Treatment method of nickel sulfate solution

Abstract

The invention provides a treatment method of a nickel sulfate solution, and relates to the technical field of non-ferrous metal smelting. The treatment method of the nickel sulfate solution comprises a neutralization procedure, an extraction and oil removal procedure, an electrodeposition procedure and a nickel deposition procedure, in the neutralization procedure, a nickel deposition material generated by anolyte deposition in the nickel deposition procedure serves as a neutralizer to adjust the pH value back, and the solution obtained after neutralization and impurity removal is subjected to extraction, oil removal and electrodeposition to obtain anolyte. And continuously precipitating the anolyte to obtain a nickel precipitation material. The first solid produced by the treatment method of the nickel sulfate solution can be used for pyrogenic production of high matte nickel and electrodeposition procedures, part of impurities in raw materials can be discharged out of a system through the first solid, no dangerous waste residue is produced, and therefore the number of needed filter presses, the number of solid residue filter pressing times and the residue discharging workload are reduced. As calcium powder is not used for neutralization in the neutralization process, the problem of pipeline blockage caused by precipitation of saturated calcium is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of nonferrous metal smelting, and in particular to a method for treating a nickel sulfate solution. Background Art

[0002] In the related art, calcium powder is generally used to adjust the pH value of nickel sulfate solution for neutralization and impurity removal, which further introduces impurity calcium and easily causes the problem of calcium saturation precipitation and pipeline blockage during liquid transfer.

[0003] In addition, the nickel-iron intermediates produced by neutralization and impurity removal are generally recovered by acid washing, value adjustment and impurity removal, and solid-liquid separation in the industry. The metal nickel is removed by open circuit impurities, the treatment process is complicated, and there is a problem of internal circulation of impurities. Moreover, the impurity removal slag is a hazardous waste with high treatment costs. Summary of the invention

[0004] The purpose of the present application is to provide a method for treating a nickel sulfate solution, aiming to solve the problem that the existing nickel sulfate solution neutralization and impurity removal introduces impurity calcium and the process of nickel recovery generates hazardous waste.

[0005] To achieve the above objectives, the present application provides a method for treating a nickel sulfate solution, comprising:

[0006] A neutralization step, adding a nickel-based neutralizing agent to the nickel sulfate solution to remove impurities, thereby obtaining a first solution and a first solid;

[0007] An extraction and degreasing step, wherein the first solution is subjected to nickel soap extraction and degreasing to obtain a degreasing solution;

[0008] The electrowinning process is to electrowinning the degreasing solution to obtain an anolyte and an electrowinning nickel plate;

[0009] In the nickel precipitation process, sodium hydroxide and / or sodium carbonate are added to the anode liquid to obtain a nickel precipitation material after precipitation; the nickel precipitation material is used as a nickel-based neutralizer.

[0010] In some embodiments, it also includes:

[0011] A pickling step, wherein the first solid is subjected to pickling and solid-liquid separation to obtain a second solution and a second solid;

[0012] In the smelting process, the second solid is smelted with a sulfiding agent and a reducing agent in an oxygen-containing atmosphere to obtain high-grade nickel matte.

[0013] In some embodiments, at least one of the following conditions is met:

[0014] A. The nickel content of the second solid is 10%-20%;

[0015] B. The mass ratio of the second solid to the sulfur element in the sulfiding agent and the reducing agent is 1:(0.03-0.04):(0.08-0.12);

[0016] C. The vulcanizing agent is sulfur or sulfide;

[0017] D. The reducing agent is coke powder, bituminous coal or anthracite;

[0018] E. At least 80wt% of the reducing agent can pass through an 80-mesh sieve;

[0019] F. Melting temperature is 1200℃-1600℃;

[0020] G. The composition of high-grade nickel matte includes: Ni 60%-73%, Co 1%-2%, Cu 3%-8%, Fe 4-10%, S18%-23%;

[0021] H. The components of the nickel sulfate solution include Ni 60-120 g / L, Co 3-21 g / L, Mn 3-21 g / L, Cu 0.1-3 g / L, Cr 100-300 mg / L, Fe 500-2000 mg / L, Al 300-1000 mg / L, Si 100-1000 mg / L, Ca 100-600 mg / L, and Mg 1-6.5 g / L.

[0022] In some embodiments, the extraction and oil removal process comprises:

[0023] A first saponification step, saponifying the first extractant and the nickel-precipitated material to obtain a first nickel soap organic phase;

[0024] A first extraction step, contacting the first solution with the first nickel soap organic phase for extraction to obtain a third solution;

[0025] In the first deoiling step, the third solution is brought into contact with the nickel-precipitated material to remove the oil, thereby obtaining a fourth solution and a third solid.

[0026] In some embodiments, the extraction and oil removal step further comprises:

[0027] A second saponification step, saponifying the second extractant and the nickel-precipitated material to obtain a second nickel soap organic phase;

[0028] a second extraction step, contacting the fourth solution with the second nickel soap organic phase for extraction to obtain a fifth solution;

[0029] The second deoiling step is to contact the fifth solution with the nickel-precipitated material to remove oil, thereby obtaining a sixth solution and a fourth solid, wherein the sixth solution is the deoiling solution.

[0030] In some embodiments, the nickel-precipitated material saponified with the first extractant includes the third solid; and the nickel-precipitated material saponified with the second extractant includes the fourth solid.

[0031] In some embodiments, at least one of the following conditions is met:

[0032] A. The saponification temperature is 45-65℃;

[0033] B. the first extractant is selected from P204;

[0034] C. the second extractant is selected from P507;

[0035] D. The nickel content in the second nickel soap organic phase and the first nickel soap organic phase is independently 6-12 g / L.

[0036] In some embodiments, at least one of the following conditions is met:

[0037] A. The oil content of the fourth solution and the sixth solution is ≤5 mg / L;

[0038] B. The components of the fifth solution include: Ni 70-120 g / L, Co 5-24 mg / L, Mn 0.01-2 mg / L, Cu 0.01-2 mg / L, Cr ≤ 1 mg / L, Fe 0.01-1 mg / L, Al 0.1-1 mg / L, Si 20-50 mg / L, Ca 0.1-3 mg / L, Mg 1-300 mg / L, and oil 10-50 mg / L.

[0039] In some embodiments, at least one of the following conditions is met:

[0040] A. The pH value of the impurity removal process is 4.0-6.0;

[0041] B. The temperature of the impurity removal process is 65-80℃;

[0042] C. Dry mass of the nickel-based neutralizer (t): Volume of the nickel sulfate solution (m 3 )=1:60~300;

[0043] D. The components of the first solution include: Ni 65-110 g / L, Co 3-20 g / L, Mn 3-20 g / L, Cu 0.1-2 g / L, Cr 1-50 mg / L, Fe 0.1-50 mg / L, Al 1-50 mg / L, Si 20-80 mg / L, Ca 100-550 mg / L, Mg 1-6 g / L;

[0044] E. The first solid includes: nickel hydroxide, iron-silicon-aluminum precipitate and manganese dioxide.

[0045] In some embodiments, the method for preparing the nickel sulfate solution includes: adding acid and anolyte to nickel cobalt hydroxide for leaching.

[0046] Compared with the prior art, the beneficial effects of this application include:

[0047] The processing method of the nickel sulfate solution provided in the present application includes a neutralization process, an extraction and oil removal process, an electrolysis process and a nickel precipitation process. The neutralization process uses the nickel precipitation material produced by the precipitation of the anolyte in the nickel precipitation process as a neutralizer to adjust the pH value. The solution after neutralization and impurity removal is extracted, deoiled, and electrolyzed to obtain the anolyte, and the anolyte is further precipitated to obtain the nickel precipitation material. The first solid produced by the processing method of the nickel sulfate solution of the present application can be used for the pyrometallurgical production of high-grade nickel matte. The electrolysis process and some impurities in the raw materials can be discharged through the first solid discharge system, and no hazardous waste residue is produced, thereby reducing the number of required filter presses and the number of solid residue filtration times, as well as the workload of slag unloading. Since the neutralization process does not use calcium powder for neutralization, the problem of saturated calcium precipitation blocking the pipeline is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope of the present application.

[0049] Figure 1 A schematic flow chart of an embodiment of a method for treating a nickel sulfate solution of the present application;

[0050] Figure 2 The figure is a flow chart of another embodiment of the method for treating nickel sulfate solution of the present application. DETAILED DESCRIPTION

[0051] As used herein:

[0052] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0053] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0054] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0055] In these examples, wt% refers to weight percentage, and unless otherwise specified, the percentages are based on mass.

[0056] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0057] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0058] In the present application, nickel cobalt hydroxide (MHP) refers to a nickel intermediate, which can be obtained by acid leaching, impurity removal, precipitation and other processes of laterite nickel ore, sulfide ore and other nickel-containing wastes. Depending on the source, nickel cobalt hydroxide contains nickel (Ni), and may contain metal elements such as cobalt (Co), manganese (Mn), iron (Fe), chromium (Cr), aluminum (Al), calcium (Ca), magnesium (Mg), and copper (Cu).

[0059] In the related art, calcium powder is generally used to adjust the pH value of nickel sulfate solution for neutralization and impurity removal. This step introduces impurity calcium, which can easily cause calcium saturation precipitation during liquid transfer and other processes, resulting in pipeline blockage.

[0060] In addition, the nickel-iron intermediates produced by neutralization and impurity removal are generally recovered by acid washing, value adjustment and impurity removal, and solid-liquid separation to remove metallic nickel and open-circuit impurities. This method has a complicated processing flow and the problem of internal circulation of impurities. The impurity removal slag is a hazardous waste and has a high processing cost.

[0061] Based on the above problem, the present application embodiment provides a method for treating a nickel sulfate solution. Figure 1 ,include:

[0062] S100: a neutralization step, adding a nickel-based neutralizing agent to the nickel sulfate solution to remove impurities, thereby obtaining a first solution and a first solid;

[0063] S200: extraction and degreasing step, extracting and degreasing the first solution through nickel soap to obtain a degreasing solution;

[0064] S300: an electrolytic process, wherein the degreasing solution is electrolytically deposited to obtain an anolyte and an electrolytic nickel plate;

[0065] S400: nickel precipitation process, adding sodium hydroxide and / or sodium carbonate into the anode liquid, and obtaining nickel precipitation material after precipitation; the nickel precipitation material is used as a nickel-based neutralizing agent.

[0066] The processing method of the nickel sulfate solution provided in the embodiment of the present application includes a neutralization process, an extraction and oil removal process, an electrolytic process and a nickel precipitation process. The neutralization process uses the nickel precipitation material produced by the precipitation of the anolyte in the nickel precipitation process as a neutralizer to adjust the pH value. The solution after neutralization and impurity removal is extracted, deoiled, and electrolytically deposited to obtain the anolyte, and the anolyte continues to precipitate to obtain the nickel precipitation material. The first solid produced by the processing method of the nickel sulfate solution of the present application can be used for the pyrometallurgical production of high-grade nickel matte. The electrolytic process and some impurities in the raw materials can be discharged through the first solid discharge system, and no hazardous waste residue is produced, thereby reducing the number of required filter presses and the number of solid residue filter presses, as well as the workload of slag unloading. Since the neutralization process does not use calcium powder for neutralization, the problem of saturated calcium precipitation blocking the pipeline is reduced.

[0067] The nickel sulfate solution in S100 can be obtained by dissolving nickel cobalt hydroxide (MHP) with sulfuric acid. It is understandable that the nickel sulfate solution in S100 can also be obtained by dissolving nickel raw materials such as nickel cobalt sulfide, nickel powder, and nickel-containing waste with sulfuric acid, or by dissolving high nickel matte with sulfuric acid to remove iron. The nickel sulfate solution also contains unreacted sulfuric acid.

[0068] Optionally, the preparation method of the nickel sulfate solution of the present application includes: adding acid and anolyte to nickel cobalt hydroxide for leaching. Exemplarily, the composition of the nickel sulfate solution includes Ni60-120g / L, Co 3-21g / L, Mn 3-21g / L, Cu 0.1-3g / L, Cr 100-300mg / L, Fe500-2000mg / L, Al 300-1000mg / L, Si 100-1000mg / L, Ca100-600mg / L, Mg 1-6.5g / L.

[0069] In some embodiments, the pH value of the impurity removal process in step S100 is 4.0-6.0, for example, it can be 4.0, 4.2, 4.5, 4.7, 4.9, 5.0, 5.3, 5.5, 5.8, 6.0 or any value between 4.0 and 6.0. The temperature of the impurity removal process is 65-80°C, for example, it can be 65°C, 70°C, 75°C, 80°C or any value between 65-80°C.

[0070] In some embodiments, the impurity removal process in step S100 includes: according to the dry basis mass (t) of the nickel-based neutralizer: the volume (m 3 )=1:60~300, a nickel-based neutralizing agent is added to neutralize the nickel sulfate solution to obtain a first solution and a first solid.

[0071] In some embodiments, the first solution obtained in step S100 includes: Ni 65-110 g / L, Co 3-20 g / L, Mn 3-20 g / L, Cu 0.1-2 g / L, Cr 1-50 mg / L, Fe 0.1-50 mg / L, Al 1-50 mg / L, Si 20-80 mg / L, Ca 100-550 mg / L, Mg 1-6 g / L. The first solid includes: nickel hydroxide, iron silicon aluminum precipitate and manganese dioxide.

[0072] In some embodiments, the extraction and oil removal process S200 includes:

[0073] S210: a first saponification step, saponifying the first extractant and the nickel precipitation material to obtain a first nickel soap organic phase;

[0074] S220: a first extraction step, contacting the first solution with the first nickel soap organic phase for extraction to obtain a third solution;

[0075] S230: a first deoiling step, wherein the third solution is brought into contact with the nickel precipitation material to remove the oil, thereby obtaining a fourth solution and a third solid.

[0076] In the above embodiment, the third solid includes a nickel-precipitated material and an extractant adsorbed by the nickel-precipitated material.

[0077] In some embodiments, step S230 further includes:

[0078] S240: a second saponification step, saponifying the second extractant and the nickel-precipitated material to obtain a second nickel soap organic phase;

[0079] S250: a second extraction step, contacting the fourth solution with the second nickel soap organic phase for extraction to obtain a fifth solution;

[0080] S260: a second deoiling step, contacting the fifth solution with the nickel precipitating material to remove oil, thereby obtaining a sixth solution and a fourth solid, wherein the sixth solution is a deoiled solution.

[0081] In the above embodiment, the fourth solid includes a nickel-precipitated material and an extractant adsorbed by the nickel-precipitated material.

[0082] The residual extract contains a certain amount of oil (including extractant), and oil removal is required before the electrolytic deposition process. The most common oil removal method in the relevant technology is activated carbon oil removal. Although activated carbon can remove oil, the amount of activated carbon used is large and the regeneration cost is high; and the activated carbon (including extractant) after oil removal is a hazardous solid waste, and its disposal cost is high. The embodiment of the present application uses nickel precipitation material for oil removal, and no activated carbon solid waste is produced. The nickel precipitation material after oil adsorption is returned to saponification to achieve the recovery of the extractant and avoid the loss of the extractant.

[0083] In the above embodiment, there are multiple ways to contact the third solution with the nickel-precipitated material for degreasing. For example, the third solution and the nickel-precipitated material can be mixed for degreasing, or the third solution can be passed through a filter cake containing the nickel-precipitated material for degreasing. Similarly, there are multiple ways to contact the fifth solution with the nickel-precipitated material for degreasing. For example, the fifth solution and the nickel-precipitated material can be mixed for degreasing, or the fifth solution can be passed through a filter cake containing the nickel-precipitated material for degreasing.

[0084] In some embodiments, the nickel-precipitated material saponified with the first extractant in step S210 includes a third solid; and the nickel-precipitated material saponified with the second extractant in step S240 includes a fourth solid.

[0085] The saponification process is completed by direct reaction of the nickel precipitated material in S400, the third solid or the fourth solid and the extractant, the process is simple, there is almost no residual solid after saponification, no filtration is required, and the equipment investment is small. When the third solid or the fourth solid is used with the extractant for saponification, the extractant contained in the third solid and the fourth solid can be recovered, and there is almost no loss of the extractant in this step.

[0086] In some embodiments, the saponification temperature is 45-65°C, for example, 45°C, 50°C, 55°C, 60°C, 65°C, or any value between 45-65°C.

[0087] In some embodiments, the first extractant is selected from P204; the second extractant is selected from P507.

[0088] In some embodiments, the nickel content in the second nickel soap organic phase and the first nickel soap organic phase is independently 6-12 g / L, for example, it can be 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, 11 g / L, 12 g / L or any value between 6-12 g / L.

[0089] In some embodiments, the oil content of the fourth solution obtained in step S230 and the sixth solution obtained in step S260 is ≤5 mg / L, for example, it can be 1 mg / L, 2 mg / L, 3 mg / L, 4 mg / L, 5 mg / L or any value ≤5 mg / L.

[0090] In some embodiments, the components of the fifth solution in step S250 include: Ni 70~120g / L, Co 5~24mg / L, Mn 0.01~2mg / L, Cu 0.01~2mg / L, Cr≤1mg / L, Fe 0.01~1mg / L, Al 0.1~1mg / L, Si 20~50mg / L, Ca 0.1~3mg / L, Mg 1~300mg / L, and oil 10~50mg / L.

[0091] In some embodiments, see Figure 2 , after step S100, further comprising:

[0092] S500: Acid washing step, acid washing the first solid and performing solid-liquid separation to obtain a second solution and a second solid;

[0093] S600: Smelting process, smelting the second solid with a sulfiding agent and a reducing agent in an oxygen-containing atmosphere to obtain high-grade nickel matte.

[0094] In the above embodiment, the second solid obtained after the first solid is subjected to the acid washing process is subjected to pyrometallurgical smelting with a sulfiding agent and a reducing agent. The first solid produced in the neutralization process takes away the impurities in the system. At the same time, because the first solid is used as a raw material for the pyrometallurgical process, a portion of nickel can be retained in the first solid without repeated washing, thereby reducing the number of required filter presses and the workload of slag unloading.

[0095] In some embodiments, acid washing the first solid includes stirring and washing the first solid with a dilute acid solution having a pH of 1.5 to 2.0, and the dilute acid solution may be a dilute sulfuric acid solution.

[0096] In some embodiments, the nickel content in the second solid of step S500 is 10%-20%, for example, it can be 10%, 12%, 13%, 15%, 17%, 19%, 20% or any value between 10% and 20%.

[0097] In some embodiments, in step S600, the mass ratio of the second solid, the sulfur element in the sulfiding agent, and the reducing agent is 1:(0.03-0.04):(0.08-0.12).

[0098] In some embodiments, the sulfiding agent is sulfur or sulfide; the reducing agent is coke powder, bituminous coal or anthracite.

[0099] In some embodiments, at least 80 wt % of the reducing agent can pass through an 80-mesh sieve.

[0100] In some embodiments, the melting temperature is 1200°C-1600°C, for example, it can be 1200°C, 1250°C, 1300°C, 1350°C, 1400°C, 1450°C, 1500°C, 1550°C, 1600°C or any value between 1200°C and 1600°C.

[0101] In some embodiments, the composition of high nickel matte includes: Ni 60%-73%, Co 1%-2%, Cu 3%-8%, Fe 4-10%, S 18%-23%.

[0102] In some embodiments, sodium hydroxide (meets GB / T209-2018) is added to the anode liquid in the nickel precipitation process, and the obtained nickel precipitation material includes nickel hydroxide.

[0103] In some embodiments, sodium carbonate (meeting GB / T210-2022) is added to the anode liquid in the nickel precipitation process, and the obtained nickel precipitation material includes nickel carbonate.

[0104] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0105] Example 1

[0106] Embodiment 1 provides a method for treating a nickel sulfate solution, comprising the following steps:

[0107] The MHP raw material was added to the anode solution and sulfuric acid for leaching to obtain the nickel sulfate solution: Ni 68g / L, Co 3.2g / L, Mn 3.2g / L, Cu 3.0g / L, Cr 100mg / L, Fe 500mg / L, Al 300mg / L, Si 100mg / L, Ca100mg / L, Mg1.0g / L.

[0108] In the neutralization process, a nickel-based neutralizing agent (nickel precipitation material containing nickel hydroxide) is added to the nickel sulfate solution to adjust the pH value to 4.0, and the process temperature is controlled at about 65°C. After stabilization for a period of time, the solid-liquid separation is carried out to obtain a first solid and a first solution (crude nickel sulfate solution). The components of the first solution are: Ni 65g / L, Co 3g / L, Mn 3g / L, Cu 1.0g / L, Cr 50mg / L, Fe 50mg / L, Al50mg / L, Si 80mg / L, Ca 100mg / L, and Mg 1.0g / L.

[0109] In the pickling process, the first solid is added with a dilute acid solution with a pH value of 1.5 to 2.0 and stirred for a period of time, and then the solid and liquid are separated to obtain a second solid and a second solution. The second solution is returned to the system for use. The second solid components include: Ni 10%, Co 0.5%, Cu 1%, and Fe 3.5%.

[0110] In the smelting process, the second solid, sulfur and coke powder are put into a blowing furnace at a ratio of 1:0.04:0.12, and oxygen-rich air is introduced. The nickel matte is smelted at 1200°C to obtain high-grade nickel matte. The composition of the high-grade nickel matte includes: Ni 60%, Co 1%, Cu 6%, Fe 10%, and S23%.

[0111] The extraction and oil removal process includes:

[0112] In the first saponification step, the first extractant P204 and the nickel-precipitated material containing nickel hydroxide are saponified at 45° C. to obtain a first nickel soap organic phase, wherein the nickel content in the first nickel soap organic phase is 6.5 g / L.

[0113] In the first extraction step, the first solution and the first nickel soap are organically extracted in a volume ratio of 1:2, and the obtained raffinate is the third solution. The third solution contains elements such as nickel, cobalt, and magnesium, and impurities such as manganese, copper, iron, and calcium are extracted into the organic phase.

[0114] In the first deoiling step, nickel precipitate material containing nickel hydroxide is added to the third solution, and the slurry is stirred to remove oil. The nickel hydroxide adsorbs organic matter. After solid-liquid separation, a third solid (containing adsorbed organic matter) and a fourth solution are obtained. The organic phase content of the fourth solution is 3.6 mg / L.

[0115] In the second saponification step, the second extractant P507 and the nickel-precipitated material containing nickel hydroxide are saponified at 45° C. to obtain a second nickel soap organic phase, and the nickel content of the second nickel soap organic phase is 6 g / L.

[0116] In the second extraction step, the fourth solution and the second nickel soap are organically extracted in a volume ratio of 1:3, and elements such as cobalt and magnesium are extracted into the organic phase. The obtained extract residue is the fifth solution. The components of the fifth solution are: Ni 70g / L, Co 24mg / L, Mn 2mg / L, Cu 2mg / L, Cr 1mg / L, Fe 1mg / L, Al 1mg / L, Si 50mg / L, Ca 3mg / L, Mg 300mg / L, and oil 10mg / L.

[0117] In the second deoiling step, nickel precipitate material containing nickel hydroxide is added to the fifth solution, and the mixture is stirred to remove oil, and a fourth solid and a sixth solution are obtained after solid-liquid separation. The organic phase content of the sixth solution is 3.5 mg / L.

[0118] In the electrolytic process, the sixth solution is pumped into the electrolytic tank, and after electrolytic deposition, an anolyte and an electrolytic nickel plate are obtained.

[0119] In the nickel precipitation process, liquid alkali is added to the anode liquid to precipitate and obtain a nickel precipitation material containing nickel hydroxide.

[0120] Example 2

[0121] Embodiment 2 provides a method for treating a nickel sulfate solution, comprising the following steps:

[0122] The MHP raw material was added to the anolyte and sulfuric acid for leaching to obtain the nickel sulfate solution: Ni 100g / L, Co 10g / L, Mn 10g / L, Cu 3g / L, Cr 200mg / L, Fe 1000mg / L, Al 600mg / L, Si 600mg / L, Ca 300mg / L, Mg4g / L.

[0123] In the neutralization process, a nickel-based neutralizing agent (nickel precipitation material containing nickel carbonate) is added to the nickel sulfate solution to adjust the pH value to 5.0, and the process temperature is controlled at about 70°C. After stabilization for a period of time, the solid-liquid separation is carried out to obtain a first solid and a first solution (crude nickel sulfate). The components of the first solution are: Ni 95g / L, Co 9g / L, Mn 9g / L, Cu 2g / L, Cr 10mg / L, Fe 5mg / L, Al 10mg / L, Si 35mg / L, Ca 288mg / L, and Mg 3.9g / L.

[0124] In the pickling process, the first solid is added with a dilute acid solution with a pH value of 1.5 to 2.0 and stirred for a period of time, and then the solid and liquid are separated to obtain a second solid and a second solution. The second solution is returned to the system for use. The second solid components include: Ni 14%, Co 0.5%, Cu 2.0%, and Fe 5%.

[0125] In the smelting process, the second solid, sulfur and bituminous coal are put into a blowing furnace at a ratio of 1:0.035:0.1, and oxygen-rich air is introduced. The nickel matte is smelted at 1350°C to obtain high-grade nickel matte. The composition of the high-grade nickel matte includes: Ni 65%, Co 1%, Cu 8%, Fe 6%, and S20%.

[0126] The extraction and oil removal process includes:

[0127] In the first saponification step, the first extractant P204 and the nickel-precipitated material containing nickel carbonate are saponified at 55° C. to obtain a first nickel soap organic phase, wherein the nickel content in the first nickel soap organic phase is 10 g / L.

[0128] In the first extraction step, the first solution and the first nickel soap are organically extracted in a volume ratio of 1:3, and the resulting raffinate is the third solution. The third solution contains elements such as nickel, cobalt, and magnesium, and impurities such as manganese, copper, zinc, iron, and calcium are extracted into the organic phase.

[0129] In the first deoiling step, the third solution is passed through a nickel carbonate-containing nickel precipitation material filter cake to remove oil, and nickel hydroxide adsorbs organic matter. After solid-liquid separation, a third solid (containing adsorbed organic matter) and a fourth solution are obtained. The organic phase content of the fourth solution is 5.0 mg / L.

[0130] In the second saponification step, the second extractant P507 and the nickel-precipitated material containing nickel carbonate are saponified at 45° C. to obtain a second nickel soap organic phase, and the nickel content of the second nickel soap organic phase is 10 g / L.

[0131] In the second extraction step, the fourth solution and the second nickel soap are organically extracted in a volume ratio of 1:4, and elements such as cobalt and magnesium are extracted into the organic phase. The obtained extract residue is the fifth solution. The components of the fifth solution are: Ni 100g / L, Co 10mg / L, Mn 1mg / L, Cu 1mg / L, Cr 0.5mg / L, Fe0.5mg / L, Al 0.5mg / L, Si 30mg / L, Ca 2mg / L, Mg100mg / L, and oil 20mg / L.

[0132] In the second deoiling step, nickel precipitate material containing nickel carbonate is added to the fifth solution, and the mixture is stirred and slurried to remove oil. After solid-liquid separation, a fourth solid and a sixth solution are obtained. The organic phase content of the sixth solution is 4.5 mg / L.

[0133] In the electrolytic process, the sixth solution is pumped into the electrolytic tank, and after electrolytic deposition, an anolyte and an electrolytic nickel plate are obtained.

[0134] In the nickel precipitation process, soda ash is added to the anode liquid to precipitate and obtain a nickel precipitation material containing nickel hydroxide.

[0135] Example 3

[0136] Embodiment 3 provides the processing method of nickel sulfate solution, comprising the following steps:

[0137] The MHP raw material was added to the anolyte and sulfuric acid for leaching to obtain the nickel sulfate solution: Ni 112g / L, Co 21g / L, Mn 21g / L, Cu 0.1g / L, Cr 300mg / L, Fe 2000mg / L, Al 1000mg / L, Si 1000mg / L, Ca 555mg / L, Mg 6.1g / L.

[0138] In the neutralization process, a nickel-based neutralizing agent (nickel precipitation material containing nickel hydroxide) is added to the nickel sulfate solution to adjust the pH value to 5.5, and the process temperature is controlled at about 80°C. After stabilization for a period of time, the solid-liquid separation is carried out to obtain a first solid and a first solution (crude nickel sulfate). The components of the first solution are: Ni 108g / L, Co 20g / L, Mn 21g / L, Cu 0.1g / L, Cr 1mg / L, Fe0.1mg / L, Al 1mg / L, Si 20mg / L, Ca 550mg / L, and Mg 6.0g / L.

[0139] In the pickling process, the first solid is added with a dilute acid solution with a pH value of 1.5 to 2.0 and stirred for a period of time, and then the solid and liquid are separated to obtain a second solid and a second solution. The second solution is returned to the system for use. The second solid components include: Ni 20%, Co 1%, Cu 0.5%, and Fe 6%.

[0140] In the smelting process, the second solid is put into a blowing furnace with sulfur and anthracite at a ratio of 1:0.03:0.08, and oxygen-rich air is introduced. It is smelted at 1600°C to obtain high-grade nickel matte. The components of high-grade nickel matte include: Ni 73%, Co 2%, Cu 3%, Fe 4%, and S18%.

[0141] The extraction and oil removal process includes:

[0142] In the first saponification step, the first extractant P204 and the nickel-precipitated material containing nickel hydroxide are saponified at 65° C. to obtain a first nickel soap organic phase, wherein the nickel content in the first nickel soap organic phase is 12 g / L.

[0143] In the first extraction step, the first solution and the first nickel soap are organically extracted in a volume ratio of 1:3, and the resulting raffinate is the third solution. The third solution contains elements such as nickel, cobalt, and magnesium, and impurities such as manganese, copper, zinc, iron, and calcium are extracted into the organic phase.

[0144] In the first deoiling step, nickel precipitate material containing nickel hydroxide is added to the third solution, and the slurry is stirred to remove oil. The nickel hydroxide adsorbs organic matter. After solid-liquid separation, a third solid (containing adsorbed organic matter) and a fourth solution are obtained. The organic phase content of the fourth solution is 4.6 mg / L.

[0145] In the second saponification step, the second extractant P507 and the nickel-precipitated material containing nickel hydroxide are saponified at 65° C. to obtain a second nickel soap organic phase, and the nickel content of the second nickel soap organic phase is 11.8 g / L.

[0146] In the second extraction step, the fourth solution and the second nickel soap organic phase are extracted according to a volume ratio of 1:4, and elements such as cobalt and magnesium are extracted into the organic phase. The obtained extract residue is the fifth solution. The components of the fifth solution are: Ni 120g / L, Co5mg / L, Mn 0.01mg / L, Cu 0.01mg / L, Cr0.1mg / L, Fe 0.01mg / L, Al 0.1mg / L, Si 20mg / L, Ca0.4mg / L, Mg 1.0mg / L, and oil 50mg / L.

[0147] In the second deoiling step, nickel precipitate material containing nickel hydroxide is added to the fifth solution, and the mixture is stirred to remove oil, and a fourth solid and a sixth solution are obtained after solid-liquid separation. The organic phase content of the sixth solution is 3.0 mg / L.

[0148] In the electrolytic process, the sixth solution is pumped into the electrolytic tank, and after electrolytic deposition, an anolyte and an electrolytic nickel plate are obtained.

[0149] In the nickel precipitation process, liquid alkali is added to the anode liquid to precipitate and obtain a nickel precipitation material containing nickel hydroxide.

[0150] Comparative Example 1

[0151] Comparative Example 1 provides a method for treating a nickel sulfate solution, which differs from Example 1 in that calcium carbonate is used to adjust the pH value in the neutralization process. The first solid obtained in Comparative Example 1 has a high calcium content and cannot be directly used to produce high-grade nickel matte. The Ca content of the first solution is >550 mg / L, which is saturated calcium. In subsequent operations such as liquid transfer, saturated calcium will precipitate and block the pipeline.

[0152] Comparative Example 2

[0153] The difference between Comparative Example 2 and Example 1 is that the first solid adopts a wet treatment method, and Comparative Example 2 is to add water and sulfuric acid to the first solid for secondary leaching, and the slurry after leaching is adjusted to pH 4.0-5.0 by adding alkaline materials, and solid-liquid separation is performed after stabilization for a period of time. The obtained filter residue can be outsourced after two washings; the obtained filtrate is generally returned to the feeding end for slurrying. The difference from Example 1 is that the first solid adopts acid-added secondary leaching, value adjustment and impurity removal, and solid-liquid separation to recover metallic nickel and open-circuit impurities. The treatment process is complicated, and there is a problem of internal circulation of impurities such as Al, and the impurity removal residue is a hazardous waste with high treatment cost.

[0154] Comparative Example 3

[0155] The difference between Comparative Example 3 and Example 1 is that the third solution or the fifth solution is passed through the activated carbon column at a certain flow rate, and the activated carbon is replaced in time according to the oil content of the deoiled liquid, and the replaced activated carbon is outsourced for regeneration or outsourced treatment after washing. The difference from Example 1 is that the use of activated carbon for deoiling has a stable deoiling effect, but the amount of activated carbon used is large (the amount of activated carbon used is: 4-8kg per cubic meter of solution), the loss ratio of the extractant is high (the loss amount of the extractant is: 1-2L per cubic meter of solution), and the used activated carbon is a hazardous solid waste, and its disposal cost is high.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0157] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present application and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. A method for treating a nickel sulfate solution, characterized in that: include: A neutralization step, adding a nickel-based neutralizing agent to the nickel sulfate solution to remove impurities, thereby obtaining a first solution and a first solid; An extraction and degreasing step, wherein the first solution is subjected to nickel soap extraction and degreasing to obtain a degreasing solution; An electrowinning step of electrowinning the degreasing solution to obtain an anolyte and an electrowinning nickel plate; The nickel precipitation process includes adding sodium hydroxide and / or sodium carbonate into the anode liquid to obtain a nickel precipitation material after precipitation; the nickel precipitation material is used as the nickel-based neutralizer.

2. The method for treating a nickel sulfate solution according to claim 1, wherein: Also includes: an acid washing step, washing the first solid with acid and performing solid-liquid separation to obtain a second solution and a second solid; In the smelting process, the second solid is smelted with a sulfiding agent and a reducing agent in an oxygen-containing atmosphere to obtain high-grade nickel matte.

3. The method for treating a nickel sulfate solution according to claim 2, wherein: At least one of the following conditions is met: A. the nickel content of the second solid is 10%-20%; B. The mass ratio of the second solid to the sulfur element in the vulcanizing agent and the reducing agent is 1:(0.03-0.04):(0.08-0.12); C. the vulcanizing agent is sulfur or sulfide; D. The reducing agent is coke powder, bituminous coal or anthracite; E. at least 80 wt% of the reducing agent can pass through an 80-mesh sieve; F. The smelting temperature is 1200°C-1600°C; G. The composition of the high nickel matte includes: Ni 60%-73%, Co 1%-2%, Cu 3%-8%, Fe4-10%, S18%-23%; H. The components of the nickel sulfate solution include Ni 60-120g / L, Co 3-21g / L, Mn 3-21g / L, Cu0.1-3g / L, Cr100-300mg / L, Fe 500-2000mg / L, Al 300-1000mg / L, Si100-1000mg / L, Ca 100-600mg / L, Mg1-6.5g / L.

4. The method for treating a nickel sulfate solution according to claim 1, wherein: The extraction and oil removal process comprises: A first saponification step, saponifying the first extractant and the nickel-precipitated material to obtain a first nickel soap organic phase; A first extraction step, contacting the first solution with the first nickel soap organic phase for extraction to obtain a third solution; In the first deoiling step, the third solution is brought into contact with the nickel-precipitated material to remove the oil, thereby obtaining a fourth solution and a third solid.

5. The method for treating the nickel sulfate solution according to claim 4, characterized in that: Also includes: A second saponification step, saponifying the second extractant and the nickel-precipitated material to obtain a second nickel soap organic phase; a second extraction step, contacting the fourth solution with the second nickel soap organic phase for extraction to obtain a fifth solution; The second deoiling step is to contact the fifth solution with the nickel-precipitated material to remove oil, thereby obtaining a sixth solution and a fourth solid, wherein the sixth solution is the deoiling solution.

6. The method for treating a nickel sulfate solution according to claim 5, characterized in that: The nickel-precipitated material saponified with the first extractant includes the third solid; the nickel-precipitated material saponified with the second extractant includes the fourth solid.

7. The method for treating a nickel sulfate solution according to claim 6, wherein: At least one of the following conditions is met: A. The saponification temperature is 45-65°C; B. the first extractant is selected from P204; C. the second extractant is selected from P507; D. The nickel content in the second nickel soap organic phase and the first nickel soap organic phase is independently 6-12 g / L.

8. The method for treating a nickel sulfate solution according to claim 5, characterized in that: At least one of the following conditions is met: A. the oil content of the fourth solution and the sixth solution is ≤5 mg / L; B. The components of the fifth solution include: Ni 70-120 g / L, Co 5-24 mg / L, Mn 0.01-2 mg / L, Cu 0.01-2 mg / L, Cr ≤ 1 mg / L, Fe 0.01-1 mg / L, Al 0.1-1 mg / L, Si 20-50 mg / L, Ca 0.1-3 mg / L, Mg 1-300 mg / L, and oil 10-50 mg / L.

9. The method for treating a nickel sulfate solution according to claim 1, characterized in that: At least one of the following conditions is met: A. The pH value of the impurity removal process is 4.0-6.0; B. The temperature of the impurity removal process is 65-80°C; C. Dry mass of the nickel-based neutralizer (t): Volume of the nickel sulfate solution (m 3 )=1:60~300; D. The components of the first solution include: Ni 65-110 g / L, Co 3-20 g / L, Mn 3-20 g / L, Cu 0.1-2 g / L, Cr 1-50 mg / L, Fe 0.1-50 mg / L, Al 1-50 mg / L, Si 20-80 mg / L, Ca 100-550 mg / L, Mg 1-6 g / L; E. The first solid includes: nickel hydroxide, iron-silicon-aluminum precipitate and manganese dioxide.

10. The method for treating a nickel sulfate solution according to claim 1, characterized in that: The method for preparing the nickel sulfate solution comprises: adding acid and the anolyte to nickel cobalt hydroxide for leaching.

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