Alkali liquor concentration control system for hydrogen production electrode activation

Abstract

The utility model provides an alkali liquor concentration control system for hydrogen production electrode activation, which comprises a circulating pump, a make-up pump, an alkali supplement pump, a concentration detector and a PID concentration control system, the circulating pump is used for driving alkali liquor in an alkali liquor pool to circularly flow, the make-up pump is used for supplementing a water source into the alkali liquor pool, the alkali supplement pump is used for supplementing alkali liquor into the alkali liquor pool, and the concentration detector is used for detecting the concentration of the alkali liquor in the alkali liquor pool. The concentration detector is used for monitoring the concentration of alkali liquor in the alkali liquor pool, and the PID concentration control system is used for controlling the water supplementing pump and the alkali supplementing pump to work according to an alkali liquor concentration signal fed back by the concentration detector so as to maintain the concentration of the alkali liquor in the alkali liquor pool to be constant. According to the alkali liquor concentration control system, the PID concentration control system adjusts the water supplementing pump and the alkali supplementing pump to supplement water or alkali into the alkali liquor pool according to the alkali liquor concentration signal fed back by the concentration detector, it can be guaranteed that the concentration of alkali liquor in the alkali liquor pool is constant, and the activation quality of the hydrogen production electrode is improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of hydrogen production, in particular to an alkali concentration control system for hydrogen production electrode activation. BACKGROUND

[0002] Water electrolysis hydrogen production, as a hydrogen production method with a long history, has gradually moved from the laboratory to industrial production and accounts for about 3% of the total hydrogen production in China. In addition, water electrolysis hydrogen production also provides new possibilities for large-scale, long-term storage and long-distance transportation of electric energy.

[0003] Among the many technical routes for water electrolysis hydrogen production, alkaline water electrolysis hydrogen production has become the mainstream choice due to its mature technology and low cost. The preparation technology of the electrode of the alkaline electrolytic tank, as the core component of the alkaline electrolytic tank, is particularly important. The alkali activation technology after plasma spraying of a nickel-aluminum coating, as a key technology in the electrode preparation process, is widely recognized by the industry due to its mature technology, safety and reliability. The application of this technology not only improves the performance and stability of the electrode, but also reduces the preparation cost, laying a solid foundation for the wide application of alkaline water electrolysis hydrogen production.

[0004] However, the existing electrode activation alkali concentration is detected manually at regular intervals, and water and alkali are supplemented after calculation. Due to the tedious manual detection procedure and low sampling frequency, the alkali concentration in the alkali tank fluctuates greatly in a short period of time when water and alkali are supplemented, the alkali concentration is unevenly distributed, and the product is affected. CONTENT OF THE INVENTION

[0005] In order to solve the problem of large error in manual monitoring of alkali concentration for water and alkali supplement during the hydrogen production electrode activation process in the prior art, the application provides an alkali concentration control system, which monitors the alkali concentration in the alkali tank in real time and automatically supplements water and alkali through a PID concentration control system, thereby ensuring the stability of the alkali concentration during the hydrogen production electrode activation process and improving the activation quality of the hydrogen production electrode.

[0006] The application is implemented in the following manner: the application provides an alkali concentration control system for hydrogen production electrode activation, which comprises a circulating pump, a water supplement pump, an alkali supplement pump, a concentration detector and a PID concentration control system. The circulating pump is used to drive the circulation of the alkali in the alkali tank. The water supplement pump is used to supplement water in the alkali tank. The alkali supplement pump is used to supplement alkali in the alkali tank. The concentration detector is used to monitor the alkali concentration in the alkali tank. The PID concentration control system is used to control the water supplement pump and the alkali supplement pump to work to maintain the constant alkali concentration in the alkali tank according to the alkali concentration signal fed back by the concentration detector.

[0007] Preferably, the volume of the alkali solution pool is V liters, and the flow rate of the circulating pump is not less than 4V liters / hour.

[0008] Preferably, the flow rate of the alkali supplement pump is V / 600-V / 200 liters / hour, and the flow rate of the water supplement pump is V / 75-V / 38 liters / hour.

[0009] Preferably, the flow rate of the alkali supplement pump is V / 400-V / 240 liters / hour, and the flow rate of the water supplement pump is V / 60-V / 42 liters / hour.

[0010] Preferably, the concentration detector is a refractometer.

[0011] Preferably, the circulating pump or the alkali supplement pump is a magnetic pump.

[0012] Preferably, the concentration detector is installed on a bypass of the connecting pipeline between the circulating pump and the alkali solution pool.

[0013] Preferably, the P value of the PID concentration control system is 1%-3%.

[0014] Preferably, the P value of the PID concentration control system is 2%.

[0015] Preferably, the concentration detector and the PID concentration control system are connected through a 4-20 milliampere electrical signal.

[0016] Compared with the prior art, the present application has at least the following technical effects:

[0017] 1. The alkali solution concentration control system for hydrogen production electrode activation of the present application can ensure the constant alkali solution concentration in the alkali solution pool and improve the activation quality of the hydrogen production electrode, by setting the circulating pump, the alkali supplement pump, the water supplement pump, the concentration detector, the PID concentration control system and other components, and by the concentration detector detecting the alkali solution concentration in the alkali solution pool in real time and the PID concentration control system adjusting the water supplement pump and the alkali supplement pump to supplement water or alkali into the alkali solution pool according to the alkali solution concentration signal fed back by the concentration detector.

[0018] 2. The volume of the alkali solution pool is V liters, and the flow rate of the circulating pump is not less than 4V liters / hour, so that the alkali solution concentration in the alkali solution pool can be ensured to have at least four cycles under the condition that the circulating pump is continuously working, which ensures that the concentration detector can timely respond to and detect the alkali solution concentration in the alkali solution pool and ensures the timeliness of the alkali solution concentration control.

[0019] 3. The preferred concentration detector is a refractometer. By converting the optical signal detected by the refractometer into an alkaline concentration signal, the concentration of alkaline solution in the alkaline pool can be obtained quickly and timely, making monitoring timely and efficient. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the alkaline solution concentration control system for hydrogen production electrode activation according to this application.

[0022] The meanings of the various markings in the diagram are as follows: 1. Circulation pump; 2. Concentration detector; 3. Alkali solution tank; 4. Water tank; 5. Make-up water pump; 6. Make-up alkali pump; 7. Concentrated alkali tank. Detailed Implementation

[0023] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0024] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0025] Furthermore, it should be understood that in the description of this application, terms such as "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this application 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, and therefore should not be construed as a limitation of the present invention. Positional relationships such as "upstream" and "downstream" are based on the positional relationships during normal fluid flow.

[0026] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0027] In this application, unless specifically defined otherwise, the terms "mount", "connected", "connection", "fixed", and the like, should be construed as being used in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection, can also be communication; can be direct connection, can also be indirect connection through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] In this application, unless specifically defined otherwise, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. In the description of the specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the description of the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0029] In the prior art, the alkali concentration in the hydrogen production electrode activation process is difficult to maintain relatively constant, mainly due to the following reasons: 1) alkali consumption during activation, resulting in a decrease in alkali concentration; 2) to shorten the activation time, the alkali is often heated, and the evaporation of water in the alkali causes the alkali concentration to rise; 3) after the hydrogen production electrode activation is completed, it is transferred to the next process, which causes the loss of alkali. The above three reasons cause the alkali concentration to be unable to maintain a relatively constant, which seriously affects the quality of the alkali activation of the hydrogen production electrode.

[0030] In order to solve the quality problem caused by the fluctuation of alkali concentration in the alkali activation process of the hydrogen production electrode, manual monitoring of the alkali concentration is generally required in the prior art, and water and alkali are supplemented according to the alkali concentration detection results. However, due to the tedious manual monitoring process and low sampling frequency, the alkali concentration fluctuation cannot be quickly responded, and the alkali concentration fluctuation will still affect the electrode quality.

[0031] In order to solve the above problems, the alkali concentration control system for hydrogen production electrode activation is provided, specifically, the alkali concentration control system has a circulating pump 1, a water supplement pump 5, an alkali supplement pump 6, a concentration detector 2, a PID concentration control system and the like, wherein the water supplement pump 5 is used for supplementing pure water into the alkali pool 3, the alkali supplement pump 6 is used for supplementing alkali into the alkali pool 3, the circulating pump 1 is used for driving the alkali in the alkali pool 3 to circulate, the concentration detector 2 is used for detecting the alkali concentration in the alkali pool 3, the PID concentration control system is in communication connection with the circulating pump 1, the water supplement pump 5, the alkali supplement pump 6 and the concentration detector 2, and the PID concentration control system can control the water supplement pump 5 and the alkali supplement pump 6 to work according to the alkali concentration signal fed back by the concentration detector 2 to maintain the alkali concentration in the alkali pool 3 constant.

[0032] The alkali concentration control system introduces the PID concentration control system and the concentration detector 2, the alkali concentration in the alkali pool 3 is monitored in real time by the concentration detector 2, the alkali concentration in the alkali pool 3 is adjusted by the PID concentration control system, the alkali concentration in the alkali pool 3 can be maintained relatively constant, and the alkali concentration in the alkali pool 3 can be quickly adjusted by the PID control system due to the real-time monitoring of the alkali concentration in the alkali pool 3 by the concentration detector 2, the fluctuation of the alkali concentration in the alkali pool 3 is further reduced, and the activation quality of the hydrogen production electrode is ensured.

[0033] In the application, the water supplement pump 5 is provided with pure water, the water supplement pump 5 is connected with the water tank 4, the alkali supplement pump 6 is provided with high-concentration alkali, the alkali supplement pump 6 is connected with the concentrated alkali tank 7, the water supplement pump 5 and the alkali supplement pump 6 are connected with the alkali pool 3 respectively, the opening and closing and flow rate of the water supplement pump 5 and the alkali supplement pump 6 are controlled by the relay of the PID concentration control system, the PID concentration control system is in communication control with the concentration detector 2 through 4-20 milliamperes electrical signal, and the alkali concentration signal fed back by the concentration detector 2 can be received in real time.

[0034] In the application, the circulating pump 1 and the alkali pool 3 have a communication pipeline for alkali circulation, the concentration detector 2 is connected on the bypass branch of the communication pipeline, the concentration detector 2 does not affect the alkali flow in the communication pipeline in this way, the flow of the alkali circulation is ensured to be smooth, and the concentration detector 2 can quickly sense the alkali concentration in the alkali pool 3 due to the vertical installation of the concentration detector 2 on the communication pipeline, the liquid in the communication pipeline has a fast flow rate, and the PID concentration control system can be adjusted in real time.

[0035] It can be understood that, in the application, the material of the circulating pump 1 and the water supplement pump 5 is preferably 316L material resistant to alkali corrosion, and is preferably a magnetic pump.

[0036] It can be understood that in the present application, the concentration detector 2 is preferably a refractometer, and the optical signal detected by the refractometer is converted into the percentage of the caustic lye concentration, so as to facilitate the water source and caustic lye supplement of the water supplement pump 5 and the caustic lye supplement pump 6.

[0037] In the present application, the caustic lye volume in the caustic lye pool 3 is V liters, and the flow rate of the circulating pump 1 is not less than 4V liters / hour. In this way, the caustic lye in the caustic lye pool 3 has a relatively fast circulation speed, the caustic lye concentration detected by the concentration detector 2 can represent the caustic lye concentration in the caustic lye pool 3, and the regulation reliability of the PID concentration control system is ensured.

[0038] It can be understood that, in order to reduce the fluctuation of the caustic lye concentration and quickly respond to the caustic lye concentration, optionally, the PID concentration control system adopts proportional control, and the P value is 1%-3%, preferably 2%.

[0039] When the concentration detector 2 detects that the caustic lye concentration in the caustic lye pool 3 is higher than (1+P) times of the target caustic lye concentration, the caustic lye concentration in the caustic lye pool 3 is too high, the PID concentration control system controls the relay of the water supplement pump 5 to be closed, the water supplement pump 5 supplements water into the caustic lye pool 3, and the caustic lye concentration in the caustic lye pool 3 is reduced; when the concentration detector 2 detects that the caustic lye concentration in the caustic lye pool 3 is lower than (1-P) times of the target caustic lye concentration, the caustic lye concentration in the caustic lye pool 3 is too low, the PID concentration control system controls the relay of the caustic lye supplement pump 6 to be closed, the caustic lye supplement pump 6 supplements caustic lye into the caustic lye pool 3, and the caustic lye concentration in the caustic lye pool 3 is increased. Through the feedback regulation between the concentration detector 2 and the PID concentration control system, the caustic lye concentration in the caustic lye pool 3 can be maintained at the target caustic lye concentration.

[0040] In the present application, the flow rate of the caustic lye supplement pump 6 is controlled to be V / 600-V / 200 liters / hour, and the flow rate of the water supplement pump 5 is controlled to be V / 75-V / 38 liters / hour. By setting appropriate flow rates of the caustic lye supplement pump 6 and the water supplement pump 5, the caustic lye concentration in the caustic lye pool 3 can be quickly adjusted, the fluctuation of the caustic lye concentration in the caustic lye pool 3 can be reduced, and the activation quality of the hydrogen production electrode can be ensured. Preferably, the flow rate of the caustic lye supplement pump 6 is controlled to be V / 400-V / 240 liters / hour, and the flow rate of the water supplement pump 5 is controlled to be V / 60-V / 42 liters / hour.

[0041] Embodiment one.

[0042] The embodiment adopts the aforementioned alkali concentration control system for hydrogen production electrode activation, wherein the volume of the alkali pool 3 is 5 cubic meters, the target alkali concentration is 20%±1%, the alkali concentration supplemented by the alkali supplement pump 6 is 20%, the PID concentration control system adopts proportional control, wherein the P value is 1, the flow rate of the alkali supplement pump 6 is 17 liters / hour, the flow rate of the water supplement pump 5 is 100 liters / hour, and the flow rate of the circulating pump 1 is 340 liters / minute.

[0043] Comparative Example 1.

[0044] The comparative example adopts the aforementioned alkali concentration control system for hydrogen production electrode activation, wherein the volume of the alkali pool 3 is 5 cubic meters, the target alkali concentration is 20%±1%, the alkali concentration supplemented by the alkali supplement pump 6 is 20%, the PID concentration control system adopts proportional control, wherein the P value is 1, the flow rate of the alkali supplement pump 6 is 17 liters / hour, the flow rate of the water supplement pump 5 is 100 liters / hour, and the flow rate of the circulating pump 1 is 100 liters / minute.

[0045] Comparative Example 2.

[0046] The comparative example adopts the aforementioned alkali concentration control system for hydrogen production electrode activation, wherein the volume of the alkali pool 3 is 5 cubic meters, the target alkali concentration is 20%±1%, the alkali concentration supplemented by the alkali supplement pump 6 is 20%, the PID concentration control system adopts proportional control, wherein the P value is 1, the flow rate of the alkali supplement pump 6 is 100 liters / hour, the flow rate of the water supplement pump 5 is 100 liters / hour, and the flow rate of the circulating pump 1 is 340 liters / minute.

[0047] Comparing the hydrogen production electrodes activated by Example 1, Comparative Example 1, and Comparative Example 2, it is found that the aluminum content of the hydrogen production electrode activated by Example 1 is significantly more consistent.

[0048] This is because, in Example 1, by reasonably setting the flow rates of the water supplement pump 5, the alkali supplement pump 6, and the circulating pump 1 during operation, the alkali concentration in the alkali pool 3 can be basically maintained stable. After using the system to control the alkali concentration, the labor cost is reduced, the alkali concentration fluctuation range is small, and the aluminum content of the activated product is basically consistent. In Comparative Example 1, the flow rate of the circulating pump 1 is small, the alkali circulation is not sufficient compared with Example 1, the online monitoring of the alkali after water and alkali supplement fails to feedback in time, the water and alkali supplement is out of control, the alkali concentration in the alkali pool 3 fluctuates larger than that in Example 1, thereby affecting the aluminum content in the product. In Comparative Example 2, the flow rate of the alkali supplement pump 6 is large during operation, the supplemented alkali concentration is high, the online monitoring of the alkali after alkali supplement fails to feedback in time, the alkali supplement is out of control, the alkali concentration fluctuates large, and thereby affecting the aluminum content in the product.

[0049] It can be understood that, compared with the manual adjustment scheme of artificial monitoring of alkali concentration in the prior art, the consistency of the aluminum content of the activated hydrogen production electrode is greatly improved in embodiment one, comparative example one and comparative example two.

[0050] The above description is only the preferred embodiment of the present application, and is not intended to limit the scope of the present application. Any equivalent changes and modifications made in accordance with the present application are included in the scope of the present application, and are not listed one by one here.

Claims

1. A control system for the concentration of alkaline solution used for activating a hydrogen production electrode, characterized in that, The system includes a circulation pump, a water replenishment pump, an alkali replenishment pump, a concentration detector, and a PID concentration control system. The circulation pump drives the circulation of alkali solution in the alkali solution tank. The water replenishment pump replenishes water to the alkali solution tank. The alkali replenishment pump replenishes alkali solution to the alkali solution tank. The concentration detector monitors the concentration of alkali solution in the alkali solution tank. The PID concentration control system controls the operation of the water replenishment pump and the alkali replenishment pump based on the alkali solution concentration signal fed back by the concentration detector to maintain a constant alkali solution concentration in the alkali solution tank.

2. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The volume of the alkali solution tank is V liters, and the flow rate of the circulating pump is not less than 4V liters / hour.

3. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 2, characterized in that, The flow rate of the alkali replenishment pump is V / 600-V / 200 liters / hour, and the flow rate of the water replenishment pump is V / 75-V / 38 liters / hour.

4. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 3, characterized in that, The flow rate of the alkali replenishment pump is V / 400-V / 240 liters / hour, and the flow rate of the water replenishment pump is V / 60-V / 42 liters / hour.

5. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The concentration detector is a refractometer.

6. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The circulating pump or the alkali replenishment pump is a magnetic pump.

7. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The concentration detector is installed on the bypass of the connecting pipeline between the circulating pump and the alkali tank.

8. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The P value of the PID concentration control system is 1%-3%.

9. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The P value of the PID concentration control system is 2%.

10. The alkaline solution concentration control system for hydrogen production electrode activation according to claim 1, characterized in that, The concentration detector and the PID concentration control system are connected by a 4-20 mA electrical signal.

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