Acid feeding system for high-pressure kettle for laterite-nickel ore hydrometallurgy

Abstract

An acid feeding system for a high-pressure kettle for laterite-nickel ore hydrometallurgy, comprising: a liquid acid supply tank, an acid feeding pipeline, an acid feeding pump, pressurizers, and a high-pressure reaction kettle, wherein one end of the acid feeding pipeline is communication with the high-pressure reaction kettle, and the other end of the acid feeding pipeline is communicated with the liquid acid supply tank; the acid feeding pump is arranged on the acid feeding pipeline and used for pressurizing and pumping a liquid acid in the liquid acid supply tank to the high-pressure reaction kettle by means of the acid feeding pipeline; the pressurizers are arranged on the acid feeding pipeline and used for dynamically containing or discharging the liquid acid so as to reduce pressure fluctuation in the acid feeding pipeline. Pressurizers are arranged on the acid feeding pipeline, and the pressurizers can contain part of the liquid acid when the pressure in the acid feeding pipeline is too high so as to decrease the pressure of the acid feeding pipeline, or discharge part of the liquid acid when the pressure in the acid feeding pipeline is too low so as to increase the pressure of the acid feeding pipeline, thereby achieving the purpose of reducing pressure fluctuation in the acid feeding pipeline, keeping the pressure of the liquid acid in the acid feeding pipeline within a proper range, and improving the effect of acid leaching in the high-pressure reaction kettle.

Description

A high-pressure autoclave acid addition system for hydrometallurgy of laterite nickel ore Technical Field

[0001] The invention relates to the technical field of nickel ore processing, in particular to an autoclave acid addition system for hydrometallurgy of laterite nickel ore. Background Art

[0002] Laterite nickel ore is a loose, clay-like aggregate containing oxides of elements such as nickel, iron, magnesium, cobalt, silicon, and aluminum, formed through long-term geological processes such as weathering, leaching, dissemination, and alteration of nickel-bearing olivine bedrock in tropical or subtropical regions. The iron element is severely oxidized to a +3 valence state, giving it an overall reddish-brown appearance, hence the name laterite nickel ore. Unlike nickel sulfide ore, laterite nickel ore is a difficult-to-process oxide ore, making it difficult to effectively enrich nickel through beneficiation methods. Therefore, the current common treatment method for nickel extraction from laterite nickel ore is beneficiation, high-pressure acid leaching, and extraction.

[0003] During the high-pressure leaching process of laterite nickel ore, acid needs to be continuously added to the autoclave. Since the autoclave is in a high-pressure environment, the acid needs to be pressurized so that the pressure of the acid is greater than the pressure inside the autoclave, which facilitates the addition of the acid to the autoclave. For example, patent CNCN202210000475.5 provides an autoclave acid addition system and control method, which includes: an autoclave; an acid addition pipeline, one end of which is connected to the autoclave and the other end is connected to a pump to pump acid into the autoclave through the acid addition pipeline, wherein the acid addition pipeline is provided with a third valve and the third valve is close to the nozzle of the autoclave; a vent pipeline, connected to the acid addition pipeline, to pass the high-pressure gas in the vent pipeline into the acid addition pipeline; wherein the vent pipeline is provided with a second valve; the acid addition pipeline is provided with a first valve, and the first valve is located between the pump and the connection point between the vent pipeline and the acid addition pipeline.

[0004] However, there are the following problems: when the valve is opened and closed, the pressure of the acid liquid in the pipeline will fluctuate, which will affect the flow rate of the acid liquid.

[0005] Summary of the Invention

[0006] In view of this, the present invention provides an autoclave acid addition system for laterite nickel ore hydrometallurgy, which reduces pressure fluctuations in pipelines.

[0007] In order to achieve the above-mentioned purpose, the technical solution of the present invention to solve the technical problem is to provide a high-pressure autoclave acid addition system for wet smelting of laterite nickel ore, comprising: an acid supply tank, an acid addition pipeline, an acid addition pump, a pressure stabilizer and a high-pressure reactor, one end of the acid addition pipeline is connected to the high-pressure reactor, and the other end is connected to the acid supply tank; the acid addition pump is arranged on the acid addition pipeline, and is used to pressure-pump the acid in the acid supply tank to the high-pressure reactor through the acid addition pipeline; the pressure stabilizer is arranged on the acid addition pipeline, and is used to dynamically accommodate or discharge the acid to reduce pressure fluctuations in the acid addition pipeline.

[0008] Furthermore, the method comprises two voltage stabilizers, which are respectively arranged at the inlet of the acid adding pump and the outlet of the acid adding pump.

[0009] Furthermore, the pressure stabilizer includes a pressure stabilizing tank and a pressure supply device, one end of the pressure stabilizing tank is connected to the pressure supply device, and the other end of the pressure stabilizing tank is connected to the acid adding pipeline. A flexible membrane is provided in the middle of the pressure stabilizing tank to separate the inside of the pressure stabilizing tank into an acid liquid containing space connected to the acid adding pipeline and a pressure stabilizing space connected to the pressure supply device. The pressure supply device makes the pressure in the pressure stabilizing space reach a set range.

[0010] Furthermore, a supply valve is provided on one end of the acid adding pipeline close to the acid solution supply tank, and a discharge valve is provided on one end close to the high-pressure reactor.

[0011] Furthermore, it also includes a reflux pipe, one end of which is connected to the acid addition pipe between the acid addition pump and the high-pressure reactor, and the other end of the reflux pipe is connected to the acid supply tank, and a reflux valve is provided at the connection point between the acid addition pipe and the reflux pipe.

[0012] Furthermore, it also includes a gas supply device, which is connected to the acid addition pipeline and is used to supply gas that meets a preset pressure into the acid addition pipeline when the acid supply is stopped, so that the remaining acid liquid in the acid addition pipeline can be sent into the high-pressure reactor at an appropriate pressure.

[0013] Furthermore, the acid adding pipeline is provided with an anti-backflow valve, and the anti-backflow valve is located between the connection between the acid adding pump and the acid adding pipeline and the connection between the air compression pump and the acid adding pipeline.

[0014] Furthermore, a pressure gauge is provided on the acid adding pipeline for detecting the pressure in the acid adding pipeline.

[0015] Furthermore, a flow meter is provided on the acid adding pipeline for detecting the flow of the acid liquid in the acid adding pipeline.

[0016] Furthermore, the inner wall of the high-pressure reactor is coated with a titanium alloy layer.

[0017] Compared with the prior art, the autoclave acid addition system and method for hydrometallurgy of laterite nickel ore provided by the present invention have the following beneficial effects:

[0018] Compared with the prior art, the present invention is characterized in that the pressure stabilizer is arranged on the acid addition pipeline. The pressure stabilizer can accommodate part of the acid liquid to reduce the pressure of the acid addition pipeline when the pressure in the acid addition pipeline is too high, or discharge part of the acid liquid to increase the pressure of the acid addition pipeline when the pressure in the acid addition pipeline is too low, thereby achieving the purpose of reducing the pressure fluctuation in the acid addition pipeline, maintaining the pressure of the acid liquid in the acid addition pipeline within an appropriate range, and helping to improve the effect of acid leaching in the high-pressure reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG1 is a schematic diagram of an autoclave acid addition system for hydrometallurgy of laterite nickel ore provided by the present invention;

[0020] In the figure: 1-acid supply tank, 2-acid addition pipeline, 21-supply valve, 22-discharge valve, 23-reflux valve, 24-anti-backflow valve, 25-pressure gauge, 26-flow meter, 3-acid addition pump, 4-pressure stabilizer, 5-high-pressure reactor, 6-reflux pipeline, 7-gas supply device. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] Referring to Figure 1, the present invention provides an autoclave acid addition system for hydrometallurgical smelting of laterite nickel ore, comprising: an acid supply tank 1, an acid addition pipeline 2, an acid addition pump 3, a pressurizer 4, and a high-pressure reactor 5. One end of the acid addition pipeline 2 is connected to the high-pressure reactor 5, and the other end is connected to the acid supply tank 1. The acid addition pump 3 is provided on the acid addition pipeline 2 and is used to pressure-pump the acid in the acid supply tank 1 to the high-pressure reactor 5 through the acid addition pipeline 2. The pressurizer 4 is provided on the acid addition pipeline 2 and is used to dynamically accommodate or discharge the acid to reduce pressure fluctuations in the acid addition pipeline 2.

[0023] Compared with the prior art, the present invention is characterized in that the pressure stabilizer 4 is provided on the acid addition pipeline 2. The pressure stabilizer 4 can accommodate part of the acid liquid to reduce the pressure of the acid addition pipeline 2 when the pressure in the acid addition pipeline 2 is too high, or discharge part of the acid liquid to increase the pressure of the acid addition pipeline 2 when the pressure in the acid addition pipeline 2 is too low, thereby achieving the purpose of reducing the pressure fluctuation in the acid addition pipeline 2, maintaining the pressure of the acid liquid in the acid addition pipeline 2 within an appropriate range, and helping to improve the effect of acid leaching in the high-pressure reactor 5.

[0024] Specifically, the acid solution supply tank 1 stores acid solution for pickling treatment.

[0025] Specifically, the acid adding pipe 2 is provided with a supply valve 21 on one end close to the acid liquid supply tank 1, and a discharge valve 22 on one end close to the high pressure reactor 5. The supply of the acid liquid can be interrupted by closing the supply valve 21 and the discharge valve 22.

[0026] Specifically, the acid addition pump 3 has the ability to pump under pressure, and can pump out the acid solution under pressure. Generally speaking, the internal pressure range of the autoclave 5 is generally 1.5-5 MPa. To ensure smooth delivery of the acid solution, the pressure of the acid solution must be 0.1-0.3 MPa greater than the internal pressure of the autoclave 5.

[0027] Specifically, the pressure stabilizer 4 includes a pressure stabilizing tank and a pressure supply device. One end of the pressure stabilizing tank is connected to the pressure supply device, and the other end of the pressure stabilizing tank is connected to the acid adding pipeline 2. A flexible membrane is provided in the middle of the pressure stabilizing tank to separate the pressure stabilizing tank into an acid liquid containing space connected to the acid adding pipeline 2 and a pressure stabilizing space connected to the pressure supply device. The pressure supply device makes the pressure in the pressure stabilizing space reach a set range. During use, the air pressure in the pressure stabilization space is made the same as the preset acid liquid pumping pressure; when the pressure in the acid adding pipeline 2 is too high, the pressure in the acid liquid holding space increases, so that the flexible membrane is deformed toward the pressure stabilization space, the space of the acid liquid holding space increases, and more acid liquid is held, thereby reducing the pressure in the acid adding pipeline 2; when the pressure in the acid adding pipeline 2 is too low, the pressure in the acid liquid holding space decreases, and the air pressure in the pressure stabilization space drives the flexible membrane to deform toward the acid liquid holding space, the space of the acid liquid holding space decreases, and the acid liquid in the acid liquid holding space is discharged into the acid adding pipeline 2, thereby increasing the pressure in the acid adding pipeline 2.

[0028] In this embodiment, the pressure supply device is an air pump.

[0029] Furthermore, the two pressure stabilizers 4 are provided, respectively disposed at the inlet of the acid addition pump 3 and the outlet of the acid addition pump 3 .

[0030] Specifically, the inner wall of the high-pressure reactor 5 is coated with a titanium alloy layer, which can provide corrosion resistance and extend the service life.

[0031] Specifically, it also includes a reflux pipe 6, one end of which is connected to the acid addition pipe 2 between the acid addition pump 3 and the high-pressure reactor 5, and the other end of the reflux pipe 6 is connected to the acid solution supply tank 1. A reflux valve 23 is provided at the connection between the acid addition pipe 2 and the reflux pipe 6. The purpose of providing the reflux pipe 6 is to achieve cyclic pressurization in the initial stage of acid addition. During pressurization, the reflux valve 23 and the discharge valve 22 are closed, and the acid discharged from the acid addition pump 3 can only flow back into the acid solution supply tank 1 through the reflux pipe 6. The acid addition pump 3 gradually pressurizes the acid solution until the pressure reaches a preset value. At this time, the reflux valve 23 and the discharge valve 22 are opened again, and the acid solution that meets the pressure requirements is fed into the high-pressure reactor 5 through the acid addition pipe 2. This reflux pipe design can eliminate the setting of the sulfuric acid feed start-up pump and simplify the acid supply and stable acid supply system.

[0032] Specifically, it also includes a gas supply device 7, which is connected to the acid addition pipeline 2 and is used to supply gas that meets a preset pressure into the acid addition pipeline 2 when the acid supply is stopped, so that the remaining acid liquid in the acid addition pipeline 2 can be sent into the high-pressure reactor 5 at an appropriate pressure.

[0033] In this embodiment, the air supply device is a high-pressure air compressor.

[0034] Furthermore, a backflow prevention valve 24 is provided on the acid addition pipeline 2, and the backflow prevention valve 24 is located between the connection between the acid addition pump 3 and the acid addition pipeline 2 and the connection between the air compression pump 7 and the acid addition pipeline 2. When the acid supply is stopped, the backflow prevention valve 24 is closed. The backflow prevention valve can prevent the acid in the acid addition pipeline 2 from flowing back toward the acid addition pump 3 under the drive of the high-pressure gas of the air compression pump 7, thereby protecting the acid addition pump 3.

[0035] Furthermore, a pressure gauge 25 is provided on the acid adding pipeline 2 for detecting the pressure in the acid adding pipeline 2 .

[0036] Furthermore, a flow meter 26 is provided on the acid adding pipeline 2 for detecting the flow rate of the acid solution in the acid adding pipeline 2 .

[0037] When in use, the acid solution must be pressurized first, and the reflux valve 23 and the discharge valve 22 are closed. The acid solution discharged by the acid adding pump 3 can only flow back into the acid solution supply tank 1 through the reflux pipe 6. The acid adding pump 3 gradually pressurizes the acid solution until the pressure reaches a preset value. At this time, the reflux valve 23 and the discharge valve 22 are opened again, and the acid solution that meets the pressure requirements is sent into the high-pressure reactor 5 through the acid adding pipe 2. Pressure fluctuations may occur during the supply of acid solution. When the pressure in the acid adding pipe 2 is too high, the pressure in the acid solution holding space increases, so that the flexible membrane deforms toward the pressure stabilizing space, and the space of the acid solution holding space increases to accommodate more acid solution, thereby reducing the pressure in the acid adding pipe 2. When the pressure in the pipeline 2 is too low, the pressure in the acid liquid holding space decreases, and the air pressure in the pressure stabilization space drives the flexible membrane to deform toward the acid liquid holding space. The space of the acid liquid holding space decreases, and the acid in the acid liquid holding space is discharged into the acid adding pipeline 2, thereby increasing the pressure in the acid adding pipeline 2, and the stabilizer 4 can reduce the pressure fluctuation amplitude; when the acid supply is stopped, the anti-backflow valve 24 is closed, and the air compression pump 7 supplies high-pressure gas to the acid adding pipeline 2, so that the remaining acid in the acid adding pipeline 2 is sent into the high-pressure reactor 5 at an appropriate pressure. The anti-backflow valve 24 prevents the acid in the acid adding pipeline 2 from flowing back to the acid adding pump 3 driven by the high-pressure gas of the air compression pump 7, thereby protecting the acid adding pump 3.

[0038] Compared with the prior art, the present invention has the following advantages:

[0039] Compared with the prior art, the present invention is characterized in that the pressure stabilizer is arranged on the acid addition pipeline. The pressure stabilizer can accommodate part of the acid liquid to reduce the pressure of the acid addition pipeline when the pressure in the acid addition pipeline is too high, or discharge part of the acid liquid to increase the pressure of the acid addition pipeline when the pressure in the acid addition pipeline is too low, thereby achieving the purpose of reducing the pressure fluctuation in the acid addition pipeline, maintaining the pressure of the acid liquid in the acid addition pipeline within an appropriate range, and helping to improve the effect of acid leaching in the high-pressure reactor.

[0040] The specific embodiments of the present invention described above do not limit the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the present invention.

Claims

1. An autoclave acid adding system for laterite nickel ore hydrometallurgy, characterized in that: include: An acid liquid supply tank, an acid adding pipeline, an acid adding pump, a pressure stabilizer and a high-pressure reactor, wherein one end of the acid adding pipeline is connected to the high-pressure reactor, and the other end is connected to the acid liquid supply tank; the acid adding pump is arranged on the acid adding pipeline, and is used to pump the acid liquid in the acid liquid supply tank to the high-pressure reactor through the acid adding pipeline; the pressure stabilizer is arranged on the acid adding pipeline, and is used to dynamically contain or discharge the acid liquid to reduce the pressure fluctuation in the acid adding pipeline.

2. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 1, characterized in that: It comprises two voltage stabilizers, which are respectively arranged at the inlet of the acid adding pump and the outlet of the acid adding pump.

3. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 1, characterized in that: The pressure stabilizer includes a pressure stabilizing tank and a pressure supply device, one end of the pressure stabilizing tank is connected to the pressure supply device, and the other end of the pressure stabilizing tank is connected to the acid adding pipeline. A flexible membrane is arranged in the middle of the pressure stabilizing tank to separate the inside of the pressure stabilizing tank into an acid liquid containing space connected to the acid adding pipeline and a pressure stabilizing space connected to the pressure supply device. The pressure supply device makes the pressure in the pressure stabilizing space reach a set range.

4. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 1, characterized in that: A supply valve is provided on one end of the acid adding pipeline close to the acid liquid supply tank, and a discharge valve is provided on one end of the acid adding pipeline close to the high pressure reactor.

5. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 4, characterized in that: It also includes a reflux pipeline, one end of which is connected to the acid adding pipeline between the acid adding pump and the high-pressure reactor, and the other end of which is connected to the acid supply tank. A reflux valve is provided at the connection between the acid adding pipeline and the reflux pipeline.

6. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 4, characterized in that: It also includes a gas supply device, which is connected to the acid adding pipeline and is used to supply gas that meets a preset pressure into the acid adding pipeline when the acid supply is stopped, so that the remaining acid liquid in the acid adding pipeline can be sent into the high-pressure reactor at an appropriate pressure.

7. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 6, characterized in that: The acid adding pipeline is provided with an anti-backflow valve, and the anti-backflow valve is located between the connection between the acid adding pump and the acid adding pipeline and the connection between the air compression pump and the acid adding pipeline.

8. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 1, characterized in that: The acid adding pipeline is provided with a pressure gauge for detecting the pressure in the acid adding pipeline.

9. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 1, characterized in that: The acid adding pipeline is provided with a flow meter for detecting the flow of the acid liquid in the acid adding pipeline.

10. The autoclave acid addition system for laterite nickel ore hydrometallurgy according to claim 1, characterized in that: The inner wall of the high-pressure reactor is coated with a titanium alloy layer.

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