Rapid cold start alkaline electrolysis hydrogen production system and method

Abstract

The invention discloses a rapid cold start alkaline electrolysis hydrogen production system and method, and relates to the technical field of water electrolysis hydrogen production. The rapid cold start alkaline electrolysis hydrogen production system comprises an alkaline liquor electrolysis unit, a waste heat recovery heat exchanger, an alkaline liquor storage tank, a heat storage water tank, a first heat exchange pipeline, a second heat exchange pipeline, a first waste heat recovery pipeline, a second waste heat recovery pipeline, a compressor and a throttling valve. The first waste heat recovery pipeline and the second waste heat recovery pipeline are communicated between the alkali liquor electrolysis unit and the waste heat recovery heat exchanger; the waste heat recovery heat exchanger is communicated with the alkali liquor storage tank and the heat storage water tank; the heat storage water tank is communicated with the alkali liquor electrolysis unit; the first heat exchange pipeline and the second heat exchange pipeline are both connected between the alkali liquor storage tank and the heat storage water tank; the compressor is fixedly mounted on the first heat exchange pipeline; and the throttle valve is fixedly mounted on the second heat exchange pipeline. The method has the beneficial effects that the cold start time can be shortened, the energy utilization efficiency is optimized, and the water and electricity safety of equipment is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by water electrolysis, and more particularly to a rapid cold-start alkaline electrolysis hydrogen production system and method. Background Art

[0002] Alkaline water electrolysis is the main method of commercial hydrogen production by electrolysis at present and in the future. It has the significant advantages of high scalability and relatively low equipment cost. However, conventional alkaline water electrolysis is limited by the disadvantages of high power consumption and low current density, which makes the equipment bulky, large in size, and slow to start. Typically, industrial alkaline water electrolyzers need to operate at 70-95°C to ensure that the operating current density reaches the conventional range of 2000-4000A / m2. When operating from room temperature, it usually takes 2-5 hours to heat up to 70-95°C to reach the rated electrolysis hydrogen production current density. Excessive heating and startup time not only leads to a low proportion of the effective hydrogen production time, but also the relatively low purity of hydrogen at the initial low current density (hundreds to 2000A / m2), resulting in excessive energy and material losses. This is particularly prominent in the scenario of hydrogen production by electrolysis using renewable electricity.

[0003] The prior art discloses a self-heating start water electrolysis hydrogen production system and its operation method. This technology realizes rapid heating of the electrolyzer by winding a heating tube on the electrolyte buffer tank and also includes a catalytic burner to provide a heat source. However, the need for a high-temperature catalytic burner increases the safety risk of the electrolysis hydrogen production equipment. The prior art also discloses a water electrolysis hydrogen production system with the function of heating the electrolyte. By providing a heating device and a temperature sensor for heating the electrolyte, the cold start time of the hydrogen production system is greatly shortened. In addition, the prior art also discloses a method for accelerating the electrolysis hydrogen production equipment, in which the heat generated inside the hydrogen production power supply is transferred to the electrolyzer through a water heat radiator to heat the electrolyzer, thereby making full use of the heat energy generated by the power supply and shortening the start-up time of the electrolyzer. In the above technology, whether a heating device is used to heat the electrolyte or the heat of the electrolysis power supply is used for heat exchange heating, it is easy to cause increased energy consumption or hidden dangers to the water and electricity safety of the equipment.

[0004] To this end, the present invention provides an alkaline electrolysis hydrogen production system with rapid cold start, which can shorten the cold start time, optimize energy utilization efficiency, and ensure the water and electricity safety of the equipment. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides an alkaline electrolysis hydrogen production system with rapid cold start, which can shorten the cold start time, optimize energy utilization efficiency, and ensure the water and electricity safety of the equipment.

[0006] The technical solution adopted by the present invention to solve its technical problems is: a rapid cold start alkaline electrolysis hydrogen production system, the improvement of which is that the rapid cold start alkaline electrolysis hydrogen production system includes an alkali solution electrolysis unit, a waste heat recovery heat exchanger, an alkali solution storage tank, a hot water storage tank, a first heat exchange pipe, a second heat exchange pipe, a first waste heat recovery pipe, a second waste heat recovery pipe, a compressor and a throttle valve; the first waste heat recovery pipe and the second waste heat recovery pipe are connected between the alkali solution electrolysis unit and the waste heat recovery heat exchanger; the waste heat recovery heat exchanger is connected to the alkali solution storage tank and the hot water storage tank; the hot water storage tank is connected to the alkali solution electrolysis unit; the first heat exchange pipe and the second heat exchange pipe are both connected between the alkali solution storage tank and the hot water storage tank; the compressor is fixedly installed on the first heat exchange pipe; the throttle valve is fixedly installed on the second heat exchange pipe.

[0007] In the above structure, the alkali liquid electrolysis unit includes an alkali liquid delivery pipeline, an alkali liquid circulation pump, an alkali liquid delivery valve, an alkaline electrolytic cell, an oxygen separation mechanism, and a hydrogen separation mechanism; the alkali liquid delivery pipeline is connected between the alkaline electrolytic cell and the alkali liquid storage tank; the alkali liquid circulation pump and the alkali liquid delivery valve are both fixedly installed on the alkali liquid delivery pipeline, and the alkali liquid delivery valve is close to the alkaline electrolytic cell, and the alkali liquid circulation pump is close to the alkali liquid storage tank; the oxygen separation mechanism and the hydrogen separation mechanism are both connected to the alkaline electrolytic cell.

[0008] In the above structure, the oxygen separation mechanism includes a first separation liquid storage tank, a first gas-liquid separator, a first cooling water input pipe, a first cooling water output pipe, an oxygen output pipe, and an oxygen outlet valve; the first separation liquid storage tank is connected between the alkaline electrolytic cell, the first waste heat recovery pipe, and the first gas-liquid separator; the first gas-liquid separator is connected to the first cooling water input pipe, the first cooling water output pipe, and the oxygen output pipe; and the oxygen outlet valve is fixedly mounted on the oxygen output pipe.

[0009] In the above structure, the hydrogen separation mechanism includes a second separation liquid storage tank, a second gas-liquid separator, a second cooling water input pipe, a second cooling water output pipe, a hydrogen output pipe, a hydrogen outlet valve and a water supply pipe; the second separation liquid storage tank is connected between the alkaline electrolytic cell, the second waste heat recovery pipe and the second gas-liquid separator; the second gas-liquid separator is connected to the second cooling water input pipe, the second cooling water output pipe, the hydrogen output pipe and the hydrogen output pipe; the hydrogen outlet valve is fixedly installed on the hydrogen output pipe.

[0010] In the above structure, the rapid cold start alkaline electrolysis hydrogen production system also includes a third heat exchange pipe, a hot water storage tank circulation pump and a hot water storage tank heat exchange valve; the third heat exchange pipe is connected between the hot water storage tank and the waste heat recovery heat exchanger; the heat storage circulation pump and the hot water storage tank heat exchange valve are both fixedly installed on the third heat exchange pipe, and the heat storage circulation pump is located between the hot water storage tank and the heat storage vertical heat exchange valve.

[0011] In the above structure, the rapid cold start alkaline electrolysis hydrogen production system also includes a third cooling water input pipe, a cooling water inlet valve and a first cooling water three-way valve; the third cooling water input pipe is connected to the third heat exchange pipe; the cooling water inlet valve and the first cooling water three-way valve are both fixedly installed on the third cooling water input pipe, and the first cooling water three-way valve is located at the connection point between the third cooling water input pipe and the third heat exchange pipe.

[0012] In the above structure, the rapid cold start alkaline electrolysis hydrogen production system also includes a fourth heat exchange pipe, a third cooling water output pipe, a second cooling water three-way valve and a cooling water outlet valve; the fourth heat exchange pipe is connected between the waste heat recovery heat exchanger and the hot water storage tank; the cooling water output pipe is connected to the fourth heat exchange pipe; the second cooling water three-way valve is fixedly installed at the connection point between the cooling water output pipe and the fourth heat exchange pipe; the cooling water outlet valve is fixedly installed on the cooling water output pipe.

[0013] A rapid cold start alkaline electrolysis hydrogen production method is applied to the rapid cold start alkaline electrolysis hydrogen production system described above, wherein the rapid cold start alkaline electrolysis hydrogen production method comprises the following steps:

[0014] The hot water storage tank exchanges heat with the alkali solution in the alkali solution storage tank through the refrigerant in the first heat exchange pipe and the second heat exchange pipe to obtain alkali solution with a temperature suitable for electrolysis;

[0015] The alkali solution with temperature adapted for electrolysis enters the alkaline electrolysis cell through the alkali solution delivery pipeline for electrolysis to obtain wet hydrogen and wet oxygen mixed with the alkali solution;

[0016] The wet oxygen enters the oxygen separation mechanism to separate the alkali solution to obtain pure oxygen and output it through the oxygen output pipeline; the wet hydrogen enters the hydrogen separation mechanism to separate the alkali solution to obtain pure hydrogen and output it through the hydrogen output pipeline;

[0017] The alkali liquid separated from the wet oxygen and wet hydrogen is recovered to the alkali liquid storage tank after heat exchange with the circulating water flowing in from the hot water storage tank in the waste heat recovery heat exchanger, and the circulating water after heat exchange flows back to the hot water storage tank.

[0018] Furthermore, the specific method of exchanging heat between the refrigerant and the alkali liquid in the alkali liquid storage tank is as follows: when the alkaline electrolytic cell is started, the liquid refrigerant absorbs heat in the hot water storage tank and evaporates into a gaseous refrigerant, and the gaseous refrigerant is transported to the alkali liquid storage tank by the first heat exchange pipe, and the compressor further heats and pressurizes the gaseous refrigerant during the transportation process; the further heated and pressurized gaseous refrigerant releases heat in the alkali liquid storage tank to heat the alkali liquid; after the heat release is completed, the gaseous refrigerant becomes a liquid refrigerant, and the liquid refrigerant is depressurized through the throttle valve and then transported back to the hot water storage tank by the second heat exchange pipe.

[0019] The beneficial effects of the present invention are as follows: the present invention can recover the heat generated by electrolysis to the hot water storage tank through the waste heat recovery heat exchanger, and can realize heat exchange between the hot water storage tank and the alkali solution storage tank through the first heat exchange pipe and the second heat exchange pipe to realize heating of the alkali solution. In this process, the demand for external heating when the alkaline electrolysis hydrogen production system is started can be reduced, thereby shortening the cold start time, and heating the alkali solution by recycling the heat generated by electrolysis can improve the energy utilization efficiency; in addition, by recycling the heat to heat the alkali solution, it can avoid equipment damage caused by excessive heat or pressure, so as to ensure the water and electricity safety of the equipment during the electrolysis process; therefore, the present invention can shorten the cold start time, optimize the energy utilization efficiency, and ensure the water and electricity safety of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the overall structure of a rapid cold start alkaline electrolysis hydrogen production system of the present invention;

[0021] Figure 2 The figure is an overall flow chart of a rapid cold start alkaline electrolysis hydrogen production method of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below with reference to the accompanying drawings and examples.

[0023] The following will clearly and completely describe the concept, specific structure and technical effects of the present invention in combination with the embodiments and drawings, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. In addition, all the connection / connection relationships involved in the patent do not refer to the direct connection of components, but refer to the fact that a better connection structure can be formed by adding or reducing connection accessories according to the specific implementation situation. The various technical features in the invention can be combined interactively without conflicting with each other.

[0024] Reference Figure 1As shown, the present invention discloses an alkaline electrolysis hydrogen production system with rapid cold start, which includes an alkali solution electrolysis unit, a waste heat recovery heat exchanger 4, an alkali solution storage tank 2, a hot water storage tank 1, a first heat exchange pipe 6, a second heat exchange pipe 5, a first waste heat recovery pipe 9, a second waste heat recovery pipe 10, a compressor 7 and a throttle valve 8; the first waste heat recovery pipe 9 and the second waste heat recovery pipe 10 are connected between the alkali solution electrolysis unit and the waste heat recovery heat exchanger 4; the waste heat recovery heat exchanger 4 is connected with the alkali solution storage tank 2 and the hot water storage tank 1; the hot water storage tank 1 is connected with the alkali solution electrolysis unit; the first heat exchange pipe 6 and the second heat exchange pipe 5 are both connected between the alkali solution storage tank 2 and the hot water storage tank 1; the compressor 7 is fixedly installed on the first heat exchange pipe 6; the throttle valve 8 is fixedly installed on the second heat exchange pipe 5.

[0025] It should be noted that, in this embodiment, the alkali liquid electrolysis unit uses alkali liquid (such as potassium hydroxide solution) as an electrolyte to decompose water in the electrolytic cell 3 through the action of electric current to produce hydrogen and oxygen, and recovers the alkali liquid in the hydrogen and oxygen and the heat generated during the electrolysis process; the waste heat recovery heat exchanger 4 is used to recover the heat generated during the electrolysis process, and stores the recovered heat in the hot water storage tank 1 and transports the alkali liquid recovered from the hydrogen and oxygen to the alkali liquid storage tank 2; the alkali liquid storage tank 2 is used to store alkali liquid to provide alkali liquid for the electrolysis reaction; the hot water storage tank 1 is used to provide heat for the heating of the alkali liquid, specifically through the heat absorption and heat release process of the refrigerant in the coil of the hot water storage tank 1 to achieve the alkali liquid The first heat exchange pipe 6 and the second heat exchange pipe 5 are used to transport the heat in the hot water storage tank 1 to the alkali liquid storage tank 2 (that is, the refrigerant after absorbing heat is transported to the coil in the alkali liquid storage tank 2 to release heat) to heat the alkali liquid in the alkali liquid storage tank 2; the first waste heat recovery pipe 9 and the second waste heat recovery pipe 10 are used to transport the heat generated in the electrolysis and the alkali liquid recovered from the hydrogen and oxygen to the waste heat recovery heat exchanger 4; the compressor 7 is used to further heat and pressurize the refrigerant after absorbing heat, so that the temperature of the refrigerant can meet the heating requirement of the alkali liquid in the alkali liquid storage tank 2; the throttle valve 8 is used to depressurize the refrigerant that has released heat, so that the refrigerant that has released heat can flow back to the heat storage tank In the coil in the water tank 1; when the present invention is specifically implemented, the alkaline electrolysis hydrogen production system with rapid cold start will successively go through four stages: heating mode, electrolysis mode, heat storage mode and heat dissipation mode. Specifically, in the heating mode, first, the alkali liquid electrolysis unit needs to be turned on. At this time, the refrigerant in the coil of the water storage tank 1 begins to absorb heat and evaporate, and the liquid refrigerant becomes a gaseous refrigerant; then, the gaseous refrigerant enters the first heat exchange pipe 6, and after being heated and pressurized by the compressor 7, it enters the coil in the alkali liquid storage tank 2, and releases heat in the coil to achieve heat exchange with the alkali liquid in the alkali liquid storage tank 2; then, when the gaseous refrigerant has completed heat release, the gaseous refrigerant is converted back into liquid refrigerant. At this time, the liquid refrigerant enters the second heat exchange pipe 5, passes through the throttle valve 8 for pressure relief, and then returns to the coil in the hot water storage tank 1; when the alkali liquid in the alkali liquid storage tank 2 is heated to a temperature that meets the electrolysis temperature, the alkaline electrolysis hydrogen production system with rapid cold start enters the electrolysis mode. In this mode, the heated alkali liquid will be transported to the alkali liquid electrolysis unit for electrolysis. When the electrolysis is completed, hydrogen and oxygen will be produced. Because heat is generated in the electrolysis process and the generated oxygen and hydrogen contain alkali liquid, the alkali liquid electrolysis unit will recover the heat in the electrolysis process and the alkali liquid contained in the oxygen and hydrogen, and transport them to the waste heat recovery heat exchanger 4 through the first waste heat recovery pipe 9 and the second waste heat recovery pipe 10;When the heat from the electrolysis process and the alkali liquid contained in the oxygen and hydrogen enter the waste heat recovery heat exchanger 4, the alkaline electrolysis hydrogen production system with rapid cold start enters the heat storage mode. During this process, the circulating water in the hot water storage tank 1 enters the waste heat recovery heat exchanger 4 to absorb the heat generated in the electrolysis process in the form of heat exchange with the recovered alkali liquid. When the heat exchange is completed, the circulating water returns to the hot water storage tank 1 to realize the recovery of the heat generated by electrolysis, and the alkali liquid that has completed the heat exchange will return to the alkali liquid storage tank 2; when the above process is completed, the hot water storage tank 1 has absorbed the heat from the electrolysis process, and the temperature inside the hot water storage tank 1 may be close to the alkali liquid temperature. At this time, the alkaline electrolysis hydrogen production system with rapid cold start enters the heat release mode. During this process, the heat exchange between the hot water storage tank 1 and the waste heat recovery heat exchanger will be closed. A heat pipe is used, and cooling water is passed into the waste heat recovery pipe heat exchanger to remove the heat in the recovered alkali solution and discharge it, thereby preventing the temperature in the hot water storage tank 1 and the temperature of the alkali solution in the alkali solution storage tank 2 from being too high, thereby achieving temperature controllable control during the hydrogen production process of the alkaline electrolysis hydrogen production system with rapid cold start. In the above process, this embodiment can reduce the need for external heating when the alkaline electrolysis hydrogen production system is started, thereby shortening the cold start time, and by recycling the heat generated by electrolysis to heat the alkali solution, energy utilization efficiency can be improved. In addition, by recycling heat to heat the alkali solution, equipment damage caused by excessive heat or pressure can be avoided, thereby ensuring the water and electricity safety of the equipment during the electrolysis process. Therefore, this embodiment can shorten the cold start time, optimize energy utilization efficiency, and ensure the water and electricity safety of the equipment.

[0026] Continue to refer to Figure 1As shown, the alkali liquid electrolysis unit includes an alkali liquid delivery pipeline 23, an alkali liquid circulation pump 24, an alkali liquid delivery valve 25, an alkaline electrolytic cell 3, an oxygen separation mechanism and a hydrogen separation mechanism; the alkali liquid delivery pipeline 23 is connected between the alkaline electrolytic cell 3 and the alkali liquid storage tank 2; the alkali liquid circulation pump 24 and the alkali liquid delivery valve 25 are both fixedly installed on the alkali liquid delivery pipeline 23, and the alkali liquid delivery valve 25 is close to the alkaline electrolytic cell 3, and the alkali liquid circulation pump 24 is close to the alkali liquid storage tank 2; the oxygen separation mechanism and the hydrogen separation mechanism are both connected to the alkaline electrolytic cell 3; the oxygen separation mechanism includes a first separation liquid storage tank 13, a first gas-liquid separator 14, a first cooling water input pipeline 11, a first cooling water output pipeline 12, an oxygen output pipeline 16 and an oxygen outlet valve 15; the first separation liquid storage tank 13 is connected to the alkaline electrolytic cell 3, the first waste heat recovery pipeline 9 and the first a gas-liquid separator 14; the first gas-liquid separator 14 is connected to the first cooling water input pipeline 11, the first cooling water output pipeline 12 and the oxygen output pipeline 16; the oxygen outlet valve 15 is fixedly installed on the oxygen output pipeline 16; the hydrogen separation mechanism includes a second separation liquid storage tank 19, a second gas-liquid separator 20, a second cooling water input pipeline 17, a second cooling water output pipeline 18, a hydrogen output pipeline 22, a hydrogen outlet valve 21 and a water supply pipeline 36; the second separation liquid storage tank 19 is connected between the alkaline electrolytic cell 3, the second waste heat recovery pipeline 10 and the second gas-liquid separator 20; the second gas-liquid separator 20 is connected to the second cooling water input pipeline 17, the second cooling water output pipeline 18, the hydrogen output pipeline 22 and the hydrogen output pipeline 22; the hydrogen outlet valve 21 is fixedly installed on the hydrogen output pipeline 22.

[0027] It should be noted that, in the present embodiment, the alkali liquid delivery pipeline 23, the alkali liquid circulation pump 24, and the alkali liquid delivery valve 25 are designed to transport the alkali liquid after heating from the alkali liquid storage tank 2 to the alkaline electrolytic cell 3; the alkaline electrolytic cell 3 is used to electrolyze the alkali liquid, thereby generating hydrogen and oxygen containing the alkali liquid, and the oxygen containing the alkali liquid enters the oxygen separation mechanism, and the hydrogen containing the alkali liquid enters the hydrogen separation mechanism; further, the oxygen containing the alkali liquid enters the first gas-liquid separator 14 to separate the alkali liquid and pure oxygen, wherein the pure oxygen is discharged through the oxygen output pipeline 16 and the oxygen outlet valve 15, and the alkali liquid enters the first separation liquid storage tank 13 and enters the waste heat recovery heat exchanger 4 through the first waste heat recovery pipeline 9; and in the process of separating the alkali liquid and pure oxygen, the first cooling water input pipeline 16 is used to input the first cooling water input pipeline 14 to separate the alkali liquid and pure oxygen. 1. Cooling water is input to take away part of the heat in the alkali liquid and is discharged through the first cooling water output pipe 12 to prevent the temperature in the first gas-liquid separator 14 from being too high and causing equipment failure; similarly, the hydrogen containing the alkali liquid enters the second enterprise to separate the alkali liquid and pure hydrogen, wherein the pure hydrogen is discharged through the hydrogen output pipe 22 and the hydrogen outlet valve 21, and the alkali liquid enters the second separated liquid storage tank 19 and enters the waste heat recovery heat exchanger 4 through the second waste heat recovery pipe 10. In the process of separating the alkali liquid and pure hydrogen, cooling water is input through the second cooling water input pipe 17 to take away part of the heat in the alkali liquid and is discharged through the second cooling water output pipe 18 to prevent the temperature in the second gas-liquid separator 20 from being too high and causing equipment failure; in addition, the water supply pipe 36 is used to replenish the water consumed in the electrolysis process.

[0028] Continue to refer to Figure 1As shown, the rapid cold start alkaline electrolysis hydrogen production system also includes a third heat exchange pipe 29, a hot water storage tank circulation pump 31, a hot water storage tank heat exchange valve 32, a third cooling water input pipe 34, a cooling water inlet valve 33, a first cooling water three-way valve 35, a fourth heat exchange pipe 30, a third cooling water output pipe 27, a second cooling water three-way valve 28 and a cooling water outlet valve 26; the third heat exchange pipe 29 is connected between the hot water storage tank 1 and the waste heat recovery heat exchanger 4; the heat storage circulation pump and the hot water storage tank heat exchange valve 32 are both fixedly installed on the third heat exchange pipe 29, and the heat storage circulation pump is located between the hot water storage tank 1 and the heat storage vertical heat exchange valve; the The third cooling water input pipe 34 is connected to the third heat exchange pipe 29; the cooling water inlet valve 33 and the first cooling water three-way valve 35 are both fixedly installed on the third cooling water input pipe 34, and the first cooling water three-way valve 35 is located at the connection point between the third cooling water input pipe 34 and the third heat exchange pipe 29; the fourth heat exchange pipe 30 is connected between the waste heat recovery heat exchanger 4 and the hot water storage tank 1; the cooling water output pipe is connected to the fourth heat exchange pipe 30; the second cooling water three-way valve 28 is fixedly installed at the connection point between the cooling water output pipe and the fourth heat exchange pipe 30; the cooling water outlet valve 26 is fixedly installed on the cooling water output pipe.

[0029] It should be noted that, in the present embodiment, the third heat exchange pipe 29, the first cooling water three-way valve 35, the second cooling water three-way valve 28, the hot water storage tank circulation pump 31 and the fourth heat exchange pipe 30 are designed to adapt to the heat storage mode of the alkaline electrolysis hydrogen production system with rapid cold start. Specifically, when the alkaline electrolysis hydrogen production system with rapid cold start enters the heat storage mode, the hot water storage tank circulation pump 31 drives the circulating water in the hot water storage tank 1 through the third heat exchange pipe 29 and the first cooling water three-way valve 35 to enter the waste heat recovery device for heat exchange with the recovered alkali solution. After the heat exchange is completed, the circulating water returns to the hot water storage tank 1 through the fourth heat exchange pipe 30 and the second cooling water three-way valve 28 to realize the recovery of the heat generated by the electrolysis process; the third cooling water input pipe 34 and the third cooling water output pipe 27 are designed to adapt to the heat dissipation mode of the alkaline electrolysis hydrogen production system with rapid cold start. Specifically, when When the alkaline electrolysis hydrogen production system with rapid cold start enters the heat dissipation mode, the alkaline electrolysis hydrogen production system with rapid cold start introduces cooling water into the waste heat recovery pipe heat exchanger through the third cooling water input pipe 34 to take away the heat in the recovered alkali solution and discharge it from the third cooling water output pipe 27 to prevent the temperature in the hot water storage tank 1 and the temperature of the alkali solution in the alkali solution storage tank 2 from being too high, thereby realizing the temperature controllable of the alkaline electrolysis hydrogen production system with rapid cold start during the hydrogen production process; the design of the hot water storage tank heat exchange valve 32, the cooling water inlet valve 33 and the cooling water outlet valve 26 is used to adapt to the switching between the heat storage mode and the heat dissipation mode, that is, when in the heat storage mode, the hot water storage tank heat exchange valve 32 is opened, and the cooling water inlet valve 33 and the cooling water outlet valve 26 are closed; when in the heat dissipation mode, the hot water storage tank heat exchange valve 32 is closed, and the cooling water inlet valve 33 and the cooling water outlet valve 26 are opened.

[0030] Reference Figure 2 As shown, the present invention also discloses a rapid cold start alkaline electrolysis hydrogen production method, which is applied to a rapid cold start alkaline electrolysis hydrogen production system as described in the above embodiment. The rapid cold start alkaline electrolysis hydrogen production method comprises the following steps:

[0031] S10, the hot water storage tank 1 exchanges heat with the alkali liquid in the alkali liquid storage tank 2 through the refrigerant in the first heat exchange pipe 6 and the second heat exchange pipe 5 to obtain alkali liquid with a temperature suitable for electrolysis; specifically, the specific method of exchanging heat between the refrigerant and the alkali liquid in the alkali liquid storage tank 2 is as follows: when the alkaline electrolytic cell is started, the liquid refrigerant absorbs heat in the hot water storage tank 1 and evaporates into a gaseous refrigerant, and the gaseous refrigerant is transported to the alkali liquid storage tank 2 through the first heat exchange pipe 6, and the compressor 7 further heats and pressurizes the gaseous refrigerant during the transportation process; the further heated and pressurized gaseous refrigerant releases heat in the alkali liquid storage tank 2 to heat the alkali liquid; after the heat release is completed, the gaseous refrigerant becomes liquid refrigerant, and the liquid refrigerant is depressurized through the throttle valve 8 and then transported back to the hot water storage tank 1 through the second heat exchange pipe 5;

[0032] S20, the alkali solution adapted for electrolysis enters the alkaline electrolysis cell 3 through the alkali solution delivery pipe 23 for electrolysis to obtain wet hydrogen and wet oxygen mixed with the alkali solution;

[0033] S30, the wet oxygen enters the oxygen separation mechanism to separate the alkali solution to obtain pure oxygen and output it through the oxygen output pipeline 16; the wet hydrogen enters the hydrogen separation mechanism to separate the alkali solution to obtain pure hydrogen and output it through the hydrogen output pipeline 22;

[0034] S40, the alkali liquid separated from the wet oxygen and wet hydrogen is heat-exchanged with the circulating water flowing from the hot water storage tank 1 in the waste heat recovery heat exchanger 4 and then recovered to the alkali liquid storage tank 2, and the circulating water after heat exchange flows back to the hot water storage tank 1.

[0035] It should be noted that, in this embodiment, the alkaline electrolysis hydrogen production system with rapid cold start can recover the heat generated by electrolysis to the hot water storage tank 1 through the above steps S10-S40, and can realize heat exchange between the hot water storage tank 1 and the alkali solution storage tank 2 through the first heat exchange pipe 6 and the second heat exchange pipe 5 to achieve heating of the alkali solution. In this process, the demand for external heating when the alkaline electrolysis hydrogen production system is started can be reduced, thereby shortening the cold start time, and heating the alkali solution by recycling the heat generated by electrolysis can improve energy utilization efficiency; in addition, by recovering heat to heat the alkali solution, damage to the equipment due to excessive heat or pressure can be avoided, so as to ensure the water and electricity safety of the equipment during the electrolysis process, thereby achieving the effect of shortening the cold start time, optimizing energy utilization efficiency, and ensuring the water and electricity safety of the equipment.

[0036] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A rapid cold start alkaline electrolysis hydrogen production system, characterized in that: The rapid cold start alkaline electrolysis hydrogen production system includes an alkali solution electrolysis unit, a waste heat recovery heat exchanger, an alkali solution storage tank, a hot water storage tank, a first heat exchange pipe, a second heat exchange pipe, a first waste heat recovery pipe, a second waste heat recovery pipe, a compressor and a throttle valve; the first waste heat recovery pipe and the second waste heat recovery pipe are connected between the alkali solution electrolysis unit and the waste heat recovery heat exchanger; the waste heat recovery heat exchanger is connected to the alkali solution storage tank and the hot water storage tank; the hot water storage tank is connected to the alkali solution electrolysis unit; the first heat exchange pipe and the second heat exchange pipe are both connected between the alkali solution storage tank and the hot water storage tank; the compressor is fixedly installed on the first heat exchange pipe; the throttle valve is fixedly installed on the second heat exchange pipe.

2. The alkaline electrolysis hydrogen production system with rapid cold start according to claim 1, characterized in that: The alkali liquid electrolysis unit includes an alkali liquid delivery pipeline, an alkali liquid circulation pump, an alkali liquid delivery valve, an alkaline electrolytic cell, an oxygen separation mechanism, and a hydrogen separation mechanism; the alkali liquid delivery pipeline is connected between the alkaline electrolytic cell and the alkali liquid storage tank; the alkali liquid circulation pump and the alkali liquid delivery valve are both fixedly installed on the alkali liquid delivery pipeline, and the alkali liquid delivery valve is close to the alkaline electrolytic cell, and the alkali liquid circulation pump is close to the alkali liquid storage tank; the oxygen separation mechanism and the hydrogen separation mechanism are both connected to the alkaline electrolytic cell.

3. The alkaline electrolysis hydrogen production system with rapid cold start according to claim 2, characterized in that: The oxygen separation mechanism includes a first separation liquid storage tank, a first gas-liquid separator, a first cooling water input pipe, a first cooling water output pipe, an oxygen output pipe and an oxygen outlet valve; the first separation liquid storage tank is connected between the alkaline electrolytic cell, the first waste heat recovery pipe and the first gas-liquid separator; the first gas-liquid separator is connected to the first cooling water input pipe, the first cooling water output pipe and the oxygen output pipe; the oxygen outlet valve is fixedly installed on the oxygen output pipe.

4. The alkaline electrolysis hydrogen production system with rapid cold start according to claim 2, characterized in that: The hydrogen separation mechanism includes a second separation liquid storage tank, a second gas-liquid separator, a second cooling water input pipeline, a second cooling water output pipeline, a hydrogen output pipeline, a hydrogen outlet valve and a water supply pipeline; the second separation liquid storage tank is connected between the alkaline electrolyzer, the second waste heat recovery pipeline and the second gas-liquid separator; the second gas-liquid separator is connected with the second cooling water input pipeline, the second cooling water output pipeline, the hydrogen output pipeline and the hydrogen output pipeline; the hydrogen outlet valve is fixedly installed on the hydrogen output pipeline.

5. The alkaline electrolysis hydrogen production system with rapid cold start according to claim 1, characterized in that: The rapid cold start alkaline electrolysis hydrogen production system also includes a third heat exchange pipe, a hot water storage tank circulation pump and a hot water storage tank heat exchange valve; the third heat exchange pipe is connected between the hot water storage tank and the waste heat recovery heat exchanger; the heat storage circulation pump and the hot water storage tank heat exchange valve are both fixedly installed on the third heat exchange pipe, and the heat storage circulation pump is located between the hot water storage tank and the heat storage vertical heat exchange valve.

6. The alkaline electrolysis hydrogen production system with rapid cold start according to claim 5, characterized in that: The rapid cold start alkaline electrolysis hydrogen production system also includes a third cooling water input pipeline, a cooling water inlet valve and a first cooling water three-way valve; the third cooling water input pipeline is connected to the third heat exchange pipeline; the cooling water inlet valve and the first cooling water three-way valve are both fixedly installed on the third cooling water input pipeline, and the first cooling water three-way valve is located at the connection point between the third cooling water input pipeline and the third heat exchange pipeline.

7. The alkaline electrolysis hydrogen production system with rapid cold start according to claim 1, characterized in that: The rapid cold start alkaline electrolysis hydrogen production system also includes a fourth heat exchange pipe, a third cooling water output pipe, a second cooling water three-way valve and a cooling water outlet valve; the fourth heat exchange pipe is connected between the waste heat recovery heat exchanger and the hot water storage tank; the cooling water output pipe is connected to the fourth heat exchange pipe; the second cooling water three-way valve is fixedly installed at the connection point between the cooling water output pipe and the fourth heat exchange pipe; the cooling water outlet valve is fixedly installed on the cooling water output pipe.

8. A rapid cold start alkaline electrolysis hydrogen production method, applied to a rapid cold start alkaline electrolysis hydrogen production system according to any one of claims 1 to 7, characterized in that: The rapid cold start alkaline electrolysis hydrogen production method comprises the following steps: The hot water storage tank exchanges heat with the alkali solution in the alkali solution storage tank through the refrigerant in the first heat exchange pipe and the second heat exchange pipe to obtain alkali solution with a temperature suitable for electrolysis; The alkali solution with temperature adapted for electrolysis enters the alkaline electrolysis cell through the alkali solution delivery pipeline for electrolysis to obtain wet hydrogen and wet oxygen mixed with the alkali solution; The wet oxygen enters the oxygen separation mechanism to separate the alkali solution to obtain pure oxygen and output it through the oxygen output pipeline; the wet hydrogen enters the hydrogen separation mechanism to separate the alkali solution to obtain pure hydrogen and output it through the hydrogen output pipeline; The alkali liquid separated from the wet oxygen and wet hydrogen is recovered to the alkali liquid storage tank after heat exchange with the circulating water flowing in from the hot water storage tank in the waste heat recovery heat exchanger, and the circulating water after heat exchange flows back to the hot water storage tank.

9. The method for producing hydrogen by alkaline electrolysis with rapid cold start according to claim 8, characterized in that: The specific method of exchanging heat between the refrigerant and the alkali liquid in the alkali liquid storage tank is as follows: when the alkaline electrolytic cell is started, the liquid refrigerant absorbs heat in the hot water storage tank and evaporates into gaseous refrigerant, and the gaseous refrigerant is transported to the alkali liquid storage tank through the first heat exchange pipeline, and the compressor further heats and pressurizes the gaseous refrigerant during the transportation process; the further heated and pressurized gaseous refrigerant releases heat in the alkali liquid storage tank to heat the alkali liquid; after the heat release is completed, the gaseous refrigerant becomes liquid refrigerant, and the liquid refrigerant is depressurized through the throttle valve and transported back to the hot water storage tank through the second heat exchange pipeline.

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