Method for extracting nickel, cobalt and manganese from laterite nickel ore by means of acid leaching

Abstract

A method for extracting nickel, cobalt and manganese from a laterite nickel ore by means of acid leaching. The method comprises the following steps: firstly, crushing a laterite nickel ore, then subjecting same to a physical separation treatment to separate out chromite and a first tailing, and then subjecting the first tailing to a graded concentration treatment, so as to obtain a first ore pulp; then subjecting the first ore pulp to a normal-pressure acid leaching treatment, so as to obtain a second ore pulp; and then subjecting the second ore pulp to a microwave treatment, and finally subjecting the second ore pulp to a solid-liquid separation treatment, so as to obtain tailings and a leachate containing nickel, cobalt and manganese. In the method for extracting nickel, cobalt and manganese from a laterite nickel ore by means of acid leaching, firstly, the chromite is preferentially separated out by means of a physical separation method, thereby reducing chromium metal entry into a normal-pressure acid leaching section; then, by means of adding an acid and mixing the pulp in advance, the first ore pulp and the acid reach a good environment, which is beneficial to the leaching of nickel, cobalt and manganese metals; and finally, solid particles in the second ore pulp can be energized by means of a microwave heating method, which is beneficial to the leaching of nickel, cobalt and manganese metals from the second ore pulp.

Description

Method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching Technical Field

[0001] The present invention relates to the field of nickel-cobalt-manganese material production, and in particular to a method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching. Background Art

[0002] With the rapid development of the battery industry, the global demand for nickel, cobalt and manganese has increased sharply, the prices of nickel, cobalt and manganese have risen sharply, and high-grade nickel, cobalt and manganese resources have become increasingly depleted. People have focused on developing low-grade, complex laterite nickel ore to produce nickel, cobalt and manganese raw materials for ternary power batteries.

[0003] Currently, nickel is primarily extracted from low-nickel laterite nickel ores through hydrometallurgical methods, with the mainstream processes being high-pressure acid leaching and atmospheric pressure acid leaching. The atmospheric pressure leaching process for laterite nickel ore offers advantages such as a short construction period, simple process, ease of operation, and low energy consumption. However, it suffers from issues such as low leaching rates of nickel, cobalt, and manganese, long leaching cycles, high acid consumption, and high iron content in the leachate. Therefore, research on how to improve the leaching rates of nickel, cobalt, and manganese from laterite nickel ore is key to extracting these metals through atmospheric pressure acid leaching.

[0004] Therefore, there is an urgent need for a method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore to solve the above technical problems.

[0005] Summary of the Invention

[0006] The object of the present invention is to provide a method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore, which is used to improve the technical problem of low leaching rate of nickel, cobalt and manganese metals extracted in the atmospheric pressure acid leaching stage during the existing hydrometallurgical production of nickel, cobalt and manganese hydroxide.

[0007] To solve the above technical problems, the present invention provides a method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore, comprising the following steps:

[0008] S10, performing physical separation after crushing the laterite nickel ore to separate the chromite ore and the first tailings;

[0009] S20, performing a graded concentration process on the first tailings to obtain a first ore pulp;

[0010] S30, performing normal pressure acid leaching on the first slurry to obtain a second slurry;

[0011] S40, performing solid-liquid separation on the second slurry to obtain tailings and a leachate containing nickel, cobalt and manganese;

[0012] Before performing step S40, the method further includes: subjecting the second slurry to microwave treatment.

[0013] Preferably, step S10 specifically includes:

[0014] S101, crushing the laterite nickel ore to obtain a first concentrate;

[0015] S102, performing gravity separation on the first concentrate to obtain a first chromite ore and a second concentrate;

[0016] S103, performing magnetic separation on the second concentrate to obtain a second chromite ore and a first tailings.

[0017] Preferably, in step S101, the particle size of the first concentrate is less than 1.5 mm.

[0018] Preferably, in step S102, the equipment used for the gravity separation process is a shaking table concentrator.

[0019] Preferably, in step S103, the equipment used for magnetic separation treatment is a wet magnetic separator, and the magnetic separation treatment adopts two-stage magnetic separation, the magnetic field strength range of the first stage magnetic separation is 400-500kA / m, and the magnetic field strength range of the second stage magnetic separation is 70-80kA / m.

[0020] Preferably, in step S10, the mass percentage of chromium in the first tailings is less than 0.1%, and the mass ratio of the first tailings added to the -200 mesh throughput is in the range of 90% to 95%.

[0021] Preferably, step S20 specifically includes:

[0022] The first tailings are pre-classified using a hydrocyclone. Fine particles and liquid fluid in the first tailings are directly discharged through the overflow port of the hydrocyclone to obtain slurry A. Coarse particles in the first tailings are ground in a mill and then discharged through the overflow port with liquid fluid to obtain slurry B. Slurry A and slurry B are combined to form the first slurry.

[0023] Preferably, in step S20, the mass ratio of solid particles in the first slurry is in the range of 20% to 30%.

[0024] Preferably, step S30 specifically includes:

[0025] S301, adding an acidic solution to the first slurry and stirring to obtain a second slurry;

[0026] The acidic solution is at least one of sulfuric acid, nitric acid and hydrochloric acid, the mass ratio of the acidic substance in the acidic solution is in the range of 10% to 25%, and the stirring treatment time is in the range of 20 to 40 minutes.

[0027] Preferably, the step of subjecting the second slurry to microwave treatment specifically includes: placing the second slurry in a microwave reactor for heating and stirring treatment, the power range of the microwave reactor is 400-800W, the stirring speed range is 200-300r / min, and the heating reaction time range is 1-3h.

[0028] The beneficial effect of the present invention is that, different from the prior art, the present invention provides a method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore, comprising the following steps: first, performing physical sorting treatment on the laterite nickel ore after crushing to separate chromite and a first tailing, then performing graded concentration treatment on the first tailing to obtain a first slurry, then performing normal pressure acid leaching treatment on the first slurry to obtain a second slurry, then performing microwave treatment on the second slurry, and finally performing solid-liquid separation treatment on the second slurry to obtain tailings and a leachate containing nickel, cobalt and manganese; the method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore provided by the present invention first preferentially separates chromite by a physical sorting method, thereby reducing the entry of chromium metal into the normal pressure acid leaching section; then, by pre-adding acid to adjust the slurry, the first slurry and the acid reach a good environment, which is conducive to the leaching of nickel, cobalt and manganese metals; finally, microwave heating is used to energize the solid particles in the second slurry, which is more conducive to the leaching of nickel, cobalt and manganese metals in the second slurry, thereby effectively improving the leaching rate of nickel, cobalt and manganese in the leachate. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a flow chart of a method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching provided by an embodiment of the present invention;

[0030] FIG2 is a process flow chart of a method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0032] Please refer to FIG1 , which is a simplified flow chart of a method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching according to an embodiment of the present invention. The method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching specifically comprises:

[0033] S10: After the laterite nickel ore is crushed, it is physically sorted to separate the chromite and the first tailings.

[0034] Specifically, step S10 further includes:

[0035] First, a laterite nickel ore is provided, wherein the laterite nickel ore is limonite-type laterite nickel ore, residual ore-type laterite nickel ore, or a mixture of the two minerals.

[0036] Afterwards, the laterite nickel ore is crushed by a crusher to obtain a first concentrate, wherein the particle size of the first concentrate is less than 1.5 mm; the particle size of the first concentrate less than 1.5 mm is conducive to subsequent classification and concentration processing.

[0037] Afterwards, the first concentrate is subjected to gravity separation to obtain a first chromite ore with a first particle size and a second concentrate; gravity separation, also known as gravity separation, refers to a mineral separation method that utilizes the differences in relative density, particle size, shape between the mineral particles to be separated, as well as the differences in their movement speed and direction in a medium (water, air or other relatively dense liquids) to separate them from each other.

[0038] Specifically, the equipment used in the gravity separation process is a shaking table concentrator, and the gravity separation process can be used to roughly separate the first chromite in the first concentrate according to the effect of gravity and separate the second concentrate.

[0039] Finally, the second concentrate is subjected to magnetic separation to obtain a first chromite ore having a second particle size and a first tailing, wherein the second particle size is smaller than the first particle size. Preferably, the magnetic separation is performed using a wet magnetic separator, and the magnetic separation employs a two-stage magnetic separation process, wherein the magnetic field strength of the first stage is in the range of 400 to 500 kA / m, and the magnetic field strength of the second stage is in the range of 70 to 80 kA / m.

[0040] Among them, the secondary magnetic separation treatment can further roughly separate the remaining chromite (second chromite) in the second concentrate according to the effect of the magnetic field and separate it to obtain the first tailings.

[0041] Preferably, in step S10, the mass percentage of chromium in the first tailings is less than 0.1%, and the mass ratio of the first tailings added to the -200 mesh throughput is in the range of 90% to 95%.

[0042] Furthermore, the first tailings obtained by physical separation after crushing the laterite nickel ore have a relatively low iron and chromium content, which can reduce the amount of iron and chromium metal entering the atmospheric pressure acid leaching stage.

[0043] S20: performing a graded concentration treatment on the first tailings to obtain a first ore slurry.

[0044] Specifically, step S20 further includes:

[0045] The first tailings are pre-classified using a hydrocyclone. Fine particles and liquid fluid in the first tailings are directly discharged through the overflow port of the hydrocyclone to obtain slurry A. Coarse particles in the first tailings are ground in a mill and then discharged through the overflow port with liquid fluid to obtain slurry B. Slurry A and slurry B are combined to form the first slurry.

[0046] Preferably, in step S20, the mass ratio of solid particles in the first slurry is in the range of 20% to 30%.

[0047] Specifically, step S20 can create a favorable environment between the first slurry and the acid, which is beneficial to the leaching of nickel, cobalt and manganese metals.

[0048] S30, performing normal pressure acid leaching on the first slurry to obtain a second slurry.

[0049] Specifically, step S30 further includes:

[0050] An acidic solution is added to the first slurry and stirred to produce a second slurry. The acidic solution is at least one of sulfuric acid, nitric acid, and hydrochloric acid, the mass ratio of the acidic substance in the acidic solution ranges from 10% to 25%, and the stirring time ranges from 20 to 40 minutes. The acidic solution is added to the first slurry to dissolve the nickel, cobalt, and manganese metals.

[0051] S40, performing solid-liquid separation on the second slurry to obtain tailings and a leaching solution containing nickel, cobalt and manganese.

[0052] Specifically, step S40 further includes:

[0053] First, the second slurry is placed in a microwave reactor for heating treatment, and the power range of the microwave reactor is 400-800W;

[0054] Afterwards, heating the reaction for a period of time under certain temperature and stirring speed conditions, wherein the stirring speed range is 200-300 r / min, the temperature range is 85-100° C., and the heating time range is 1-3 h;

[0055] Finally, the second slurry is subjected to solid-liquid separation treatment (filtration method) to obtain tailings and a leaching solution containing nickel, cobalt and manganese; wherein the tailings are washed with hot water 4 to 5 times, and the washing solution is mixed into the leaching solution containing nickel, cobalt and manganese.

[0056] Specifically, when the microwave reactor performs microwave heating on the second slurry, the microwaves can quickly penetrate and directly store heat in the solid minerals of the second slurry, which can accelerate the temperature rise of the solid minerals and is more conducive to the leaching of nickel, cobalt and manganese metals.

[0057] The technical solution of the present application is now described in conjunction with specific embodiments. The laterite nickel ore in all the following implementation cases and comparative examples is selected from limonitic laterite nickel ore, and the mass percentage content of each metal component is as follows: the mass percentage content of the Ni component is 1.18%, the mass percentage content of the Co component is 0.075%, the mass percentage content of the Mn component is 0.568%, the mass percentage content of the Cr component is 1.73%, the mass percentage content of the Fe component is 41.70%, the mass percentage content of the Al component is 4.29%, and the mass percentage content of the Mg component is 1.68%.

[0058] Embodiments of the present invention:

[0059] Please refer to FIG2 , which is a process flow chart of a method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching according to an embodiment of the present invention, comprising the following steps:

[0060] S10: After the laterite nickel ore is crushed, it is physically sorted to separate the chromite and the first tailings.

[0061] Specifically, step S10 further includes:

[0062] First, the laterite nickel ore is crushed by a crusher to obtain a first concentrate, wherein the particle size of the first concentrate is less than 1.5 mm.

[0063] Afterwards, the first concentrate is subjected to gravity separation by a shaking table concentrator to obtain a first chromite ore and a second concentrate;

[0064] Finally, the second concentrate is subjected to magnetic separation to obtain the second chromite and the first tailings. The magnetic separation process uses a wet magnetic separator with two stages. The first stage has a magnetic field strength of 450kA / m and is used for rough separation of the chromite in the second concentrate. The second stage has a magnetic field strength of 80kA / m and is used for secondary separation of the remaining chromite in the second concentrate to obtain the second concentrate.

[0065] Specifically, after step S10 is completed, the recovery rate of the obtained chromite is 46.23%, and the mass percentage of Cr2O3 in the chromite is 43.22%; the mass ratio of the first tailings obtained by sorting to the -200 mesh throughput is 90%.

[0066] S20: performing a graded concentration treatment on the first tailings to obtain a first ore slurry.

[0067] Specifically, step S20 further includes:

[0068] A hydrocyclone is used to pre-classify the first tailings, and the fine particles and liquid fluid in the first tailings are directly discharged through the overflow port of the hydrocyclone to obtain slurry A; the coarse particles in the first tailings are ground in a grinding mill and then discharged through the overflow port with the liquid fluid to obtain slurry B; slurry A and slurry B are combined to form a first slurry; wherein, in step S20, the mass percentage of solid particles in the first slurry is 25%.

[0069] S30, performing normal pressure acid leaching on the first slurry to obtain a second slurry.

[0070] Specifically, step S30 further includes:

[0071] An acidic solution is added to the first slurry and stirred to obtain a second slurry; wherein the acidic solution is a concentrated sulfuric acid aqueous solution, the mass concentration of the acidic substance in the concentrated sulfuric acid aqueous solution is 150 g / L, the stirring time is 30 minutes, and the stirring speed is 150 r / min.

[0072] S40, performing solid-liquid separation on the second slurry to obtain tailings and a leaching solution containing nickel, cobalt and manganese.

[0073] Specifically, step S40 further includes:

[0074] First, the second slurry was heated in a microwave reactor at 600W. The reaction was then heated at 90°C for a period of 2.5 hours with a stirring speed of 250 r / min. Finally, the second slurry was subjected to solid-liquid separation (filtration) to obtain tailings and a leachate containing nickel, cobalt, and manganese. The tailings were washed five times with hot water, and the washings were mixed into the leachate containing nickel, cobalt, and manganese. The washed tailings were dried, weighed, and analyzed for composition. Results showed that after the acid leaching method, the leaching yields of nickel were 88.2%, cobalt were 79.5%, and manganese were 90.34%.

[0075] Comparative Example:

[0076] The method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching provided in the comparative example is substantially the same as the method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching provided in the embodiment of the present invention, except that:

[0077] In step S40, the second slurry is subjected to solid-liquid separation to obtain tailings and a leachate containing nickel, cobalt and manganese;

[0078] Specifically, the second slurry was heated to 90°C in a water bath and stirred at 250 r / min for 2.5 hours. The second slurry was then subjected to solid-liquid separation (filtration) to produce tailings and a leachate containing nickel, cobalt, and manganese. The tailings were washed five times with hot water, and the washings were mixed into the leachate containing nickel, cobalt, and manganese. The washed tailings were dried, weighed, and their composition analyzed.

[0079] The final results show that after being treated by the method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore provided in the comparative example, the leaching rate of Ni is 78.2%, the leaching rate of Co is 64.3%, and the leaching rate of Mn is 82.52%.

[0080] By comparison, it can be seen that in step S40, using a microwave reactor to perform microwave heating on the second slurry is more conducive to the leaching of nickel, cobalt and manganese metals in the second slurry than using a water bath to perform water bath heating on the second slurry.

[0081] Compared with the prior art, the method for extracting nickel, cobalt and manganese from laterite nickel ore by acid leaching provided in the embodiment of the present invention has the following advantages:

[0082] First, the advantage of the present invention is that it combines the methods of mineral processing and hydrometallurgy to achieve efficient recovery of metals such as nickel, cobalt, manganese and chromium from laterite nickel ore;

[0083] Secondly, the advantage of the present invention is that the chromite is pre-separated from the laterite nickel ore by "gravity separation + magnetic separation", which is conducive to the recovery of chromium metal and significantly reduces the chromium metal ions in the leachate after atmospheric pressure acid leaching;

[0084] Third, the advantage of the present invention is that it uses microwave heating to quickly charge the mineral interior, promoting the leaching of nickel, cobalt and manganese metals in laterite nickel ore, which is of great significance to the technology of extracting nickel, cobalt and manganese metals by atmospheric pressure leaching of laterite nickel ore.

[0085] Compared with the prior art, the present invention provides a method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore, comprising the following steps: first, after crushing the laterite nickel ore, performing physical sorting treatment to separate chromite and a first tailing, then performing graded concentration treatment on the first tailing to obtain a first slurry, then performing atmospheric pressure acid leaching treatment on the first slurry to obtain a second slurry, then performing microwave treatment on the second slurry, and finally performing solid-liquid separation treatment on the second slurry to obtain tailings and a leachate containing nickel, cobalt and manganese; the method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore provided by the present invention first preferentially separates chromite by a physical sorting method to reduce the entry of chromium metal into the atmospheric pressure acid leaching section; then, by pre-adding acid to adjust the slurry, the first slurry and the acid reach a good environment, which is conducive to the leaching of nickel, cobalt and manganese metals; finally, microwave heating is used to energize the solid particles in the second slurry, which is more conducive to the leaching of nickel, cobalt and manganese metals in the second slurry, thereby effectively improving the leaching rate of nickel, cobalt and manganese in the leachate.

[0086] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For any details not described in individual embodiments, reference may be made to the description in other embodiments.

[0087] The above embodiments merely illustrate the implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore, characterized in that: The method comprises the following steps: S10, performing physical separation after crushing the laterite nickel ore to separate the chromite ore and the first tailings; S20, performing graded concentration treatment on the first tailings to obtain a first ore pulp; S30, performing normal pressure acid leaching on the first slurry to obtain a second slurry; S40, performing solid-liquid separation treatment on the second slurry to obtain tailings and a leaching solution containing nickel, cobalt and manganese; Wherein, before performing the step S40, the method further includes: subjecting the second slurry to microwave treatment.

2. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 1, characterized in that: The step S10 specifically includes: S101, crushing the laterite nickel ore to obtain a first concentrate; S102, performing gravity separation on the first concentrate to obtain a first chromite ore and a second concentrate; S103, performing magnetic separation on the second concentrate to obtain a second chromite ore and the first tailings.

3. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 2, characterized in that: In the step S101, the particle size of the first concentrate is less than 1.5 mm.

4. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 2, characterized in that: In the step S102, the equipment used for the gravity separation process is a shaking table concentrator.

5. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 2, characterized in that: In the step S103, the equipment used for the magnetic separation treatment is a wet magnetic separator, and the magnetic separation treatment adopts two-stage magnetic separation, the magnetic field strength range of the first stage magnetic separation is 400-500 kA / m, and the magnetic field strength range of the second stage magnetic separation is 70-80 kA / m.

6. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 2, characterized in that: In the step S10, the mass percentage of chromium in the first tailings is less than 0.1%, and the mass ratio of the first tailings added to the -200 mesh throughput is in the range of 90% to 95%.

7. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 1, characterized in that: The step S20 specifically includes: The first tailings are pre-classified by a hydrocyclone, and the fine particles in the first tailings are The particles and the liquid fluid are directly discharged through the overflow port of the hydrocyclone to obtain slurry A; the coarse particles in the first tailings are finely ground in the mill and then discharged through the overflow port with the liquid fluid to obtain slurry B; the slurry A and the slurry B are combined to form the first slurry.

8. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 7, characterized in that: In the step S20, the mass ratio of solid particles in the first slurry is in the range of 20% to 30%.

9. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 1, characterized in that: The step S30 specifically includes: S301, adding an acidic solution to the first slurry, and stirring to obtain the second slurry; The acidic solution is at least one of sulfuric acid, nitric acid and hydrochloric acid, the mass ratio of the acidic substance in the acidic solution is in the range of 10% to 25%, and the stirring treatment time ranges from 20 to 40 minutes.

10. The method for extracting nickel, cobalt and manganese by acid leaching of laterite nickel ore according to claim 1, characterized in that: The step of subjecting the second slurry to microwave treatment specifically includes: placing the second slurry in a microwave reactor for heating and stirring treatment, the microwave reactor has a power range of 400 to 800 W, a stirring speed range of 200 to 300 r / min, and a heating reaction time range of 1 to 3 h.

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