CN115976572B - Electrolyzer gas purity control method, system, device and storage medium - Google Patents

Abstract

The invention discloses a method, a system, a device and a storage medium for controlling the gas purity of an electrolytic tank, wherein the method comprises the steps of obtaining real-time pressure and pressure difference of a cathode side and an anode side of the electrolytic tank, then obtaining the change trend of the hydrogen content in oxygen in the electrolytic tank according to the pressure and pressure difference of the cathode side and the anode side, and adjusting the pressure of the cathode side and/or the anode side based on the change trend.

Description

Electrolyzer gas purity control method, system, device and storage medium

technical field

The invention relates to the technical field of electrolyzed water, in particular to a method, system, device and storage medium for controlling the gas purity of an electrolyzer.

Background technique

As an emerging power system energy storage method, hydrogen energy storage has the advantages of clean and green, high energy density, large storage capacity, long operating life, and convenient storage and transmission compared with traditional energy storage. Therefore, the comprehensive development and utilization of coupled hydrogen energy storage will become one of the preferred options for the efficient operation of wind power and photovoltaics.

However, renewable energy such as wind energy and solar energy has the characteristics of randomness, volatility, and uncertainty. When the load is low, the production rate of oxygen will be lower than the crossover rate of hydrogen, resulting in an increase in the hydrogen content in oxygen. When the content of hydrogen in oxygen exceeds 4%, there is a risk of explosion. The international water electrolysis hydrogen production standard stipulates that the maximum content of hydrogen in oxygen is 2%. When it exceeds 2%, the system needs to be forced to stop running. Content is the main limiting factor in the working load range of the electrolyser.

Hydrogen in oxygen is the result of hydrogen crossing through the membrane and depends on many factors including membrane properties (porosity, tortuosity, and thickness), operating pressure and temperature, split or hybrid electrolyte circulation, and current density. The existing technology monitors the hydrogen content in oxygen through a sensor, which has a lag in the adjustment of gas purity and a long response time, which may cause the hydrogen content in the oxygen in the electrolyzer to exceed the safe range and cause equipment shutdown.

Contents of the invention

In view of this, the embodiment of the present invention provides a method, system, device and storage medium for controlling the gas purity of an electrolyzer to solve the problem that the existing control method has hysteresis and cannot respond in time, which causes the hydrogen content in the oxygen in the electrolyzer There are technical problems that may cause equipment shutdown beyond the safety range.

The technical scheme that the present invention proposes is as follows:

The first aspect of the embodiments of the present invention provides a method for controlling the gas purity of an electrolyzer, including: obtaining the pressure and pressure difference between the cathode side and the anode side of the electrolyzer; A variation trend of hydrogen content in oxygen in the electrolyzer; adjusting the pressure on the cathode side and/or the anode side based on the variation tendency.

Optionally, adjusting the pressure on the cathode side and/or the anode side based on the change trend includes: judging whether the hydrogen content in the oxygen keeps increasing and exceeds a first set value based on the change trend; If it keeps growing continuously and exceeds the first set value, then calculate the adjustment parameters on the cathode side and the anode side, and adjust the pressure on the cathode side and/or the anode side according to the adjustment parameters; if If the constant increase is not maintained or the first set point is not exceeded, the pressure on the cathode side and/or the anode side is not adjusted.

Optionally, adjusting the pressure on the cathode side and/or the anode side according to the adjustment parameter includes: judging whether the adjusted liquid level of the gas-liquid separator exceeds the preset upper and lower limits according to the adjustment parameter; if not If it exceeds the preset upper and lower limits, adjust the pressure on the cathode side or the anode side according to the adjustment parameters so that the pressure on the anode side is higher than the pressure on the cathode side; if the preset upper and lower limits are exceeded, then simultaneously The pressure on the cathode side and the anode side is reduced.

Optionally, after the pressure on the cathode side and/or the anode side is adjusted according to the adjustment parameter, it further includes: predicting the Whether the hydrogen content in oxygen is lower than the second set value; if it is lower than the second set value, the pressure on the cathode side and the pressure on the anode side are respectively restored to the pressure before adjustment.

Optionally, the adjusting parameters include adjusting the pressure difference and adjusting time, and the calculating the adjusting parameters on the cathode side and the anode side includes: The relationship between the pressure on the anode side and the pressure difference, the liquid level of the gas-liquid separator, and the hydrogen content in oxygen obtains the adjustment pressure difference and the adjustment time; adjust the cathode side and/or the anode according to the adjustment parameters The method of the pressure on the side is: based on the adjustment parameters, the first pressure regulating valve and the second pressure regulating valve respectively arranged at the cathode side outlet and the anode side outlet of the electrolytic cell adjust the cathode side and/or the the pressure on the anode side.

Optionally, obtaining the change trend of hydrogen content in oxygen in the electrolytic cell according to the pressure difference between the cathode side and the anode side includes: inputting the pressure and the pressure difference between the cathode side and the anode side of the electrolysis cell to a preset prediction model of hydrogen content in oxygen; the change trend of hydrogen content in oxygen is obtained through the preset prediction model of hydrogen content in oxygen.

Optionally, the process of constructing the preset prediction model of hydrogen in oxygen includes: constructing the initial hydrogen content in oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convective flux of dissolved hydrogen in the electrolyte Prediction model: constructing the preset hydrogen content prediction model in oxygen according to the impurity accumulation process of hydrogen dynamics in oxygen and the initial hydrogen content prediction model in oxygen.

Optionally, before constructing the hydrogen content prediction model in the initial oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convective flow of dissolved hydrogen in the electrolyte, it also includes: The gas mixing flux is obtained by the flow rate; the hydrogen diffusion flux is obtained according to the effective diffusion coefficient of hydrogen passing through the diaphragm, the thickness of the diaphragm and the concentration difference of hydrogen; according to the pressure difference between the cathode side and the anode side, the permeability of the diaphragm, and the power of the electrolyte The viscosity, the solubility of hydrogen in the catholyte, the pressure on the cathode side and the thickness of the membrane obtain the hydrogen convective flow.

Optionally, the way to adjust the pressure on the cathode side and/or the anode side is to adjust the pressure through the first pressure regulating valve and the second pressure regulating valve respectively arranged at the cathode side outlet and the anode side outlet of the electrolytic cell. Flow rate of gas release on the cathode side and/or on the anode side.

The second aspect of the embodiment of the present invention provides an electrolytic cell gas purity control system, including a controller, a differential pressure transmitter, a first pressure regulating valve, a second pressure regulating valve, a cathode pressure gauge and an anode pressure gauge. The pressure transmitter, the first pressure regulating valve, the second pressure regulating valve, the cathode pressure gauge and the anode pressure gauge are all connected to the controller, and the first pressure regulating valve and the second pressure regulating valve are respectively arranged in the electrolytic cell The anode side outlet and the cathode side outlet, the cathode pressure gauge and the anode pressure gauge are respectively set on the anode side and the cathode side of the electrolytic cell, the first pressure regulating valve is used to adjust the pressure on the anode side, and the second pressure regulator The valve is used to adjust the pressure on the cathode side, the cathode pressure gauge is used to collect the pressure on the cathode side of the electrolyzer, the anode pressure gauge is used to collect the pressure on the anode side of the electrolyzer, and the differential pressure transmitter is used to collect The pressure difference between the cathode side and the anode side of the electrolytic cell, the controller is used to receive the pressure difference collected by the differential pressure transmitter, the pressure on the cathode side collected by the cathode pressure gauge and the anode pressure collected by the anode pressure gauge According to the pressure and pressure difference of the cathode side and the anode side of the electrolyzer, the change trend of the hydrogen content in the oxygen in the electrolyzer is obtained, and the first pressure regulating valve and/or the second pressure regulating valve are controlled based on the change trend The valves regulate the pressure on the cathode side and/or the anode side.

The third aspect of the embodiment of the present invention provides an electrolytic cell gas purity control device, including: an acquisition module, used to obtain the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell; The change trend of the hydrogen content in the oxygen in the electrolytic cell is obtained through the pressure and the pressure difference on the anode side; the regulation module is used to adjust the pressure on the cathode side and/or the anode side based on the change trend.

The fourth aspect of the embodiments of the present invention provides a computer-readable storage medium, the computer-readable storage medium stores computer instructions, and the computer instructions are used to make the computer execute any one of the first aspects of the embodiments of the present invention. The method for controlling the gas purity of an electrolyzer.

It can be seen from the above technical solutions that the embodiments of the present invention have the following advantages:

The embodiment of the present invention provides a method, system, device, and storage medium for controlling the gas purity of an electrolyzer, by obtaining the pressure and pressure difference between the cathode side and the anode side of the electrolyzer, and then according to the pressure of the cathode side and the anode side The pressure and pressure difference obtain the change trend of the hydrogen content in the oxygen in the electrolytic cell, adjust the pressure on the cathode side and/or the anode side based on the change trend, and predict the electrolytic cell through the change trend of the hydrogen content in the oxygen The hydrogen content in the oxygen in the electrolytic cell can be adjusted in time to reduce the hydrogen content in the oxygen by adjusting the pressure on the cathode side and/or the anode side in time, so as to avoid the frequent shutdown of the equipment caused by the hydrogen content in the oxygen in the electrolytic cell exceeding the safe range.

Description of drawings

In order to express the technical solutions of the embodiments of the present invention more clearly, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without making creative efforts.

Fig. 1 is the flowchart of electrolyzer gas purity control method in the embodiment of the present invention;

Fig. 2 is the flowchart of another electrolyzer gas purity control method in the embodiment of the present invention;

Fig. 3 is the structural representation of electrolyzer gas purity control system in the embodiment of the present invention;

Fig. 4 is the modular block diagram of electrolyzer gas purity control device in the embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a computer-readable storage medium in an embodiment of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The embodiment of the present invention provides a method for controlling the gas purity of an electrolyzer, as shown in Figure 1 and Figure 2, comprising:

Step S100: Obtain the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell. The electrolyzer is a device where electrolysis occurs. The cathode side of the electrolyzer produces hydrogen, the anode side produces oxygen, and the electrolyte in the electrolyzer is lye. The pressure and pressure difference between the cathode side and the anode side are obtained by setting a differential pressure transmitter, cathode pressure gauge and anode pressure gauge on the electrolytic cell.

Step S200: Obtain the change trend of the hydrogen content in the oxygen in the electrolyzer according to the pressure and pressure difference between the cathode side and the anode side. The hydrogen content in oxygen in the electrolytic cell is mainly affected by the pressure and pressure difference between the cathode side and the anode side and the liquid level of the gas-liquid separator, and the liquid level of the gas-liquid separator will change accordingly when the pressure on the cathode side and the anode side is adjusted , so the change trend of hydrogen content in oxygen in the electrolyzer can be predicted by the pressure and pressure difference between the cathode side and the anode side.

Step S300: Adjust the pressure on the cathode side and/or the anode side based on the variation trend. Specifically, the change range of the hydrogen content in oxygen can be obtained through the change trend, so as to know whether the hydrogen content in oxygen will continue to increase under the current pressure difference and exceed the maximum hydrogen content threshold in oxygen stipulated in the international water electrolysis hydrogen production standard, if Exceeding this threshold will cause the electrolyser to shut down. Therefore, by predicting the change of hydrogen content in oxygen in the electrolytic cell, different pressure control strategies can be adopted in advance, such as increasing the pressure on the anode side or reducing the pressure on the cathode side, so that the pressure on the anode side is greater than that on the cathode side. Side pressure, or reduce the pressure on the anode side and the cathode side at the same time, to avoid the situation where the hydrogen content in oxygen exceeds the set threshold and cause shutdown.

The gas purity control method of the electrolyzer according to the embodiment of the present invention obtains the pressure and pressure difference between the cathode side and the anode side of the electrolyzer, and then obtains the change of the hydrogen content in the oxygen in the electrolyzer according to the pressure and pressure difference between the cathode side and the anode side Trend, adjust the pressure on the cathode side and/or anode side based on the change trend, and predict the hydrogen content in the oxygen in the electrolytic cell through the change trend of the hydrogen content in the oxygen, so as to adjust the pressure on the cathode side and/or the anode side in time to reduce the oxygen content. Hydrogen content, to avoid the frequent shutdown of equipment caused by the hydrogen content in the oxygen in the electrolyzer exceeding the safe range.

In an embodiment, the above step S200, according to the pressure difference between the cathode side and the anode side, obtains the change trend of the hydrogen content in the oxygen in the electrolytic cell, specifically including:

Step S210: Input the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell into a preset hydrogen content prediction model in oxygen;

Step S200: Obtain the change trend of the hydrogen content in the oxygen through the preset forecasting model of the hydrogen content in the oxygen.

The preset hydrogen content prediction model in oxygen is pre-constructed based on the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell, the liquid level of the gas-liquid separator, the flow rate of the lye, the temperature of the lye, and the current density. The pressure difference on the anode side predicts the hydrogen content in oxygen model. Through this model, the actual hydrogen content in oxygen inside the electrolytic cell can be obtained in advance, and the change trend of hydrogen content in oxygen can be obtained, so as to predict the hydrogen content in oxygen.

In one embodiment, the process of constructing the hydrogen in oxygen preset prediction model of hydrogen in oxygen includes: constructing the initial hydrogen content in oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convective flow of dissolved hydrogen in the electrolyte Prediction model: construct a preset hydrogen content prediction model in oxygen based on the impurity accumulation process of hydrogen dynamics in oxygen and the initial hydrogen content prediction model in oxygen.

The hydrogen in the oxygen in the electrolysis process mainly comes from three aspects: the gas mixing under the mixed lye circulation mode, the trans-diaphragm gas convection caused by the pressure difference, and the trans-diaphragm gas diffusion caused by the concentration difference. The embodiment of the present invention considers that in the hybrid electrolyte circulation mode, the electrolyte mixing at the cathode and anode inlets causes the dissolved hydrogen and oxygen in the solution to mix with each other, and the gas mixing flux generated; the dissolved hydrogen concentration on the cathode side and the anode side The hydrogen diffusion flux caused by the difference; the hydrogen convection flow caused by the pressure difference between the cathode side and the anode side, based on the gas mixing flux, hydrogen diffusion flux and hydrogen convection flow, the hydrogen content prediction model in the initial oxygen is constructed, which can comprehensively Reflect the reason for the change of hydrogen content in oxygen.

In addition, the gas discharged from the electrolytic cell must undergo gas-liquid separation and purification treatment. At this stage, there is a dynamic impurity accumulation process of hydrogen in oxygen. Considering the impact of this process, according to the dynamic impurity accumulation process of hydrogen in oxygen and the initial hydrogen content in oxygen Prediction model A preset prediction model for hydrogen content in oxygen is built, which can predict the change trend of hydrogen content in oxygen under different working conditions.

In one embodiment, before constructing the hydrogen content prediction model in the initial oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convective flow of dissolved hydrogen in the electrolyte, the method further includes:

The gas mixing flux is obtained according to the concentration of hydrogen on the cathode side and the flow rate of the electrolyte.

Specifically, in the hybrid electrolyte circulation mode, the electrolyte mixing at the cathode and anode inlets causes the dissolved hydrogen and oxygen in the solution to mix with each other, and the gas mixing flux is calculated as:

in, Indicates the gas mixing flux; /> Indicates the concentration of hydrogen on the cathode side; V _lye indicates the flow rate of the electrolyte; /> Indicates the solubility of hydrogen in KOH solution; /> Indicates the cathode side pressure.

The hydrogen diffusion flux is obtained according to the effective diffusion coefficient of hydrogen permeating the membrane, the thickness of the membrane and the concentration difference of hydrogen.

Specifically, the hydrogen diffusion flux due to the difference in dissolved hydrogen concentration on the cathode side and the anode side Expressed as follows:

Among them, _δm represents the thickness of the diaphragm; Indicates the effective diffusion coefficient of hydrogen permeating the membrane;

Indicates the solubility of hydrogen in the catholyte; /> Indicates the concentration difference of hydrogen gas.

Hydrogen convective flow was obtained from the pressure difference between the cathode and anode sides, the permeability of the diaphragm, the kinetic viscosity of the electrolyte, the solubility of hydrogen in the catholyte, the pressure on the cathode side, and the thickness of the diaphragm.

Specifically, the convective flow of hydrogen due to the pressure difference between the cathode and anode Expressed as follows:

Among them, ΔP represents the pressure difference between cathode and anode; K _sep represents the permeability of the diaphragm; η _L represents the dynamic viscosity of the solution.

Based on the gas mixing flux, hydrogen diffusion flux and hydrogen convective flux, the initial hydrogen content prediction model in oxygen is expressed as follows:

in, Indicates the oxygen generation rate; A _sep indicates the area of the diaphragm. The gas discharged from the electrolyzer needs to undergo gas-liquid separation and purification treatment. At this stage, there is a dynamic impurity accumulation process of hydrogen in oxygen. Considering the impact of this process, according to the dynamic impurity accumulation process of hydrogen in oxygen and the initial hydrogen content prediction model in oxygen HTO ₀ constructs a preset hydrogen content prediction model in oxygen HTO ₁ is expressed as follows:

Among them, τ _j represents the separation time when oxygen passes through gas-liquid separator, scrubber and other equipment during the purification process. By presetting the hydrogen content prediction model HTO ₁ in oxygen, the real-time pressure difference inside the electrolytic cell can be used to predict the change trend of hydrogen content in oxygen under different working conditions.

The following describes the process of predicting the change trend of hydrogen content in oxygen under different working conditions through the preset prediction model of hydrogen content in oxygen in combination with specific scenarios:

The hydrogen content prediction in oxygen based on the preset hydrogen content prediction model in oxygen includes the following steps:

1. Data acquisition: Fig. 3 is a schematic structural diagram of a system applying the method for controlling the purity of an electrolyzer according to an embodiment of the present invention, the system comprising an electrolyzer, a pressure regulating valve, a cathode pressure gauge, an anode pressure gauge, a temperature transmitter, and a flow meter , lye pump, differential pressure transmitter, programmable controller, oxygen sensor in hydrogen, gas-liquid separator on hydrogen side and oxygen side, liquid level transmitter and other devices. The data that needs to be collected to build a preset hydrogen content prediction model in oxygen mainly includes: electrolyte flow rate collected by flowmeter, cathode side pressure collected by cathode pressure gauge, anode side pressure collected by anode pressure gauge, differential pressure transmitter The collected pressure difference, the cathode liquid level and the anode liquid level collected by the liquid level transmitter, the temperature collected by the temperature transmitter, and the hydrogen content in oxygen collected by the oxygen sensor in hydrogen. When measuring the pressure difference inside the electrolytic cell, due to the compressibility of gas and liquid and the hysteresis of pressure change transmission, in order to ensure accurate pressure data under different working conditions, the position of cathode pressure gauge and anode pressure gauge should be as far as possible Close to the lye outlet of the electrolytic cell.

2. Based on the data collected by the cathode pressure gauge, anode pressure gauge and differential pressure transmitter, the parameters of the preset hydrogen content prediction model in oxygen were calibrated: the experimental data were obtained under two different working conditions: (1) different pressure and Under current density, the pressure and pressure difference, liquid level, and hydrogen content in oxygen without a pressure regulating valve; (2) under constant current density, add a pressure regulating valve and adjust it to measure the pressure and Pressure difference and hydrogen content in oxygen. Based on the data under the above working conditions, it is possible to obtain the relationship between the pressure and pressure difference between the cathode and anode of the electrolytic cell - the liquid level of the cathode and anode gas-liquid separator - the hydrogen content in oxygen, and determine the adjustment when adjusting the hydrogen content in oxygen. The pressure, pressure difference and adjustment time provide the basis. The adjustment pressure and pressure difference are adjusted through the opening of the first pressure adjustment valve and the second pressure adjustment valve, so the first pressure adjustment valve and the second pressure can be determined based on the adjustment pressure and pressure difference Adjust the valve opening.

3. Verification of the prediction accuracy of the calibrated model: based on a well-run electrolytic cell, through a given working condition input, verify the consistency between the actual measured electrolytic cell pressure and pressure difference, hydrogen content in oxygen and the model prediction results.

4. During the actual working process, the real-time pressure data measured by the cathode pressure gauge, anode pressure gauge and differential pressure transmitter are summarized to the editable controller and passed to the preset hydrogen content prediction model in oxygen as real-time parameters. Set the predicted value of the hydrogen content prediction model in oxygen, control the opening of the pressure regulating valve, change the trend of hydrogen content in oxygen, and ensure the continuous operation of the system.

In an embodiment, the above step S300, adjusting the pressure on the cathode side and/or the anode side based on the variation trend, includes:

Step S310: judging based on the change trend whether the hydrogen content in oxygen keeps increasing and exceeds the first set value;

Step S320: If it keeps growing continuously and exceeds the first set value, calculate the adjustment parameters on the cathode side and the anode side, and adjust the pressure on the cathode side and/or the anode side according to the adjustment parameters;

Step S330: If the continuous increase is not maintained or the first set value is not exceeded, then the pressure on the cathode side and/or the anode side is not adjusted.

Specifically, the first set value is set according to actual working conditions, and its magnitude is less than or equal to the maximum hydrogen content threshold of 2% in oxygen stipulated in the international water electrolysis hydrogen production standard, that is, the first set value is less than or equal to 2%. Exemplarily, the first set value is 2%. If it is judged according to the change trend that the hydrogen content in oxygen keeps increasing and exceeds the first set value, it means that working according to the current pressure and pressure difference may cause the hydrogen content in oxygen to be too high, so it is necessary to adjust the cathode side and/or anode side. The pressure reduces the hydrogen content in oxygen to avoid the situation where the electrolysis stops due to too high hydrogen content in oxygen, and if it is predicted that the hydrogen content in oxygen will not exceed the first set value, it means that under the current pressure and pressure difference work, it will not cause If the hydrogen content in oxygen is too high, the current differential pressure can continue to work. In the embodiment of the present invention, the hydrogen content in the oxygen is lower than the first set value by adjusting the cathode pressure and the anode pressure, so as to avoid the situation that the hydrogen content in the oxygen is too high.

In one embodiment, the way to adjust the pressure on the cathode side and/or the anode side is to adjust the pressure on the cathode side through the first pressure regulating valve and the second pressure regulating valve respectively arranged at the cathode side outlet and the anode side outlet of the electrolytic cell. and/or the flow rate of gas release on the anode side.

Specifically, when the electrolyzer is combined with variable energy sources for electrolytic hydrogen production, including direct coupling with renewable energy sources, or mutual coupling with renewable energy sources, power grids, and energy storage devices. The randomness, volatility and uncertainty of variable energy will lead to fluctuations in the hydrogen content of oxygen in the electrolyzer, and the fluctuation of hydrogen content in oxygen can be suppressed by adjusting the pressure and pressure difference between the cathode side and the anode side. Based on the way of hydrogen generation in oxygen, it can be seen that the pressure of cathode and anode and the pressure difference have different effects on hydrogen in oxygen. The pressure change has a greater ability to regulate the hydrogen content in oxygen than the pressure difference. The regulating valve adjusts the liquid level difference of the gas-liquid separator, and the adjustable range and response speed are limited. The embodiment of the present invention adjusts the gas release flow rate on the cathode side and/or the anode side, and reduces the pressure by increasing the gas release flow rate or Reducing the gas release flow rate and increasing the pressure can realize rapid regulation of pressure and pressure difference. Specifically, by setting the first pressure regulating valve and the second pressure regulating valve at the cathode and anode outlets of the electrolytic cell to regulate the flow rate of gas release on the cathode side and/or the anode side, the setting of the first pressure regulating valve and the second pressure regulating valve makes The variable range of the liquid level of the gas-liquid separator is widened, and the pressure in the electrolytic cell and the pressure difference on both sides can be adjusted in a short time, and the pressure can be quickly adjusted according to the prediction results of the hydrogen content prediction model in the preset oxygen, so that Improve gas purity.

In an embodiment, the adjustment parameters include adjusting the pressure difference and the adjustment time, and calculating the adjustment parameters on the cathode side and the anode side includes: the pressure and pressure on the cathode side and the anode side under the pre-acquired set working conditions The relationship between the liquid level of the cathode and anode gas-liquid separator and the hydrogen content in oxygen is obtained to adjust the pressure difference and the adjustment time; the way to adjust the pressure on the cathode side and/or the anode side according to the adjustment parameters is: based on the The adjustment parameters are adjusted by adjusting the pressure on the cathode side and/or the anode side through the first pressure regulating valve and the second pressure regulating valve respectively arranged at the cathode side outlet and the anode side outlet of the electrolytic cell. Generally, the adjustment pressure difference ΔP=1000pa is taken, and the adjustment pressure difference represents the value of the pressure on the anode side minus the pressure on the cathode side, and the flow rate of gas release is adjusted by changing the flow rate of the gas release within the adjustment time through the first pressure adjustment valve and the second pressure adjustment valve. The adjustment pressure difference and adjustment time are set based on the relationship between the pressure and pressure difference between the cathode side and the anode side, the liquid level of the cathode and anode gas-liquid separators, and the hydrogen content in oxygen under the set working conditions. The higher the hydrogen content in oxygen under the current pressure difference The greater the adjustment pressure difference, the longer the adjustment time. Exemplarily, when the hydrogen content in oxygen under the current differential pressure is greater than the set adjustment threshold, adjust the differential pressure and the adjustment time according to the gradient, and when the hydrogen content in the oxygen under the current differential pressure is less than the set adjustment threshold, adjust according to ΔP=1000pa The time T=20mim is adjusted.

In one embodiment, adjusting the pressure on the cathode side and/or the anode side according to the adjustment parameters includes: judging whether the adjusted liquid level of the gas-liquid separator exceeds the preset upper and lower limits according to the adjustment parameters; if it does not exceed the preset upper and lower limits, Then adjust the pressure on the cathode side or the anode side according to the adjustment parameters, so that the pressure on the anode side is higher than the pressure on the cathode side; if it exceeds the preset upper and lower limits, reduce the pressure on the cathode side and the anode side at the same time.

Specifically, the preset upper and lower limits are the safe liquid level thresholds required by the gas-liquid separator. According to the relationship between the pressure and pressure difference under the set working conditions, the liquid level of the anode and cathode gas-liquid separators, and the hydrogen content in oxygen, the adjustment parameters Adjust the liquid level corresponding to the pressure difference. If the liquid level does not exceed the preset upper and lower limits, it means that the pressure on the anode side and the cathode side can be adjusted according to the pressure difference. According to the first-level regulation method, the anode side and the cathode side can be adjusted according to the pressure difference If the liquid level exceeds the preset upper and lower limits, it means that adjusting the pressure on the anode side and the cathode side according to the adjusted pressure difference will affect the normal operation of the gas-liquid separator, so choose the second-level adjustment method at this time. At the same time, the pressure on the cathode side and the anode side is reduced. Since the regulation ability of the pressure change on the hydrogen content in oxygen is greater than that of the pressure difference, the hydrogen content in the oxygen can be quickly adjusted at this time.

The embodiment of the present invention adjusts the hydrogen content in oxygen through two different pressure control strategies, adapts to different power supply side fluctuations, broadens the load range of the electrolysis system, prevents the hydrogen content in oxygen from exceeding the set threshold, and can expand the adjustment range. The adjustment method is flexible.

In one embodiment, after the pressure on the cathode side and/or the anode side is adjusted according to the adjustment parameters, the method further includes: predicting whether the hydrogen content in oxygen is lower than the first Two setting values; if it is lower than the second setting value, the pressure on the cathode side and the pressure on the anode side are respectively restored to the pressure before adjustment.

Specifically, the second set value is less than or equal to the first set value, when the predicted hydrogen content in oxygen is lower than the second set value, restore the original pressure on the cathode side and the anode side, when the predicted hydrogen content in oxygen is greater than the first set value When the second set value is reached, continue to adjust the pressure on the cathode side and/or the anode side until the predicted hydrogen content in oxygen reaches a safe range. The embodiment of the present invention can keep the hydrogen content in the oxygen in a safe range during the electrolysis process, and restore the original pressure on the cathode side and the anode side, which has little impact on the electrolysis efficiency.

The following uses a complete embodiment to illustrate the pressure regulation process.

As shown in Figure 2, the internal pressure and pressure difference data of the electrolytic cell are collected in real time, and transmitted to the editable controller for processing. The hydrogen content in oxygen is predicted by the established preset hydrogen content prediction model in oxygen. If the predicted hydrogen in oxygen When the content continues to grow and tends to reach the first set value, the editable controller will calculate the pressure difference ΔP between the cathode side and the anode side required for regulation, and the pressure difference will cause the liquid level of the gas-liquid separator to change (for To ensure safety, the liquid level difference is usually limited to Δh _max = 10. Due to the setting of the first pressure regulating valve and the second pressure regulating valve at the hydrogen and oxygen outlet of the electrolytic cell, the pressure inside the electrolytic cell can be guaranteed to be stable under the condition of a large liquid level difference, so It is no longer limited by the liquid level difference, only the liquid level of the gas-liquid separator is between the required upper and lower limits).

If the liquid level corresponding to the pressure difference is within the safe range, perform primary regulation: change the opening degree ΔX of the first pressure regulating valve and the second pressure regulating valve at the outlet of the electrolytic cell, and adjust the gas flow on both sides so that the pressure on the anode side is higher than that of the cathode side (generally ΔP=1000pa), specifically, the opening degree ΔX of the first pressure regulating valve on the anode side can be reduced to increase the pressure on the anode side, or the opening degree ΔX of the second pressure regulating valve on the cathode side can be increased to reduce The pressure on the cathode side reduces the hydrogen transmembrane convection caused by the pressure difference, inhibits the continued growth of the hydrogen content in the oxygen, and ensures that the system can continue to work.

If the fluctuation range and frequency of the power supply are large, and the liquid level corresponding to the calculated pressure difference ΔP exceeds the preset upper and lower limits required by the gas-liquid separator, perform a secondary regulation: simultaneously adjust the first pressure regulation on the cathode and anode sides The opening degree ΔX of the valve and the second pressure regulating valve adjusts the gas flow on both sides, so that the internal pressure of the electrolytic cell on both sides of the hydrogen and oxygen drops at the same time, and the hydrogen in the oxygen caused by the three parts of liquid mixing, trans-diaphragm gas convection and diffusion is suppressed, so that The hydrogen content in the oxygen can be reduced rapidly, avoiding the violent fluctuation of the power supply causing the hydrogen content in the oxygen to exceed the first set value.

The embodiment of the present invention predicts the hydrogen content in the oxygen in the electrolytic cell in advance by pre-setting the hydrogen content prediction model in the oxygen, which can adjust the gas purity in advance and avoid the shutdown of the electrolysis system; the pressure-based adjustment method for the hydrogen content in the oxygen will not Too much negative impact on the electrolyzer ensures the stability of the system to a great extent, and the suppression effect of adjusting the pressure on hydrogen in oxygen is higher than that of reducing the flow rate; in order to adapt to different power supply side fluctuations, through two different The pressure control strategy adjusts the hydrogen content in oxygen, which broadens the load range of the electrolysis system; the setting of the first pressure regulating valve and the second pressure regulating valve makes the liquid level variable range of the gas-liquid separator wider, and can be used in a short time By adjusting the pressure inside the electrolyzer and the pressure difference on both sides, the pressure can be quickly adjusted according to the prediction results of the preset hydrogen content prediction model in oxygen, thereby improving the gas purity.

The embodiment of the present invention also provides an electrolytic cell gas purity control system, as shown in Figure 3, including a controller, a differential pressure transmitter, a first pressure regulating valve, a second pressure regulating valve, a cathode pressure gauge and an anode pressure gauge , the differential pressure transmitter, the first pressure regulating valve, the second pressure regulating valve, the cathode pressure gauge and the anode pressure gauge are all connected to the controller, and the first pressure regulating valve and the second pressure regulating valve are respectively arranged on the anode of the electrolytic cell The side outlet and the cathode side outlet, the cathode pressure gauge and the anode pressure gauge are respectively set on the anode side and the cathode side of the electrolytic cell, the first pressure regulating valve is used to adjust the pressure on the anode side, and the second pressure regulating valve is used to adjust the pressure on the cathode side, The cathode pressure gauge is used to collect the pressure on the cathode side of the electrolytic cell, the anode pressure gauge is used to collect the pressure on the anode side of the electrolytic cell, and the differential pressure transmitter is used to collect the pressure difference between the cathode side and the anode side of the electrolytic cell. Receive the pressure difference collected by the differential pressure transmitter, the pressure on the cathode side collected by the cathode pressure gauge and the pressure on the anode side collected by the anode pressure gauge, and obtain the pressure in the electrolytic cell according to the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell The change trend of the hydrogen content in oxygen, based on the change trend, the first pressure regulating valve and/or the second pressure regulating valve is controlled to adjust the pressure of the cathode side and/or the anode side.

The gas purity control system of the electrolyzer also includes a hydrogen sensor in oxygen and an oxygen regulating valve set at the gas outlet of the oxygen side, a hydrogen regulating valve set at the gas outlet of the hydrogen side, and an oxygen side gas-liquid separator is also installed on the oxygen side pipeline of the electrolyzer , liquid level transmitter, scrubber, cooler and gas-water separator, the oxygen side pipeline is also equipped with gas-liquid separator, liquid level transmitter, scrubber, cooler and gas-water separator, oxygen side and hydrogen The side liquid level transmitter and the second liquid level transmitter are respectively used to collect the liquid levels of the gas-liquid separator on the oxygen side and the hydrogen side.

Specifically, the controller is an editable controller. In other embodiments, the controller can also be a central processing unit (Central Processing Unit, CPU), a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), Field-Programmable Gate Array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components and other chips, or a combination of the above-mentioned types of chips.

The gas purity control system of the electrolyzer in the embodiment of the present invention improves the error tolerance rate when the electrolyzer is coupled with the variable energy source based on the change trend prediction and pressure control strategy, predicts the hydrogen content in oxygen in advance and performs corresponding control, and improves the gas purity. Avoid frequent forced shutdown of the system and widen the working load range of the electrolyzer. The setting of the pressure regulating valve widens the variable range of the liquid level of the gas-liquid separator, which can adjust the pressure in the electrolytic cell and the pressure difference on both sides in a short time, and can realize rapid regulation of the pressure according to the model prediction results, thereby improving the gas purity.

The embodiment of the present invention also provides an electrolyzer gas purity control device, as shown in Figure 4, comprising:

The acquiring module 401 is configured to acquire the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell; for details, please refer to the corresponding part of the method embodiment above, which will not be repeated here.

The prediction module 402 is used to obtain the change trend of the hydrogen content in the oxygen in the electrolytic cell according to the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell; for details, refer to the corresponding part of the above method embodiment, which will not be repeated here.

An adjustment module 403, configured to adjust the pressure on the cathode side and/or the anode side based on the variation trend. For specific content, refer to the corresponding part of the foregoing method embodiment, and details are not repeated here.

The gas purity control device of the electrolyzer according to the embodiment of the present invention obtains the pressure and pressure difference between the cathode side and the anode side of the electrolyzer, and then obtains the change of the hydrogen content in the oxygen in the electrolyzer according to the pressure and pressure difference between the cathode side and the anode side Trend, adjust the pressure on the cathode side and/or anode side based on the change trend, and predict the hydrogen content in the oxygen in the electrolytic cell through the change trend of the hydrogen content in the oxygen, so as to adjust the pressure on the cathode side and/or the anode side in time to reduce the oxygen content. Hydrogen content, to avoid the frequent shutdown of the equipment caused by the hydrogen content in the oxygen in the electrolyzer exceeding the safe range, and improve the system's ability to control the hydrogen content in oxygen and the response speed.

The embodiment of the present invention also provides a computer-readable storage medium, as shown in FIG. 5 , on which a computer program 13 is stored. When the instruction is executed by a processor, the steps of the method for controlling the gas purity of the electrolyzer in the above-mentioned embodiment are realized. The storage medium also stores audio and video stream data, feature frame data, interaction request signaling, encrypted data, and preset data sizes. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a flash memory (Flash Memory), a hard disk (Hard DiskDrive, abbreviated : HDD) or a solid-state hard drive (Solid-State Drive, SSD), etc.; the storage medium may also include a combination of the above-mentioned types of memories. Those skilled in the art can understand that all or part of the processes in the method of the above-mentioned embodiments can be completed by instructing related hardware through a computer program. The computer program 13 can be stored in a computer-readable storage medium. During execution, it may include the processes of the embodiments of the above-mentioned methods. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a flash memory (Flash Memory), a hard disk (Hard Disk Drive, Abbreviation: HDD) or solid-state drive (Solid-State Drive, SSD), etc.; the storage medium may also include a combination of the above-mentioned types of storage.

Above, the above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be applied to the foregoing embodiments The technical solutions described in the examples are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (10)

1. A method for controlling the purity of electrolyzer gas, characterized in that, comprising: Obtain the pressure and differential pressure on the cathode and anode sides of the electrolysis cell; Obtaining the change trend of hydrogen content in oxygen in the electrolytic cell according to the pressure and pressure difference between the cathode side and the anode side; adjusting the pressure on the cathode side and/or the anode side based on the variation trend; Wherein, according to the pressure difference between the cathode side and the anode side, obtaining the change trend of the hydrogen content in the oxygen in the electrolytic cell includes: inputting the pressure and the pressure difference between the cathode side and the anode side of the electrolytic cell to a pre-set Setting up a prediction model of hydrogen content in oxygen; obtaining the change trend of hydrogen content in oxygen through the preset prediction model of hydrogen content in oxygen; The process of constructing the preset hydrogen content prediction model in oxygen includes: constructing an initial hydrogen content prediction model in oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convection flow of dissolved hydrogen in the electrolyte; The dynamic impurity accumulation process and the initial hydrogen content prediction model in oxygen construct the preset hydrogen content prediction model. 2. The electrolyzer gas purity control method according to claim 1, characterized in that, adjusting the pressure on the cathode side and/or the anode side based on the variation trend comprises: judging based on the change trend whether the hydrogen content in the oxygen keeps increasing and exceeds the first set value; If it keeps growing continuously and exceeds the first set value, then calculate the adjustment parameters on the cathode side and the anode side, and adjust the pressure on the cathode side and/or the anode side according to the adjustment parameters; If the continuous increase is not maintained or the first set value is not exceeded, the pressure on the cathode side and/or the anode side is not adjusted. 3. The electrolyzer gas purity control method according to claim 2, characterized in that, adjusting the pressure on the cathode side and/or the anode side according to the adjustment parameter comprises: judging according to the adjustment parameters whether the adjusted liquid level of the gas-liquid separator exceeds the preset upper and lower limits; If it does not exceed the preset upper and lower limits, then adjust the pressure on the cathode side or the anode side according to the adjustment parameter, so that the pressure on the anode side is higher than the pressure on the cathode side; If the preset upper and lower limits are exceeded, the pressure on the cathode side and the anode side are simultaneously reduced. 4. The electrolyzer gas purity control method according to claim 2, characterized in that, after adjusting the pressure on the cathode side and/or the anode side according to the adjustment parameters, it also includes: predicting whether the hydrogen content in the oxygen is lower than a second set value according to the adjusted pressure and pressure difference between the cathode side and the anode side; If it is lower than the second set value, the pressure on the cathode side and the pressure on the anode side are respectively restored to the pressures before adjustment. 5. The electrolyzer gas purity control method according to claim 2, characterized in that, the adjustment parameters include adjustment pressure difference and adjustment time, and the adjustment parameters of the calculation of the cathode side and the anode side include: Acquire the adjusted pressure difference and the adjusted time according to the pre-acquired relationship between the pressure and pressure difference between the cathode side and the anode side, the liquid level of the gas-liquid separator, and the hydrogen content in oxygen under the pre-acquired set working conditions; The way to adjust the pressure on the cathode side and/or the anode side according to the adjustment parameters is as follows: Based on the regulation parameters, the pressure on the cathode side and/or the anode side is regulated by a first pressure regulating valve and a second pressure regulating valve provided respectively at the cathode side outlet and the anode side outlet of the electrolytic cell. 6. electrolyzer gas purity control method according to claim 1 is characterized in that, builds hydrogen content prediction model in the initial oxygen according to the gas mixing flux of the hydrogen dissolved in the electrolytic solution, the hydrogen diffusion flux and the hydrogen convective flow Before, also include: Obtain gas mixing flux according to the concentration of hydrogen on the cathode side and the flow rate of the electrolyte; The hydrogen diffusion flux is obtained according to the effective diffusion coefficient of hydrogen passing through the diaphragm, the thickness of the diaphragm and the concentration difference of hydrogen; Hydrogen convective flow was obtained from the pressure difference between the cathode and anode sides, the permeability of the diaphragm, the kinetic viscosity of the electrolyte, the solubility of hydrogen in the catholyte, the pressure on the cathode side, and the thickness of the diaphragm. 7. The electrolyzer gas purity control method according to claim 1, characterized in that, the mode of regulating the pressure on the cathode side and/or the anode side is by being respectively arranged at the cathode side outlet and the anode side outlet of the electrolyzer A first pressure regulating valve and a second pressure regulating valve at the outlet of the anode side regulate the flow rate of gas release on the cathode side and/or on the anode side. 8. An electrolyzer gas purity control system, characterized in that it comprises a controller, a differential pressure transmitter, a first pressure regulating valve, a second pressure regulating valve, a cathode pressure gauge and an anode pressure gauge, the differential pressure transmitter The transmitter, the first pressure regulating valve, the second pressure regulating valve, the cathode pressure gauge and the anode pressure gauge are all connected to the controller, and the first pressure regulating valve and the second pressure regulating valve are respectively arranged on the anode of the electrolytic cell Side outlet and cathode side outlet, the cathode pressure gauge and anode pressure gauge are respectively set on the anode side and the cathode side of the electrolytic cell, the first pressure regulating valve is used to adjust the pressure on the anode side, and the second pressure regulating valve is used to To adjust the pressure on the cathode side, the cathode pressure gauge is used to collect the pressure on the cathode side of the electrolyzer, the anode pressure gauge is used to collect the pressure on the anode side of the electrolyzer, and the differential pressure transmitter is used to collect the pressure on the anode side of the electrolyzer The pressure difference between the cathode side and the anode side of the controller is used to receive the pressure difference collected by the differential pressure transmitter, the pressure on the cathode side collected by the cathode pressure gauge and the pressure on the anode side collected by the anode pressure gauge Pressure, according to the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell to obtain the change trend of the hydrogen content in the oxygen in the electrolytic cell, based on the change trend to control the first pressure regulating valve and/or the second pressure regulating valve. The adjustment of the pressure on the cathode side and/or the anode side, wherein, according to the pressure difference between the cathode side and the anode side, the change trend of the hydrogen content in the oxygen in the electrolyzer is obtained, including: the cathode of the electrolyzer The pressure and pressure difference on the side and the anode side are input to the preset prediction model of hydrogen content in oxygen; the change trend of hydrogen content in oxygen is obtained through the preset prediction model of hydrogen content in oxygen; The process of constructing the preset hydrogen content prediction model in oxygen includes: constructing an initial hydrogen content prediction model in oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convection flow of dissolved hydrogen in the electrolyte; The dynamic impurity accumulation process and the hydrogen content prediction model in the initial oxygen construct the preset hydrogen content prediction model in oxygen; The gas purity control system of the electrolyzer also includes a hydrogen sensor in oxygen and an oxygen regulating valve set at the gas outlet of the oxygen side, a hydrogen regulating valve set at the gas outlet of the hydrogen side, and an oxygen side gas-liquid separator is also installed on the oxygen side pipeline of the electrolyzer , liquid level transmitter, scrubber, cooler and gas-water separator, and the hydrogen side gas-liquid separator, liquid level transmitter, scrubber, cooler and gas-water separator are also installed on the oxygen side pipeline. The pressure regulating valve and the second pressure regulating valve are respectively arranged at the outlet of the anode side and the cathode side of the electrolytic cell. One end of the first pressure regulating valve is connected to the anode side of the electrolytic cell, and the other end is connected to the gas-liquid separator on the oxygen side. One end of the pressure regulating valve is connected to the cathode side of the electrolytic cell, and the other end is connected to the gas-liquid separator on the hydrogen side. 9. An electrolyzer gas purity control device, characterized in that it comprises: An acquisition module, configured to acquire the pressure and pressure difference between the cathode side and the anode side of the electrolytic cell; A prediction module for obtaining a change trend of hydrogen content in oxygen in the electrolyzer according to the pressure and pressure difference between the cathode side and the anode side of the electrolyzer; A regulation module for regulating the pressure on the cathode side and/or the anode side based on said variation trend; Wherein, according to the pressure difference between the cathode side and the anode side, obtaining the change trend of the hydrogen content in the oxygen in the electrolytic cell includes: inputting the pressure and the pressure difference between the cathode side and the anode side of the electrolytic cell to a pre-set Setting up a prediction model of hydrogen content in oxygen; obtaining the change trend of hydrogen content in oxygen through the preset prediction model of hydrogen content in oxygen; The process of constructing the preset hydrogen content prediction model in oxygen includes: constructing an initial hydrogen content prediction model in oxygen according to the gas mixing flux, hydrogen diffusion flux and hydrogen convection flow of dissolved hydrogen in the electrolyte; The dynamic impurity accumulation process and the initial hydrogen content prediction model in oxygen construct the preset hydrogen content prediction model. 10. A computer-readable storage medium, characterized in that, the computer-readable storage medium stores computer instructions, and the computer instructions are used to make the computer execute the electrolysis method according to any one of claims 1 to 7. Tank gas purity control method.