Alkali liquor circulating system of alkaline water electrolytic bath capable of maintaining temperature after shutdown

Abstract

The utility model relates to an alkaline liquid circulating system of an alkaline water electrolytic bath capable of maintaining temperature after shutdown, which comprises an electrolytic bath and a temperature maintaining heating system, the temperature maintaining heating system comprises an external heating device, and the external heating device is arranged on the outer surface of the electrolytic bath; the electrolytic bath is connected with an alkali liquor cooler through an alkali liquor circulating pump, and the alkali liquor cooler is provided with a circulating cooling water supply pipeline and a circulating cooling water return pipeline; the electrolytic cell is respectively connected with a hydrogen separator and an oxygen separator, and liquid outlets of the oxygen separator and the hydrogen separator are connected to an alkali liquor cooler; a gas outlet of the hydrogen separator is connected with the hydrogen scrubber, a gas outlet of the oxygen separator is connected with the oxygen scrubber, liquid inlets of the hydrogen scrubber and the oxygen scrubber are connected with raw material water, the hydrogen scrubber is connected with the hydrogen cooling separator, and the oxygen scrubber is connected with the oxygen cooling separator. The electrolytic bath can operate safely and stably for a long time, and the service life of the electrolytic bath is greatly prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of hydrogen production by electrolysis of water, in particular to an alkaline solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance. Background Art

[0002] Alkaline water electrolysis is the only technology that can achieve large-scale, long-term renewable energy power storage. Alkaline water electrolysis is a mature technical means. However, the current alkaline water electrolysis hydrogen production equipment, especially the use scenarios of green electricity hydrogen production such as photovoltaic and wind power generation, due to the characteristics of green electricity load fluctuations, the electrolyzer is in a large range of load fluctuations, and the frequent start-stop during the day and shut down at night are unstable. The frequent start-stop causes the temperature of the electrolyzer itself to change greatly, making the electrolyzer easily damaged by the influence of thermal expansion and contraction, causing the outflow of alkali solution and the scrapping of the electrolyzer, which seriously affects the safety and service life of the electrolyzer.

[0003] Therefore, in view of the above existing problems, there is an urgent need for an alkali solution circulation system for an alkaline water electrolyzer that can be shut down to maintain temperature. Utility Model Content

[0004] The utility model aims to overcome the above-mentioned shortcomings and provide an alkali solution circulation system for an alkaline water electrolytic cell which can be shut down to maintain temperature, thereby eliminating thermal expansion and contraction caused by frequent start and stop of the electrolytic cell, thereby avoiding the electrolytic cell being scrapped due to gasket damage and reducing maintenance costs.

[0005] The purpose of the utility model is achieved in this way:

[0006] A lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance, comprising an electrolyzer and a temperature maintenance heating system, wherein the temperature maintenance heating system comprises an external heating device, and the external heating device is arranged on the outer surface of the electrolyzer; the electrolyzer is connected to a lye cooler via a lye circulation pump, and the lye cooler is provided with a circulating cooling water supply pipeline and a circulating cooling water return pipeline; the electrolyzer is respectively connected to a hydrogen separator and an oxygen separator, and the liquid outlets of the oxygen separator and the hydrogen separator are both connected to the lye cooler;

[0007] The gas outlet of the hydrogen separator is connected to the hydrogen scrubber, the gas outlet of the oxygen separator is connected to the oxygen scrubber, the liquid inlets of the hydrogen scrubber and the oxygen scrubber are connected to raw water, the hydrogen scrubber is connected to the hydrogen cooling separator, and the oxygen scrubber is connected to the oxygen cooling separator;

[0008] One side of the hydrogen cooling separator and the oxygen cooling separator are respectively connected to a chilled water supply pipeline, and the other side of the hydrogen cooling separator and the oxygen cooling separator are respectively connected to a chilled water return pipeline.

[0009] Furthermore, the external heating device is an electric tracing heating device.

[0010] Furthermore, the external heating device adopts a hot water coil heating device.

[0011] Furthermore, a hot water supply pipeline is added to the circulating cooling water supply pipeline of the alkali liquid cooler, and a hot water return pipeline is added to the circulating cooling water return pipeline of the alkali liquid cooler; valves are set at the inlet and outlet of the hot water supply pipeline and the hot water return pipeline.

[0012] Furthermore, the temperature maintenance heating system leads out two branch pipes on the circulating cooling water system of the alkali liquid cooler: namely, the circulating cooling water supply branch and the circulating cooling water return branch of the alkali liquid cooler. The circulating cooling water supply branch and the circulating cooling water return branch are connected to the waste heat utilization system, and the waste heat utilization system is connected to the energy storage tank through a high-temperature hot water supply pipeline.

[0013] Furthermore, the energy storage tank is connected to the waste heat utilization system through a high-temperature hot water return pipeline, the energy storage tank is connected to the circulating cooling water supply branch through a second high-temperature hot water supply pipeline, and the energy storage tank is connected to the circulating cooling water return branch through a second high-temperature hot water return pipeline.

[0014] Furthermore, a heat preservation device is arranged on the surface of the electrolytic cell and the alkali liquid cooler.

[0015] Furthermore, the body temperature of the electrolytic cell is controlled according to the body temperature under operating conditions when the electrolytic cell is shut down, and the lower temperature of the electrolytic cell is lower than the upper temperature.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] The utility model provides an alkali liquid circulation system of an alkaline water electrolytic cell that can be shut down for temperature maintenance, and a shutdown temperature maintenance heating system for the electrolytic cell. In a non-operating state, the temperature maintenance heating system is used to ensure that the electrolytic cell is consistent with the operating state of the electrolytic cell when it is shut down, and the cell body temperature is constant within the range of 90±10°C. The cell body temperature remains basically constant, eliminating the problem of thermal expansion and contraction caused by frequent shutdown of the electrolytic cell. The utility model controls heating and heat preservation during shutdown, so that the gaskets of the electrolytic cell and the system are not affected by thermal expansion and contraction, the shape of the gaskets can remain unchanged, and the electrolytic cell will be stable in the same geometric size for a long time; the electrolytic cell can be operated safely and stably for a long time, greatly improving the service life of the electrolytic cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of Example 1 of the utility model.

[0019] Figure 2 This is a schematic structural diagram of Example 2 of the present utility model.

[0020] Figure 3 This is a schematic structural diagram of Example 3 of the present utility model.

[0021] Figure 4 This is a schematic structural diagram of Example 4 of the present utility model.

[0022] in:

[0023] Electrolyzer 1, alkali liquid cooler 2, alkali liquid circulation pump 3, hydrogen separator 4, hydrogen scrubber 5, oxygen separator 6, oxygen scrubber 7, hydrogen cooling separator 8, oxygen cooling separator 9, electric heating device 10, hot water coil heating device 11, hot water supply pipeline 12, hot water return pipeline 13, waste heat utilization system 14, energy storage tank 15, high-temperature hot water supply pipeline 16, high-temperature hot water return pipeline 17. DETAILED DESCRIPTION

[0024] In order to better understand the technical solution of the present invention, the following will be described in detail in conjunction with the relevant illustrations. It should be understood that the following specific embodiments are not intended to limit the specific implementation of the technical solution of the present invention, and are only implementations that can be adopted by the technical solution of the present invention. It should be noted that the description of the positional relationship of each component in this article, such as component A being located above component B, is based on the description of the relative positions of the components in the illustration, and is not intended to limit the actual positional relationship of the components. Embodiment 1:

[0025] See also Figure 1 , Figure 1 A lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance in Example 1 is drawn. As shown in the figure, a lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance in Example 1 comprises an electrolytic cell 1 and a temperature maintenance heating system, wherein the temperature maintenance heating system comprises an electric tracing heating device 10, and the outer surface of the electrolytic cell 1 is provided with the electric tracing heating device 10.

[0026] The electric heating device 10 includes an electric heating tape wound around the outer surface of the electrolytic cell 1. The electric heating tape can be cut into any length as needed and connected through a two-way or three-way junction box; the junction box is responsible for introducing power into the electric heating tape and ensuring the safety of the power supply. The junction box is equipped with a power switch inside to control the power supply of the entire electric heating tape system and is equipped with an explosion-proof plate to effectively prevent safety hazards caused by overheating of the electric heating tape.

[0027] The electric heating tape is also connected to a thermostat, which automatically adjusts the electric heating tape according to the set temperature. When the temperature is lower than the set value, the thermostat will automatically turn on the electric heating tape for heating; when the temperature is higher than the set value, the thermostat will disconnect the circuit and stop heating. The electric heating tape is also connected to a distribution box, which serves as the power control center of the electric heating tape system. It controls the on and off of the power and adjusts the output power of the electric heating tape. The distribution box can also monitor the power status of the electric heating tape system in real time and is equipped with an alarm device. When the electric heating tape is in abnormal conditions such as overload or short circuit, an alarm will sound to remind the user.

[0028] The electrolytic cell 1 is connected to the alkali liquid cooler 2 via an alkali liquid circulation pump 3, and the alkali liquid cooler 2 is provided with a circulating cooling water supply pipeline and a circulating cooling water return pipeline; the electrolytic cell 1 is respectively connected to the hydrogen separator 4 and the oxygen separator 6, and the liquid outlets of the oxygen separator 6 and the hydrogen separator 4 are both connected to the alkali liquid cooler 2;

[0029] The gas outlet of the hydrogen separator 4 is connected to the hydrogen scrubber 5, the gas outlet of the oxygen separator 6 is connected to the oxygen scrubber 7, the liquid inlets of the hydrogen scrubber 5 and the oxygen scrubber 7 are connected to raw water, the hydrogen scrubber 5 is connected to the hydrogen cooling separator 8, and the oxygen scrubber 7 is connected to the oxygen cooling separator 9.

[0030] One side of the hydrogen cooling separator 8 and the oxygen cooling separator 9 is connected to a chilled water supply pipeline, and the other side of the hydrogen cooling separator 8 and the oxygen cooling separator 9 is connected to a chilled water return pipeline.

[0031] The temperature maintenance heating system is enabled when the electrolytic cell is shut down and is turned off when the electrolytic cell is running. The temperature maintenance heating system keeps the temperature of the electrolytic cell basically consistent when it is shut down and when it is running. In the non-operating state, the temperature maintenance heating system is used to ensure that the electrolytic cell is consistent with the operating state when it is shut down, and the cell body temperature is constant within the range of 90±10℃. The cell body temperature remains basically constant, eliminating the problem of thermal expansion and contraction caused by frequent start and stop of the electrolytic cell. Embodiment 2:

[0032] See also Figure 2 , Figure 2 A lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance in Example 2 is drawn. As shown in the figure, the lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance in Example 2 is different from that in Example 1 in that the temperature maintenance heating system includes a hot water coil heating device 11 and a constant temperature control system, and a hot water coil heating device 11 is arranged on the outer surface of the electrolyzer 1.

[0033] The hot water coil heating device 11 includes a plurality of heating tubes arranged in parallel and a shell outside the heating tubes, one end of each heating tube is a water inlet and the other end is a hot water outlet; the outer wall of the heating tube is coated with fire retardant paint, and the outside of the paint is a high temperature resistant insulating layer. Embodiment 3:

[0034] See also Figure 3 , Figure 3 A lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance in Example 3 is drawn. As shown in the figure, the lye circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance in Example 3 is different from that in Example 1 in that a hot water supply pipeline 12 is added to the circulating cooling water supply pipeline of the lye cooler 2, and a hot water return pipeline 13 is added to the circulating cooling water return pipeline of the lye cooler 2.

[0035] Valves are arranged at the inlet and outlet of the hot water supply pipe 12 and the hot water return pipe 13. When the electrolytic cell is shut down, the circulating cooling water inlet and outlet valves are closed, and the hot water inlet and outlet valves are opened. The alkali solution circulation system operates normally, and hot water is introduced to heat the alkali solution in the alkali solution cooler. Through the constant temperature control system, the alkali solution temperature when the electrolytic cell is shut down is basically consistent with the temperature when the electrolytic cell is running. Embodiment 4:

[0036] See also Figure 4 , Figure 4 A lye circulation system of an alkaline water electrolyzer that can be shut down for temperature maintenance in Example 4 is drawn. As shown in the figure, the lye circulation system of an alkaline water electrolyzer that can be shut down for temperature maintenance in Example 4 is different from that in Example 1 in that the temperature maintenance heating system leads out two branch pipes on the circulating cooling water system of the lye cooler 2: the circulating cooling water supply branch and the circulating cooling water return branch of the lye cooler 2, the circulating cooling water supply branch and the circulating cooling water return branch are connected to the waste heat utilization system 14, the waste heat utilization system 14 is connected to the energy storage tank 15 through the high-temperature hot water supply pipeline 16, the energy storage tank 15 is circulated and connected to the waste heat utilization system 14 through the high-temperature hot water return pipeline 17, the energy storage tank 15 is connected to the circulating cooling water supply branch through the second high-temperature hot water supply pipeline, and the energy storage tank 15 is connected to the circulating cooling water return branch through the second high-temperature hot water return pipeline.

[0037] When the electrolytic cell is running, part of the waste heat of the alkali liquid cooler is used, and this part of the waste heat is recovered through an absorption heat pump or an electric heat pump to produce high-temperature hot water, which is stored in an energy storage tank. When the electrolytic cell is shut down, the high-temperature hot water in the energy storage tank is passed into the alkali liquid cooler to heat the alkali liquid. The alkali liquid circulation system runs normally. Through the constant temperature control system, the alkali liquid temperature when the electrolytic cell is shut down is basically consistent with the temperature when the electrolytic cell is running. At the same time, the waste heat is used to achieve the purpose of energy and water saving.

[0038] In this embodiment, in order to reduce the load of the shutdown temperature maintenance heating system, the electrolytic cell, the alkali solution system, the hydrogen and oxygen liquid separator, etc. can be subjected to insulation treatment.

[0039] The temperature of the cell body of the electrolytic cell is controlled according to the cell body temperature under the operating condition when the electrolytic cell is shut down, with the temperature of the lower part of the electrolytic cell being low and the temperature of the upper part being high.

[0040] The above are only specific application examples of the utility model, and do not constitute any limitation on the protection scope of the utility model. Any technical solution formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the utility model.

Claims

1. An alkali solution circulation system for an alkaline water electrolyzer capable of shutting down to maintain temperature, characterized in that: It comprises an electrolytic cell (1) and a temperature-maintaining heating system, wherein the temperature-maintaining heating system comprises an external heating device, and the external heating device is arranged on the outer surface of the electrolytic cell (1); the electrolytic cell (1) is connected to an alkali liquid cooler (2) via an alkali liquid circulation pump (3), and the alkali liquid cooler (2) is provided with a circulating cooling water supply pipeline and a circulating cooling water return pipeline; the electrolytic cell (1) is respectively connected to a hydrogen separator (4) and an oxygen separator (6), and the liquid outlets of the oxygen separator (6) and the hydrogen separator (4) are both connected to the alkali liquid cooler (2); The gas outlet of the hydrogen separator (4) is connected to the hydrogen scrubber (5), the gas outlet of the oxygen separator (6) is connected to the oxygen scrubber (7), the liquid inlets of the hydrogen scrubber (5) and the oxygen scrubber (7) are connected to raw water, the hydrogen scrubber (5) is connected to the hydrogen cooling separator (8), and the oxygen scrubber (7) is connected to the oxygen cooling separator (9); One side of the hydrogen cooling separator (8) and the oxygen cooling separator (9) are respectively connected to a chilled water supply pipeline, and the other side of the hydrogen cooling separator (8) and the oxygen cooling separator (9) are respectively connected to a chilled water return pipeline.

2. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 1, characterized in that: The external heating device is an electric tracing heating device (10).

3. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 1, characterized in that: The external heating device adopts a hot water coil heating device (11).

4. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 1, characterized in that: A hot water supply pipeline (12) is added to the circulating cooling water supply pipeline of the alkali liquid cooler (2), and a hot water return pipeline (13) is added to the circulating cooling water return pipeline of the alkali liquid cooler (2); valves are provided at the inlets and outlets of the hot water supply pipeline (12) and the hot water return pipeline (13).

5. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 1, characterized in that: The temperature maintenance heating system leads out two branch pipelines on the circulating cooling water system of the alkali liquid cooler (2): a circulating cooling water supply branch and a circulating cooling water return branch of the alkali liquid cooler (2), the circulating cooling water supply branch and the circulating cooling water return branch are connected to the waste heat utilization system (14), and the waste heat utilization system (14) is connected to the energy storage tank (15) via a high-temperature hot water supply pipeline (16).

6. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 5, characterized in that: The energy storage tank (15) is cyclically connected to the waste heat utilization system (14) via a high-temperature hot water return pipeline (17); the energy storage tank (15) is connected to a circulating cooling water supply branch via a second high-temperature hot water supply pipeline; and the energy storage tank (15) is connected to a circulating cooling water return branch via a second high-temperature hot water return pipeline.

7. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 1, characterized in that: Heat preservation devices are arranged on the surfaces of the electrolytic cell (1) and the alkali liquid cooler (2).

8. The alkali solution circulation system of an alkaline water electrolyzer capable of shutting down for temperature maintenance according to claim 1, characterized in that: The body temperature of the electrolytic cell (1) is controlled according to the body temperature under operating conditions when the electrolytic cell (1) is shut down, and the temperature of the lower part of the electrolytic cell (1) is lower than the temperature of the upper part.

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