Automatic control device for leaching reaction of nickel-iron powder

Abstract

This invention discloses an automatic control device for nickel-iron powder leaching reaction, comprising a reaction assembly including a heated reaction tank, a nickel-iron powder slurry tank, an acid storage tank, and a control device. The heated reaction tank is equipped with a pH sensor, a temperature sensor, and an ORP detector. The nickel-iron powder slurry tank is connected to the inlet of the heated reaction tank. The acid storage tank is connected to the heated reaction tank via a first pipe and a second pipe. A coarse regulating valve is installed on the first pipe, and a fine regulating valve is installed on the second pipe. The control device of this invention compares the detected pH value with a preset target pH value, and then controls the opening and closing of the coarse regulating valve and / or the fine regulating valve based on the deviation value ΔpH obtained after comparison. This enables precise control of the pH value, ensuring the stability of the nickel-iron leaching solution and the purity of the product. By combining ORP value, temperature, and reaction time, the device determines whether the preset discharge standard is met, completely replacing manual experience and avoiding over-leaching or incomplete leaching caused by human factors.

Description

Technical Field

[0001] This invention relates to the field of hydrometallurgy, and more particularly to an automatic control device for the leaching reaction of nickel-iron powder. Background Technology

[0002] Nickel-iron powder is an important raw material for the preparation of nickel-iron alloys, nickel-iron-based battery materials, and catalysts. The leaching reaction is the core step in the nickel-iron powder processing technology. This process involves the dissolution reaction of nickel-iron powder under acidic conditions, requiring precise control of multiple process parameters such as pH value and determination of the reaction endpoint. The existing pH value is adjusted using only one regulating valve, resulting in low control precision; the determination of the reaction endpoint relies on human experience, which not only poses safety hazards but also cannot be quantitatively controlled, leading to large performance fluctuations between different batches of products due to differences in endpoint determination. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes an automatic control device for the leaching reaction of nickel-iron powder.

[0004] The technical solution of the present invention is as follows: A reaction assembly includes a heating reaction tank, a nickel-iron powder slurry tank, an acid storage tank, and a control device. The heating reaction tank is equipped with a pH sensor, a temperature sensor, and an ORP detector. The nickel-iron powder slurry tank is connected to the inlet of the heating reaction tank. The acid storage tank is connected to the heating reaction tank via a first pipe and a second pipe. A coarse regulating valve is installed on the first pipe, and a fine regulating valve is installed on the second pipe. The control device is electrically connected to the pH sensor, the temperature sensor, the ORP detector, the coarse regulating valve, and the fine regulating valve. The control device compares the detected pH value fed back by the pH sensor with a preset target pH value, and then controls the opening and closing of the coarse regulating valve and / or the fine regulating valve based on the deviation value ΔpH obtained after the comparison. The control device determines whether the preset discharge standard is met based on the temperature value fed back by the temperature sensor, the ORP value fed back by the ORP detector, and the reaction time of the heating reaction tank. If the standard is met, the heating reaction tank discharges material.

[0005] Furthermore, The deviation value ΔpH is the detected pH value minus the preset target pH value; The step of controlling the opening and closing of the coarse regulating valve and / or the fine regulating valve based on the deviation value ΔpH obtained after comparison includes: When ΔpH>0.3, the control device activates the coarse regulating valve and the fine regulating valve; When 0.1 < ΔpH ≤ 0.3, the control device closes the coarse adjustment valve and starts the fine adjustment valve; When ΔpH≤0.1, the control device closes the coarse regulating valve and the fine regulating valve.

[0006] Furthermore, the preset output standard is as follows: The rate of change of the ORP value over a continuous 60 seconds is less than 3 mV / s; The rate of change of the temperature value over a continuous 120 seconds is less than 0.5℃ / min; The reaction time reaches a preset minimum value, which is 2 to 4 hours.

[0007] Furthermore, it also includes a pure water tank, which is connected to the heating reaction tank via a third pipe, and the third pipe is equipped with a water supply valve; The heating reaction tank is equipped with a first liquid level sensor, and the control device is electrically connected to the first liquid level sensor and the water supply valve respectively.

[0008] Furthermore, it also includes a high-level tank, the inlet of which is located at the top of the heating reaction tank, the high-level tank being located above the heating reaction tank, a fourth pipe connecting the bottom of the high-level tank to the inlet, the fourth pipe being equipped with a first feeding valve, and a fifth pipe connecting the bottom of the nickel-iron powder slurry tank to the top of the high-level tank, the fifth pipe being equipped with a second feeding valve.

[0009] Furthermore, a second liquid level sensor is installed in the high-level tank, and the control device is electrically connected to the first feed valve, the second feed valve, and the second liquid level sensor, respectively.

[0010] Furthermore, it also includes a nitrogen water seal tank, and the top of the heating reaction tank has a gas outlet, which is connected to the nitrogen water seal tank. Furthermore, the heating reaction tank is equipped with a pressure sensor, the heating reaction tank is connected to a nitrogen supply pipeline, the nitrogen supply pipeline is equipped with a nitrogen supply valve, and the control device is electrically connected to the pressure sensor and the nitrogen supply valve respectively. Furthermore, the heating reaction tank is connected to a steam supply pipe, the steam supply pipe is equipped with a steam supply valve, and the control device is electrically connected to the steam supply valve. Furthermore, it also includes a main discharge pipe, wherein multiple reaction components are provided, and each of the outlets of the multiple reaction components is connected to a discharge pipe, and the multiple discharge pipes are all connected to the main discharge pipe. Each discharge pipe is provided with a discharge valve, and the control device is electrically connected to the multiple discharge valves.

[0011] The automatic control device for nickel-iron powder leaching reaction according to the present invention has at least the following technical advantages: 1. The control device compares the detected pH value from the pH sensor with the preset target pH value, and then controls the opening and closing of the coarse adjustment valve and / or fine adjustment valve based on the deviation value ΔpH obtained after comparison. This enables precise control of the pH value, ensuring the stability of the nickel-iron leaching solution and the purity of the product. By combining ORP value, temperature, and reaction time, it determines whether the preset discharge standard is met, completely replacing manual experience and avoiding over-leaching or incomplete leaching caused by human factors. This improves the nickel-iron recovery rate and avoids large performance fluctuations between different batches of products due to differences in endpoint determination, realizing the automatic leaching reaction of nickel-iron powder.

[0012] 2. Multiple reaction components are set up, and all outlets are connected in parallel to a main discharge pipe. The control device can control multiple discharge valves, and thus the control device can control multiple reaction components to operate alternately. For example, if there are two reaction components, that is, two heating reaction tanks, the control device controls one heating reaction tank to feed and react, and the control device controls the other heating reaction tank to discharge.

[0013] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0014] Additional aspects and advantages of the present invention will become apparent and readily understood from the description of the technical solutions taken in conjunction with the following drawings, wherein: Figure 1 This is a schematic diagram showing the connection between the heating reaction tank and the nickel-iron powder slurry tank, the high-level tank, and the acid storage tank. Figure 2 This is a schematic diagram of the connection between the heating reaction tank and the pure water tank; Figure 3 This is a schematic diagram of the reaction assembly. Figure 4 A schematic diagram showing the connection between the heating reaction tank and the nickel-iron powder slurry tank and the high-level tank; Figure 5 A schematic diagram showing that the nickel-iron powder slurry tank, the high-level tank, the nitrogen supply pipeline, the nitrogen water seal tank, and the steam supply pipeline are all connected to the heating reaction tank; Figure 6 This is a schematic diagram of the structure where two reaction components are connected to the main discharge pipe. Figure 7 This is a schematic diagram showing the connection between the nitrogen water seal tank and the heating reaction tank.

[0015] Reference numerals: Reaction assembly 100, Heated reaction tank 200, Inlet 201, Outlet 202, pH sensor 210, Temperature sensor 220, ORP detector 230, First liquid level sensor 240, Gas outlet 250, Pressure sensor 260, Nitrogen supply pipeline 270, Nitrogen supply valve 271, Steam supply pipeline 280, Steam supply valve 281, Discharge pipe 290, Discharge valve 291, Nickel-iron powder slurry tank 300, Acid storage tank 400, First pipeline 410. Coarse regulating valve 411, second pipeline 420, fine regulating valve 421, pure water tank 500, third pipeline 510, water replenishment valve 511, high-level tank 600, fourth pipeline 610, first feed valve 611, fifth pipeline 620, second feed valve 621, second liquid level sensor 630, nitrogen water seal tank 700, tank body 710, liquid level 720, exhaust pipe 730, air outlet 740, liquid level gauge 750, primary water pipeline 760, water inlet valve 761, main discharge pipeline 800. Detailed Implementation

[0016] The technical solutions of the present invention are described in detail below. Examples of these technical solutions are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The technical solutions described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0017] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0018] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0019] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0020] Reference Figure 1As shown, the automatic control device for nickel-iron powder leaching reaction provided in the embodiment of the present invention includes a reaction assembly 100, which includes a heating reaction tank 200, a nickel-iron powder slurry tank 300, an acid storage tank 400, and a control device (not shown in the figure). The heating reaction tank 200 is equipped with a pH sensor 210, a temperature sensor 220, and an ORP detector 230. The nickel-iron powder slurry tank 300 is connected to the inlet 201 of the heating reaction tank 200. The acid storage tank 400 is connected to the heating reaction tank 200 through a first pipe 410 and a second pipe 420. A coarse regulating valve 411 is provided on the first pipe 410, and a fine regulating valve 411 is provided on the second pipe 420. The control device is electrically connected to the pH sensor 210, temperature sensor 220, ORP detector 230, coarse control valve 411, and fine control valve 421 respectively. The control device compares the detected pH value fed back by the pH sensor 210 with the preset target pH value, and then controls the opening and closing of the coarse control valve 411 and / or the fine control valve 421 according to the deviation value ΔpH obtained after comparison. The control device judges whether the preset discharge standard is met based on the temperature value fed back by the temperature sensor 220, the ORP value fed back by the ORP detector 230, and the reaction time of the heating reaction tank 200. If it is met, the outlet 202 of the heating reaction tank 200 discharges the material.

[0021] The control device compares the detected pH value fed back by the pH sensor 210 with the preset target pH value, and then controls the opening and closing of the coarse regulating valve 411 and / or the fine regulating valve 421 based on the deviation value ΔpH obtained after comparison. This enables precise control of the pH value, ensuring the stability of the nickel-iron leaching solution and the purity of the product. By combining ORP value, temperature, and reaction time, it determines whether the preset discharge standard is met, completely replacing manual experience and avoiding over-leaching or incomplete leaching caused by human factors. This improves the nickel-iron recovery rate and avoids large performance fluctuations between different batches of products due to differences in endpoint determination, thus realizing the automatic leaching reaction of nickel-iron powder.

[0022] During operation, the nickel-iron powder slurry tank 300 conveys the nickel-iron powder slurry to the heating reaction tank 200, where a heating reaction takes place. During the nickel-iron leaching reaction, the metal powder dissolves and consumes hydrogen ions, causing the pH value to rise. The pH sensor 210, temperature sensor 220, and ORP detector 230 are all activated, providing real-time feedback of pH, temperature, and ORP values ​​to the control device. The control device compares the detected pH value with the preset target pH value and then controls the opening and closing of the coarse adjustment valve 411 and / or the fine adjustment valve 421 based on the deviation value ΔpH obtained after comparison. For example, when the pH value is high, the coarse adjustment valve is activated simultaneously. The liquid in the acid storage tank 400 enters the heating reaction tank 200 simultaneously through the first pipe 410 and the second pipe 420 via valves 411 and 421. When the pH value is low, both the coarse regulating valve 411 and the fine regulating valve 421 are closed, preventing the liquid in the acid storage tank 400 from being discharged, thus achieving precise pH control. After the nickel-iron leaching reaction has been going on for a period of time, the control device also compares the temperature value, ORP value, and reaction time with the preset discharge standard. If they meet the standard, the heating reaction tank 200 discharges the product, thus eliminating the reliance on manual experience to determine whether the discharge standard is met and ensuring that the performance difference between each batch of products is not significant.

[0023] Specifically, if the temperature, ORP, and reaction time do not meet the preset discharge standards, the heating reaction tank 200 continues to react, and the control device continuously judges whether the temperature, ORP, and reaction time meet the preset discharge standards. If they do, the heating reaction tank 200 discharges the material.

[0024] Specifically, the nickel-iron powder slurry tank 300 can pump the nickel-iron powder slurry into the heating reaction tank 200, or the nickel-iron powder slurry in the nickel-iron powder slurry tank 300 can automatically enter the heating reaction tank 200 by its own weight.

[0025] Specifically, the control device is able to detect the reaction time of the heated reaction tank 200.

[0026] Furthermore, The deviation value ΔpH is the detected pH value minus the preset target pH value; The opening and closing of the coarse regulating valve 411 and / or the fine regulating valve 421 are controlled based on the deviation value ΔpH obtained after comparison, including: When ΔpH>0.3, the control device activates the coarse regulating valve 411 and the fine regulating valve 421; When 0.1 < ΔpH ≤ 0.3, the control device closes the coarse adjustment valve 411 and starts the fine adjustment valve 421; When ΔpH≤0.1, the control device closes the coarse regulating valve 411 and the fine regulating valve 421.

[0027] Coarse adjustment mode: When ΔpH>0.3, it is determined that the pH value is too high. At the same time, the coarse adjustment valve 411 and the fine adjustment valve 421 are activated. The liquid in the acid storage tank 400 enters the heating reaction tank 200 through the first pipe 410 and the second pipe 420 simultaneously for rapid acid addition and adjustment. Fine adjustment mode: When 0.1 < ΔpH ≤ 0.3, the pH value is determined to be slightly high. The control device closes the coarse adjustment valve 411 and only opens the fine adjustment valve 421. The liquid in the acid storage tank 400 enters the heating reaction tank 200 through the second pipe 420 for slow and fine acid adjustment. Steady-state mode: When ΔpH≤0.1, the pH value is determined to be within the allowable range. The control device closes the coarse adjustment valve 411 and the fine adjustment valve 421, relying on the buffering capacity of the reaction system to maintain pH stability.

[0028] When ΔpH is negative, it indicates that the acidity is too strong. At this time, there is no need to add acid. Keep the valve closed and let the reaction consume hydrogen ions naturally to make the pH rise.

[0029] Understandably, the coarse regulating valve 411 is a large-diameter valve with a rated flow coefficient accounting for 70%-85% of the total flow, used for rapid response; while the fine regulating valve 421 is a small-diameter, high-precision needle valve with a rated flow coefficient accounting for 15%-30% of the total flow, used for fine regulation.

[0030] Specifically, both the coarse regulating valve 411 and the fine regulating valve 421 can be connected in series with independent high-precision flow meters, making it convenient for operators to observe.

[0031] Specifically, the first pipeline 410 is provided with a switch valve downstream of the coarse regulating valve 411 and the second pipeline 420 is provided with a switch valve downstream of the fine regulating valve 421. The switch valve further closes the first pipeline 410 when the coarse regulating valve 411 closes the first pipeline 410, and further closes the second pipeline 420 when the fine regulating valve 421 closes the second pipeline 420.

[0032] Furthermore, the preset output standard is: The rate of change of the ORP value over 60 consecutive seconds is less than 3 mV / s; The rate of change of temperature over 120 consecutive seconds is less than 0.5℃ / min; The reaction time reaches the preset minimum value, which is 2 to 4 hours.

[0033] When the ORP value, temperature, and reaction time are within the above range, the reaction effect is optimal and the discharge standard is met.

[0034] Specifically, when discharging the material, the heating reaction tank 200 stops heating.

[0035] Furthermore, such as Figure 2 ,3 As shown, it also includes a pure water tank 500, which is connected to the heating reaction tank 200 through a third pipe 510. The third pipe 510 is equipped with a water supply valve 511. The heating reaction tank 200 is equipped with a first liquid level sensor 240, and the control device is electrically connected to the first liquid level sensor 240 and the water supply valve 511 respectively.

[0036] The first liquid level sensor 240 can detect the liquid level in the heating reaction tank 200. When the liquid level is lower than the preset liquid level, the control device opens the water supply valve 511, and the pure water in the pure water tank 500 enters the heating reaction tank 200 through the third pipe 510.

[0037] Before the reaction begins, the control device calculates the initial liquid level setpoint based on the initial feed rate (mass of nickel-iron powder) and the target liquid-to-solid ratio (typically 3:1 to 6:1, preferably 5:1). For example, for a 280m... 3 The heating reaction tank is 200 cubic meters, and approximately 50 tons of nickel-iron powder are fed in, requiring the addition of about 250 cubic meters of water. 3 The corresponding liquid level is approximately 3.5m. During the reaction, due to high-temperature evaporation, the liquid level will gradually drop below 3.5m. The control device monitors the liquid level in real time through the first liquid level sensor 240. When the liquid level is below 3.5m, the control device opens the water supply valve 511, and the pure water tank 500 is transported to the heated reaction tank 200 through the third pipe 510 to replenish water to 3.5m, ensuring that the liquid-solid ratio remains constant throughout the reaction.

[0038] Specifically, the pure water tank 500 can pump pure water into the heating reaction tank 200, or the pure water in the pure water tank 500 can automatically enter the heating reaction tank 200 by its own weight.

[0039] Furthermore, such as Figure 3 , 4 As shown, it also includes a high-level tank 600, with an inlet 201 located at the top of the heating reaction tank 200. The high-level tank 600 is located above the heating reaction tank 200. A fourth pipe 610 is connected between the bottom of the high-level tank 600 and the inlet 201. The fourth pipe 610 is equipped with a first feed valve 611. A fifth pipe 620 is connected between the bottom of the nickel-iron powder slurry tank 300 and the top of the high-level tank 600. The fifth pipe 620 is equipped with a second feed valve 621.

[0040] By setting up a high-level tank 600, the high-level tank 600 adopts a gravity-flow method for feeding materials, so that the nickel-iron powder slurry in the high-level tank 600 enters the heating reaction tank 200 by its own weight, avoiding the risk of pressure fluctuations and mechanical failures caused by pumping.

[0041] During operation, the second feed valve 621 is activated, and the nickel-iron powder slurry in the nickel-iron powder slurry tank 300 enters the high-level tank 600 through the fifth pipe 620. When the slurry in the high-level tank 600 reaches a certain amount, the first feed valve 611 is activated, and the nickel-iron powder slurry in the high-level tank 600 enters the fourth pipe 610 by its own weight, and then enters the heating reaction tank 200 through the fourth pipe 610 and the inlet 201.

[0042] Specifically, a radar level gauge is installed on the top of the high-level tank 600. When the liquid level is lower than the preset value, the radar level gauge feeds back the liquid level data to the control device. The control device then causes the nickel-iron powder slurry tank 300 to replenish the high-level tank 600, thereby achieving automatic replenishment of the liquid and keeping the liquid level in the high-level tank constant (usually maintaining a liquid volume of 1.5~1.8m3). This ensures stable pressure during the feeding process and guarantees the repeatability and consistency of each batch of feed.

[0043] Specifically, the nickel-iron powder slurry tank 300 can pump the nickel-iron powder slurry into the high-level tank 600, or the nickel-iron powder slurry in the nickel-iron powder slurry tank 300 can automatically enter the high-level tank 600 by its own weight.

[0044] Furthermore, such as Figure 4 As shown, the high-level tank 600 is equipped with a second liquid level sensor 630, and the control device is electrically connected to the first feed valve 611, the second feed valve 621 and the second liquid level sensor 630 respectively.

[0045] The second liquid level sensor 630 can feed back the liquid level in the high-level tank 600 to the control device in real time, enabling the control device to automatically replenish the liquid. Specifically, when the high-level tank 600 is below the preset liquid level, the control device opens the second feeding valve 621, allowing the nickel-iron powder slurry tank 300 to feed nickel-iron powder slurry into the high-level tank 600. When the high-level tank 600 is above the preset liquid level, the control device closes the second feeding valve 621, stopping the feeding of nickel-iron powder slurry from the nickel-iron powder slurry tank 300. The control device maintains a 1.5 m depth within the high-level tank 600. 3 ~1.8 m 3 the amount of fluid; Alternatively, when the liquid level is below the lower limit (e.g., 0.3 m) 3 When the level reaches the upper limit (e.g., 1.9 m), the control device opens the second feed valve 621, and the nickel-iron powder slurry tank 300 conveys nickel-iron powder slurry into the high-level tank 600; 3 When the second feed valve 621 is closed, the liquid level in the high-level tank is automatically maintained.

[0046] When feeding, the control device opens the first feeding valve 611, and the nickel-iron powder slurry in the high-level tank 600 enters the fourth pipe 610 by its own weight, and then enters the heating reaction tank 200 through the fourth pipe 610 and the inlet 201.

[0047] Furthermore, such as Figure 3 , 5 As shown, it also includes a nitrogen water seal tank 700, and the top of the heating reaction tank 200 has a gas outlet 250, which is connected to the nitrogen water seal tank 700. The nitrogen water seal tank 700 ensures that the heating reaction tank 200 does not exceed the set opening pressure of the nitrogen water seal tank 700. When the pressure inside the heating reaction tank 200 exceeds the set opening pressure of the nitrogen water seal tank 700, the gas breaks through the water seal and is automatically discharged to the exhaust gas system, achieving rapid pressure relief. After the pressure returns to normal, the water seal automatically resets. This design avoids the jamming and failure problems that may occur with traditional safety valves. The nitrogen water seal tank 700 is directly connected to the heating reaction tank 200. Utilizing the one-way sealing principle of the water seal, it completely prevents the hydrogen gas generated in the heating reaction tank 200 from backflowing into the high-level tank 600 through the pipeline, eliminating the risk of combustion and explosion. That is, because the high-level tank 600 always maintains a certain height of liquid metal, its static pressure is greater than the gas pressure inside the reactor. Hydrogen gas will only enter the nitrogen water seal tank 700, thus preventing hydrogen gas from backflowing into the high-level tank 600.

[0048] Specifically, the water seal level of the nitrogen water seal tank 700 is maintained at 1 / 2 of the tank height, corresponding to an opening pressure of approximately 2~3 kPa. The inlet end of the nitrogen water seal tank 700 is connected to the outlet 250, and the outlet end of the nitrogen water seal tank 700 is connected to the exhaust gas treatment system (via a flame arrester).

[0049] Specifically, the exhaust gas system purifies the exhaust gas discharged from the nitrogen water seal tank 700 and then discharges it at high altitude.

[0050] Specifically, the liquid level of the nitrogen water seal tank 700 is monitored by an independent liquid level switch, and water is automatically replenished when the liquid level is low.

[0051] Specifically, such as Figure 7 As shown, the nitrogen water seal tank 700 includes a tank body 710 containing water. The water in the tank body 710 has a liquid level 720. The outlet 250 of the heating reaction tank 200 is connected to an exhaust pipe 730. The exhaust pipe 730 is inserted downward from the top of the tank body 710 into the tank body 710 and extends downward to the bottom of the tank body 710. The end of the exhaust pipe 730 away from the outlet 250 is located below the liquid level 720. The outlet end 740 of the nitrogen water seal tank 700 is located at the top of the tank body 710.

[0052] Since the end of the exhaust pipe 730 away from the outlet 250 is located below the liquid surface 720, the part of the exhaust pipe 730 below the liquid surface 720 contains a water column. The static pressure generated by the height h of the water column is ρg h, where ρ is the density of water (approximately 1000 kg / m³) and g is the acceleration due to gravity (approximately 9.8 m / s²). When the gas pressure discharged from the heating reaction tank 200 does not exceed the water seal pressure (static pressure), the gas will be sealed by the water column. The gas cannot push out the water column in the exhaust pipe 730, thus forming a water seal. When the gas pressure discharged from the heating reaction tank 200 exceeds the water seal pressure (static pressure), the gas will break the water seal and push out the water column in the exhaust pipe 730. The gas will then be discharged into the tank 710 through the end of the exhaust pipe 730 away from the outlet 250, and then discharged into the external recovery device or exhaust gas system through the outlet end 740 of the nitrogen water seal tank 700 to achieve pressure relief. After the pressure relief is completed, the water column re-enters the exhaust pipe 730 to re-seale the water seal and ensure the pressure inside the heating reaction tank 200.

[0053] Specifically, a level gauge 750 is installed on the side wall of the tank 710. The level gauge 750 detects the water level inside the tank 710. When the water level is lower than the preset water level, external primary water enters the tank 710 to achieve automatic water replenishment.

[0054] Specifically, the tank 710 is connected to an external primary water pipe 760, and the primary water pipe 760 is equipped with a water inlet valve 761. When the water level in the tank 710 is lower than the preset water level, the level gauge 750 feeds back data to the control device, and the control device opens the water inlet valve 761, so that the external primary water enters the tank 710 through the primary water pipe 760 to achieve automatic water replenishment.

[0055] Furthermore, such as Figure 5 As shown, the heating reaction tank 200 is equipped with a pressure sensor 260, and the heating reaction tank 200 is connected to a nitrogen supply pipeline 270. The nitrogen supply pipeline 270 is equipped with a nitrogen supply valve 271. The control device is electrically connected to the pressure sensor 260 and the nitrogen supply valve 271 respectively. Equipped with a pressure sensor 260, a nitrogen supply valve 271, and a nitrogen supply pipeline 270, the pressure sensor 260 monitors the pressure within the heating reaction tank 200 and feeds the pressure value back to the control device. When the pressure falls below a set threshold (e.g., 1.0 kPa), the control device opens the nitrogen supply valve 271, and the nitrogen supply pipeline 270 supplies nitrogen to the heating reaction tank 200, maintaining a slight positive pressure (1.0~2.0 kPa) at the top of the heating reaction tank 200. Once the pressure returns to normal, the control device closes the nitrogen supply valve 271. When the pressure exceeds the safety threshold (e.g., 5 kPa), the control device automatically closes the coarse regulating valve 411, the fine regulating valve 421, and the first feed valve 611, stopping the feeding and acid addition. The control device triggers an alarm, and at the same time, the nitrogen water seal tank 700 automatically releases pressure. The high-level tank 600 always maintains a certain height of liquid metal, and its static pressure is greater than the gas pressure in the heating reaction tank 200. In addition, nitrogen gas is also appropriately introduced into the heating reaction tank 200 (to ensure that the pressure inside the vessel is constant). This can prevent hydrogen gas from entering the high-level tank and the venting system.

[0056] Furthermore, such as Figure 5 As shown, the heating reaction tank 200 is connected to a steam supply pipe 280, and the steam supply pipe 280 is equipped with a steam supply valve 281. The control device is electrically connected to the steam supply valve 281.

[0057] The control device interlocks the steam supply valve 281 with the temperature sensor 220 to achieve precise temperature control (target temperature 80~95℃, fluctuation ±0.5℃). Furthermore, such as Figure 6 As shown, it also includes a main discharge pipe 800, multiple reaction components 100 are provided, and the outlets 202 of multiple reaction components 100 are connected to a discharge pipe 290. Multiple discharge pipes 290 are all connected to the main discharge pipe 800, and each discharge pipe 290 is provided with a discharge valve 291. The control device is electrically connected to multiple discharge valves 291.

[0058] Multiple reaction components 100 are provided, and all outlets 202 are connected in parallel to a total discharge pipe 800. The control device can control multiple discharge valves 291, and thus the control device can control multiple reaction components 100 to operate alternately. For example, if there are two reaction components 100, that is, two heating reaction tanks 200 are provided, the control device controls one heating reaction tank 200 to feed and react, and the control device controls the other heating reaction tank 200 to discharge.

[0059] Specifically, the pH sensor uses an acid-resistant composite electrode and is covered with a self-cleaning protective sleeve.

[0060] Specifically, the ORP detector 230 is a redox potential electrode.

[0061] Specifically, the control device is a PLC controller, which has a built-in deviation-level PID control algorithm to calculate the deviation ΔpH.

[0062] Specifically, the heating reaction tank 200 is equipped with a stirrer to accelerate the reaction speed.

[0063] Specifically, the PLC controller has a built-in dual-slot cooperative scheduling algorithm to achieve the following functions: Alternating operation mode: When one heating reaction tank 200 is in the leaching reaction stage, the other heating reaction tank 200 is unloading, cleaning, and preparing materials to achieve continuous production; Automatic feeding switching: Based on the status of each heating reaction tank 200 (idle / running / completed), the PLC automatically switches the valves to introduce raw materials into the idle heating reaction tank 200; Automatic unloading control: After the reaction endpoint is determined, the PLC automatically opens the discharge valve 291 of the corresponding heating reaction tank 200 to send the leachate to the next process; Interlock protection: When the temperature of a heating reaction tank 200 exceeds the limit, the pH is abnormal, or the stirring fails, the PLC automatically shuts off the discharge valve 291 of the heating reaction tank 200 and the heating system, and triggers an alarm.

[0064] One embodiment of the present invention: The reaction assembly 100 is configured with two components, namely two heating reaction tanks 200, which are defined as the first heating reaction tank 200 and the second heating reaction tank 200, respectively. The effective volume of a single heating reaction tank 200 is 280 m³. 3 The inner lining is made of corrosion-resistant material; the effective volume of the 600-meter high-level tank is 2 m³. 3 The elevated tank 600 is installed above the heating reaction tank 200. The installation height of the elevated tank 600 is 5.5m above the top of the heating reaction tank 200 to ensure sufficient gravity flow head. Each heating reaction tank 200 is independently equipped with a nitrogen water seal tank 700. The effective volume of the nitrogen water seal tank 700 is 100L, and the water seal liquid level is maintained at 1 / 2 of the tank height (corresponding to an opening pressure of about 2.5kPa). Based on the fundamental principle of nickel-iron powder leaching reaction, the following process parameters are set: Preset target pH value: 2.0 (allowable fluctuation ±0.1); Target temperature: 85℃ (allowable fluctuation ±0.5℃); Minimum preset reaction time: 3.5 hours (based on 280m) 3 (The mass and heat transfer characteristics of the heating reaction tank 200 were determined). Liquid-to-solid ratio: 5:1 (i.e., 5m³ of liquid-to-solid ratio per ton of nickel-iron powder) 3 water); like Figure 1-6 As shown, initialization: The control device calculates the initial liquid level setting of the heating reaction tank 200 to be 3.5m based on the feed amount (approximately 50 tons of nickel-iron powder). The control device automatically opens the second feed valve 621, and nickel-iron powder slurry is fed from the nickel-iron powder slurry tank 300 into the high-level tank 600, replenishing the liquid level in the high-level tank 600 to 1.8m. 3 Then close the second feed valve 621; Start-up and safety confirmation of nitrogen water seal tank 700: The control device detects that the pressure in the first heating reaction tank 200 is 0.9 kPa (lower than the set threshold of 1.0 kPa) through pressure sensor 260. The control device opens the nitrogen supply valve 271 and the nitrogen supply pipeline 270 replenishes nitrogen into the heating reaction tank 200. After the pressure in the heating reaction tank 200 rises to 1.5 kPa, it is closed to maintain a slight positive pressure. Feeding and Start-up of the First Heating Reaction Tank 200: The control device opens the first feed valve 611, and the mixture of nickel-iron powder and water in the high-level tank 600 enters the fourth pipe 610 by gravity, and then enters the heating reaction tank 200 through the fourth pipe 610 and inlet 201; since the volume of the high-level tank 600 is only 2 m³ 3 The heating reaction tank 200 requires approximately 250 m³. 3 The mixed slurry is therefore fed intermittently: the control device repeatedly opens and closes the second feed valve 621, and after the high-level tank 600 is emptied, the nickel-iron powder slurry tank 300 is automatically fed. The nickel-iron powder slurry tank 300 is fed repeatedly until the heating reaction tank 200 reaches the set liquid level of 3.5m. The control device records the number of feedings and accumulates the total feed amount. After the set liquid level is reached, the first feed valve 611 is closed, the control device starts the agitator, and opens the steam supply valve 281. The steam supply pipeline 280 supplies hot steam to the first heating reaction tank 200, raising the temperature in the first heating reaction tank 200 to 85℃. pH control: During the reaction, pH sensor 210 detects a pH value of 2.4 (ΔpH=+0.4) in the first heated reaction tank 200. The control device enters coarse adjustment mode, simultaneously opening coarse adjustment valve 411 and fine adjustment valve 421 to add acid. When the pH value drops to 2.12 (ΔpH=+0.12), the control device switches to fine adjustment mode, closing coarse adjustment valve 411 and slowly adding acid using only fine adjustment valve 421. When the pH value drops to 2.03 (ΔpH=+0.03), it enters steady-state mode, closing both coarse adjustment valve 411 and fine adjustment valve 421. When the pH value rises above 0.1 again, the above adjustment process is repeated. Throughout the reaction, the pH value is maintained within the range of 2.0±0.1. The second heating reaction tank 200 operates in parallel: 40 minutes after the first heating reaction tank 200 starts reacting, the control device automatically opens the first feed valve 611 of the second heating reaction tank 200, starting the feeding, stirring and heating of the second heating reaction tank 200, so as to realize alternating operation; Liquid-solid ratio maintenance: During the reaction, due to high-temperature evaporation, the first liquid level sensor 240 detects that the liquid level drops from 3.5m to 3.45m. The control device automatically opens the water supply valve 511 (diameter DN50~DN80, preferably DN65) to supply water to 3.5m, thus maintaining a constant liquid-solid ratio. Endpoint determination: After 3.5 hours of reaction, temperature sensor 220 and ORP detector 230 provide real-time feedback of temperature and ORP values ​​to the control device. If the control device detects that the ORP value changes by less than 3mV / s for 60 consecutive seconds, the temperature stabilizes at 85±0.5℃, and the reaction time reaches the preset minimum value, the control device determines that the reaction has reached the endpoint, automatically closes the steam supply valve 281, and opens the discharge valve 291 of the first heating reaction tank 200. The material in the first heating reaction tank 200 is discharged to the next process through the discharge pipe 290 and the main discharge pipe 800. After the material is discharged, the first heating reaction tank 200 is re-fed, stirred, and heated for reaction. After 3.5 hours of reaction in the second heating reaction tank 200, the endpoint determination is performed. If the result is satisfactory, the material is discharged. Results: The entire reaction process required no manual intervention. The high-level tank 600 stably fed the large heated reaction tank 200 through intermittent feeding, with a feeding error of less than 1%. The pressure in the heated reaction tank 200 was always controlled within a safe range. The pH control error of the leaching solution was ±0.08, the temperature error was ±0.5℃, and the nickel leaching rate reached over 98.5%, which is about 3% higher than the traditional process. Batch stability was significantly improved, and no hydrogen combustion or explosion occurred.

[0065] Abnormal operating conditions: If a batch of reaction produces a large amount of hydrogen due to excessively rapid addition of acid, the pressure in the heating reaction tank 200 will suddenly rise to 3.0 kPa. The nitrogen water seal tank 700 will automatically open to release pressure. At the same time, the pressure sensor 260 of the control device will detect the overpressure signal, immediately close the first feed valve 611, stop heating, and issue an audible and visual alarm.

[0066] Although the technical solutions of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these technical solutions without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An automatic control device for leaching reaction of nickel-iron powder, characterized in that, include: The reaction components include: The heating reaction tank is equipped with a pH sensor, a temperature sensor, and an ORP detector. The nickel-iron powder slurry tank is connected to the inlet of the heating reaction tank; An acid storage tank is connected to the heating reaction tank via a first pipe and a second pipe, respectively. A coarse regulating valve is installed on the first pipe and a fine regulating valve is installed on the second pipe. The control device is electrically connected to the pH sensor, the temperature sensor, the ORP detector, the coarse regulating valve, and the fine regulating valve, respectively. The control device compares the detected pH value fed back by the pH sensor with the preset target pH value, and then controls the opening and closing of the coarse regulating valve and / or the fine regulating valve based on the deviation value ΔpH obtained after the comparison. The control device determines whether the preset discharge standard is met based on the temperature value fed back by the temperature sensor, the ORP value fed back by the ORP detector, and the reaction time of the heating reaction tank. If the standard is met, the outlet of the heating reaction tank discharges the material.

2. The automatic control device for nickel-iron powder leaching reaction according to claim 1, characterized in that: The deviation value ΔpH is the detected pH value minus the preset target pH value; The step of controlling the opening and closing of the coarse regulating valve and / or the fine regulating valve based on the deviation value ΔpH obtained after comparison includes: When ΔpH>0.3, the control device activates the coarse regulating valve and the fine regulating valve; When 0.1 < ΔpH ≤ 0.3, the control device closes the coarse adjustment valve and starts the fine adjustment valve; When ΔpH≤0.1, the control device closes the coarse regulating valve and the fine regulating valve.

3. The automatic control device for nickel-iron powder leaching reaction according to claim 1, characterized in that: The preset discharge standard is: The rate of change of the ORP value over a continuous 60 seconds is less than 3 mV / s; The rate of change of the temperature value over a continuous 120 seconds is less than 0.5℃ / min; The reaction time reaches a preset minimum value, which is 2 to 4 hours.

4. The automatic control device for nickel-iron powder leaching reaction according to claim 1, characterized in that: It also includes a pure water tank, which is connected to the heating reaction tank via a third pipe, and the third pipe is equipped with a water supply valve; The heating reaction tank is equipped with a first liquid level sensor, and the control device is electrically connected to the first liquid level sensor and the water supply valve respectively.

5. The automatic control device for nickel-iron powder leaching reaction according to claim 1, characterized in that: It also includes a high-level tank, the inlet of which is located at the top of the heating reaction tank, the high-level tank being located above the heating reaction tank, a fourth pipe connecting the bottom of the high-level tank to the inlet, the fourth pipe being equipped with a first feeding valve, and a fifth pipe connecting the bottom of the nickel-iron powder slurry tank to the top of the high-level tank, the fifth pipe being equipped with a second feeding valve.

6. The automatic control device for nickel-iron powder leaching reaction according to claim 5, characterized in that: The high-level tank is equipped with a second liquid level sensor, and the control device is electrically connected to the first feed valve, the second feed valve, and the second liquid level sensor, respectively.

7. The automatic control device for nickel-iron powder leaching reaction according to claim 5 or 6, characterized in that: It also includes a nitrogen water seal tank, and the top of the heating reaction tank has a gas outlet, which is connected to the nitrogen water seal tank.

8. The automatic control device for nickel-iron powder leaching reaction according to claim 7, characterized in that: The heating reaction tank is equipped with a pressure sensor, and the heating reaction tank is connected to a nitrogen supply pipeline. The nitrogen supply pipeline is equipped with a nitrogen supply valve, and the control device is electrically connected to the pressure sensor and the nitrogen supply valve respectively.

9. The automatic control device for nickel-iron powder leaching reaction according to claim 1, characterized in that: The heating reaction tank is connected to a steam supply pipe, the steam supply pipe is equipped with a steam supply valve, and the control device is electrically connected to the steam supply valve.

10. The automatic control device for nickel-iron powder leaching reaction according to claim 1, characterized in that: It also includes a main discharge pipe, and multiple reaction components are provided. Each of the outlets of the multiple reaction components is connected to a discharge pipe. The multiple discharge pipes are all connected to the main discharge pipe. Each discharge pipe is equipped with a discharge valve. The control device is electrically connected to the multiple discharge valves.

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