Laterite-nickel ore washing process and system

Abstract

The invention discloses a laterite-nickel ore washing process and system, and the laterite-nickel ore washing method provided by the invention comprises the following steps: introducing laterite-nickel ore into a cylindrical ore washer by adopting a mechanical ore unloading method for ore washing and pulping, and washing and screening the obtained cylindrical discharge ore pulp by a vibrating screen to obtain the finished ore washing ore pulp. According to the ore washing method, a groove type scrubbing machine which is poor in operation stability in the traditional ore washing process is omitted, meanwhile, the mud-containing gravels on the vibrating screen are intensively washed through the washing effect on the vibrating screen, and the washing effect is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of ore washing, and in particular to a laterite nickel ore washing process and system. Background Art

[0002] The morphology of laterite nickel ore is mainly soil-based. After mining, it needs to be beneficiated for subsequent smelting such as wet acid leaching. The beneficiation of laterite nickel ore usually includes washing, chromite selection (chromite removal) and concentration. The purpose of washing is to separate the coarse ore in the laterite nickel ore.

[0003] In the traditional laterite nickel ore washing method, the washing process of laterite nickel ore includes: washing with a drum washer and washing with a trough scrubber in sequence, so as to separate the coarse ore (including waste rock and ore with larger particle size) in the laterite nickel ore from the laterite nickel ore slurry, and the washed laterite nickel ore enters the chromium selection and concentration process. However, due to the large amount of gravel and debris in the laterite nickel ore, the trough scrubber has a high failure rate, which seriously affects the production efficiency of the entire line. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a laterite nickel ore washing process and system.

[0005] The present invention solves the technical problem by adopting the following technical solutions.

[0006] The invention provides a laterite nickel ore washing process, which comprises: introducing the laterite nickel ore into a drum ore washer for ore washing and pulping by a mechanical ore unloading method, washing and screening the obtained drum discharge ore pulp by a vibrating screen, and obtaining the washed ore finished product ore pulp.

[0007] The present invention also provides a laterite nickel ore washing system, comprising: a drum ore washer, the drum ore washer having an original ore inlet, a drum discharge ore slurry outlet and a large gravel outlet; and a vibrating screen, the vibrating screen having a drum discharge ore slurry inlet, a small gravel outlet and a finished ore slurry outlet for washing, a water spraying device is provided above the vibrating screen, and the vibrating screen is arranged on the downstream side of the drum ore washer along the flow direction of the ore washing process, and the drum discharge ore slurry inlet is connected to the drum discharge ore slurry outlet of the drum ore washer.

[0008] The present invention has the following beneficial effects:

[0009] The present invention provides a laterite nickel ore washing process and system. The laterite nickel ore washing method provided by the present invention comprises: introducing the laterite nickel ore into a drum ore washer for washing and pulping by a mechanical unloading method, and the obtained drum discharge ore pulp is washed and screened by a vibrating screen to obtain a finished washed ore pulp. The above-mentioned ore washing method eliminates the trough scrubber with poor operating stability in the traditional ore washing process, and the drum discharge ore pulp obtained by washing and pulping with the drum ore washer is subjected to the vibration, washing and screening action of the vibrating screen to strengthen the washing of muddy gravel on the vibrating screen to ensure the washing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0011] Figure 1 A flow chart of a laterite nickel ore washing method;

[0012] Figure 2 Schematic diagram of the laterite nickel ore washing system. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0014] A laterite nickel ore washing process and system provided in an embodiment of the present invention are specifically described below.

[0015] In a first aspect, an embodiment of the present invention provides a laterite nickel ore washing process, which comprises: introducing the laterite nickel ore into a drum ore washer for ore washing and pulping by a mechanical unloading method, and the obtained drum discharge slurry is washed and screened by a vibrating screen to obtain a finished ore washing slurry.

[0016] Laterite nickel ore, especially "wet type" laterite nickel ore, has the characteristics of high water content and high viscosity, and is accompanied by a certain proportion of gravel of different particle sizes. In addition, the tropical rainforest climate in the distribution area of ​​"wet type" laterite nickel ore has a great impact on the mining operation time. How to continuously and effectively produce laterite nickel ore or slurry on the basis of adapting to the local climate is an urgent problem to be solved.

[0017] In the traditional process, the washing process of laterite nickel ore is: washing with a cylindrical ore washer + washing with a trough scrubber + screening with a vibrating screen. The operation stability of this process is poor, and the failure rate of the trough scrubber is high, resulting in high washing costs and low washing efficiency. In severe cases, it will affect the production capacity of the entire line and bring huge economic losses. The main reason is that laterite nickel ore basically contains gravel, and the gravel has a relatively large particle size and hardness. In addition, it was found during the production process that since laterite nickel ore is a difficult-to-wash ore with a fine particle size and high viscosity, during the washing process of laterite nickel ore, the slurry cylinder of the cylindrical ore washer has insufficient soaking effect on the original ore and weak scrubbing effect, so it is easy for clay balls with large particle size to appear in the cylindrical ore washer, especially for laterite nickel ore with high viscosity and high moisture content. Under the influence of the above-mentioned multiple factors, the traditional method is used to wash the laterite nickel ore in the drum ore washer, and then the obtained drum discharge slurry is input into the trough scrubber for scrubbing to separate the return sand. Since the drum discharge slurry obtained by the drum ore washer contains a large amount of gravel, large-size clay balls, etc., during the scrubbing process of the trough scrubber, problems such as failures of spiral bearings, spiral blades, motors, reducers, and chute blockages often occur, which brings many troubles to the ore washing production and even the entire production line.

[0018] In order to reduce the failure rate, improve the washing efficiency and the production efficiency of the whole line, the present invention provides a laterite nickel ore washing process, the main process flow is: mechanical ore unloading + drum ore washing + vibrating screen washing and screening, the trough scrubber with poor operating stability is eliminated, and the muddy gravel on the vibrating screen is strengthened by washing to ensure the washing effect. Specifically:

[0019] In the unloading process, due to the obvious existence of rainy seasons and dry seasons in the distribution area of ​​"wet" laterite nickel ore, the inventor has proposed through practice that different mining methods should be adopted according to different climatic characteristics. In the dry season, mechanical unloading is mainly adopted for unloading. The mechanical unloading method usually adopts a single bucket-truck intermittent production process. The mining production is highly flexible, with the mining site as the production unit, covering a large area, and can be arbitrarily adjusted according to different on-site conditions, and the ore distribution is flexible.

[0020] In the ore washing process, the solution provided by the embodiment of the present invention is to directly send the mined laterite nickel ore into the drum ore washer for soaking, washing and scrubbing, so as to separate large pieces of large gravel, and the separated large gravel has very little fine-grained ore, and the coarse and fine particle separation effect is good, and then the obtained drum discharge ore slurry is directly sent to the vibrating screen for washing and screening without being scrubbed by the scrubbing machine. Since the drum discharge ore slurry obtained by washing the ore with the drum ore washer is distributed on the entire screen surface, there will be no problems such as high failure rate of spiral bearings, spiral blades, motors, reducers, etc. and chute blockage in the scrubbing process of the trough scrubbing machine. After the trough scrubbing machine is eliminated, the ore washing process can be carried out smoothly and continuously, shortening the ore washing process, reducing the floor space, reducing the ore washing cost, and also improving the ore washing operation. rate, full-line capacity, etc.; and the materials on the vibrating screen can be more easily washed off the fine-grained mud attached to the surface of the muddy ore under the action of strong flushing and vibration, and the separation effect of the ore and the mud attached to the surface of the ore is good. The test results show that the mud content of small gravel and the nickel recovery rate in the finished ore pulp obtained by enhanced flushing and screening with the vibrating screen are the same or similar to the results obtained by the washing process of the drum ore washer + trough scrubber + vibrating screen screening, and the washing effect is good; in addition, in the washing process of the drum ore washer + trough scrubber + vibrating screen screening, the overflow and return sand obtained by scrubbing with the trough scrubber need to be screened separately in different vibrating screens, and the undersize materials screened by different vibrating screens are combined again to obtain the finished ore pulp of the washing. The scheme provided by the embodiment of the present invention is that the cylindrical discharge slurry discharged from the cylindrical ore washer directly enters the screen surface of the vibrating screen for enhanced washing and vibration screening. The vibrating screen is located on both sides of the cylindrical ore washer. The ore washing equipment in the entire ore washing process is compact and occupies a small area, which not only shortens the ore washing process and reduces the ore washing cost, but also greatly improves the processing capacity and ore washing operation rate of laterite nickel ore; the scheme provided by the embodiment of the present invention can also obtain the ore washing finished pulp, which can be directly used for hydrometallurgy after simple treatment, shortening the hydrometallurgy process and reducing production costs. It can be seen that the laterite nickel ore washing process provided by the present invention has a simple process and high production efficiency, while reducing equipment investment, maintenance cost, operating cost, and floor space, effectively reducing the ore washing cost of laterite nickel ore hydrometallurgy. In addition, the production capacity scale of laterite nickel ore hydrometallurgy plants continues to expand, and the single specification capacity of the trough scrubber equipment has been difficult to increase, and cannot meet the requirements of the single capacity of the washing equipment for larger-scale laterite nickel ore hydrometallurgy; the present invention provides a more optimized ore washing scheme.

[0021] In some optional embodiments, the laterite nickel ore washing process includes: unloading the laterite nickel ore by a mechanical unloading method to obtain an ore pile, and sending the fine-grained minerals after grading or screening of the ore pile into a drum washer for washing and pulping; and / or, unloading the laterite nickel ore directly to the grating feed port by a mechanical unloading method for grading or screening, and sending the fine-grained minerals after grading or screening into a drum washer for washing and pulping; and then washing and screening the obtained drum discharge slurry through a vibrating screen to obtain a finished washed ore slurry.

[0022] It should be noted here that some laterite nickel ores are loaded from the ore pile (raw ore pile) at the production site, and some laterite nickel ores are pulled back from the mine or dock by dump trucks and directly unloaded into the loading port (without stockpiling).

[0023] In some optional embodiments, the laterite nickel ore washing process comprises the following steps:

[0024] The laterite nickel ore is unloaded by a mechanical unloading method to obtain a raw ore pile, and the raw ore pile is screened by a grating to obtain the raw ore and coarse gravel for storage; and / or, the laterite nickel ore is directly unloaded to the grating feeding port by a mechanical unloading method to obtain the raw ore and coarse gravel for storage;

[0025] The raw ore entering the warehouse is sent to the drum ore washer for ore washing and pulping to obtain drum discharge ore pulp and large gravel;

[0026] The drum discharge slurry is then introduced into the vibrating screen for washing and screening to obtain finished slurry and small gravel.

[0027] In some optional embodiments, the laterite nickel ore is limonite-type laterite nickel ore and contains gravels of different particle sizes.

[0028] In some optional embodiments, the grid screen is screened using a heavy-duty grid screen, and the width of the sieve holes on the heavy-duty grid screen is 300-400 mm, and the length is 300-1000 mm.

[0029] The embodiment of the present invention provides a laterite nickel ore washing method, in which a heavy-duty grid screen is used for grating screening. The grid screen screening step can screen out coarse gravel in the laterite nickel ore, which can not only improve the safety of subsequent production, but also reduce the ore feed amount in the drum ore washer and improve production efficiency.

[0030] In some optional embodiments, the ore washing pulping adopts a drum plus screen bar type drum ore washing machine for ore washing, and the drum plus screen bar type drum ore washing machine includes a washing section and a screening section. The width of the sieve hole of the screening section of the drum ore washing machine is 10-50mm, and the length is 10-500mm.

[0031] The embodiment of the present invention provides a laterite nickel ore washing method, in which a drum washing machine adopts a drum plus screen bar type drum washing machine for washing ore, pulping and screening. Compared with the full screening process and the screen plus slot washing machine process, the drum plus screen bar type drum washing machine performs two-stage scrubbing, and has a better washing effect. The drum washing machine has the dual functions of washing and screening, and can handle large pieces of ore. The above-mentioned screening step can screen out large gravels in the screened ore pulp.

[0032] In some optional embodiments, the flushing and screening is performed using a linear vibrating screen with a water spray device, and the width of the sieve holes on the linear vibrating screen is 1-5 mm and the length is 1-50 mm.

[0033] The embodiment of the present invention provides a laterite nickel ore washing method. In the embodiment of the present invention, the cylindrical discharge slurry after screening in the cylindrical ore washer is directly sent to the linear vibrating screen for washing and screening. The cylindrical discharge slurry is distributed on the entire screen surface, so there will be no problems such as high failure rate of spiral bearings, spiral blades, motors, reducers, etc. and blockage of the chute; secondly, the screen material of the linear vibrating screen can not only generate reciprocating linear trajectory vibration in the longitudinal axis direction, but also make the screen surface perform directional reciprocating linear vibration, thereby effectively improving the screening efficiency of the linear vibrating screen and reducing the screening cost; thirdly, the screen material of the linear vibrating screen is subjected to the hydraulic enhanced washing action, and high-pressure washing water is ejected at high speed, so that the slurry bonded together is separated into ore particles, and the ore particles with a particle size smaller than the pore size of the screen hole pass through the screen hole and fall into the finished ore slurry storage tank below.

[0034] As can be seen from the above, the laterite nickel ore washing method provided by the embodiment of the present invention has the following advantages: (1) the wiping scrubber with poor operating stability is eliminated, the process flow is simple, and the footprint is small; (2) the equipment investment, maintenance cost, and operating cost of the trough scrubber are saved, and the washing cost of the laterite nickel ore wet smelting is effectively reduced; (3) the production efficiency of the entire line is improved.

[0035] In the second aspect, an embodiment of the present invention also provides a laterite nickel ore washing system, comprising: a drum ore washer, the drum ore washer having an original ore inlet, a drum discharge ore slurry outlet and a large gravel outlet; and a vibrating screen, the vibrating screen having a drum discharge ore slurry inlet, a small gravel outlet and a finished ore slurry outlet for washing, a water spraying device is provided above the vibrating screen, and the vibrating screen is arranged on the downstream side of the drum ore washer along the flow direction of the ore washing process, and the drum discharge ore slurry inlet is connected to the drum discharge ore slurry outlet of the drum ore washer.

[0036] In some optional embodiments, there are multiple water spraying devices above the vibrating screen.

[0037] In some optional embodiments, it further includes a ore bin for storing laterite nickel ore, the top of the ore bin is open and a grid is arranged on the top.

[0038] In some optional embodiments, a loader is further included, which is used to transfer the raw ore or incoming raw ore on the raw ore pile to the grid screen feeding port for grading or screening, and transfer the coarse gravel on the ore bin grid screen to the coarse gravel yard.

[0039] In some optional embodiments, it further includes an iron plate feeder, which is arranged between the ore bin and the drum ore washer to transport the laterite nickel ore from the ore bin to the drum ore washer, and the discharge port of the ore bin is connected to the feed port of the iron plate feeder.

[0040] In some optional embodiments, it further includes a first belt conveyor and a second belt conveyor, the first belt conveyor is used to transfer the large gravel at the large gravel outlet of the drum ore washer to the large gravel yard, and the second belt conveyor is used to transfer the small gravel outlet on the vibrating screen to the small gravel yard.

[0041] In some optional embodiments, the number of the drum washers is one or more.

[0042] In some optional embodiments, the method further includes a finished ore washing slurry storage tank disposed below the finished ore washing slurry outlet of the vibrating screen.

[0043] The present invention will be further described below in conjunction with the embodiments.

[0044] Example 1

[0045] A laterite nickel ore washing process, see Figure 1 , including the following steps:

[0046] The laterite nickel ore is poured into the heavy-duty grid screen at the top of the ore bin by a loader for grid screening. The mesh width of the heavy-duty grid screen is 350 mm and the length is 350 mm, and the ore entering the bin and coarse gravel are obtained; the ore entering the bin enters the drum ore washer through a heavy plate feeder for ore washing, pulping and screening. The mesh width of the screening section of the drum ore washer is 25 mm and the length is 100 mm, and the drum discharge slurry and large gravel are obtained; the drum discharge slurry flows by gravity to the linear vibrating screen for enhanced washing and screening. The mesh width of the linear vibrating screen is 3 mm and the length is 20 mm, and the washed finished ore slurry and small gravel are obtained. The mud content of small gravel (-100 mesh particle size ratio) is 1.6%, and the Ni yield of the washing process is 93.50%.

[0047] Example 2

[0048] A laterite nickel ore washing system, see Figure 2, including: a drum ore washer, the drum ore washer has an original ore inlet, a drum discharge ore slurry outlet and a large gravel outlet; and a vibrating screen, the vibrating screen has a drum discharge ore slurry inlet, a small gravel outlet and a finished ore slurry outlet for washing, a water spraying device is arranged above the vibrating screen, the number of the water spraying devices is multiple, and the vibrating screen is arranged on the downstream side of the drum ore washer along the flow direction of the ore washing process, and the drum discharge ore slurry inlet is connected to the drum discharge ore slurry outlet of the drum ore washer.

[0049] An ore bin for storing laterite ore is provided on the upstream side of the drum ore washer, and an iron plate feeder is provided between the ore bin and the drum ore washer. The iron plate feeder supplies the laterite ore in the ore bin to the drum ore washer through the ore material inlet of the drum ore washer.

[0050] It also includes: a loader, a first belt conveyor, a second belt conveyor and a finished ore washing slurry storage tank. The loader is used to transfer the raw ore or raw ore incoming materials on the raw ore pile to the grating screen feeding port for grading or screening, and transfer the coarse gravel on the ore bin grating screen to the coarse gravel yard. The first belt conveyor is used to transfer the large gravel at the large gravel outlet of the drum ore washer to the large gravel yard, the second belt conveyor is used to transfer the small gravel outlet on the vibrating screen to the small gravel yard, and the finished ore washing slurry storage tank is used to store the finished ore washing slurry under the vibrating screen.

[0051] Comparative Example 1

[0052] The steps are similar to those in Example 1, except that the sieve hole width of the cylindrical ore washer is 80 mm and the length is 100 mm, the discharge amount of large gravel is reduced, the amount of small gravel on the vibrating screen is greatly increased, and the flushing effect is poor. As a result, the mud content of small gravel increases to 4.6%, and the Ni recovery rate of the ore washing process is 93.26%.

[0053] Comparative Example 2

[0054] The steps are similar to those in Example 1, except that the washing water is removed from the vibrating screen, resulting in the small gravel mud content increasing to 16.8%, and the Ni yield in the washing process being 92.28%.

[0055] It can be seen from the above experimental results that compared with the ore washing method of drum washing + trough scrubbing + vibrating screen, the ore washing method provided by the embodiment of the present invention eliminates the trough scrubbing machine, greatly reduces the equipment failure rate, reduces equipment investment and operating costs, and improves production efficiency, while still achieving the same ore washing effect, thereby improving the ore washing operation rate and the overall production capacity.

[0056] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A laterite nickel ore washing process, characterized in that: It includes: The laterite nickel ore is introduced into the drum ore washer for ore washing and pulping by mechanical unloading method. The obtained drum discharge ore pulp is washed and screened by a vibrating screen to obtain the finished ore pulp.

2. The laterite nickel ore washing process according to claim 1, characterized in that: It includes: The laterite nickel ore is unloaded by a mechanical unloading method to obtain an ore pile, and the fine-grained minerals after classification or screening of the ore pile are sent to a drum ore washer for ore washing and pulping; and / or, the laterite nickel ore is directly unloaded to a grating feed port for classification or screening by a mechanical unloading method, and the fine-grained minerals after classification or screening are sent to a drum ore washer for ore washing and pulping; The obtained cylindrical discharge slurry is then washed and screened through a vibrating screen to obtain the finished ore washing slurry.

3. The laterite nickel ore washing process according to claim 1 or 2, characterized in that: The following steps are involved: The laterite nickel ore is unloaded by a mechanical unloading method to obtain a raw ore pile, and the raw ore pile is screened by a grid screen to obtain the raw ore and coarse gravel for storage; and / or, the laterite nickel ore is directly unloaded to the grid screen feeding port by a mechanical unloading method to obtain the raw ore and coarse gravel for storage; The raw ore entering the warehouse is sent to a drum ore washer for ore washing and pulping to obtain drum discharge ore pulp and large gravel; The cylinder discharge slurry is then introduced into a vibrating screen for washing and screening to obtain finished ore washing slurry and small gravel.

4. The laterite nickel ore washing process according to claim 3, characterized in that: The laterite nickel ore is a limonite-type laterite nickel ore and contains gravels of different particle sizes.

5. The laterite nickel ore washing process according to claim 3, characterized in that: The grid screen is screened using a heavy-duty grid screen, and the width of the sieve holes on the heavy-duty grid screen is 300-400 mm, and the length is 300-1000 mm.

6. The laterite nickel ore washing process according to claim 3, characterized in that: The ore washing pulping adopts a cylinder plus screen bar type cylinder ore washing machine for ore washing. The cylinder plus screen bar type cylinder ore washing machine includes a washing section and a screening section. The width of the sieve hole of the screening section of the cylinder ore washing machine is 10-50mm, and the length is 10-500mm.

7. The laterite nickel ore washing process according to claim 3, characterized in that: The flushing and screening is performed by using a linear vibrating screen with a water spraying device, and the screen holes on the linear vibrating screen have a width of 1-5 mm and a length of 1-50 mm.

8. A laterite nickel ore washing system, characterized in that: include: A drum ore washer, the drum ore washer having an inlet for raw ore, a drum discharge ore pulp outlet and a large gravel outlet; and a vibrating screen, the vibrating screen having a cylindrical discharge ore pulp inlet, a small gravel outlet and a finished ore pulp outlet for washing, a water spraying device is arranged above the vibrating screen, and the vibrating screen is arranged on the downstream side of the cylindrical ore washer along the flow direction of the ore washing process, and the cylindrical discharge ore pulp inlet is connected to the cylindrical discharge ore pulp outlet of the cylindrical ore washer.

9. The laterite nickel ore washing system according to claim 8, characterized in that: There are multiple water spray devices above the vibrating screen.

10. The laterite nickel ore washing system according to claim 8, characterized in that: It further comprises an ore bin for storing laterite nickel ore, wherein the top of the ore bin is open and a grid is arranged on the top.

11. The laterite nickel ore washing system according to claim 8, characterized in that: It further includes an iron plate feeder, which is arranged between the ore bin and the drum ore washer to transport the laterite nickel ore from the ore bin to the drum ore washer, and the discharge port of the ore bin is connected to the feed port of the iron plate feeder.

12. The laterite nickel ore washing system according to claim 8, characterized in that: It further comprises a loader, which is used to transfer the raw ore or incoming raw ore on the raw ore pile to the grid screen feeding port for grading or screening, and to transfer the coarse gravel on the ore bin grid screen to the coarse gravel yard.

13. The laterite nickel ore washing system according to claim 8, characterized in that: It further includes a first belt conveyor and a second belt conveyor, wherein the first belt conveyor is used to transfer the large gravel at the large gravel outlet of the drum ore washer to the large gravel yard, and the second belt conveyor is used to transfer the small gravel outlet on the vibrating screen to the small gravel yard.

14. The laterite nickel ore washing system according to claim 8, characterized in that: The number of the drum ore washers is one or more.

15. The laterite nickel ore washing system according to claim 8, characterized in that: It further includes a finished ore washing slurry storage tank arranged below the finished ore washing slurry outlet of the vibrating screen.

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