METHOD FOR PRODUCING BATTERY-GRADE NICKEL SULFATE BY USING LATERITE NICKEL ORE

Abstract

Disclosed is a method for producing battery-grade nickel sulfate by using laterite nickel ore comprising the following steps: sorting the laterite nickel ore to obtain lump ore and sediment ore; crushing the lump ore, and then performing heap leaching, to obtain a crude nickel sulfate solution A; separating the sediment ore to obtain high chromium ore, low iron, high magnesium ore, and high iron, low magnesium ore, and drying, roasting, reducing, and sulfurating the low iron, high magnesium ore to obtain low nickel matte; blowing and performing water extraction on the low nickel matte, and then performing oxygen pressure leaching, to obtain a crude nickel sulfate solution B; performing pressure leaching on the high iron, low magnesium ore to obtain a crude nickel sulfate solution C; and performing extraction on the crude nickel sulfate solutions A, B, and C, and then evaporating and crystallizing, to obtain battery-grade nickel sulfate.

Claims

1. A method for producing battery-grade nickel sulfate by using laterite nickel ore, comprising the following steps: (1) sorting the laterite nickel ore to obtain lump ore and sediment ore; wherein the lump ore and the sediment ore are sorted according to a particle size, where a particle size of the lump ore is greater than 10 mm, and a particle size of the sediment ore is less than 10 mm (2) crushing the lump ore, and then performing heap leaching, to obtain a crude nickel sulfate solution A; (3) separating the sediment ore to obtain high chromium ore, low iron, high magnesium ore, and high iron, low magnesium ore, and drying, roasting, reducing, and sulfurating the low iron, high magnesium ore to obtain low nickel matte; wherein the high chromium ore comprises 30-40% of chromium and 0.1-0.2% of nickel; the low iron, high magnesium ore is mainly garnierite and comprisesl.5-2.1% of nickel, 15-25% of magnesium, 8-25% of iron, and 35-50% of silicon; and the high iron, low magnesium ore is mainly limonite and comprises 0.8-1.3% of nickel, 30-50% of iron, 0.1-10% of magnesium, and 10-30% of silicon; (4) blowing and performing water extraction on the low nickel matte, and then performing oxygen pressure leaching, to obtain a crude nickel sulfate solution B; (5) performing pressure leaching on the high iron, low magnesium ore to obtain a crude nickel sulfate solution C; and (6) performing extraction on the crude nickel sulfate solution A, the crude nickel sulfate solution B, and the crude nickel sulfate solution C, and then evaporating and crystallizing, to obtain battery-grade nickel sulfate; wherein, in the battery-grade nickel sulfate, a content of Mg<0.002%, a content of Si<0.001%, a content of magnetic substance<0.08%, and a content of Co<0.002%.

2. The method according to claim 1, wherein in step (1), the laterite nickel ore mainly comprises the following components by mass percentage: 1.2-2% of Ni, 15-40% of Fe, 6-20% of Mg, 0.03-0.25% of Co, and 10-40% of Si.

3. The method according to claim 1, wherein in step (2), a specific operation of the heap leaching comprises: putting the crushed lump ore into a heap leaching pool, and then leaching nickel from the ore in a manner of spraying and soaking in sulfuric acid, to obtain the crude nickel sulfate solution; and in step (2), for the heap leaching, a temperature is 40-60° C., and a time is 30-50 days.

4. (canceled)

5. The method according to claim 1, wherein in step (3), for the roasting, a temperature is 800-1000° C., and a time is 1-3 h; and in step (3), for the reducing, a temperature is 1400-1600° C., and a time is 2-4 h.

6. The method according to claim 1, wherein in step (3), a reducing agent used for the reducing is at least one of coke, semi-coke, or anthracite.

7. The method according to claim 1, wherein in step (3), for the sulfurating, a temperature is 1100-1400° C., and a time is 0.5-3 h; in step (4), for the oxygen pressure leaching, a temperature is 100-250° C., and a pressure is 1-5 MPa; and in step (5), for the pressure leaching, a temperature is 170-260° C., and a pressure is 1-5 MPa.

8. The method according to claim 1, wherein in step (6), an acidic extractant is used in the extraction, Fe.sup.2+, Mn.sup.2+, Co.sup.2+, Mg.sup.2+, and Ca.sup.3+ are extracted to obtain a nickel sulfate solution, and the acidic extractant is at least one of diisooctyl phosphate, mono 2-ethylhexyl 2-ethylhexyl phosphate, or di(2,4,4-trimethylpentyl).

9. The method according to claim 8, wherein in step (6), a specific operation of the extraction comprises: under conditions of a temperature of 50-80° C. and a pH value of 2-5, first extracting Fe.sup.3+and Mn.sup.2+ by using diisooctyl phosphate, and then extracting Co.sup.2+, Mg.sup.2+, and Ca.sup.2+ by using either or both of mono 2-ethylhexyl 2-ethylhexyl phosphate and di(2,4,4-trimethylpentyl), to obtain the nickel sulfate solution.

10. A method for separating and purifying of nickel ore, comprising using the method according to claim 1.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0051] FIG. 1 is a schematic diagram of a process flow of producing battery-grade nickel sulfate by using laterite nickel ore according to Example 1.

DETAILED DESCRIPTION

[0052] To make a person skilled in the art understand the technical solutions of the present disclosure more clearly, the following examples are listed for description. It should be noted that the following examples do not limit the protection scope of the present disclosure.

[0053] Unless otherwise specified, the raw materials, reagents, or devices used in the following examples can be commercially available, or can be obtained by existing known methods.

Example 1

[0054] A method for producing battery-grade nickel sulfate by using laterite nickel ore was provided, including the following steps:

[0055] (1) The laterite nickel ore mainly containing 1.75% of Ni, 18% of Fe, 15% of Mg, 0.03% of Co, and 30% of Si was crushed by a jaw crusher, and then an impact crusher matching with a vibrating screen, to obtain lump ore having a particle size of greater than 10 mm and sediment ore having a particle size of less than 10 mm.

[0056] (2) The lump ore was crushed to 1-8 mm, piled into a heap leaching pool to be sprayed with a dilute sulfuric acid aqueous solution having a mass concentration of 2%, and leached at a temperature of 50° C. for 40 days, to obtain a crude nickel sulfate solution A.

[0057] (3) The sediment ore was separated to obtain high chromium ore, low iron, high magnesium ore of 0.15-1 mm, and high iron, low magnesium ore of 0.045-0.15 mm, and the low iron, high magnesium ore was dried to a water content of 20-24%, first roasted at 900° C., then reduced (coke and semi coke were added for reduction) at 1500° C., and finally sulfurated at 1200° C. for 1.5 h, to obtain low nickel matte having a nickel content of 18%.

[0058] (4) The low nickel matte was blown into high nickel matte having a nickel content of 70%, the high nickel matte was subjected to water-extraction to obtain nickel beans, and then the nickel beans was subjected to oxygen pressure leaching at 150° C. and 2.5 MPa, to obtain a crude nickel sulfate solution B.

[0059] (5) The high iron, low magnesium ore was subjected to high pressure leaching at 200° C. and 2.5 MPa, to obtain a crude nickel sulfate solution C.

[0060] (6) Under conditions of a temperature of 60° C. and a pH value of 4, from the crude nickel sulfate solution A, the crude nickel sulfate solution B, and the crude nickel sulfate solution C, Fe.sup.3+ and Mn.sup.2+ were extracted by using P204 (diisooctyl phosphate), and then Co.sup.2+, Mg.sup.2+, and Ca.sup.2+ were extracted by using P507 (mono2-ethylhexyl 2-ethylhexyl phosphate) and C272 (di(2,4,4-trimethylpentyl)), to obtain a pure nickel sulfate solution, and then the nickel sulfate solution was evaporated and crystallized to obtain battery-grade nickel sulfate. Contents of impurities in the nickel sulfate product in Example 1 were: cobalt (Co)=0.0003%, iron (Fe)=0.0002%, magnesium (Mg)=0.0001%, manganese (Mn)=0.0001%, and zinc (Zn)=0.0002%. A comprehensive recovery rate of nickel ore was 92% (nickel recovery rate=nickel content of product/nickel content of ore*100%), and smelting costs of nickel sulfate were 10000 US dollars/ton base nickel.

Example 2

[0061] A method for producing battery-grade nickel sulfate by using laterite nickel ore was provided, including the following steps:

[0062] (1) The laterite nickel ore mainly containing 1.2% of Ni, 40% of Fe, 6% of Mg, 0.2% of Co, and 25% of Si was crushed by a jaw crusher, and then an impact crusher matching with a vibrating screen, to obtain lump ore having a particle size of greater than 10 mm and sediment ore having a particle size of less than 10 mm.

[0063] (2) The lump ore was crushed to 1-8 mm, piled into a heap leaching pool to be sprayed with a dilute sulfuric acid aqueous solution having a mass concentration of 2%, and leached at a temperature of 50° C. for 40 days, to obtain a crude nickel sulfate solution A.

[0064] (3) The sediment ore was separated to obtain high chromium ore, low iron, high magnesium ore of 0.15-1 mm, and high iron, low magnesium ore of 0.045-0.15 mm, and the low iron, high magnesium ore was dried to a water content of 20-24%, first roasted at 900° C., then reduced at 1500° C., and finally sulfurated at 1200° C. for 1.5 h, to obtain low nickel matte having a nickel content of 15%.

[0065] (4) The low nickel matte was blown and subjected to water extraction, and then subjected to oxygen pressure leaching at 150° C. and 2.5 MPa, to obtain a crude nickel sulfate solution B.

[0066] (5) The high iron, low magnesium ore was subjected to high pressure leaching at 200° C. and 2.5 MPa, to obtain a crude nickel sulfate solution C.

[0067] (6) Under conditions of a temperature of 60° C. and a pH value of 4, from the crude nickel sulfate solution A, the crude nickel sulfate solution B, and the crude nickel sulfate solution C, Fe.sup.3+ and Mn.sup.3+ were extracted by using P204 (diisooctyl phosphate), and then Co.sup.2+, Mg.sup.2+, and Ca.sup.3+ were extracted by using P507 (mono2-ethylhexyl 2-ethylhexyl phosphate) and C272 (di(2,4,4-trimethylpentyl)), to obtain a pure nickel sulfate solution, and then the nickel sulfate solution was evaporated and crystallized to obtain battery-grade nickel sulfate.

[0068] Contents of impurities in the nickel sulfate product in Example 2 were: cobalt (Co)=0.0005%, iron (Fe)=0.0006%, magnesium (Mg)=0.0001%, manganese (Mn)=0.0002%, and zinc (Zn)=0.0002%. A comprehensive recovery rate of nickel ore was 94%, and smelting costs of nickel sulfate were 10500 US dollars/ton base nickel.

Example 3

[0069] A method for producing battery-grade nickel sulfate by using laterite nickel ore was provided, including the following steps:

[0070] (1) The laterite nickel ore mainly containing 2.0% of Ni, 18% of Fe, 15% of Mg, 0.05% of Co, and 35% of Si was crushed by a jaw crusher, and then an impact crusher matching with a vibrating screen, to obtain lump ore having a particle size of greater than 10 mm and sediment ore having a particle size of less than 10 mm

[0071] (2) The lump ore was crushed to 1-8 mm, piled into a heap leaching pool to be sprayed with a dilute sulfuric acid aqueous solution having a mass concentration of 2%, and leached at a temperature of 50° C. for 40 days, to obtain a crude nickel sulfate solution A.

[0072] (3) The sediment ore was separated to obtain high chromium ore, low iron, high magnesium ore of 0.15-1 mm, and high iron, low magnesium ore of 0.045-0.15 mm, and the low iron, high magnesium ore was dried to a water content of 20-24%, first roasted at 900° C., then reduced at 1500° C., and finally sulfurated at 1200° C. for 1.5 h, to obtain low nickel matte having a nickel content of 28%.

[0073] (4) The low nickel matte was blown and subjected to water extraction, and then subjected to oxygen pressure leaching at 150° C. and 2.5 MPa, to obtain a crude nickel sulfate solution B.

[0074] (5) The high iron, low magnesium ore was subjected to high pressure leaching at 200° C. and 2.5 MPa, to obtain a crude nickel sulfate solution C.

[0075] (6) Under conditions of a temperature of 60° C. and a pH value of 4, from the crude nickel sulfate solution A, the crude nickel sulfate solution B, and the crude nickel sulfate solution C, Fe.sup.3+ and Mn.sup.2+ were extracted by using P204 (diisooctyl phosphate), and then Co.sup.2+, Mg.sup.2+, and Ca.sup.3+ were extracted by using P507 (mono2-ethylhexyl 2-ethylhexyl phosphate) and C272 (di(2,4,4-trimethylpentyl)), to obtain a pure nickel sulfate solution, and then the nickel sulfate solution was evaporated and crystallized to obtain battery-grade nickel sulfate.

[0076] Contents of impurities in the nickel sulfate product in Example 3 were: cobalt (Co)=0.0003%, iron (Fe)=0.0004%, magnesium (Mg)=0.0006%, manganese (Mn)=0.0002%, and zinc (Zn)=0.0001%. A comprehensive recovery rate of nickel ore was 94%, and smelting costs of nickel sulfate were 9850 US dollars/ton base nickel.

Comparative Example 1

[0077] A method for producing battery-grade nickel sulfate by using laterite nickel ore was provided, including the following steps:

[0078] (1) The laterite nickel ore mainly containing 1.75% of Ni, 18% of Fe, 15% of Mg, 0.03% of Co, and 30% of Si was crushed by a jaw crusher, and then an impact crusher matching with a vibrating screen, to obtain lump ore of greater than 10 mm and sediment ore of less than 10 mm.

[0079] (2) The lump ore was crushed, piled into a heap leaching pool to be sprayed with a dilute sulfuric acid aqueous solution having a mass concentration of 2%, and leached at a temperature of 50° C. for 40 days, to obtain a crude nickel sulfate solution.

[0080] (3) The sediment ore was subjected to oxygen pressure leaching at 150° C. and 2.5 MPa, to obtain a crude nickel sulfate solution.

[0081] (4) Under conditions of a temperature of 60° C. and a pH value of 4, from the crude nickel sulfate solutions in steps (2) and (3), Fe.sup.3+ and Mn.sup.3+ were extracted by using P204 (diisooctyl phosphate), and then Co.sup.2+, Mg.sup.2+, and Ca.sup.3+ were extracted by using P507 (mono2-ethylhexyl 2-ethylhexyl phosphate) and C272 (di(2,4,4-trimethylpentyl)), to obtain a pure nickel sulfate solution, and then the nickel sulfate solution was evaporated and crystallized to obtain battery-grade nickel sulfate.

[0082] Contents of impurities in the nickel sulfate product in Comparative example 1 were: cobalt (Co)=0.0003%, iron (Fe)=0.0004%, magnesium (Mg)=0.0006%, manganese (Mn)=0.0002%, and zinc (Zn)=0.0001%. A comprehensive recovery rate of nickel ore was 90%, and smelting costs of nickel sulfate were 12500 US dollars/ton base nickel.

[0083] Example 1 differed from Comparative Example 1 in that, in Comparative Example 1, low iron, high magnesium ore of 0.15-1 mm was not separated from the sediment ore, and all the sediment ore was treated with pressure leaching. Consequently, a large amount of magnesium reacted with acid, and the acid consumption may reach 70 t/t-Ni. The smelting wastewater contained a large amount of Mg ions, resulting in high costs of treatment on wastewater and environmental pollution.

Comparative Example 2

[0084] A method for producing battery-grade nickel sulfate by using laterite nickel ore was provided, including the following steps:

[0085] (1) The laterite nickel ore mainly containing 1.2% of Ni, 40% of Fe, 6% of Mg, 0.2% of Co, and 25% of Si was crushed by a jaw crusher, and then an impact crusher matching with a vibrating screen, to obtain lump ore of greater than 10 mm and sediment ore of less than 10 mm.

[0086] (2) The lump ore was crushed, piled into a heap leaching pool to be sprayed with a dilute sulfuric acid aqueous solution having a mass concentration of 2%, and leached at a temperature of 50° C. for 40 days, to obtain a crude nickel sulfate solution.

[0087] (3) The sediment ore was dried to a water content of 20-24%, first roasted at 900° C., then reduced at 1500° C., and finally sulfurated at 1200° C. for 1.5 h, to obtain low nickel matte having a nickel content of 10%.

[0088] (4) The low nickel matte was blown and subjected to water extraction, and then was subjected to oxygen pressure leaching at 150° C. and 2.5 MPa, to obtain a crude nickel sulfate solution.

[0089] (5) Under conditions of a temperature of 60° C. and a pH value of 4, from the crude nickel sulfate solutions in steps (2) and (4), Fe.sup.3+ and Mn.sup.3+ were extracted by using P204 (diisooctyl phosphate), and then Co.sup.2+, Mg.sup.2+, and Ca.sup.3+ were extracted by using P507 (mono2-ethylhexyl 2-ethylhexyl phosphate) and C272 (di(2,4,4-trimethylpentyl)), to obtain a pure nickel sulfate solution, and then the nickel sulfate solution was evaporated and crystallized to obtain battery-grade nickel sulfate.

[0090] Contents of impurities in the nickel sulfate product in Comparative example 2 were: cobalt (Co)=0.0005%, iron (Fe)=0.0006%, magnesium (Mg)=0.0001%, manganese (Mn)=0.0002%, and zinc (Zn)=0.0002%. A comprehensive recovery rate of nickel ore was 87%, and smelting costs of nickel sulfate were 11500 US dollars/ton base nickel.

[0091] Example 2 differed from Comparative Example 2 in that, in Comparative Example 2, high iron, low magnesium ore of 0.045-0.15 mm was not separated, and instead, all sediment ore entered an RKEF production line for producing ferronickel, resulting a high iron content of the ore and difficulty in producing high-grade ferronickel. In addition, a large amount of iron discharged from electric furnace slag (reduction) may take away part of nickel, resulting in a reduced recovery rate of nickel. During the sulfurating and blowing of the low-grade ferronickel, a large amount of iron needed to be discharged through slagging. An amount of nickel taken away by the slag was increased, and the recovery rate of nickel was reduced.

[0092] A method for producing battery-grade nickel sulfate by using laterite nickel ore provided in the present disclosure has been described in detail above. The principle and implementations of the present disclosure are described herein by using specific examples. The descriptions of the foregoing examples are merely used for helping understand the method and core ideas, including the best way of the present disclosure, and also enable any person skilled in the art to practice the present disclosure, including manufacturing and using any device or system, and implementing any combined method. It should be noted that a person of ordinary skill in the art may further make several improvements and modifications without departing from the principle of the present disclosure. These improvements and modifications also fall within the protection scope of the claims of the present disclosure. The protection scope of the present disclosure is subject to the claims, and may include other examples that those skilled in the art may conceive of If these other examples have structural elements that are not different from the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, these other examples should also be included in the scope of the claims.