Alkaline electrolyzed water deoxygenation waste heat utilization system
By designing an alkaline water electrolysis deoxygenation waste heat utilization system during the hydrogen production process, the heat generated by the hydrogen-oxygen reaction is used to heat hydrogen and regenerated gas, thus solving the problem of heat energy waste and achieving energy consumption reduction and cost savings.
Patent Information
- Application Number
- CN202423239438.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-12-26
AI Technical Summary
In the existing process of hydrogen production by water electrolysis, thermal energy resources are wasted in a serious manner, resulting in high production costs. In addition, the hydrogen purification process requires electric heating, which increases energy consumption.
A waste heat utilization system for deoxygenation of alkaline water electrolysis is designed. The deoxygenated gas is used to heat crude hydrogen and regeneration gas through a primary heat exchanger and a secondary heat exchanger. The heat generated by the hydrogen-oxygen reaction is utilized to reduce the need for electric heating.
This approach enables the effective utilization of waste heat, reduces energy consumption, saves costs, and decreases the amount of desiccant used and the size of the equipment.
Smart Images
Figure CN223548113U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of hydrogen production technology through water electrolysis, specifically to a waste heat utilization system for deoxygenation in alkaline water electrolysis. Background Technology
[0002] Currently, hydrogen production mainly involves three methods: hydrogen production from fossil fuels, industrial by-product hydrogen, and hydrogen production through water electrolysis. In the water electrolysis process, the crude hydrogen produced after electrolysis is heated and enters a deoxygenation system. Impurities such as oxygen react with the hydrogen under the catalysis of a palladium catalyst to produce water, releasing a large amount of heat. This heat is typically removed using cooling water. Subsequently, the deoxygenated hydrogen needs to have the remaining moisture removed through adsorption to obtain dry hydrogen. However, in the hydrogen purification process, both the regeneration system and the adsorption-drying system require heating to maintain equipment temperature. Existing hydrogen purification processes generally use electric heating, which leads to a waste of thermal energy and relatively high production costs in water electrolysis.
[0003] In order to solve the above problems, people have been seeking an ideal technological solution. Utility Model Content
[0004] To address the shortcomings of existing technologies, this utility model provides an alkaline water electrolysis deoxygenation waste heat utilization system. By utilizing the heat generated during hydrogen production and deoxygenation from water electrolysis, the system aims to reduce energy consumption and save costs.
[0005] To achieve the above objectives, this utility model provides an alkaline water electrolysis deoxygenation waste heat utilization system, including an alkaline water electrolysis hydrogen production device and a palladium catalyst deoxygenation waste heat utilization device. The palladium catalyst deoxygenation waste heat utilization device includes a primary heat exchanger, a secondary heat exchanger, a deoxygenation system, a gas-liquid separation system, an adsorption drying system, and a regeneration system. The deoxygenation system includes a heater and a palladium catalyst deoxygenator. The gas-liquid separation system includes a low-temperature cooler and a gas-liquid separator. The regeneration system includes a regeneration gas cooler and a regeneration gas-liquid separator. The crude hydrogen inlet of the alkaline water electrolysis hydrogen production device is connected to the cold phase inlet of the primary heat exchanger, the cold phase outlet of the primary heat exchanger is connected to the inlet of the heater, the outlet of the heater is connected to the inlet of the palladium catalyst deoxygenator, and the outlet of the palladium catalyst deoxygenator is connected to the hot phase inlet of the primary heat exchanger. The hot phase outlet of the heat exchanger is connected to the hot phase inlet of the secondary heat exchanger; the hot phase outlet of the secondary heat exchanger is connected to the gas phase inlet of the cryogenic cooler, the gas phase outlet of the cryogenic cooler is connected to the gas phase inlet of the gas-liquid separator, the gas phase outlet of the gas-liquid separator is connected to the inlet of the adsorption drying system, the outlet of the adsorption drying system is used to output product hydrogen, the outlet of the adsorption drying system is also connected to the regeneration gas inlet of the secondary heat exchanger, the regeneration gas outlet of the secondary heat exchanger is connected to the regeneration gas inlet of the adsorption drying system; the regeneration gas outlet of the adsorption drying system is connected to the gas phase inlet of the regeneration gas cooler, the gas phase outlet of the regeneration gas cooler is connected to the inlet of the regeneration gas-liquid separator, and the outlet of the regeneration gas-liquid separator is also connected to the inlet of the adsorption drying system.
[0006] Furthermore, the heater is an electric heater, and the outlet of the electric heater is equipped with a first high-temperature alarm; the outlet of the palladium catalyst deaerator is equipped with a second high-temperature alarm, and the first high-temperature alarm and the second high-temperature alarm are respectively interlocked with the heater to control the heater to shut down.
[0007] Furthermore, the liquid phase cooling medium of the cryogenic cooler and the regenerated gas cooler is chilled water at 6℃~8℃. The gas phase outlets of the cryogenic cooler and the regenerated gas cooler are respectively equipped with a first temperature regulating valve device and a second temperature regulating valve device. The gas phase outlet temperatures of the cryogenic cooler and the regenerated gas cooler are both controlled between 15℃ and 25℃.
[0008] Furthermore, the gas-liquid separator and the regenerated gas-liquid separator are respectively equipped with a first high / low liquid level alarm and a second high / low liquid level alarm, and the bottom of the gas-liquid separator and the regenerated gas-liquid separator are respectively equipped with a first drain switch valve and a second drain switch valve; the first high / low liquid level alarm and the first drain switch valve and the second high / low liquid level alarm and the second drain switch valve are interlocked.
[0009] Furthermore, 15% to 20% of the product hydrogen output from the adsorption drying system is used as regenerated hydrogen and enters the secondary heat exchanger.
[0010] Furthermore, the adsorption drying system employs 2-3 adsorption towers, and the adsorption and regeneration of the adsorption towers are carried out according to a preset cycle. The adsorption towers are filled with molecular sieve desiccant.
[0011] Furthermore, the cold phase outlet of the secondary heat exchanger is equipped with a third temperature regulating valve device, and the temperature of the regeneration gas outlet of the secondary heat exchanger is controlled at 160℃~170℃.
[0012] Furthermore, the temperature of the crude hydrogen gas after preheating by the heater is 270°C; the temperature inside the palladium catalyst deaerator is controlled between 340°C and 360°C.
[0013] Compared with the prior art, the present invention has the following beneficial effects:
[0014] (1) The present invention provides an alkaline water electrolysis deoxygenation waste heat utilization system, comprising an alkaline water electrolysis hydrogen production device and a palladium catalyst deoxygenation waste heat utilization device. The palladium catalyst deoxygenation waste heat utilization device includes a primary heat exchanger, a secondary heat exchanger, a deoxygenation system, a gas-liquid separation system, an adsorption drying system, and a regeneration system. This waste heat utilization system, by adding a primary and secondary heat exchanger, uses the deoxygenated gas for heating crude hydrogen and regenerated gas. Compared with existing hydrogen purification processes, the improved waste heat utilization system of this invention can achieve complete heat generation from the hydrogen-oxygen reaction without the need for electric heating, thus saving energy.
[0015] (2) The alkaline electrolysis water deoxygenation waste heat utilization system of this utility model can effectively make comprehensive use of waste heat, reduce costs and save energy, reduce the amount of desiccant used, and reduce equipment size.
[0016] In addition to the objectives, features, and advantages described above, this utility model has other objectives, features, and advantages. The present utility model will now be described in further detail with reference to the accompanying drawings. Attached Figure Description
[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:
[0018] Figure 1 This is a schematic diagram of the structure of an alkaline water electrolysis deoxygenation waste heat utilization system according to this utility model;
[0019] Among them, 1-first-stage heat exchanger; 2-second-stage heat exchanger; 3-heater; 4-palladium catalyst deaerator; 5-low-temperature cooler; 6-gas-liquid separator; 7-adsorption drying system; 8-regenerated gas cooler; 9-regenerated gas-liquid separator; 10-alkaline electrolysis water hydrogen production unit. Detailed Implementation
[0020] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.
[0021] Please see Figure 1 This utility model provides an alkaline water electrolysis deoxygenation waste heat utilization system, including an alkaline water electrolysis hydrogen production device 10 and a palladium catalyst deoxygenation waste heat utilization device. The palladium catalyst deoxygenation waste heat utilization device includes a primary heat exchanger 1, a secondary heat exchanger 2, a deoxygenation system, a gas-liquid separation system, an adsorption drying system 7, and a regeneration system. The deoxygenation system includes a heater 3 and a palladium catalyst deoxygenator 4. The gas-liquid separation system includes a low-temperature cooler 5 and a gas-liquid separator 6. The regeneration system includes a regeneration gas cooler 8 and a regeneration gas-liquid separator 9. The specific structure is as follows:
[0022] The crude hydrogen inlet of the alkaline water electrolysis hydrogen production unit 10 is connected to the cold phase inlet of the primary heat exchanger 1. The cold phase outlet of the primary heat exchanger 1 is connected to the inlet of the heater 3. The outlet of the heater 3 is connected to the inlet of the palladium catalyst deoxygenator 4, and the outlet of the palladium catalyst deoxygenator 4 is connected to the hot phase inlet of the primary heat exchanger 1. The heater 3 is an electric heater, and its outlet is equipped with a first high-temperature alarm. The outlet of the palladium catalyst deoxygenator 4 is equipped with a second high-temperature alarm. The first and second high-temperature alarms are interlocked with the heater 3. When the first high-temperature alarm detects that the temperature at the outlet of the electric heater 3 exceeds the preset temperature, or when the second high-temperature alarm detects that the temperature at the outlet of the palladium catalyst deoxygenator 4 exceeds the preset temperature, a high-temperature alarm is issued, and the heater 3 is shut down.
[0023] The hot phase outlet of the primary heat exchanger 1 is connected to the hot phase inlet of the secondary heat exchanger 2; the hot phase outlet of the secondary heat exchanger 2 is connected to the gas phase inlet of the cryogenic cooler 5, the gas phase outlet of the cryogenic cooler 5 is connected to the gas phase inlet of the gas-liquid separator 6, and the gas phase outlet of the gas-liquid separator 6 is connected to the inlet of the adsorption drying system 7. The outlet of the adsorption drying system 7 produces qualified industrial hydrogen. The liquid phase cooling medium of the cryogenic cooler 5 is chilled water at 6℃~8℃. The gas phase outlet of the cryogenic cooler 5 has a first temperature regulating valve device, and the gas phase outlet temperature is controlled between 15℃~25℃. The gas-liquid separator 6 is equipped with a first high / low liquid level alarm, and a first drain valve is located at the bottom of the gas-liquid separator 6. The first high / low liquid level alarm and the first drain valve are interlocked. When the first high / low liquid level alarm sounds a high-level alarm, the first drain valve opens; when the first high / low liquid level alarm sounds a low-level alarm, the first drain valve closes. The adsorption drying system 7 employs 2-3 adsorption towers. Adsorption and regeneration of the adsorption towers are carried out according to a preset cycle, and the adsorption towers are filled with molecular sieve desiccant. Preferably, the liquid phase cooling medium of the low-temperature cooler 5 is 7°C chilled water, and the gas phase outlet temperature is controlled at 20°C.
[0024] The hydrogen pipeline from the outlet of the adsorption-drying system 7 is connected to the regeneration gas inlet of the secondary heat exchanger 2, and the regeneration gas outlet of the secondary heat exchanger 2 is connected to the regeneration gas inlet of the adsorption-drying system 7. The regeneration gas outlet of the adsorption-drying system 7 is connected to the gas phase inlet of the regeneration gas cooler 8, and the gas phase outlet of the regeneration gas cooler 8 is connected to the inlet of the regeneration gas-liquid separator 9. The outlet of the regeneration gas-liquid separator 9 is also connected to the inlet of the adsorption-drying system 7. In this configuration, 15%–20% of the hydrogen output from the adsorption-drying system 7 is used as regeneration hydrogen and enters the secondary heat exchanger 2 (i.e., the regeneration gas flow rate is controlled at 15–20%). After heat exchange with high-temperature crude aromatics, it passes through the adsorption-drying system 7 again before entering the regeneration gas cooler 8. The cold phase outlet of the secondary heat exchanger 2 is equipped with a third temperature regulating valve, which controls the temperature of the regeneration gas outlet of the secondary heat exchanger 2 to 160℃–170℃. The amount of cold medium in the secondary heat exchanger 2 is controlled by the third temperature regulating valve, thereby controlling the temperature of the regeneration gas. The liquid cooling medium in the regenerated gas cooler 8 is chilled water at 7°C. Both the liquid and gas phase outlets of the regenerated gas cooler 8 are equipped with a second temperature regulating valve, controlling the gas phase outlet temperature between 15°C and 25°C. The regenerated gas-liquid separator 9 is equipped with a second high / low liquid level alarm, and a second drain valve is located at its bottom. The second high / low liquid level alarm and the second drain valve are interlocked. Similarly, when the second high / low liquid level alarm issues a high-level alarm, the second drain valve opens; when the second high / low liquid level alarm issues a low-level alarm, the second drain valve closes.
[0025] In one specific embodiment, the crude hydrogen gas from the alkaline water electrolysis hydrogen production device is preheated by the heater 3 before entering the palladium catalyst deaerator 4, so that its temperature is greater than 270°C; the temperature of the palladium catalyst deaerator 4 is controlled at 350°C.
[0026] The specific steps for utilizing waste heat in the alkaline electrolysis water deoxygenation waste heat utilization system of this utility model are as follows:
[0027] The crude hydrogen gas (99.5-99.8% hydrogen, 0.2-0.5% oxygen, 40℃) generated from the alkaline water electrolysis hydrogen production unit first undergoes heat exchange in primary heat exchanger 1, then is heated by heater 3 before entering palladium catalyst deoxygenator 4. Impurities in the oxygen react with the hydrogen gas under the catalytic action of the palladium catalyst to produce water, releasing a large amount of heat. The high-temperature hydrogen gas after the reaction enters primary heat exchanger 1, where it exchanges heat with the crude hydrogen gas. Then, it undergoes secondary waste heat utilization with the regeneration gas in secondary heat exchanger 2, and then... Low-temperature crude hydrogen is obtained by cooling in low-temperature cooler 5 and removing some moisture in gas-liquid separator 6. Then, it passes through adsorption drying system 7 to obtain product hydrogen. Among them, 15% to 20% of the product hydrogen is used as regeneration gas for adsorption drying system 7. It exchanges heat with high-temperature hydrogen in secondary heat exchanger 2 to regenerate adsorption drying system 7. After the regeneration gas passes through regeneration gas cooler 8 and regeneration gas-liquid separator 9 to remove some moisture, it enters adsorption drying system 7 again with low-temperature crude hydrogen to obtain qualified hydrogen for downstream process.
[0028] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A waste heat recovery system for alkaline water electrolysis deoxygenation, characterized in that, The device includes an alkaline water electrolysis hydrogen production unit (10) and a palladium catalyst deoxygenation waste heat utilization unit. The palladium catalyst deoxygenation waste heat utilization unit includes a primary heat exchanger (1), a secondary heat exchanger (2), a deoxygenation system, a gas-liquid separation system, an adsorption drying system (7), and a regeneration system. The deoxygenation system includes a heater (3) and a palladium catalyst deoxygenator (4). The gas-liquid separation system includes a low-temperature cooler (5) and a gas-liquid separator (6). The regeneration system includes a regeneration gas cooler (8) and a regeneration gas separator (9). Liquid separator (9); the crude hydrogen inlet of the alkaline water electrolysis hydrogen production device (10) is connected to the cold phase inlet of the first-stage heat exchanger (1), the cold phase outlet of the first-stage heat exchanger (1) is connected to the inlet of the heater (3), the outlet of the heater (3) is connected to the inlet of the palladium catalyst deoxygenator (4), the outlet of the palladium catalyst deoxygenator (4) is connected to the hot phase inlet of the first-stage heat exchanger (1), and the hot phase outlet of the first-stage heat exchanger (1) is connected to the second-stage... The heat exchanger (2) is connected to the hot phase inlet; the hot phase outlet of the secondary heat exchanger (2) is connected to the gas phase inlet of the cryogenic cooler (5), the gas phase outlet of the cryogenic cooler (5) is connected to the gas phase inlet of the gas-liquid separator (6), the gas phase outlet of the gas-liquid separator (6) is connected to the inlet of the adsorption drying system (7), the outlet of the adsorption drying system (7) is used to output product hydrogen, the outlet of the adsorption drying system (7) is also connected to the regeneration gas inlet of the secondary heat exchanger (2), the regeneration gas outlet of the secondary heat exchanger (2) is connected to the regeneration gas inlet of the adsorption drying system (7); the regeneration gas outlet of the adsorption drying system (7) is connected to the gas phase inlet of the regeneration gas cooler (8), the gas phase outlet of the regeneration gas cooler (8) is connected to the inlet of the regeneration gas-liquid separator (9), and the outlet of the regeneration gas-liquid separator (9) is also connected to the inlet of the adsorption drying system (7).
2. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, The heater (3) is an electric heater, and the outlet of the electric heater (3) is equipped with a first high temperature alarm; the outlet of the palladium catalyst deaerator (4) is equipped with a second high temperature alarm. The first high temperature alarm and the second high temperature alarm are respectively interlocked with the heater (3) to control the heater (3) to shut down.
3. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, The liquid phase cooling medium of the low temperature cooler (5) and the regenerated gas cooler (8) is chilled water at 6℃~8℃. The gas phase outlets of the low temperature cooler (5) and the regenerated gas cooler (8) are respectively equipped with a first temperature regulating valve device and a second temperature regulating valve device. The gas phase outlet temperatures of the low temperature cooler (5) and the regenerated gas cooler (8) are both controlled at 15℃~25℃.
4. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, The gas-liquid separator (6) and the regenerated gas-liquid separator (9) are respectively equipped with a first high / low liquid level alarm and a second high / low liquid level alarm. The bottom of the gas-liquid separator (6) and the regenerated gas-liquid separator (9) are respectively equipped with a first drain valve and a second drain valve. The first high / low liquid level alarm is interlocked with the first drain valve and the second high / low liquid level alarm is interlocked with the second drain valve.
5. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, 15% to 20% of the product hydrogen output from the adsorption drying system (7) is used as regenerated hydrogen and enters the secondary heat exchanger (2).
6. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, The adsorption drying system (7) uses 2-3 adsorption towers. The adsorption and regeneration of the adsorption towers are carried out according to a preset cycle. The adsorption towers are filled with molecular sieve desiccant.
7. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, The cold phase outlet of the secondary heat exchanger (2) is equipped with a third temperature regulating valve device, and the temperature of the regeneration gas outlet of the secondary heat exchanger (2) is controlled at 160℃~170℃.
8. The alkaline electrolysis water deoxygenation waste heat utilization system according to claim 1, characterized in that, The temperature of the crude hydrogen gas after preheating by the heater (3) is 270°C; the temperature inside the palladium catalyst deaerator (4) is controlled between 340°C and 360°C.