Method for preparing nickel sulfate by leaching high-nickel matte under normal pressure

Abstract

The invention relates to a method for preparing nickel sulfate through normal-pressure leaching of high-nickel matte, and belongs to the technical field of metal separation and enrichment, and the raw materials for preparing the nickel sulfate through normal-pressure leaching of the high-nickel matte comprise a copper sulfate solution, high nickel matte, hydrogen peroxide, an acid treatment agent, cobalt nickel hydroxide, deionized water, sulfuric acid, sodium chlorate, sodium carbonate and nickel carbonate. According to the method for preparing the nickel sulfate through normal-pressure leaching of the high-nickel matte, the problem that high-temperature and high-pressure expensive equipment is used is avoided, the method that copper sulfate and compressed air are matched for one-time leaching is innovatively introduced, and leaching of nickel in the high-nickel matte is increased to the maximum extent; and finally, residual metal in the slag is leached out through sodium chlorate by utilizing a total leaching process, so that the metal recovery rate is increased. Equipment and materials involved in the method are simple, the whole production process is economical, environmentally friendly and wide in applicability, and the production cost is greatly reduced by matching with a semi-extraction process.

Description

Technical Field

[0001] The invention belongs to the technical field of separation and enrichment of metals, and in particular relates to a method for preparing nickel sulfate by leaching high-nickel matte at normal pressure. Background Art

[0002] As an important nickel ore resource, the industrial processing of nickel sulfide ore usually includes multiple steps. First, the nickel sulfide ore is concentrated by beneficiation to obtain nickel concentrate, and then a large amount of gangue, iron and part of sulfur in the nickel concentrate are removed by pyrometallurgy to produce high-nickel matte (commonly known as high-nickel matte). High-nickel matte is then further processed to extract nickel through grinding and flotation-nickel sulfide anode electrolytic refining process or hydrometallurgical process.

[0003] In the grinding-floating-nickel sulfide anode electrolytic refining process, the difference in mutual solubility of each component of the high-matte nickel melt during the slow cooling of the ingot is used to generate nickel sulfide and copper sulfide grains with different chemical compositions, as well as nickel-copper alloy phases. The nickel-copper alloy is selected by magnetic separation, and then the nickel sulfide concentrate and copper sulfide concentrate are separated by flotation. The secondary nickel sulfide concentrate is then cast into an anode for electrolytic treatment to obtain high-purity nickel.

[0004] These methods achieve separation and enrichment of metals by selective leaching in hydrometallurgical processes.

[0005] Traditional hydrometallurgical processes, common methods include sulfuric acid leaching, chloride leaching, pressure leaching and oxygen pressure leaching. Although these traditional processes have certain maturity and effectiveness, there are still many challenges and shortcomings. In particular, the acid leaching method often faces problems such as environmental pollution, economy and processing efficiency. During the acid leaching process, the use of a large amount of acid and other chemicals not only increases the environmental burden, but may also lead to the generation of waste liquid and waste gas, affecting the environmental friendliness of the production process. Economically, the traditional method consumes a large amount of acid, the equipment maintenance cost is high, and the operating cost is high. In terms of processing efficiency, the traditional process has problems such as uneven particle size and imprecise control of reaction conditions, which may affect the leaching effect of the metal.

[0006] Through the improvement, the present invention improves the nickel extraction efficiency, and also shows significant advantages in terms of economy and environmental protection, providing a better solution for the process of atmospheric pressure leaching of high nickel matte. These optimization measures enable the present invention to show higher economic benefits and environmental protection in practical applications, and meet the requirements of modern metallurgical industry for sustainable development. Summary of the invention

[0007] The purpose of the present invention is to provide a method for preparing nickel sulfate by leaching high-nickel matte at normal pressure, in particular, by controlling the compressed air flux, the proportion of copper sulfate, the amount of oxidant and the reducing agent in the leaching process, and coordinating the semi-extraction process and the full leaching process, not only the nickel leaching rate is increased, but also the overall recovery rate of the metal is improved.

[0008] The specific technical solutions are as follows:

[0009] 1. A method for preparing nickel sulfate by leaching high nickel matte at normal pressure. The raw materials of the method for preparing nickel sulfate by leaching high nickel matte at normal pressure are composed of 60 to 80 parts of copper sulfate solution, 28,000 to 30,000 parts of high nickel matte, 6,000 to 7,000 parts of hydrogen peroxide, 2,500 to 3,000 parts of acid treatment agent, 500 to 1,000 parts of nickel cobalt hydroxide, 18,000 to 20,000 parts of deionized water, 300 to 500 parts of sodium chlorate, 50 to 1,000 parts of sodium carbonate, and 50 to 1,000 parts of nickel carbonate. The specific steps of preparing nickel sulfate by leaching high nickel matte at normal pressure are as follows:

[0010] S1: Add acid treatment agent and high nickel matte in proportion to the multifunctional reactor, stir at a rate of 1300-1500r / min, mix and stir at 10-30℃ for 30-120 minutes; after stirring, pass it into the primary leaching tank and introduce compressed air with an air flow rate of about 1000-1500m 3 / h, throughout the entire leaching process, about 8 to 12 hours, add copper sulfate solution in proportion to mix and stir, and perform one leaching;

[0011] S2: When the total amount of metal in the primary leaching solution in step S1 is greater than 75%, filter pressing is performed with a filtration area of ​​100 to 120 m 2 The filtration pressure is 0.4-0.8MPa, and primary leaching liquid and primary leaching residue are obtained. The obtained filtrate is transferred to the iron removal tank;

[0012] S3: adding the primary leaching residue into the secondary leaching tank, adding hydrogen peroxide and acid treatment agent in proportion, controlling the pH value to be less than 0.5, and performing secondary pressure filtration at a filtration pressure of 0.4-0.8 MPa to obtain secondary leaching solution and secondary leaching residue;

[0013] S4: transferring the secondary leaching residue obtained by filter pressing in step S3 into a tertiary leaching tank, adding sodium chlorate in proportion to perform leaching and filter pressing, the filtration pressure is 0.4-0.8 MPa, and obtaining a tertiary leaching liquid and tertiary leaching residue;

[0014] S5: extracting copper from the secondary leaching solution in step S3 to remove copper;

[0015] S6: The primary leaching solution in step S2 and the secondary leaching solution from which copper is removed in step S5 are mixed in a multifunctional reactor, nickel and cobalt hydroxide are added in proportion, iron and aluminum in the solution are removed, and pressure filtration is performed at a filtration pressure of 0.4 to 0.8 MPa to obtain a solution 1 after iron removal;

[0016] S7: Add the tertiary leaching solution in step S4 into a multifunctional reactor, add sodium carbonate and nickel carbonate in proportion, remove iron and aluminum in the solution, and perform pressure filtration at a filtration pressure of 0.4 to 0.8 MPa to obtain a deironized solution 2;

[0017] S8: Mix the iron-removed liquid 1 in step S7 and the iron-removed liquid 2 in step S8, remove zinc and manganese through a P204 impurity extraction line, remove cobalt through a P507 cobalt extraction line, remove magnesium through a P507 impurity extraction line, and obtain a nickel sulfate mixed solution through a P507 nickel extraction line;

[0018] S9: Nickel sulfate solution is concentrated to 1.6-1.7 g / cm 3 , transfer to the crystallization kettle and stir at 50-70r / min, cool to 53-58℃ with cooling water, add 50-80kg / m 3 The crystal seeds are grown naturally for 8 to 12 hours, and then naturally cooled to 45 to 50° C., and then spun, dried, sieved and packaged to obtain a nickel sulfate crystal product.

[0019] In some embodiments, the acid treatment agent in step S3 can be a combination of one or more of sulfuric acid and hydrochloric acid.

[0020] In some embodiments, at the beginning of the secondary leaching in step S3, a first portion of hydrogen peroxide is added, the amount of which is 30-40% of the total amount of hydrogen peroxide required; after the reaction is carried out for 30-60 minutes, a second portion of hydrogen peroxide is added, the amount of which is 20-30% of the total amount of hydrogen peroxide required; and in the last 30-60 minutes of the reaction, a final portion of hydrogen peroxide is added, the amount of which is 30-40% of the total amount of hydrogen peroxide required.

[0021] In some embodiments, before the primary leaching residue is transferred into the secondary leaching tank in step S3, the primary leaching residue needs to be dried at 60-100° C. for 4-6 hours and crushed into 0.1-5 mm slag, and the slag is mixed and stirred at a stirring rate of 1300-1500 r / min for 30-120 minutes to ensure that the slag is evenly mixed before entering the secondary leaching tank to ensure that the leachate can fully penetrate each part of the slag.

[0022] In some of the embodiments, when the pressure difference increases by more than 0.2-0.5 MPa during the filter press operation, a high-pressure water gun is used to clean the filter cloth to prevent the filter cloth from being blocked and causing a decrease in filtration efficiency.

[0023] In some of the embodiments, the nickel matte in step S1 needs to be crushed before being added, and is crushed into a particle size of 0.074 to 0.5 mm using a ball mill.

[0024] This reaction has the following advantages:

[0025] (1) Yield improvement: The output of nickel sulfate can be increased by crushing, controlling the compressed air flux, copper sulfate ratio, oxidant and reductant dosage during the leaching process;

[0026] (2) Production cost: The semi-extraction process can reduce the production cost of the extraction process;

[0027] (3) Waste recycling: In the production process, multiple production lines are adopted to achieve the classified recycling of different metals through different extraction agents. DETAILED DESCRIPTION

[0028] The following will combine the technical process steps, specific implementation conditions and materials in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] Use a ball mill to crush the high-matte nickel to a particle fineness of 0.2mm. Add sulfuric acid and high-matte nickel in proportion to a multifunctional reactor, stir at a rate of 1300r / min, and mix and stir for 30 minutes at 10-30°C; after stirring, pass it into a primary leaching tank, and pass compressed air with an air flow rate of about 5L / min, add copper sulfate solution in proportion for mixing and stirring, and perform a primary leaching. When the total amount of metal in the primary leaching solution is greater than 75%, perform filter pressing with a filtration pressure of 0.5MPa to obtain a primary leaching solution and a primary leaching slag. After drying the primary leaching slag at 70°C for 4 hours, crush it into a slag of 0.1mm, mix and stir the slag at a stirring rate of 1300r / min for 30 minutes to obtain the treated primary leaching slag for standby use.

[0031] Table 1 Example 1 Raw material ratio required for primary leaching of high-grade nickel matte

[0032] sulfuric acid 2600 copies High nickel matte 28,000 copies Copper sulfate solution 65 servings

[0033] Example 2

[0034] Use a ball mill to crush the high-matte nickel to a particle size of 0.4mm. Add sulfuric acid and high-matte nickel in proportion to a multifunctional reactor, stir at a rate of 1400r / min, and mix and stir for 100 minutes at 20°C; after stirring, pass it into a primary leaching tank, and pass compressed air with an air flow rate of about 8L / min, add copper sulfate solution in proportion for mixing and stirring, and perform a primary leaching. When the total amount of metal in the primary leaching solution is greater than 75%, perform filter pressing with a filtration pressure of 0.8MPa to obtain a primary leaching solution and a primary leaching slag. After drying the primary leaching slag at 90°C for 5 hours, crush it into 3mm slag, mix and stir the slag at a stirring rate of 1500r / min for 120 minutes to obtain the treated primary leaching slag for standby use.

[0035] Table 2 Example 2 Raw material ratio required for primary leaching of high nickel matte

[0036] sulfuric acid 2800 copies High nickel matte 29,000 copies Copper sulfate solution 75 servings

[0037] Example 3

[0038] The primary leaching residue obtained in Example 1 is added to the secondary leaching tank, and 3% hydrogen peroxide and 1% acid are added in proportion for secondary pressure filtration, and the filtration pressure is 0.5MPa. At the beginning of the secondary leaching, the first part of hydrogen peroxide is added, and the amount is 30% of the total amount of hydrogen peroxide required. After the reaction is carried out for 30 minutes, the second part of hydrogen peroxide is added, and the amount is 20% of the total amount of hydrogen peroxide required. In the last 30 minutes of the reaction, the last part of hydrogen peroxide is added, and the amount is 30% of the total amount of hydrogen peroxide required. A secondary leaching solution and secondary leaching residue are obtained, and the secondary leaching solution is subjected to copper extraction to obtain a secondary leaching solution with copper removed, which is reserved for use.

[0039] Table 3 Example 3 Raw material ratio required for secondary leaching of high nickel matte

[0040] Primary leaching residue 18200 copies Hydrogen Peroxide 6000 copies sulfuric acid 2500 copies

[0041] Example 4

[0042] The primary leaching residue obtained in Example 2 is added to the secondary leaching tank, and 5% hydrogen peroxide and 5% acid are added in proportion for secondary pressure filtration, and the filtration pressure is 0.8MPa. At the beginning of the secondary leaching, the first part of hydrogen peroxide is added, and the amount is 40% of the total amount of hydrogen peroxide required. After the reaction is carried out for 60 minutes, the second part of hydrogen peroxide is added, and the amount is 30% of the total amount of hydrogen peroxide required. In the last 60 minutes of the reaction, the last part of hydrogen peroxide is added, and the amount is 40% of the total amount of hydrogen peroxide required. A secondary leaching solution and secondary leaching residue are obtained, and the secondary leaching solution is subjected to copper extraction to obtain a secondary leaching solution with copper removed, which is reserved for use.

[0043] Table 4 Example 4 Raw material ratio required for secondary leaching of high nickel matte

[0044]

[0045]

[0046] Example 5

[0047] The secondary leaching residue obtained by filter pressing in Example 3 was transferred to a tertiary leaching tank, and 400 parts of sodium chlorate were added in proportion for leaching and filter pressing. The filtration pressure was 0.5 MPa, and tertiary leaching liquid and tertiary leaching residue were obtained for standby use.

[0048] Example 6

[0049] The secondary leaching residue obtained by filter pressing in Example 4 was transferred to a tertiary leaching tank, and 500 parts of sodium chlorate were added in proportion for leaching and filter pressing. The filtration pressure was 0.8 MPa, and tertiary leaching liquid and tertiary leaching residue were obtained for standby use.

[0050] Example 7

[0051] The primary leaching solution in Example 1 and the secondary leaching solution from which copper is removed in Example 3 are mixed in a multifunctional reactor, 500 parts of nickel cobalt hydroxide are added, iron and aluminum in the solution are removed, and pressure filtration is performed at a filtration pressure of 0.5 MPa to obtain a solution 1 after iron removal;

[0052] Example 8

[0053] The primary leaching solution in Example 2 and the secondary leaching solution from which copper is removed in Example 4 are mixed in a multifunctional reactor, 800 parts of nickel cobalt hydroxide are added, iron and aluminum in the solution are removed, and pressure filtration is performed at a filtration pressure of 0.8 MPa to obtain a solution 1 after iron removal;

[0054] Example 9

[0055] The tertiary leaching solution in Example 5 was added into a multifunctional reactor, and 50 parts of sodium carbonate and 60 parts of nickel carbonate were added in proportion to remove iron and aluminum in the solution, and filter press was performed at a filtration pressure of 0.5 MPa to obtain a deironized solution 2;

[0056] Example 10

[0057] The tertiary leaching solution in Example 6 was added into a multifunctional reactor, and 120 parts of sodium carbonate and 170 parts of nickel carbonate were added in proportion to remove iron and aluminum in the solution, and filter press was performed at a filtration pressure of 0.8 MPa to obtain a deironized solution 2;

[0058] Embodiment 11

[0059] The iron-removed liquid 1 in Example 7 and the iron-removed liquid 2 in Example 9 were mixed, zinc and manganese were removed by P204 impurity extraction line, cobalt was removed by P507 cobalt extraction line, magnesium was removed by P507 impurity extraction line, and nickel sulfate mixed solution was obtained by P507 nickel extraction line; the nickel sulfate solution was concentrated to 1.6 g / cm 3 , transfer to the crystallization kettle and stir at 50r / min, cool to 53℃ with cooling water, add 50kg / m 3 The crystal seeds are grown naturally for 8 hours, cooled naturally to 45°C, and then spun, dried, sieved and packaged to obtain a nickel sulfate crystal product.

[0061] According to "HG / T 2824-2009 Industrial Nickel Sulfate", the weight method and complexometric titration method were used to determine the content of different components in the prepared nickel sulfate. The test results showed that it met the national standards.

[0062] Table 1 Detection composition table of nickel sulfate crystal product prepared in Example 11

[0063] project content Nickel(Ni)w% 93.7 Cobalt (Co) w% 0.0029 Copper (Cu) w% 0.0004 Iron (Fe) w% 0.0007 Manganese (Mn) w% 0.0017 Zinc (Zn) w% 0.0008 Calcium (Ca) w% 0.004 Magnesium (Mg) w% 0.0001 Cadmium(Cd)w% 0.0004 Chromium (Cr) w% 0.0002 Lead (Pb) w% 0.0001 Sodium(Na)w% 0.027 Mercury (Hg) w% 0.0005 Water insoluble matter w% 0.004

[0064] Example 12

[0065] The iron-removed liquid 1 in Example 8 and the iron-removed liquid 2 in Example 10 were mixed, and zinc and manganese were removed by a P204 impurity extraction line, cobalt was removed by a P507 cobalt extraction line, magnesium was removed by a P507 impurity extraction line, and a nickel sulfate mixed solution was obtained by a P507 nickel extraction line; the nickel sulfate solution was concentrated to 1.7 g / cm 3 , transfer to the crystallization kettle and stir at 70r / min, cool to 58℃ with cooling water, add 80kg / m 3 The crystal seeds are grown naturally for 12 hours, cooled naturally to 50°C, and then spun, dried, sieved and packaged to obtain nickel sulfate crystal products.

[0066] According to "HG / T 2824-2009 Industrial Nickel Sulfate", the weight method and complexometric titration method were used to determine the content of different components in the prepared nickel sulfate. The test results showed that it met the national standards.

[0067] Table 1 Detection composition table of nickel sulfate crystal product prepared in Example 11

[0068]

[0069]

[0070] Technical personnel should note that: Although the present invention has been described according to the above specific implementation methods, the inventive concept of the present invention is not limited to this invention, and any modification using the inventive concept will be included in the scope of protection of this patent.

Claims

1. A method for preparing nickel sulfate by leaching high-nickel matte at normal pressure, characterized in that: The raw material composition of the method for preparing nickel sulfate by leaching high nickel matte at normal pressure is as follows: 60-80 parts of copper sulfate solution, 28000-30000 parts of high nickel matte, 6000-7000 parts of hydrogen peroxide, 2500-3000 parts of acid treatment agent, 500-1000 parts of nickel cobalt hydroxide, 18000-20000 parts of deionized water, 300-500 parts of sodium chlorate, 50-1000 parts of sodium carbonate, 50-1000 parts of nickel carbonate. The specific steps of preparing nickel sulfate by leaching high nickel matte at normal pressure are as follows: S1: Add acid treatment agent and high nickel matte in proportion to the multifunctional reactor, stir at a rate of 1300-1500r / min, mix and stir at 10-30℃ for 30-120 minutes; after stirring, pass it into the primary leaching tank and introduce compressed air with an air flow rate of about 1000-1500m 3 / h, throughout the entire leaching process, about 8 to 12 hours, add copper sulfate solution in proportion to mix and stir, and perform one leaching; S2: When the total amount of metal in the primary leaching solution in step S1 is greater than 75%, filter pressing is performed with a filtration area of ​​100 to 120 m 2 The filtration pressure is 0.4-0.8MPa, and primary leaching liquid and primary leaching residue are obtained. The obtained filtrate is transferred to the iron removal tank; S3: adding the primary leaching residue into the secondary leaching tank, adding hydrogen peroxide and acid treatment agent in proportion, controlling the pH value to be less than 0.5, and performing secondary pressure filtration at a filtration pressure of 0.4-0.8 MPa to obtain secondary leaching solution and secondary leaching residue; S4: transferring the secondary leaching residue obtained by filter pressing in step S3 into a tertiary leaching tank, adding sodium chlorate in proportion to perform leaching and filter pressing, the filtration pressure is 0.4-0.8 MPa, and obtaining a tertiary leaching liquid and tertiary leaching residue; S5: extracting copper from the secondary leaching solution in step S3 to remove copper; S6: The primary leaching solution in step S2 and the secondary leaching solution from which copper is removed in step S5 are mixed in a multifunctional reactor, nickel and cobalt hydroxide are added in proportion, iron and aluminum in the solution are removed, and pressure filtration is performed at a filtration pressure of 0.4 to 0.8 MPa to obtain a solution 1 after iron removal; S7: Add the tertiary leaching solution in step S4 into a multifunctional reactor, add sodium carbonate and nickel carbonate in proportion, remove iron and aluminum in the solution, and perform pressure filtration at a filtration pressure of 0.4 to 0.8 MPa to obtain a deironized solution 2; S8: Mix the iron-removed liquid 1 in step S7 and the iron-removed liquid 2 in step S8, remove zinc and manganese through a P204 impurity extraction line, remove cobalt through a P507 cobalt extraction line, remove magnesium through a P507 impurity extraction line, and obtain a nickel sulfate mixed solution through a P507 nickel extraction line; S9: Nickel sulfate solution is concentrated to 1.6-1.7 g / cm 3 , transfer to the crystallization kettle and stir at 50-70r / min, cool to 53-58℃ with cooling water, add 50-80kg / m 3 The crystal seeds are grown naturally for 8 to 12 hours, and then naturally cooled to 45 to 50° C., and then spun, dried, sieved and packaged to obtain a nickel sulfate crystal product.

2. The method for preparing nickel sulfate by leaching high nickel matte at normal pressure as claimed in claim 1, characterized in that: The acid treatment agent in step S3 can be a combination of one or more of sulfuric acid and hydrochloric acid.

3. The method for preparing nickel sulfate by leaching high-nickel matte at normal pressure as claimed in claim 1, characterized in that: At the beginning of the secondary leaching in step S3, a first portion of hydrogen peroxide is added, the amount of which is 30-40% of the total amount of hydrogen peroxide required; after the reaction is carried out for 30-60 minutes, a second portion of hydrogen peroxide is added, the amount of which is 20-30% of the total amount of hydrogen peroxide required; and in the last 30-60 minutes of the reaction, a final portion of hydrogen peroxide is added, the amount of which is 30-40% of the total amount of hydrogen peroxide required.

4. The method for preparing nickel sulfate by leaching high nickel matte at normal pressure as claimed in claim 1, characterized in that: Step S3: Before the primary leaching residue is transferred to the secondary leaching tank, the primary leaching residue needs to be dried at 60-100° C. for 4-6 hours and crushed into 0.1-5 mm slag. The slag is mixed and stirred at a stirring rate of 1300-1500 r / min for 30-120 minutes to ensure that the slag is evenly mixed before entering the secondary leaching tank to ensure that the leachate can fully penetrate each part of the slag.

5. The method for preparing nickel sulfate by leaching high nickel matte at normal pressure as claimed in claim 1, characterized in that: When performing filter press operation, when the pressure difference increases by more than 0.2-0.5MPa, use a high-pressure water gun to clean the filter cloth to prevent clogging of the filter cloth and reduce the filtration efficiency.

6. The method for preparing nickel sulfate by leaching high nickel matte at normal pressure as claimed in claim 1, characterized in that: The high nickel matte in step S1 needs to be crushed before being added, and is crushed into a particle size of 0.074 to 0.5 mm using a ball mill.

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