Multi-stage countercurrent washing system for hydrometallurgical processing of laterite nickel ore

Abstract

Provided in a technical solution of the present invention is a multi-stage countercurrent washing system for the hydrometallurgical processing of a laterite nickel ore. The multi-stage countercurrent washing system comprises a plurality of stages of washing devices, overflow pipes and buffer tanks, wherein each buffer tank is arranged on the corresponding washing device, is connected to an overflow area of the washing device at the next stage by means of the overflow pipe, and is connected to a discharging pipe at the previous stage; an end of each overflow pipe that is connected to the corresponding buffer tank is located on an outer periphery of said buffer tank; and an end of each discharging pipe that is connected to the corresponding buffer tank is located at the top of said buffer tank to form a countercurrent between a slag phase and a washing liquid. In the present invention, by means of the buffer tanks, slag washing water at the next stage and the slag phase at the previous stage form a countercurrent, and primary first-stage solid-liquid impact-based separation is created, such that the washing liquid and materials are fully impacted. By means of a liquid injection pipe, the slag phase and the slag washing water which are impacted and mixed in a buffer pipe are injected from a position below a liquid level of the washing devices, and the slag phase in the washing devices is subjected to second-stage solid-liquid impact-based separation, such that the solid-liquid separation effect is improved.

Description

A multi-stage countercurrent washing system for laterite nickel ore hydrometallurgy Technical Field

[0001] The invention relates to the technical field of CCD countercurrent washing, in particular to a laterite nickel ore hydrometallurgy multi-stage countercurrent washing system. Background Art

[0002] In the hydrometallurgical production of laterite nickel ore, the process includes ore blending, ore washing, ore dressing, pressure or oxygen pressure leaching, cyclic leaching and neutralization, countercurrent washing, and multi-stage iron, aluminum and chromium removal. CCD countercurrent washing uses clean water or industrial return water to wash out the attached liquid from the residue obtained during the liquid-solid separation process, which is an important step in recovering the slag phase.

[0003] In the existing countercurrent washing method, multiple stages of washing devices are commonly connected in sequence. After the washing device of the last stage washes, the overflowed slag washing water is used as the washing water for the washing device of the previous stage. For example, CN101629238B describes a slag washing method in cobalt hydrometallurgy, in which the filter residue is countercurrently washed with a multi-stage washing device. The washing devices of each stage in the multi-stage washing device are connected in parallel and then in series with the filter press. The washing devices of each stage work in sequence. The slag washing water obtained after washing by the last stage of the washing device is used as the washing water for the washing device of the previous stage. The last stage of the washing device is washed with new water, and the slag washing water obtained by the first stage of the washing device is pumped into a slag washing water intermediate tank, and then the slag washing water in the slag washing water intermediate tank is pumped into a slag washing water storage tank.

[0004] However, the working principle of CCD countercurrent washing is to separate the solid phase and the liquid phase by utilizing the difference in specific gravity of the solid phase during the solid-liquid separation process and the impact force of the washing liquid on the material. In the wet smelting of laterite nickel ore, the overflow water (the slag washing water obtained after washing in the last stage washing device) is directly injected upward into the countercurrent washing device with the slag phase, which is prone to overflow turbidity and carries the slag phase to the previous stage. In addition, there is insufficient impact between the washing liquid and the material, which affects the efficiency of CCD countercurrent washing.

[0005] Summary of the Invention

[0006] In view of this, it is necessary to provide a multi-stage countercurrent washing system for laterite nickel ore hydrometallurgy to solve the technical problems in the existing technology that overflow is prone to occur, turbidity is carried to the previous stage, and there is insufficient impact between the washing liquid and the material, which affects the efficiency of CCD countercurrent washing.

[0007] In order to achieve the above technical objectives, the technical solution of the present invention provides a laterite nickel ore hydrometallurgical multi-stage countercurrent washing system, comprising:

[0008] Several stages of washing devices, each of which has an overflow area at the top and a slag phase discharge pipe at the bottom, and the washing liquid is injected into the lowest stage of the washing device;

[0009] An overflow pipe connected between two adjacent stages of the washing devices, used to transport the slag washing water overflowing from the overflow area of ​​the current stage to the upper stage, so that the slag washing water of the uppermost stage of the washing device overflows from the overflow area; and

[0010] A buffer tank is correspondingly arranged on the washing device and is connected to the overflow area of ​​the washing device of the next level and to the discharge pipe of the previous level through the overflow pipe, wherein the connection end of the overflow pipe and the buffer tank is located at the periphery of the buffer tank, and the connection end of the discharge pipe and the buffer tank is located at the top of the buffer tank, forming a hedge between the slag phase and the washing liquid. An injection pipe is provided at the bottom of the buffer tank, and the bottom end of the injection pipe is connected to the outside of the washing device and injected from below the liquid surface layer of the washing device.

[0011] Furthermore, the interior of the washing device is divided into an overflow area, a separation area and a sedimentation area from top to bottom. The connection position between the injection pipe and the washing device is located in the separation area of ​​the washing device, forming an impact on the slag phase in the separation area.

[0012] Furthermore, a stirring mechanism is provided inside the washing device for stirring inside the washing device.

[0013] Furthermore, the buffer tank is located above the liquid level of the washing device, and both the washing device and the buffer tank are connected to the atmosphere.

[0014] Furthermore, several branch pipes are provided between the overflow pipe and the buffer tank and between the injection pipe and the washing device. The injection pipe is connected to the washing device through the branch pipes, and the overflow pipe is connected to the buffer tank through the branch pipes, and several branch pipes are distributed in a circular shape on the outside of the buffer tank and the washing device, wherein the branch pipes on the buffer tank also have an elevation angle.

[0015] Furthermore, the uppermost washing device is provided with a muddy water warning mechanism for warning of muddy overflow water in the overflow area.

[0016] Furthermore, the muddy water warning mechanism includes a connecting pipe, a storage tank and a conveying assembly. The connecting pipe is connected to below the liquid level in the washing device, and the other end of the connecting pipe is lower than the liquid level of the washing device and is connected to the atmosphere. The storage tank is arranged directly below the other end of the connecting pipe to receive the liquid flowing out thereof. One end of the conveying assembly is connected to the storage tank, and the other end is suspended on the overflow area to return the liquid in the storage tank to the overflow area.

[0017] Furthermore, the conveying assembly includes a pump body and a return pipe, the pump body is arranged on the return pipe, one end of the return pipe is connected to the storage tank, and the other end is suspended on the overflow area.

[0018] Furthermore, the turbidity warning mechanism also includes a turbidity detector, which is arranged on the storage tank and is used to detect the turbidity of the liquid in the storage tank.

[0019] Furthermore, the turbidity warning mechanism also includes a camera for photographing the color of the liquid discharged from the other end of the connecting tube.

[0020] Compared with the prior art, the present invention has the following beneficial effects: the slag washing water of the next stage is offset against the slag phase of the previous stage through the buffer tank, forming a front first-level solid-liquid impact separation, so that the washing liquid and the material are fully impacted, and the slag phase and slag washing water impacted and mixed in the buffer tube are injected from below the liquid surface of the washing device through the injection pipe, and the slag phase in the washing device is subjected to a second level of solid-liquid impact separation, thereby improving the effect of solid-liquid separation, and, by injecting from the liquid surface to the bottom, impact turbidity on the liquid surface is avoided, the probability of overflow turbidity is reduced, and the slag phase is avoided from being carried to the previous stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG1 is a schematic structural diagram of a multi-stage countercurrent washing system for laterite nickel ore hydrometallurgy according to an embodiment of the present invention;

[0022] FIG2 is a partial enlarged view of a multi-stage countercurrent washing system for laterite nickel ore hydrometallurgy according to an embodiment of the present invention;

[0023] 3 is a schematic structural diagram of branch pipes of a multi-stage countercurrent washing system for laterite nickel ore hydrometallurgy according to an embodiment of the present invention;

[0024] In the figure: 1, washing device; 101, overflow area; 102, discharge pipe; 103, stirring mechanism; 11, overflow area; 12, separation area; 13, sedimentation area;

[0025] 2. Overflow pipe;

[0026] 3. Buffer tank; 301. Liquid injection pipe; 302. Branch pipe;

[0027] 4. Turbidity warning mechanism; 41. Connecting pipe; 42. Storage tank; 43. Conveying assembly; 44. Turbidity detector; 45. Camera; 431. Pump body; 432. Return pipe. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0029] As shown in Figures 1-3, the present invention provides a multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore, comprising several stages of washing devices 1, an overflow pipe 2 and a buffer tank 3, wherein the top of the washing device 1 is provided with an overflow area 101, and the bottom thereof is provided with a slag phase discharge pipe 102, the washing liquid is injected into the washing device 1 of the lowest stage, and the slag phase is washed from the washing device 1 of the lowest stage, thereby forming slag washing water, which overflows upward and flows into the washing device 1 of the upper stage through the overflow pipe 2, and is used as the washing liquid of the washing device 1 of the upper stage; the overflow pipe 2 is connected between the two adjacent stages of the washing devices 1, and is used to transport the slag washing water overflowing from the overflow area 101 of this stage to the upper stage, and the slag washing water of the washing device 1 of the upper stage overflows from the overflow area 101; the buffer tank 3 is correspondingly arranged on the washing device 1, and is connected to the overflow area 101 of the washing device 1 of the lower stage through the overflow pipe 2, and the buffer tank 3 is connected to the discharge pipe 102 of the upper stage, wherein the overflow pipe 2 and the buffer tank 3 are located on the periphery of the buffer tank 3, and the connection end of the discharge pipe 102 and the buffer tank 3 is located at the top of the buffer tank 3, forming a counterattack between the slag phase and the washing liquid, and performing the first solid-liquid impact separation placed outside the washing device 1. The bottom of the buffer tank 3 is provided with an injection pipe 301, and the bottom end of the injection pipe 301 is connected to the outside of the washing device 1. It is injected from below the liquid surface layer of the washing device 1 to impact the slag phase that is in the solid-liquid separation below the liquid surface layer, forming a second solid-liquid impact separation, thereby forming a two-layer solid-liquid impact separation before the solid-liquid separation effect of the washing device 1 itself, and is injected below the liquid surface layer to avoid turbidity at the liquid surface position, reduce the probability of turbidity, and fully impact the washing liquid and the material, with a good washing effect.

[0030] It can be understood that a stirring mechanism 103 is provided on the inner side of the washing device 1 for stirring inside the washing device 1 to form a third solid-liquid impact separation, which, together with the first two solid-liquid impact separations, improves the efficiency of solid-liquid separation in the entire laterite nickel ore hydrometallurgical multi-stage countercurrent washing system. In addition, the washing device 1 can adopt a thickener, which itself has a stirring mechanism 103.

[0031] In this embodiment, in order to have the best impact effect when the injection pipe 301 is injected into the interior of the washing device 1 and avoid the generation of turbidity on the liquid surface, it is known that the interior of the washing device 1 is divided into an overflow area 11, a separation area 12 and a sedimentation area 13 from top to bottom. The overflow area 11 is relatively clear overflow slag washing water, and the separation area 12 is a stratification area for solid-liquid separation under stirring, solid-liquid separation, and the slag phase settles. The sedimentation area 13 is mostly the settled slag phase, which is transported downward to the next level of the washing device 1, wherein the connection position of the injection pipe 301 and the washing device 1 is located in the separation area 12 of the washing device 1, and the slag phase is in the solid-liquid separation position. Impact is performed on the slag phase in the separation area 12, thereby promoting solid-liquid separation, and because the impact position is far away from the liquid surface, the turbidity generated by the impact is avoided from overflowing from the liquid surface, which not only improves the solid-liquid separation efficiency of the washing, but also avoids the turbidity brought out by the impact.

[0032] Furthermore, in order to utilize atmospheric pressure to automatically press in the washing liquid, the communicating vessel principle is adopted. The height position of the buffer tank 3 is located above the liquid level of the washing device 1, and the washing device 1 and the buffer tank 3 are both connected to the atmosphere. The atmospheric pressure is utilized to press the slag washing water in the buffer tank 3 located at a high position into the washing device 1.

[0033] Furthermore, in order to form a more comprehensive impact effect, several branch pipes 302 are provided between the overflow pipe and the buffer tank 3 and between the injection pipe 301 and the washing device 1. The injection pipe 301 is connected to the washing device 1 through the branch pipe 302, and the overflow pipe is connected to the buffer tank 3 through the branch pipe 302, and several branch pipes 302 are distributed in a circular pattern on the outside of the buffer tank 3 and the washing device 1 to form a uniform impact. Among them, the branch pipe 302 on the buffer tank 3 also has an elevation angle, which has a counter-elevation angle, and has an upward impact effect on the slag phase, promoting the upward flushing and separation of the washing liquid, and more sufficient impact on the slag phase.

[0034] It can be understood that the branch pipe 302 between the corresponding injection pipe 301 and the washing device 1 can be horizontally injected to break up the slag phase and promote separation.

[0035] In a certain embodiment, due to the multi-stage countercurrent washing, the slag washing water is finally used for the slag washing in the upper stage, and the impact of turbidity in between is not significant, and it will eventually be separated by subsequent washing. However, if the top-level washing device 1 becomes turbid, it is difficult to reuse it. Therefore, in order to warn of turbidity of the top-level washing device 1 and provide sufficient time for manual intervention, a turbidity warning mechanism 4 is provided on the top-level washing device 1 for warning of turbidity of overflow water in the overflow area 101.

[0036] Furthermore, in order to facilitate the staff to monitor turbidity and provide intervention time before turbidity occurs, the turbidity warning mechanism 4 includes a connecting pipe 41, a storage tank 42 and a conveying component 43. The connecting pipe 41 is connected to below the liquid level in the washing device 1, monitors the turbidity of the liquid below the liquid level, and issues an early warning when it has not overflowed to the liquid level, thereby providing sufficient intervention time. The other end of the connecting pipe 41 is lower than the liquid level of the washing device 1 and is connected to the atmosphere. The pressure difference is used to press the liquid at this position outward, and the storage tank 42 is arranged directly below the other end of the connecting pipe 41 to receive the liquid flowing out. By observing the pressed liquid, it can be known whether the slag washing water at this depth has become turbid. One end of the conveying component 43 is connected to the storage tank 42, and the other end is suspended on the overflow area 101, for returning the liquid in the storage tank 42 to the overflow area 101, and reusing the slag washing water used for early warning.

[0037] Furthermore, the conveying component 43 includes a pump body 431 and a return pipe 432. The pump body 431 is arranged on the return pipe 432. One end of the return pipe 432 is connected to the storage tank 42, and the other end is suspended on the overflow area 101. The monitoring slag washing water in the storage tank 42 is extracted through the pump body 431 and the return pipe 432 and returned to the overflow area 101.

[0038] Optionally, in this embodiment, the turbidity warning mechanism 4 further includes a turbidity detector 44 . The turbidity detector 44 is disposed on the storage tank 42 and is used to detect the turbidity of the liquid in the storage tank 42 .

[0039] It can be understood that the turbidity detector 44 can monitor the turbidity of the liquid and provide a timely warning when turbidity occurs.

[0040] Optionally, in this embodiment, the turbidity warning mechanism 4 further includes a camera 45 for photographing the color of the liquid discharged from the other end of the connecting tube 41 .

[0041] It can be understood that the camera 45 can capture the image of the liquid and determine whether the liquid is turbid based on the image. When the liquid in the image is found to be turbid, it has an early warning effect.

[0042] The specific working process of the present invention is as follows: the slag phase in the previous process is transported to the first-stage washing position, and in the buffer tank 3, it is offset against the slag washing water of the next stage, forming a first separation impact, and branching downward from the injection pipe 301, and injected into the separation area 12 of the washing device 1 of this stage through the branch pipe 302, forming a second separation impact on the slag phase therein, and then cooperating with the stirring mechanism 103 in the washing device 1 to perform a third separation impact, with the triple separation impact, forming an efficient solid-liquid separation of the slag phase at each washing position; at the top and bottom washing positions, the washing device 1 is given a turbidity warning mechanism 4 to provide a turbidity warning, and the slag washing water below the liquid surface is continuously extracted for observation, and the turbidity is monitored in cooperation with the camera 45 or the turbidity detector 44, so that turbidity can be discovered in time when the liquid layer below the liquid surface becomes turbid, and there is sufficient time for manual intervention before it expands above the liquid surface.

[0043] The entire workflow is complete, and all contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0044] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore, characterized in that, it includes: Several washing devices, an overflow area is arranged at the top of the washing device, a slag phase discharge pipe is arranged at the bottom thereof, and the lowest-stage washing device injects washing liquid; An overflow pipe, which is connected between two adjacent washing devices, is used to convey the slag-washing water overflowing from the overflow area of the current stage to the upper stage, and the slag-washing water of the uppermost-stage washing device overflows from the overflow area; and A buffer tank, which is correspondingly arranged on the washing device, is connected to the overflow area of the next-stage washing device through the overflow pipe, and is connected to the discharge pipe of the upper stage. Among them, the connection end of the overflow pipe and the buffer tank is located on the outer periphery of the buffer tank, and the connection end of the discharge pipe and the buffer tank is located at the top of the buffer tank, forming a counterflush between the slag phase and the washing liquid. A liquid injection pipe is arranged at the bottom of the buffer tank, and the bottom end of the liquid injection pipe is connected to the outside of the washing device and is injected from below the liquid surface layer of the washing device.

2. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 1, characterized in that, Inside the washing device, it is successively divided into an overflow area, a separation area and a precipitation area from top to bottom. The connection position of the liquid injection pipe and the washing device is located in the separation area of the washing device, forming an impact on the slag phase in the separation area.

3. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 2, characterized in that, A stirring mechanism is arranged on the inner side of the washing device for stirring inside it.

4. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 3, characterized in that, The height position of the buffer tank is above the liquid surface height of the washing device, and both the washing device and the buffer tank are communicated with the atmosphere.

5. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 4, characterized in that, Several branch pipes are arranged between the overflow pipe and the buffer tank and between the liquid injection pipe and the washing device. The liquid injection pipe is communicated with the washing device through the branch pipes, and the overflow pipe is communicated with the buffer tank through the branch pipes. And several branch pipes are circumferentially distributed on the outer sides of the buffer tank and the washing device. Among them, the branch pipes on the buffer tank also have an elevation angle.

6. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 5, characterized in that, An anti-slurry-warning mechanism is arranged on the uppermost-stage washing device for warning against slurry running in the overflow water of the overflow area.

7. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 6, characterized in that, The muddy water running warning mechanism includes a connecting pipe, a storage tank, and a conveying component. The connecting pipe is connected below the liquid level in the washing device. The other end of the connecting pipe is lower than the liquid level height of the washing device and is communicated with the atmosphere. The storage tank is arranged directly below the other end of the connecting pipe to receive the liquid flowing out of it. One end of the conveying component is connected to the storage tank, and the other end is suspended above the overflow area to return the liquid in the storage tank to the overflow area.

8. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 7, characterized in that the conveying component includes a pump body and a reflux pipeline. The pump body is arranged on the reflux pipeline. One end of the reflux pipeline is connected to the storage tank, and the other end is suspended above the overflow area.

9. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 8, characterized in that the muddy water running warning mechanism further includes a turbidity detector arranged on the storage tank for detecting the turbidity of the liquid in the storage tank.

10. The multi-stage countercurrent washing system for hydrometallurgy of laterite nickel ore according to claim 8, characterized in that the muddy water running warning mechanism further includes a camera for photographing the color of the liquid discharged from the other end of the connecting pipe.

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