Nickel plating solution on-line monitoring system and method

Abstract

The application provides a nickel solution preparation on-line monitoring system and method, and belongs to the technical field of non-ferrous hydrometallurgy; the system comprises a waste liquid receiving tank, an acid adjusting tank, a hydrogen ion on-line detection device and a controller; the hydrogen ion on-line detection device monitors the hydrogen ion concentration of a key area in real time; the controller automatically adjusts the adding amount of acid liquid and fresh water according to the detection signal, and controls the outlet flow in linkage, so that full-automatic acid adjusting and solution preparation are realized. The application can solve the problems of high labor intensity, low precision and poor safety of manual acid adjusting, realize accurate control of the hydrogen ion concentration, improve the qualified rate of acid adjusting, and thus improve the solution preparation efficiency and product quality.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal hydrometallurgy technology, and relates to an online monitoring system and method for nickel production. Background Technology

[0002] In electrolytic nickel production, the solution preparation process mainly uses various nickel solutions, wastewater, and waste acid as raw materials for electrolytic nickel replenishment, serving purposes such as copper removal, acid reduction, and balancing impurities in the system. Due to the complex composition and significant volume fluctuations of these solutions, solution preparation is challenging. Currently, some companies manually add acid and measure pH levels, requiring the addition of sulfuric acid or hydrochloric acid every two hours. This method suffers from problems such as excessive acid addition, nickel ion back-precipitation at the cathode, low low-acid outlet pass rate, high operating frequency, and low control precision. Furthermore, the manual control of valves for acid addition poses risks of burns and acid-related injuries.

[0003] Therefore, there is an urgent need for a system that can automatically adjust acid and prepare the solution, monitor it in real time, and control it precisely in the solution preparation process, so as to improve production efficiency, stabilize product quality, and reduce safety risks. Summary of the Invention

[0004] The purpose of this invention is to address the problems existing in the prior art by providing an online monitoring system for nickel production solutions, which solves the problems of excessive acid addition, cathode nickel ion back-precipitation, low low-acid outlet qualification rate, high operation frequency, and low control precision in the existing solution preparation process.

[0005] This invention enables automated acid adjustment and solution preparation in the solution-making process, reducing labor intensity for employees, improving production efficiency and safety, and ensuring stable product quality. To achieve the above objectives, this invention adopts the following technical solution: An online monitoring system for nickel production solution includes: Multiple waste liquid receiving tanks are used to receive nickel-containing solutions, wastewater, and waste acid; At least one acid-adjusting tank is connected to the waste liquid receiving tank; An online hydrogen ion detection device is installed at least one of the following: the outlet of the acid adjustment tank, the outlet of the high acid high-level tank, the inlet of the low acid liquid preparation tank, and the outlet of the low acid liquid preparation tank. The automatic control unit includes an automatic valve for the acid pipeline, an automatic valve for the fresh water pipeline, and a controller. The controller controls the opening and closing of the automatic valves for the acid pipeline and the fresh water pipeline based on the hydrogen ion concentration detection signal. The controller is connected to the online hydrogen ion detection device and is used to automatically adjust the amount of acid and / or fresh water added according to the hydrogen ion concentration detection signal to achieve automatic acid adjustment and solution preparation.

[0006] The system sets the hydrogen ion concentration control range as follows: when the detected value is below the lower limit, the acid valve is opened to add acid; when the detected value is above the upper limit, the new water valve is opened for dilution; when the detected value is within the normal range, all regulating valves are closed.

[0007] The system also has a flow regulating valve installed at the outlet of the low-acid liquid preparation tank, which automatically adjusts the outlet flow rate according to the outlet hydrogen ion concentration, forming a concentration-flow interlock control.

[0008] Specifically, the hydrogen ion online detection device uses at least two hydrogen ion online detection and analysis instruments arranged in parallel at the aforementioned monitoring points to achieve multi-point real-time monitoring.

[0009] Specifically, multiple waste liquid receiving tanks and acid adjusting tanks can be connected in parallel to improve the system's processing capacity and operational flexibility.

[0010] The present invention also provides an online monitoring method for nickel production solution using the above-described system, comprising: Real-time monitoring of hydrogen ion concentration at key locations; The monitoring signal is transmitted to the controller; The controller automatically adjusts the amount of acid or fresh water added based on the signal. The solution flow rate is automatically adjusted based on the outlet concentration.

[0011] Specifically, the control logic of the controller includes: When controlling the acidity of the solution in the acid adjustment tank: If the hydrogen ion concentration is lower than the first set threshold, the acid pipeline automatic valve is opened to add acid; if the hydrogen ion concentration is higher than the second set threshold, the fresh water pipeline automatic valve is opened to add fresh water; if the hydrogen ion concentration is between the first set threshold and the second set threshold, the acid pipeline automatic valve and the fresh water pipeline automatic valve are closed. When controlling the acidity of the solution in a low-acid solution preparation tank: When the hydrogen ion concentration is below the third set threshold, the opening of the automatic valve in the liquid outlet pipeline is increased; when the hydrogen ion concentration is equal to the third set threshold, the opening of the automatic valve in the liquid outlet pipeline remains unchanged; when the hydrogen ion concentration is above the third set threshold, the opening of the automatic valve in the liquid outlet pipeline is decreased.

[0012] The beneficial effects of this invention are as follows: 1. This invention introduces online detection and automatic feedback control of hydrogen ion concentration into the nickel production process to construct a complete monitoring system. Through the waste liquid receiving tank and acid adjustment tank group, the online detection points of hydrogen ions are reasonably arranged, and the detection signals are interlocked with the acid valve, water valve, and flow valve to form a complete closed-loop monitoring system from detection, judgment, execution to re-detection. This achieves fully automatic acid adjustment and solution preparation, replaces manual operation, reduces labor intensity, and eliminates human error and safety risks. 2. This invention enables fully automatic continuous operation, replacing manual operation. It not only significantly reduces labor intensity but also has an automatic and rapid response function, making solution preparation more timely, thereby shortening the preparation cycle, improving the overall solution preparation efficiency, effectively avoiding solution quality problems caused by cathode nickel ion back-precipitation and insufficient acid addition, and making the production process reliable. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the system structure of the present invention; Figure 2 This is a process flow diagram of the method of the present invention.

[0014] In the diagram, 1-waste liquid receiving tank, 1a-first receiving tank, 1b-second receiving tank, 1c-third receiving tank, 2-liquid addition pipeline, 2a-acid addition pipeline, 2b-water addition pipeline, 3-acid adjustment tank, 4-high acid high-level tank, 5-high acid liquid preparation tank, 6-low acid liquid preparation tank, 7-hydrogen ion online detection device, 8-controller, 8a-automatic valve for waste liquid pipeline, 8b-first flow meter, 8c-automatic valve for acid liquid pipeline, 8d-second flow meter, 8e-automatic valve for fresh water pipeline, 8f-third flow meter, 8g-automatic valve for liquid discharge pipeline, 8h-fourth flow meter, 9-flow pump. Detailed Implementation

[0015] The technical solution of the present invention will be described below with reference to the accompanying drawings and implementation methods.

[0016] Example 1 like Figure 1 As shown, an online monitoring system for nickel production solution includes: Waste liquid receiving tank 1 includes a first receiving tank 1a, a second receiving tank 1b and a third receiving tank 1c, which are used to receive nickel-containing solution, wastewater and waste acid respectively, and the three are arranged in parallel. The liquid addition line 2 includes an acid addition line 2a and a water addition line 2b, which are arranged in parallel; wherein, the acid addition line 2a includes a hydrochloric acid line or a sulfuric acid line. The acid-adjusting tank 3 has its inlet connected to the waste liquid receiving tank 1 and the liquid addition pipeline 2, and its outlet connected to the high-acid high-level tank 4. Specifically, the acid-adjusting tank 3 includes three parallel acid-adjusting sub-tanks 3a, 3b, and 3c, which are used to perform acid-adjusting operations alternately or simultaneously. Furthermore, the acid-adjusting tank 3 and the high-acid high-level tank 4 are connected by a flow pump 9.

[0017] High-acid high-level tank 4 is used to store intermediate solution after pre-adjustment of acidity, and its outlet is connected to high-acid liquid preparation tank 5. High acid solution preparation tank 5 is used to prepare high acid solution, and its outlet is connected to low acid solution preparation tank 6. Low-acid solution preparation tank 6 is used to prepare low-acid solutions and produce qualified anolytes; The hydrogen ion online detection device 7 is installed at the outlet of waste liquid receiving tank 1, the outlet of high acid high level tank 2, the outlet of high acid liquid preparation tank 5 and the outlet of low acid liquid preparation tank 6, respectively, and measures once every 30 minutes to accurately monitor the acidity of the solution.

[0018] Automatic control unit, including: The waste liquid pipeline automatic valve 8a and the first flow meter 8b are installed sequentially at the outlet of the waste liquid receiving tank 1 to control the amount of waste liquid added. An automatic valve 8c and a second flow meter 8d are installed sequentially at the outlet of the acid addition pipeline 2a to control the amount of acid added. The automatic valve 8e and the third flow meter 8f for the new water pipeline are installed sequentially at the outlet of the water supply pipeline 2b to control the amount of new water added. The automatic valve 8g and the fourth flow meter 8h are installed sequentially at the outlet of the low-acid liquid preparation tank 6 to control the liquid output. The controller 8 is electrically connected to the waste liquid pipeline automatic valve 8a, the acid liquid pipeline automatic valve 8c, and the fresh water pipeline automatic valve 8e, respectively.

[0019] like Figure 2 As shown, an online monitoring method for nickel production solution, applied to the above system, includes the following steps: The hydrogen ion concentration at at least one location is monitored in real time using the online hydrogen ion detection device 7. The monitoring signal is transmitted to controller 8; The controller 8 automatically adjusts the amount of acid and / or fresh water added based on the hydrogen ion concentration signal to achieve automatic acid adjustment and solution preparation.

[0020] Specifically, the control logic of controller 8 is as follows: The acidity of the solution in the acid adjustment tank 3 is interlocked with the automatic valve 8c of the acid supply pipeline and the automatic valve 8e of the fresh water pipeline. At this time, the acid addition pipeline 2a uses the hydrochloric acid pipeline. The technical requirement for the hydrogen ion concentration at the outlet of the acid adjustment tank 3 is 0.4~1.0g / L. When controlling the acidity of the solution in the acid adjustment tank 3: When the measured value of hydrogen ion concentration at the outlet of acid adjustment tank 3 is lower than 0.4 g / L, the automatic valve 8c of the acid pipeline is opened, and hydrochloric acid is evenly added to the first acid adjustment tank 3a, the second acid adjustment tank 3b and the third acid adjustment tank 3c. When the hydrogen ion concentration at the outlet of the high-acid high-level tank 4 exceeds 0.4 g / L, the automatic valve 8c of the acid pipeline closes, stopping the addition of acid. When the measured value of hydrogen ion concentration at the outlet of acidification tank 3 is higher than 1.0 g / L, the automatic valve 8e of the new water pipeline is opened, and new water is evenly added to the first acidification tank 3a, the second acidification tank 3b and the third acidification tank 3c. When the hydrogen ion concentration at the outlet of the high-acid high-level tank 4 is less than 1.0 g / L, the automatic valve 8e of the new water pipeline closes, stopping the water supply. When the measured value of hydrogen ion concentration at the outlet of acid adjusting tank 3 is in the range of 0.4 to 1.0 g / L, the automatic valve 8c of the acid pipeline and the automatic valve 8e of the fresh water pipeline are both in the closed state.

[0021] When controlling the acidity of the solution in the low-acid solution preparation tank 6: The hydrogen ion concentration of the mixed liquid in the low-acid liquid preparation tank 6 is interlocked with that of the fourth flow meter for 8 hours; the required hydrogen ion concentration at the outlet of the mixed liquid in the low-acid liquid preparation tank 6 is 0.08~0.20g / L; When the hydrogen ion concentration at the outlet of the low-acid liquid preparation tank 6 is lower than 0.08 g / L, the automatic valve 8g of the outlet pipeline is adjusted to control the flow rate to 20 m³ / h. When the hydrogen ion concentration at the outlet of the low-acid liquid preparation tank 6 is between 0.08 and 0.20 g / L, the automatic valve 8g in the outlet pipeline is adjusted to control the flow rate at 18 m³ / h. When the hydrogen ion concentration at the outlet of the low-acid liquid preparation tank 6 is higher than 0.20 g / L, the automatic valve 8g in the outlet pipeline is adjusted to control the flow rate to 16 m³ / h.

[0022] Example 2 The system in this embodiment has the same structure as that in Embodiment 1. The only difference is that when the controller 8 controls the acidity of the solution in the low-acid solution preparation tank 6, its control logic is as follows: The hydrogen ion concentration of the mixed liquid in the low-acid liquid preparation tank 6 is interlocked with that of the fourth flow meter 8h. The required hydrogen ion concentration at the outlet of the mixed liquid in the low-acid liquid preparation tank 6 is 0.09~0.21g / L.

[0023] When the hydrogen ion concentration at the outlet of the low-acid liquid preparation tank 6 is lower than 0.09 g / L, the automatic valve 8g in the outlet pipeline is adjusted to control the flow rate to 19 m³ / h. When the hydrogen ion concentration at the outlet of the low-acid liquid preparation tank is between 0.09 and 0.21 g / L, the automatic valve 8g in the outlet pipeline is adjusted to control the flow rate to 17 m³ / h. When the hydrogen ion concentration at the outlet of the low-acid liquid preparation tank is higher than 0.21 g / L, the automatic valve 8g in the outlet pipeline is adjusted to control the flow rate to 15 m³ / h.

[0024] As can be seen from the above embodiments, the method of the present invention, through online hydrogen ion detection and interlocking control of automatic valves, can realize fully automated acid adjustment and solution preparation in the solution preparation process, significantly improving the accuracy, stability and safety of process control.

Claims

1. An online monitoring system for nickel production solution, characterized in that, include: Waste liquid receiving tank (1) is used to receive nickel-containing solutions, wastewater and waste acid; The liquid addition line (2) includes an acid addition line (2a) and a water addition line (2b), which are arranged in parallel; The acid-adjusting tank (3) has its inlet connected to the waste liquid receiving tank (1) and the liquid adding pipeline (2) respectively, and its outlet connected to the high acid high-level tank (4); The high-acid high-level tank (4) is used to store the intermediate solution after the acidification process, and its outlet is connected to the high-acid liquid preparation tank (5). The high-acid solution preparation tank (5) is used to prepare high-acid solutions, and its outlet is connected to the low-acid solution preparation tank (6). Low-acid solution preparation tank (6) is used to prepare low-acid solutions and produce qualified anolytes; The hydrogen ion online detection device (7) is installed at least at the outlet of the waste liquid receiving tank (1), the outlet of the high acid high level tank (2), the outlet of the high acid liquid making tank (5), and the outlet of the low acid liquid making tank (6); Automatic control unit, including: An automatic valve (8a) and a first flow meter (8b) for waste liquid pipeline are installed sequentially at the outlet of the waste liquid receiving tank (1) to control the amount of waste liquid added. An automatic valve (8c) and a second flow meter (8d) are installed sequentially at the outlet of the acid addition line (2a) to control the amount of acid added. The automatic valve (8e) and the third flow meter (8f) for the new water pipeline are installed sequentially at the outlet of the water supply pipeline (2b) to control the amount of new water added. An automatic valve (8g) and a fourth flow meter (8h) are installed sequentially at the outlet of the low-acid liquid preparation tank (6) to control the liquid output. The controller (8) is electrically connected to the waste liquid pipeline automatic valve (8a), the acid liquid pipeline automatic valve (8c) and the fresh water pipeline automatic valve (8e), respectively.

2. The system according to claim 1, characterized in that, The acid addition line (2a) includes a hydrochloric acid line or a sulfuric acid line.

3. The system according to claim 1, characterized in that, The waste liquid receiving tank (1) includes at least a first receiving tank (1a), a second receiving tank (1b) and a third receiving tank (1c), which are used to receive nickel-containing solutions, wastewater and waste acid respectively, and are arranged in parallel.

4. The system according to claim 1, characterized in that, The acid conditioning tank (3) includes at least three acid conditioning sub-tanks arranged in parallel for alternating or simultaneous acid conditioning operations.

5. The system according to claim 1, characterized in that, The acid adjustment tank (3) and the high acid high level tank (4) are connected by a flow pump (9).

6. A method for online monitoring of nickel production solution, applied to the system described in any one of claims 1 to 5, characterized in that, include: The hydrogen ion concentration at at least one location is monitored in real time using an online hydrogen ion detection device (7); The monitoring signal is transmitted to the controller (8); The controller (8) automatically adjusts the amount of acid and / or new water added according to the hydrogen ion concentration signal to achieve automatic acid adjustment and solution preparation.

7. The method according to claim 6, characterized in that, The control logic of the controller (8) includes: When controlling the acidity of the solution in the acid adjustment tank (3): If the hydrogen ion concentration is lower than the first set threshold, open the automatic valve (8c) of the acid pipeline to add acid; If the hydrogen ion concentration is higher than the second set threshold, open the automatic valve (8e) of the new water pipeline to add new water; If the hydrogen ion concentration is between the first set threshold and the second set threshold, close the automatic valve (8c) of the acid pipeline and the automatic valve (8e) of the fresh water pipeline. When controlling the acidity of the solution in the low-acid solution preparation tank (6): When the hydrogen ion concentration is lower than the third set threshold, the opening degree of the automatic valve (8g) in the liquid outlet pipeline is increased. When the hydrogen ion concentration is equal to the third set threshold, the opening of the automatic valve (8g) in the liquid outlet pipeline is kept constant. When the hydrogen ion concentration is higher than the third set threshold, the opening degree of the automatic valve (8g) in the liquid outlet pipeline is reduced.

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