iron concentration was 2.5 g / L, the copper leaching rate was 90.9%, and the cobalt leaching rate was 98.0%.

[0090] The first leaching residue was added to the slurry tank containing 2 m 3 of water for slurry for 1 h, and then the first leaching residue slurry was transported to the pressure oxidation leaching reactor containing the sulphuric acid reaction solution with a sulphuric acid concentration of 8 m 3 The gas pressure in the pressure oxidation leaching reactor was increased to 1.0 MPa by using high-pressure oxygen, the steam valve of the pressure oxidation leaching reactor was opened, the temperature in the pressure oxidation leaching reactor was increased to 110°C, and then the pressure oxidation reaction was started. The steam valve was closed, the reaction temperature was maintained at 140°C by relying on the heat released by the reaction, oxygen was continuously introduced to maintain the gas pressure in the reactor, and the reaction was carried out for 2 hours. Pressure filtration was carried out to obtain the second leaching solution and the second leaching residue. The second leaching solution was 7.5 m 3 , the copper concentration in the second leaching solution was 17.6 g / L, the cobalt concentration was 0.22 g / L, the second leaching residue contained 1% of copper, the filter residue contained 0.1% of cobalt, and the dry weight of the filter residue was about 0.78 tons. The cobalt comprehensive leaching rate was 99.4%, and the copper comprehensive leaching rate was 99.5%.

[0091] Example 4 (High-ice nickel)

[0092] Step a slurry reaction: 4.05 tons of high-ice nickel particles produced by pyrometallurgical smelting, containing 65% nickel, 8% copper, 3% iron, and 18% sulfur, were ground into powder with a D90 of 20 microns using a vertical roller mill. Water was added to the slurry tank at a rate of 8 m 3 / hour to prepare a slurry solution with a solid content of more than 30% at a liquid-to-solid ratio of 2:1 for use.

[0093] Step b pre-leaching reaction: 8 m 3 of sulfate solution produced by impurity removal treatment, 4 m 3 of water, and concentrated sulfuric acid were mixed in the pre-leaching reactor to prepare a nickel-containing sulfuric acid reaction solution with a concentration of 204 g / L for use. The pre-leaching reactor was started and the prepared solution was heated to 70°C for use.

[0094] The prepared slurry solution was uniformly added to the pre-leaching reactor, and the pre-leaching reaction was carried out. Oxygen was passed into the pre-leaching reactor at a rate of 8 m 3 / hour. The slurry solution was added while oxygen was being passed in, and the flow rate ratio of oxygen to slurry solution was controlled at oxygen flow rate: slurry solution flow rate = (8 Nm 3 / hour):(9 m 3 / hour). The pre-leaching reaction time was 1.2 times the time it took to add the slurry solution to the pre-leaching reactor.

[0095] Step c oxidation leaching reaction: the reaction solution from the pre-leaching reactor was transferred to the atmospheric leaching reactor. The stirring rate of the stirring reactor was set to 120 r / min, the oxygen valve was opened, and the super-energy oxidizer of the oxidation leaching reactor was started. The slurry solution flowed out of the top of the stirring reactor, entered the super-energy oxidizer, mixed with oxygen in the super-energy oxidizer, and then flowed into the stirring reactor from the bottom. This cycle was repeated to ensure that the oxygen and the material were in full contact. The reaction was carried out for 3 hours. After pressure filtration, 17.5 m 3 of first leaching solution and 2.87 tons of first leaching residue were obtained. The pH of the first leaching solution was 5.0, the nickel concentration was 128 g / L, the iron concentration was 0.011 g / L, the copper concentration was 0.008 g / L, and the nickel leaching rate was 64.13%.

[0096] The first leaching residue was added to a slurry tank containing 2 m 3 of water and slurred for 1 hour to obtain a first leaching residue slurry solution, which was then transferred to a slurry tank containing 12 m 3The pressure oxidation leaching reaction device of the sulphate reaction solution with a sulphuric acid concentration of 100 g / L; the gas pressure in the pressure oxidation leaching reaction kettle is raised to 1.6 MPa by high-pressure oxygen, the steam valve of the pressure oxidation leaching reaction kettle is opened, the temperature in the pressure oxidation leaching reaction kettle is raised to 110°C, and then the pressure oxidation reaction starts violently, the steam valve is closed, the reaction temperature is maintained at 165°C by relying on the heat released by the reaction itself, oxygen is continuously introduced to maintain the gas pressure in the reaction kettle, the reaction is completed after 3 hours, pressure filtration is performed, and the second leaching solution and the second leaching residue are obtained. The second leaching solution is 11 m 3 The nickel concentration in the second leaching solution is 109 g / L, the second leaching residue contains 4.07% nickel and 52.03% iron, the dry weight is about 0.76 tons, and the comprehensive leaching rate of nickel is 99.1%.

[0097] Step d: impurity removal treatment: the second leaching solution is transported into the iron powder displacement copper removal reaction kettle; the stirring device of the iron powder displacement copper removal reaction kettle is opened, 550 kg of iron powder is quantitatively added according to the copper content of the second leaching solution, and the iron powder displacement copper removal reaction is performed for 1 hour.

[0098] The sulphate solution in which the iron powder displacement copper removal reaction in the iron powder displacement copper removal reaction kettle is completed is transported to the iron powder displacement copper removal filtration device, filtration is performed, and a sulphate solution containing 0.03 g / L of copper is obtained.

[0099] Example 5 (low nickel)

[0100] Step a: slurry reaction: 4.05 tons of low nickel produced by pyrometallurgical smelting containing 30% nickel, 2% copper, 36% iron, and 7% sulfur are ground into powder with a D90 of 40 microns using a vertical roller mill, 8 m 3 of water is added to the slurry kettle with the stirring device turned on to prepare a slurry solution with a solid content of more than 30% at a liquid-solid ratio of 2:1.

[0101] Step b: pre-leaching reaction: 8 m 3 of the sulphate solution produced by impurity removal treatment (with a nickel concentration of 58.5 g / L), 4 m 3 of water, and concentrated sulphuric acid are prepared into a nickel-containing sulphate reaction solution with a sulphuric acid concentration of 100 g / L in the pre-leaching reaction kettle, the stirring device of the pre-leaching reaction kettle is started, and the prepared solution is warmed to 75°C for standby.

[0102] The prepared slurry solution is uniformly added to the pre-leaching reaction kettle, and the pre-leaching reaction is performed. During the pre-leaching reaction process, 7 m 3 of oxygen is introduced per hour, the oxygen is introduced while adding the slurry solution, and the flow ratio of oxygen to slurry solution is controlled at oxygen flow: slurry solution flow = (7 Nm 3 / h):(8 m 3 / h), the pre-dipping reaction time is 1.3 times of the time for adding the whole slurry solution into the pre-dipping reaction device.

[0103] Step c: oxidation leaching reaction: the reaction solution in which the pre-dipping reaction is completed in the pre-dipping reactor is transported into the atmospheric leaching reaction device, the stirring device of the reactor is started, the stirring rate of the stirring device is 110 r / min, the oxygen valve is opened, the super energy oxidizer of the oxidation leaching reactor is started, the slurry solution flows into the super energy oxidizer from the upper part of the stirring reactor, the slurry solution and oxygen are mixed in the super energy oxidizer, and then the mixture is injected into the stirring reactor from the bottom of the stirring reactor, and the reaction is carried out for 4 hours. After filtration, the first leaching solution 18 m 3 and the first leaching residue 2.34 t are obtained. The pH of the first leaching solution is 5.0, the concentration of nickel is 60 g / L, the concentration of iron is 0.038 g / L, the concentration of copper is 0.005 g / L, and the nickel leaching rate is 61%.

[0104] The first leaching residue is added into the slurry tank containing 2 m 3 of water for slurry for 1 h, and then the first leaching residue slurry solution is transported into the pressurized oxidation leaching reaction device containing 12 m 3 of sulfuric acid solution with a concentration of 50 g / L of sulfuric acid. The gas pressure in the pressurized oxidation leaching reactor is increased to 1.4 MPa by using high-pressure oxygen, the steam valve of the pressurized oxidation leaching reactor is opened, the temperature in the pressurized oxidation leaching reactor is increased to 90°C, and then the pressurized oxidation reaction starts violently. The steam valve is closed, the reaction temperature is maintained at 155°C by relying on the heat released by the reaction itself, and oxygen is continuously introduced to maintain the gas pressure in the reactor. The reaction is carried out for 3.5 hours, and then filtration is carried out to obtain the second leaching solution and the second leaching residue. The second leaching solution is 12 m 3 , the concentration of nickel in the second leaching solution is 57 g / L, the second leaching residue contains 1.2% of nickel and 50.08% of iron, the dry weight is about 2.88 tons, and the comprehensive nickel leaching rate is 97.9%.

[0105] Step d: impurity removal treatment: the second leaching solution is transported into the iron powder replacement copper removal reactor; the stirring device of the iron powder replacement copper removal reactor is started, 200 kg of iron powder is quantitatively added according to the copper content of the second leaching solution, and the iron powder replacement copper removal reaction is carried out for 1 hour.

[0106] The sulfate solution in which the iron powder replacement copper removal reaction in the iron powder replacement copper removal reactor is completed is transported into the iron powder replacement copper removal filtration device, and filtration is carried out to obtain a sulfate solution containing 0.01 g / L of copper.

[0107] The following examples and comparative examples are used to demonstrate the effects of the present application. For the purpose of uniform comparison, the following comparative examples are compared with Example 4.

[0108] Comparative Example 1 (sulfuric acid addition sequence)

[0109] A comparative experiment was conducted using high-grade nickel matte as an example. The difference between this comparative example and Example 4 is that in the pretreatment step, the slurry was added first, followed by the slow addition of sulfuric acid (in Example 4, acid was added first, followed by the slurry). The first leachate produced by atmospheric pressure oxidation leaching was 14.5 ml. 3 The pH was 1.5, the nickel concentration was 96.01 g / L, the iron concentration was 3.36 g / L, the copper concentration was 14.04 g / L, and the overall nickel leaching rate was 39.8%.

[0110] By comparing with Example 4, it can be seen that when the slurry is added to water first, and then concentrated sulfuric acid is added, the overall sulfuric acid concentration of the reaction system is basically at a low level after the addition order of sulfuric acid and slurry changes. The sulfuric acid concentration of the system is low throughout the reaction process, and the oxidizing power is low, which is not conducive to the oxidation of sulfides in high-grade nickel matte. As a result, the nickel leaching rate drops significantly from 64.13% to 39.8%.

[0111] Comparative Example 2 (Grinding particle size did not meet requirements)

[0112] A comparative experiment was conducted using high-grade nickel matte as an example. The difference from Example 4 is that the material was ground into fine particles with a D90 of 130 micrometers and then slurried. The first leachate produced by atmospheric pressure leaching was 13.5 ml. 3 The pH value reached 1.05, the nickel concentration was 89.6 g / L, the iron concentration was 4.56 g / L, the copper concentration was 12.89 g / L, and the overall nickel leaching rate was 34.5%.

[0113] By comparing with Example 4, it can be seen that the finer the particle size, the larger the specific surface area, the larger the reaction contact area, and the faster the reaction rate. At the same time, the finer the particle size, the more favorable it is for the leaching of metallic nickel encapsulated by sulfides. That is, the smaller the particle size of high-grade nickel matte particles, the more favorable it is for the oxidative leaching of nickel.

[0114] Comparative Example 3 (Oxidizing Agent)

[0115] To investigate the effect of different oxidants on the leaching rate of nickel, Comparative Example 3 used air as the oxidant to carry out the reaction process of atmospheric pressure oxidation leaching.

[0116] The difference lies in the fact that air is used instead of oxygen as the oxidant in the atmospheric and pressurized processes, and the first leachate produced by atmospheric leaching is 15m. 3 The pH value reached 0.89, the nickel concentration was 96.7 g / L, the iron concentration was 6.75 g / L, the copper concentration was 8.44 g / L, and the overall nickel leaching rate was 41.33%.

[0117] By comparison with Example 4, it can be seen that the efficiency of using high-purity oxygen as oxidant is higher than that of using air as oxidant, because: in air, there are not only oxidants such as oxygen, but also other reducing gases and protective inert nitrogen, which are not conducive to the oxidation of sulfides, and the air flow is large, which is not conducive to the dispersion and dissolution of the gas, and the use of pure oxygen as oxidant not only has strong oxidizing property, but also can reduce the gas volume, which is conducive to the dispersion and dissolution of oxygen in the reaction system, thereby accelerating the oxidation leaching rate of sulfides in high-ice nickel.

[0118] Comparative Example 4 (oxygen dispersion mode)

[0119] In order to study the influence of different oxygen dispersion modes on the leaching rate of nickel, Comparative Example 15 directly introduces oxygen into the atmospheric oxidation leaching reactor to carry out atmospheric oxidation leaching.

[0120] The difference is that the ultrasonic oxidizer is removed in the atmospheric leaching process, and oxygen is directly introduced into the atmospheric oxidation leaching reactor to carry out atmospheric oxidation leaching reaction, and the first leaching liquid 15m 3 , the detection pH reaches 4.5, the nickel concentration is 104.3 g / L, the iron concentration is 0.045 g / L, the copper concentration is 0.15 g / L, and the comprehensive leaching rate of nickel is 44.6%.

[0121] By comparison with Example 4, it can be seen that the oxidation leaching rate of the ultrasonic oxidizer is about 20% higher than that of the conventional oxygen introduction, because: the ultrasonic oxidizer utilizes the high-frequency vibration of ultrasonic waves, which is conducive to the dispersion and dissolution of oxygen bubbles, can greatly increase the oxygen dissolution rate and gas dissolution rate of the solution system, and is conducive to improving the reaction speed of the oxidation leaching reaction.

[0122] Comparative Example 5 (sulfuric acid addition amount)

[0123] In order to study the influence of different sulfuric acid addition amounts on the purification reaction of copper and iron, the reaction process under different sulfuric acid addition amounts.

[0124] The difference is that the sulfuric acid addition amount in the pretreatment process of Comparative Example 5 is adjusted to 2.8t, and the first leaching liquid 14.5m 3 , the detection pH reaches 1.02, the nickel concentration is 130.4 g / L, the iron concentration is 3.45 g / L, the copper concentration is 9.12 g / L, and the comprehensive leaching rate of nickel is 65.1%.

[0125] By comparison with Example 4, it can be seen that when the amount of sulfuric acid added is greater than the theoretical amount, the pH at the end of the reaction is too low, and a large amount of iron and copper is leached from the solution, resulting in an increase in impurities in the leaching solution. The reason is that sulfuric acid can only be consumed by metallic nickel, and the oxidation leaching of nickel sulfide does not consume sulfuric acid. When the amount of sulfuric acid added is excessive, the excess sulfuric acid will consume copper, iron and other acid-consuming impurities, resulting in an increase in impurities in the leaching solution, and the purpose of selective leaching cannot be achieved.

[0126] Comparative Example 6 (adding dilute sulfuric acid)

[0127] In order to study the effect of different sulfuric acid concentrations on the nickel leaching rate under the same total amount of sulfuric acid added.

[0128] The difference is that the concentration of the nickel-containing sulfuric acid solution in Comparative Example 6 is 120 g / L. The first leaching solution produced in the atmospheric leaching process is 17.5 m 3 , the detection pH reaches 4.5, the nickel concentration is 101 g / L, the iron concentration is 0.03 g / L, the copper concentration is 0.05 g / L, and the comprehensive nickel leaching rate is 50.6%.

[0129] By comparison with Example 4, it can be seen that a too low concentration of sulfuric acid solution will affect the nickel leaching rate.

[0130] Comparative Example 7 (leaching time combination)

[0131] In order to study the effect of leaching time on the leaching rate under the same conditions.

[0132] The difference is that the pre-leaching time in Comparative Example 7 is 0.5 h. The first leaching solution produced in the atmospheric leaching process is 17.5 m 3 , the detection pH reaches 5.0, the nickel concentration is 115 g / L, the iron concentration is 0.02 g / L, the copper concentration is 0.005 g / L, and the comprehensive nickel leaching rate is 57.6%.

[0133] By comparison with Example 4, it can be seen that the oxidation reaction rate of the raw material is affected, the nickel leaching rate is reduced, and ultimately the comprehensive nickel leaching rate is reduced.

[0134] The pH value, nickel concentration, iron concentration, copper concentration and nickel leaching rate of the first leaching solution filtrate in Example 4 and Comparative Examples 1-7 are recorded in Table 1, and a graph is drawn according to Table 1 Figure 2 .

[0135] Table 1: Statistical table of related parameters of the first leaching solution in Example 4 and Comparative Examples 1-7

[0136]

[0137] The traditional process is pre-leaching in the atmospheric leaching stage, and the leaching rate of nickel is low. Only part of the elemental nickel in high nickel matte can be leached out. More than 70% of the leaching reaction needs to be leached under the condition of pressurized oxygen enrichment. The multi-stage pressurized leaching needs to use a large number of high-pressure oxygen-rich reaction equipment in the production and processing process of high nickel matte, which requires large equipment investment and huge electric energy. At the same time, the configuration of a large number of high-pressure oxygen-rich equipment greatly increases the safety hazard of the production process. After high-pressure oxygen-rich leaching, pure alkali needs to be used for neutralization and hydrolysis purification, which introduces other auxiliary material consumption. On the one hand, it increases the production energy cost, which does not meet the low energy consumption requirement of today's low carbon demand. On the other hand, the introduction of new auxiliary materials may introduce new impurities, and at the same time, it lengthens the leaching and purification process flow of high nickel matte.

[0138] Compared with the traditional technology, the present application greatly improves the leaching rate of metal under atmospheric conditions in the process of processing sulfide minerals. The leaching rate of sulfide mineral metal under atmospheric conditions can reach more than 52%. The present application greatly reduces the configuration number of high-pressure reaction equipment in the process of processing sulfide minerals. Compared with the conventional process method, the configuration number of high-pressure reaction equipment in the present application is reduced by more than 60%, which greatly reduces the fixed investment. The present application greatly compresses the leaching and purification process flow of sulfide mineral processing, greatly reduces the auxiliary material consumption, and reduces the processing cost of sulfide minerals.

[0139] In summary, the present process can greatly improve the leaching rate of sulfide mineral metal under atmospheric conditions, greatly reduce the configuration number of high-pressure reaction device, and greatly reduce the leaching and purification cost of sulfide minerals.

[0140] Although the embodiments of the present application have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the present application. Those skilled in the art can make changes, modifications, replacements and variations to the above-mentioned embodiments within the scope of the present application.

Claims

1. A method of leaching a sulphide mineral, characterised by, The method comprises the following steps: The step a slurry reaction: grinding the sulfide mineral into powder, and mixing the powder with a solution to prepare a slurry solution; The step b pre-leaching reaction: adding the slurry solution into a pre-prepared sulfuric acid reaction solution, and introducing oxygen to perform a pre-leaching reaction to obtain a reaction solution; The step c oxidative leaching reaction: introducing oxygen into the reaction solution to perform an oxidative leaching treatment to obtain a leaching solution and a leaching residue; The step d impurity removal treatment: performing an impurity removal treatment on the leaching solution to obtain a sulfate solution; The concentration of sulfuric acid in the sulfuric acid reaction solution is 150 g / L-300 g / L; After the slurry solution is added, the pre-leaching reaction time is 1.2-1.8 times of the time for adding the slurry solution into the pre-leaching reaction device; The solution is water and / or the sulfate solution obtained after the impurity removal treatment; The sulfide mineral is at least one of nickel sulfide ore, high-grade nickel ore, and low-grade nickel ore.

2. The method of leaching a sulphide mineral according to claim 1, characterised in that, The step a is specifically: adding a solution into a slurry device provided with a stirring device, and then injecting the powder into the slurry device in a 0.4-0.8 Mpa positive pressure pneumatic conveying manner to prepare the slurry solution; The device for grinding the sulfide mineral into powder is a vertical roller mill; The particle size D90 of the powder is less than or equal to 40 μm; The mass ratio of liquid to solid in the slurry solution is 1.5-2:1; The solution in the step a is at least one of water, the leaching solution obtained in the step c oxidative leaching reaction, and the sulfate solution obtained after the impurity removal treatment in the step d.

3. The method of leaching a sulphide mineral according to claim 1 or 2, characterised in that, The pre-leaching reaction temperature in the step b is 65-80℃; The purity of the oxygen is greater than 90%, and the flow rate thereof is 10-60 Nm³ / h; The flow rate ratio of the oxygen to the slurry solution is oxygen flow rate: slurry solution flow rate=(7-10 Nm³ / h):(8-10 m³ / h).

4. The method of leaching a sulphide mineral according to claim 1 or 2, characterised in that, The step c comprises an atmospheric leaching process and a pressure leaching process; The leaching solution is divided into a first leaching solution and a second leaching solution, and the leaching residue is divided into a first leaching residue and a second leaching residue.

5. The method for leaching of sulfidic minerals according to claim 4, characterized in that, The atmospheric leaching process is specifically: performing an atmospheric oxidative leaching reaction on the reaction solution, introducing oxygen during the reaction process, and the reaction time of the atmospheric oxidative leaching reaction is 2-13 h, and after the reaction is completed, the first leaching solution and the first leaching residue are separated; The purity of the oxygen is greater than 90%, the flow rate ratio of the oxygen to the first leaching residue slurry solution is oxygen flow rate: first leaching residue slurry solution flow rate=(7-10 Nm³ / h):(8-10 m³ / h), and the temperature of the slurry solution is 60-90℃.

6. The method of leaching a sulphide mineral according to claim 5, characterised in that, The atmospheric leaching reaction device is provided with a stirring reactor of an ultra-energy oxidizer; During the atmospheric leaching process, the stirring rate of the stirring reactor is 50-120 r / min, the slurry solution flows out from the upper part of the stirring reactor, flows into the ultra-energy oxidizer, and is mixed with oxygen in the ultra-energy oxidizer, and then is injected into the stirring reactor from the bottom of the stirring reactor.

7. The method of leaching a sulphide mineral according to claim 4, characterised in that, The pressure leaching process is specifically as follows: the first leaching residue obtained by the atmospheric leaching reaction is pulped into a first leaching residue slurry by adding water, and then is delivered into a pressure leaching reaction device containing the sulfuric acid reaction solution, and after the pressure leaching reaction is completed, solid-liquid separation is performed to obtain the second leaching liquid and the second leaching residue; In the pressure leaching reaction, the concentration of sulfuric acid in the sulfuric acid reaction solution is 30 g / L-150 g / L; the internal pressure of the pressure leaching reaction device is 1-2 MPa, the initial temperature of the pressure leaching reaction is 80-110 ℃, the temperature of the pressure leaching reaction is 140-180 ℃, and the time of the pressure leaching reaction is 2-5 h.

8. The method of leaching a sulphidic mineral according to claim 7, characterised in that, The step d is specifically as follows: the second leaching liquid is delivered into a impurity removal reaction device, iron powder is added, and slurry after the iron powder replacement copper removal reaction is completed is subjected to solid-liquid separation to obtain a sulfate solution; In the impurity removal reaction device, the pH is 1-2, and the temperature is 60-80 ℃.

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