Energy-saving alkaline water electrolysis gas-liquid separation system

Abstract

The utility model discloses an energy-saving alkaline water gas-liquid separation system, which is characterized in that hydrogen discharged from an electrolytic bath firstly exchanges heat with hydrogen discharged from a scrubber, the hydrogen enters a gas-liquid separator after the temperature is reduced, and the hydrogen after gas-liquid separation enters the scrubber after being cooled by a cooler; the low-temperature hydrogen from the scrubber exchanges heat with the high-temperature hydrogen at the outlet of the electrolytic cell, after the temperature is increased, the low-temperature hydrogen enters the purification device at the rear end, the gas-liquid separation effect is improved, the hydrogen subjected to gas-liquid separation enters the scrubber after being cooled by the cooler, the washing effect is improved, and the reaction temperature of the deoxidation reactor at the rear end is 80 DEG C; and the hydrogen enters the purification device at the rear end after being heated, so that heat energy utilization can be increased.

Description

Technical Field

[0001] The utility model relates to the field of hydrogen production equipment, in particular to an energy-saving alkaline water electrolysis gas-liquid separation system. Background Art

[0002] After electrolysis, the electrolysis system will produce a large amount of gas-liquid mixture, which needs to be processed by the gas-liquid separation system to separate dry and pure hydrogen and oxygen. The gas-liquid separation device is equipped with hydrogen separation scrubber, oxygen separator, hydrogen cooler, gas-water separator, alkali liquid circulation pump and other equipment.

[0003] Generally, hydrogen-oxygen separators and gas coolers are set up independently. The electrolyte containing hydrogen and oxygen passes through the hydrogen and oxygen separators respectively, and is separated from the electrolytic alkali solution by gravity. The separated hydrogen enters the separation device for washing, cooling, separation and removal of droplets, and then enters the hydrogen purification device. Only its basic functions are considered, and the lost heat is not comprehensively utilized, and the separation effect is not ideal. In addition, the washed hydrogen is in a low-temperature state. The existing process still requires an external heating system to heat it to 80°C to reach the reaction temperature of the deoxygenation reactor when entering the back-end purification device, which increases energy consumption.

[0004] In summary, an energy-saving alkaline water electrolysis gas-liquid separation system is needed to solve the deficiencies in the prior art. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model provides an energy-saving alkaline water electrolysis gas-liquid separation system, aiming to solve the above problems.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an energy-saving alkaline water electrolysis gas-liquid separation system, comprising an electrolytic cell, an alkali solution reflux unit, a pure water circulation unit and a cooling water circulation unit, an oxygen purification unit and a hydrogen purification unit are arranged on the electrolytic cell, the oxygen purification unit and the hydrogen purification unit are both connected to the upper part of the electrolytic cell, the cooling water circulation unit is both connected to the oxygen purification unit and the hydrogen purification unit, and the oxygen purification unit and the hydrogen purification unit are both connected to the lower part of the electrolytic cell through the alkali solution reflux unit.

[0007] The electrolyzer electrolyzes alkaline water to produce oxygen and hydrogen. The oxygen enters the oxygen purification unit and enters the oxygen collection device after purification. At the same time, the hydrogen enters the hydrogen purification unit and enters the hydrogen collection device after purification. The pure water circulation unit enters the oxygen purification unit and the hydrogen purification unit respectively to clean the oxygen and hydrogen produced by electrolysis. The alkali liquid reflux unit returns the alkali liquid produced during the cleaning of the oxygen purification unit and the hydrogen purification unit to the electrolyzer. The cooling water circulation unit performs heat exchange with the oxygen purification unit and the hydrogen purification unit to cool the oxygen and hydrogen.

[0008] Optionally, the hydrogen purification unit includes a hydrogen precooler, a hydrogen separator, a hydrogen cooler and a hydrogen scrubber. The hydrogen outlet pipe at the upper part of the electrolyzer passes through the hydrogen precooler and is connected to the hydrogen separator. The lower part of the hydrogen separator is connected to the lower part of the electrolyzer through an alkali liquid reflux unit. The hydrogen cooler is connected to the hydrogen separator. The upper part of the hydrogen scrubber is connected to the hydrogen cooler, the cooling water circulation unit is connected to the hydrogen cooler, the pure water circulation unit is connected to the hydrogen scrubber, and the lower part of the hydrogen scrubber is connected to the hydrogen separator through the pure water circulation unit.

[0009] The hydrogen produced by the electrolyzer first enters the hydrogen precooler for heat exchange with the purified hydrogen. The hydrogen after heat exchange enters the hydrogen separator to separate the hydrogen from other products such as alkali solution, and is cleaned and purified for the first time under the action of the pure water system. Then it enters the hydrogen cooler for heat exchange with the cooling water circulation unit. The hydrogen after heat exchange enters the hydrogen scrubber, where it is cleaned and purified for the second time through the pure water system. The purified hydrogen enters the hydrogen precooler for heat exchange with the hydrogen produced by the electrolyzer, and finally enters the purification system.

[0010] Optionally, a hydrogen product outlet temperature transmitter is provided between the hydrogen separator and the electrolyzer.

[0011] The hydrogen product outlet temperature transmitter is used to detect the temperature of the hydrogen produced by the electrolyzer.

[0012] Optionally, a hydrogen thermometer is provided on the hydrogen scrubber, and the hydrogen thermometer is fixedly connected to the hydrogen scrubber. The hydrogen thermometer is used to measure the temperature inside the hydrogen scrubber.

[0013] Optionally, the outlet pipe of the hydrogen scrubber passes through a hydrogen precooler, and a hydrogen precooler air inlet valve and a hydrogen precooler bypass valve are fixedly arranged on the outlet pipe of the hydrogen scrubber.

[0014] Optionally, the oxygen purification unit includes an oxygen separator, an oxygen cooler and an oxygen scrubber, the oxygen separator is connected to the upper part of the electrolyzer, the lower part of the oxygen separator is connected to the lower part of the electrolyzer through an alkali liquid reflux unit, the oxygen cooler is connected to the oxygen separator, the upper part of the oxygen scrubber is connected to the oxygen cooler, the cooling water circulation unit is connected to the oxygen cooler, the pure water circulation unit is connected to the oxygen scrubber, and the lower part of the oxygen scrubber is connected to the oxygen separator through the pure water circulation unit.

[0015] The oxygen produced by the electrolytic cell enters the oxygen separator, where it is separated from other products such as alkali solution, and is cleaned and purified for the first time through a pure water system. The separated oxygen enters the oxygen cooler, where it undergoes heat exchange with a cooling water circulation unit. The oxygen after the heat exchange enters the oxygen scrubber, where it undergoes a second cleaning and purification through a pure water system.

[0016] Optionally, an oxygen product outlet temperature transmitter is provided between the oxygen separator and the electrolyzer.

[0017] The oxygen product outlet temperature transmitter is used to detect the temperature of oxygen produced by the electrolyzer.

[0018] Optionally, an oxygen thermometer is provided on the oxygen scrubber, and the oxygen thermometer is fixedly connected to the oxygen scrubber. The oxygen thermometer is used to measure the temperature inside the oxygen scrubber.

[0019] Optionally, an oxygen scrubber exhaust valve is fixedly arranged on the outlet pipe of the oxygen scrubber, an oxygen scrubber bypass valve is arranged on one side of the oxygen scrubber exhaust valve, and two ends of the oxygen scrubber bypass valve are respectively fixedly connected to two ends of the oxygen scrubber exhaust valve.

[0020] Beneficial effects of the utility model:

[0021] 1. In the utility model, the hydrogen coming out of the electrolyzer is first heat exchanged with the hydrogen coming out of the scrubber, and then enters the gas-liquid separator after the temperature is reduced. The hydrogen after gas-liquid separation is cooled by the cooler and then enters the scrubber. The low-temperature hydrogen coming out of the scrubber is heat exchanged with the high-temperature hydrogen at the outlet of the electrolyzer, and then enters the rear-end purification device after the temperature is increased.

[0022] 2. In the utility model, the gas-liquid separation effect is increased, and the hydrogen after gas-liquid separation is cooled by the cooler and then enters the scrubber, thereby increasing the scrubbing effect;

[0023] 3. In the present invention, the reaction temperature of the rear-end deoxygenation reactor is 80°C, and the hydrogen gas enters the rear-end purification device after the temperature is raised, which can increase the utilization of thermal energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The utility model is a schematic diagram of a system structure.

[0025] In the figure: 1. electrolyzer; 2. hydrogen purification unit; 3. oxygen purification unit; 4. cooling water circulation unit; 5. pure water circulation unit; 6. alkali solution reflux unit; 21. hydrogen precooler; 22. hydrogen separator; 23. hydrogen scrubber; 24. hydrogen cooler; 25. hydrogen product outlet temperature transmitter; 26. hydrogen thermometer; 27. hydrogen precooler inlet valve; 28. hydrogen precooler bypass valve; 31. oxygen separator; 32. oxygen cooler; 33. oxygen scrubber; 34. oxygen product outlet temperature transmitter; 35. oxygen thermometer; 36. oxygen scrubber exhaust valve; 37. oxygen scrubber bypass valve. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] like Figure 1 As shown, an energy-saving alkaline water electrolysis gas-liquid separation system includes an electrolytic cell 1, an alkali solution reflux unit 6, a pure water circulation unit 5 and a cooling water circulation unit 4. An oxygen purification unit 3 and a hydrogen purification unit 2 are arranged on the electrolytic cell 1. The oxygen purification unit 3 and the hydrogen purification unit 2 are both connected to the upper part of the electrolytic cell 1, the cooling water circulation unit 5 is connected to the oxygen purification unit 3 and the hydrogen purification unit 2, the cooling water circulation unit 4 is connected to the oxygen purification unit 3 and the hydrogen purification unit 2, and the oxygen purification unit 3 and the hydrogen purification unit 2 are both connected to the lower part of the electrolytic cell 1 through the alkali solution reflux unit 6.

[0028] The hydrogen purification unit 2 includes a hydrogen precooler 21, a hydrogen separator 22, a hydrogen cooler 23 and a hydrogen scrubber 24. The hydrogen outlet pipe at the upper part of the electrolyzer 1 passes through the hydrogen precooler 21 and is connected to the hydrogen separator 22. The lower part of the hydrogen separator 22 is connected to the lower part of the electrolyzer 1 through the alkali liquid reflux unit 6. The hydrogen cooler 24 is connected to the hydrogen separator 22. The upper part of the hydrogen scrubber 23 is connected to the hydrogen cooler 24. The cooling water circulation unit 4 is connected to the hydrogen cooler 24. The pure water circulation unit 5 is connected to the hydrogen scrubber 23. The lower part of the hydrogen scrubber 23 is connected to the hydrogen separator 22 through the pure water circulation unit 5.

[0029] A hydrogen product outlet temperature transmitter 25 is arranged between the hydrogen separator 22 and the electrolyzer 1, a hydrogen thermometer 26 is arranged on the hydrogen scrubber 23, the hydrogen thermometer 26 is fixedly connected to the hydrogen scrubber 23, the outlet pipe of the hydrogen scrubber 23 passes through the hydrogen precooler 21, and a hydrogen precooler inlet valve 27 and a hydrogen precooler bypass valve 28 are fixedly arranged on the outlet pipe of the hydrogen scrubber 23.

[0030] The oxygen purification unit 3 includes an oxygen separator 31, an oxygen cooler 32 and an oxygen scrubber 33. The oxygen separator 31 is connected to the upper part of the electrolytic cell 1, and the lower part of the oxygen separator 31 is connected to the lower part of the electrolytic cell 1 through the alkali solution reflux unit 6. The oxygen cooler 32 is connected to the oxygen separator 31. The upper part of the oxygen scrubber 33 is connected to the oxygen cooler 32. The cooling water circulation unit 4 is connected to the oxygen cooler 32. The pure water circulation unit 5 is connected to the oxygen scrubber 33. The lower part of the oxygen scrubber 33 is connected to the oxygen separator 31 through the pure water circulation unit 5.

[0031] An oxygen product outlet temperature transmitter 34 is arranged between the oxygen separator 31 and the electrolytic cell 1, an oxygen thermometer 35 is arranged on the oxygen scrubber 33, and the oxygen thermometer 35 is fixedly connected to the oxygen scrubber 33. An oxygen scrubber exhaust valve 36 is fixedly arranged on the outlet pipe of the oxygen scrubber 33, and an oxygen scrubber bypass valve 37 is arranged on one side of the oxygen scrubber exhaust valve 36, and both ends of the oxygen scrubber bypass valve 37 are fixedly connected to both ends of the oxygen scrubber exhaust valve 36 respectively.

[0032] The working principle of the utility model is as follows: the hydrogen generated by the electrolyzer first enters the hydrogen precooler to perform heat exchange with the purified hydrogen, the hydrogen after the heat exchange enters the hydrogen separator to separate the hydrogen from other products such as alkali solution, and performs the first cleaning and purification under the action of the pure water system, and then enters the hydrogen cooler to perform heat exchange with the cooling water circulation unit, the hydrogen after the heat exchange enters the hydrogen scrubber, and performs the second cleaning and purification of the hydrogen through the pure water system in the hydrogen scrubber, the purified hydrogen enters the hydrogen precooler to perform heat exchange with the hydrogen generated by the electrolyzer, and finally enters the purification system.

[0033] The hydrogen product outlet temperature transmitter is used to detect the temperature of the hydrogen produced by the electrolyzer, and the hydrogen thermometer is used to measure the temperature inside the hydrogen scrubber.

[0034] The oxygen produced by the electrolytic cell enters the oxygen separator, where it is separated from other products such as alkali solution, and is cleaned and purified for the first time through a pure water system. The separated oxygen enters the oxygen cooler, where it undergoes heat exchange with a cooling water circulation unit. The oxygen after the heat exchange enters the oxygen scrubber, where it undergoes a second cleaning and purification through a pure water system.

[0035] The oxygen product outlet temperature transmitter is used to detect the temperature of the oxygen produced by the electrolyzer, and the oxygen thermometer is used to measure the temperature inside the oxygen scrubber.

[0036] To increase the gas-liquid separation effect, the hydrogen after gas-liquid separation is cooled by the cooler and then enters the scrubber to increase the scrubbing effect. The reaction temperature of the rear-end deoxygenation reactor is 80°C. After the hydrogen temperature is raised, it enters the rear-end purification device to increase the utilization of thermal energy.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An energy-saving alkaline water electrolysis gas-liquid separation system, characterized in that: It includes an electrolytic cell, an alkali solution reflux unit, a pure water circulation unit and a cooling water circulation unit. An oxygen purification unit and a hydrogen purification unit are arranged on the electrolytic cell. Both the oxygen purification unit and the hydrogen purification unit are connected to the upper part of the electrolytic cell. Both the cooling water circulation unit are connected to the oxygen purification unit and the hydrogen purification unit. Both the oxygen purification unit and the hydrogen purification unit are connected to the lower part of the electrolytic cell through the alkali solution reflux unit.

2. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 1, characterized in that: The hydrogen purification unit comprises a hydrogen precooler, a hydrogen separator, a hydrogen cooler and a hydrogen scrubber. The hydrogen outlet pipe at the upper part of the electrolyzer passes through the hydrogen precooler and is connected to the hydrogen separator. The lower part of the hydrogen separator is connected to the lower part of the electrolyzer through an alkali liquid reflux unit. The hydrogen cooler is connected to the hydrogen separator. The upper part of the hydrogen scrubber is connected to the hydrogen cooler. The cooling water circulation unit is connected to the hydrogen cooler. The pure water circulation unit is connected to the hydrogen scrubber. The lower part of the hydrogen scrubber is connected to the hydrogen separator through the pure water circulation unit.

3. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 2, characterized in that: A hydrogen product outlet temperature transmitter is arranged between the hydrogen separator and the electrolyzer.

4. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 2, characterized in that: A hydrogen thermometer is arranged on the hydrogen scrubber, and the hydrogen thermometer is fixedly connected to the hydrogen scrubber.

5. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 2, characterized in that: The outlet pipe of the hydrogen scrubber passes through the hydrogen precooler, and a hydrogen precooler air inlet valve and a hydrogen precooler bypass valve are fixedly arranged on the outlet pipe of the hydrogen scrubber.

6. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 1, characterized in that: The oxygen purification unit includes an oxygen separator, an oxygen cooler and an oxygen scrubber. The oxygen separator is connected to the upper part of the electrolytic cell, the lower part of the oxygen separator is connected to the lower part of the electrolytic cell through an alkali solution reflux unit, the oxygen cooler is connected to the oxygen separator, the upper part of the oxygen scrubber is connected to the oxygen cooler, the cooling water circulation unit is connected to the oxygen cooler, the pure water circulation unit is connected to the oxygen scrubber, and the lower part of the oxygen scrubber is connected to the oxygen separator through the pure water circulation unit.

7. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 6, characterized in that: An oxygen product outlet temperature transmitter is arranged between the oxygen separator and the electrolyzer.

8. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 6, characterized in that: An oxygen thermometer is arranged on the oxygen scrubber and is fixedly connected to the oxygen scrubber.

9. The energy-saving alkaline water electrolysis gas-liquid separation system according to claim 6, characterized in that: An oxygen scrubber exhaust valve is fixedly arranged on the outlet pipe of the oxygen scrubber, an oxygen scrubber bypass valve is arranged on one side of the oxygen scrubber exhaust valve, and two ends of the oxygen scrubber bypass valve are respectively fixedly connected to two ends of the oxygen scrubber exhaust valve.

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