A hydrogen-cooled power generation device with hydrogen online purification function and a hydrogen purification method

Abstract

The present invention provides a hydrogen-cooled power generation device with a hydrogen online purification function and a hydrogen purification method, comprising a catalytic deoxygenation module, an oil-gas separation module, a first membrane separation module, a second membrane separation module, an electrical control module, a gas replacement module, and a generator; the high-pressure side of the generator is connected to a catalytic deoxygenation module through a pipeline, the output end of the catalytic deoxygenation module is connected to an oil-gas separation module through a pipeline, the output end of the oil-gas separation module is connected to a first membrane separation module and a second membrane separation module through a pipeline, the first membrane separation module and the second membrane separation module are arranged in parallel, a passage is connected between the first membrane separation module and the second membrane separation module to enable multi-stage purification, and the output end where the first membrane separation module and the second membrane separation module meet is connected to the low-pressure side of the generator through a pipeline. The present invention can improve the hydrogen recovery rate while ensuring the purity of hydrogen purification through the arrangement of the above modules.

Description

Technical Field

[0001] The present invention relates to the field of gas purification and refining, and in particular to a hydrogen-cooled power generation device with a hydrogen online purification function and a hydrogen purification method. Background Art

[0002] Hydrogen has the remarkable characteristics of low density and high heat transfer coefficient. When used as a cooling medium for generators, it can reduce ventilation losses, improve heat exchange efficiency and reduce the insulation aging rate. However, during the operation of the generator, the purity of hydrogen will inevitably decrease due to factors such as hydrogen leakage, gas pollution and water mixing. According to the provisions of "DL / T 1164-2012 Steam Turbine Generator Operation Guidelines", the hydrogen purity in water-hydrogen-cooled and fully hydrogen-cooled generators should reach 96% (by volume) or above. In order to improve efficiency, it is best to operate at more than 98%, and the volume fraction of oxygen in hydrogen cannot exceed 0.5%. Once the hydrogen purity of the generator continues to be abnormal, it will not only reduce the cooling efficiency, increase ventilation losses, and cause local overheating, but it is more likely to cause a hydrogen explosion due to sparks generated by discharge.

[0003] In order to maintain high output of the generator, a variety of means are needed to maintain the hydrogen purity at more than 98%. Currently, a variety of methods have been used to improve the purity of hydrogen, such as increasing the frequency of hydrogen discharge and replenishment, installing hydrogen purification equipment, installing sealing oil filtration equipment, etc.; most power plants use hydrogen discharge and replenishment operations to solve the problem of low hydrogen purity, but when the hydrogen purity continues to decline, the frequency of hydrogen discharge and replenishment can be as high as 8h / time, indicating that simply increasing the number of hydrogen replenishments cannot fundamentally maintain hydrogen purity.

[0004] At present, some power plants have adopted hydrogen purification devices to improve the purity of hydrogen in generators, such as the comparative document with announcement number CN206069362U, which discloses a hydrogen-cooled generator set oil and gas separation and hydrogen purification and purification device, including a hydrogen input pipeline, an oil-water separator, an explosion-proof compressor, an air cooler, a filter, a heater, a gas separator and a hydrogen output pipeline. A maintenance pipeline is connected between the hydrogen input pipeline and the first gas pipeline. The maintenance pipeline is arranged in parallel with the oil-water separator, and a maintenance valve is provided on the maintenance pipeline. The device adopts a generator hydrogen purification device with an oil-water separation → filtration → gas separation process. Although the hydrogen purity can be increased to more than 99%, a small amount of hydrogen and separated oxygen still exist in the purified exhaust gas, and a deoxidizer is required for exhaust gas treatment, indicating that the hydrogen recovery rate of the device has not reached expectations, and the proportion of oxygen in the purified exhaust gas is relatively large. , which increases the safety hazard of the device; the purification efficiency of the hydrogen purification device is related to both the purity and recovery rate of hydrogen. Under the premise of ensuring the purity of the hydrogen after purification, the hydrogen recovery rate better reflects the economy of the purification device. Therefore, although the device can remove oil, water and impurity gases in hydrogen, its economy and purification efficiency are relatively low; the gas separator in the device simultaneously completes the separation of impurities such as oxygen, nitrogen, and water, which will increase the purification burden of the separation device, reduce its service life, and also affect its hydrogen recovery rate; in addition, the device uses traditional filters to remove a small amount of oil and water in hydrogen, and the filter element needs to be maintained and regenerated regularly. Not only can continuous online purification not be achieved, but it also increases the workload of the unit operation and maintenance personnel. The comparison document discloses that the dust filtration particle size is ≤0.01μm, and the higher filtration accuracy is more likely to cause clogging of the filter element, increasing the operation and maintenance workload of the device. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to improve the hydrogen recovery rate while ensuring the purity of hydrogen purification.

[0006] The present invention solves the above technical problems through the following technical means:

[0007] A hydrogen-cooled power generation device with a hydrogen online purification function comprises a catalytic deoxidation module (1), an oil-gas separation module (2), a first membrane separation module (3), a second membrane separation module (4), an electrical control module (5), a gas replacement module (6), and a generator (7); the generator (7) is provided with the gas replacement module (6); the high-pressure side of the generator (7) is connected to the catalytic deoxidation module (1) through a pipeline, the output end of the catalytic deoxidation module (1) is connected to the oil-gas separation module (2) through a pipeline, the output end of the oil-gas separation module (2) is connected to the first membrane separation module (3) and the second membrane separation module (4) through a pipeline, the first membrane separation module (3) and the second membrane separation module (4) are arranged in parallel, a passage is provided between the first membrane separation module (3) and the second membrane separation module (4) to enable multi-stage purification, and the output end where the first membrane separation module (3) and the second membrane separation module (4) meet is connected to the low-pressure side of the generator (7) through a pipeline; the generator (7) is provided with the electrical control module (5).

[0008] Beneficial effects: The purification process flow is optimized through the setting of catalytic deoxygenation module, oil and gas separation module, first membrane separation module, second membrane separation module, electrical control module, gas replacement module and generator, and the three steps of deoxygenation → water removal and oil removal → membrane separation are carried out in sequence. First, oxygen is removed to reduce the oxygen content in the device and eliminate safety hazards in the purification process. Subsequently, the oil and water impurities in the raw gas are simultaneously removed by the oil and gas separation module. Finally, other residual hydrocarbons, nitrogen and other impurity gases are removed by the membrane separation module. The membrane separation step can automatically switch to primary or secondary membrane separation to ensure the hydrogen recovery rate and purification effect of the device. The gas replacement module can replace the gas when the unit is shut down for maintenance.

[0009] Furthermore, the gas replacement module (6) comprises a first gas replacement valve (61), a second gas replacement valve (62), a third gas replacement valve (63), a fourth gas replacement valve (64), and a gas replacement pipeline corresponding to the number of replacement valves; the four valves and the replacement pipelines are respectively arranged around the generator (7), the third gas replacement valve (63) is connected to the high-pressure side of the generator (7) through the replacement pipeline, and the fourth gas replacement valve (64) is connected to the low-pressure side of the generator (7) through the replacement pipeline, and each of the replacement pipelines can be connected to a gas cylinder or a detection instrument.

[0010] Furthermore, the catalytic deoxidation module (1) comprises a first pneumatic valve (11), a first pressure gauge (12), a deoxidizer (13), and a hydrogen cooler (14); the first pneumatic valve (11) is connected to the high-pressure side of the generator (7) through a pipeline, and the first pressure gauge (12), the deoxidizer (13), and the hydrogen cooler (14) are sequentially connected to the back of the first pneumatic valve (11).

[0011] Beneficial effect: Through the setting of the first pneumatic valve, the first pressure gauge, the deoxidizer and the hydrogen cooler, the first pneumatic valve and the first pressure gauge cooperate to control the flow rate of the raw gas. The deoxidizer can reduce the oxygen concentration in the raw gas to below 1ppm. The hydrogen cooler can condense the water vapor generated by the previous process and the water vapor contained in the raw gas into liquid water, which enters the next module together with the raw gas.

[0012] Furthermore, the deoxidizer (13) has a built-in palladium-based catalyst.

[0013] Beneficial effect: By setting up a palladium-based catalyst, hydrogen and oxygen in the raw gas react to generate water, and the reaction can occur at room temperature.

[0014] Furthermore, a temperature measuring element is provided in the hydrogen cooler (14).

[0015] Beneficial effect: By setting the temperature measuring element, the temperature of the water vapor and raw gas in the hydrogen cooler can be measured, and the water vapor and raw gas are cooled to 25-40℃ before being discharged.

[0016] Furthermore, the oil-gas separation module (2) comprises a second pneumatic valve (21), a second pressure gauge (22), a two-phase separator (23), a third pneumatic valve (24), a compressor (25), and a drain valve (26); the second pneumatic valve (21) is connected to the catalytic deoxidation module (1); the second pressure gauge (22), the two-phase separator (23), the third pneumatic valve (24), and the compressor (25) are connected to the second pneumatic valve (21) in sequence; a drain port is provided at the bottom of the two-phase separator (23); a drain valve (26) is fixed to the drain port; and a liquid level sensor is provided in the two-phase separator (23).

[0017] Beneficial effects: Through the setting of the second pneumatic valve, the second pressure gauge, the two-phase separator, the third pneumatic valve, the compressor, and the drain valve, the second pneumatic valve and the second pressure gauge cooperate to control the flow rate of the raw gas. The compressor is used to pressurize the raw gas to make it reach the membrane entry pressure. The liquid level sensor monitors the separated liquid, and the bottom drain valve controls the discharge after reaching the discharge standard.

[0018] Furthermore, the two-phase separator (23) has a two-stage separation module built in, the first-stage module is provided with a vertical or inclined baffle to remove large droplets and oil droplets by gravity, and the second-stage module is provided with a vertical or inclined stainless steel filter to remove water vapor and oil mist by gravity.

[0019] Beneficial effect: Through the setting of the two-stage separation module, large droplets, oil droplets, water vapor and oil mist can flow into the two-phase separator by gravity and be discharged.

[0020] Furthermore, the compressor (25) is an explosion-proof compressor.

[0021] Beneficial effect: By setting up an explosion-proof compressor, the raw gas can be pressurized to reach the specified membrane entry pressure, while having higher safety.

[0022] Furthermore, the output end of the oil-gas separation module (2) is divided into two branch pipelines, one of which is fixed with a fourth pneumatic valve (31), and the other is fixed with a fifth pneumatic valve (41); the fourth pneumatic valve (31) is connected in sequence to a third pressure gauge (32), a first membrane separator (33), and a first hydrogen purity detector (34); the first membrane separator (33) is connected to a first exhaust valve (35) and a sixth pneumatic valve (42) through pipeline branches; after the free end of the sixth pneumatic valve (42) is connected to the fifth pneumatic valve (41), The sixth pneumatic valve (42) is connected in sequence to a fourth pressure gauge (43), a second membrane separator (44), and a second hydrogen purity detector (45); the second membrane separator (44) is connected to a second exhaust valve (47) and a seventh pneumatic valve (46) through pipeline branches; the free end of the seventh pneumatic valve (46) is connected to the pipeline between the fourth pneumatic valve (31) and the third pressure gauge (32); the pipelines after the first hydrogen purity detector (34) and the second hydrogen purity detector (45) are connected to the low-pressure side of the generator (7) after merging.

[0023] Beneficial effect: Through the arrangement of the fourth pneumatic valve, the third pressure gauge, the first membrane separator, the first hydrogen purity detector, the first exhaust valve, the fifth pneumatic valve, the sixth pneumatic valve, the fourth pressure gauge, the second membrane separator, the second hydrogen purity detector, the seventh pneumatic valve and the second exhaust valve, two-level separation can be achieved. When one of the membrane separation modules needs maintenance, the other membrane separation module can be replaced. When the membrane separator is maintained, only the equipment to be maintained is disconnected, and there is no need to shut down all the equipment for maintenance.

[0024] The present invention also discloses a method for purifying hydrogen using a hydrogen-cooled power generation device with an online hydrogen purification function as described in any of the above technical solutions, comprising the following steps:

[0025] S1 raw gas enters the catalytic deoxygenation module (1) from the high-voltage side of the generator (7). The catalyst in the catalytic deoxygenation module (1) causes the hydrogen and oxygen in the raw gas to react to generate water vapor. This reaction can occur at room temperature. The deoxygenated raw gas passes through the catalytic deoxygenation module (1) for cooling and condensation. The water vapor generated in the previous process and the water vapor contained in the raw gas are condensed into liquid water and enter the next module together with the raw gas.

[0026] S2 The raw gas purified by the catalytic deoxygenation module (1) flows into the oil-gas separation module (2), where liquid impurities such as water and oil are removed, and then enters the membrane separation process after being pressurized by the oil-gas separation module (2);

[0027] The S3 membrane separation process is divided into two modes:

[0028] Mode A: when the gas recovery rate of the first membrane separation module (3) is higher than 85%, only the first membrane separation module (3) is used for raw gas purification;

[0029] Mode B: When the gas recovery rate of the first membrane separation module (3) is lower than 85%, the first membrane separation module (3) and the second membrane separation module (4) are all put into operation, the first membrane separation module (3) performs primary separation, and the second membrane separation module (4) performs secondary separation;

[0030] S4: When the recovery rate of the first membrane separation module (3) continues to drop below 60%, the first membrane separation module (3) is disconnected for maintenance and overhaul; only the second membrane separation module (4) is put into operation, and the mode is switched to mode A to carry out S3; after the overhaul of the first membrane separation module (3) is completed and the recovery rate of the second membrane separation module (4) drops below 85%, the mode is switched to mode B in which the second membrane separation module (4) is used for primary separation and the first membrane separation module (3) is used for secondary separation to continue to complete S3.

[0031] Beneficial effects: Through the setting of the hydrogen purification method, the purification process flow is optimized, and the three steps of deoxygenation → water removal and oil removal → membrane separation are carried out in sequence. First, oxygen is removed to reduce the oxygen content in the device and eliminate safety hazards in the purification process. Subsequently, the oil and water impurities in the raw gas are removed simultaneously through the oil and gas separation module. Finally, other residual hydrocarbons, nitrogen and other impurity gases are removed by the membrane separation module. The membrane separation step can automatically switch to primary or secondary membrane separation to ensure the hydrogen recovery rate and purification effect of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of a hydrogen-cooled power generation device with a hydrogen online purification function according to a first embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of a hydrogen-cooled power generation device with an online hydrogen purification function according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Embodiment 1

[0036] like Figure 1 As shown, this embodiment provides a hydrogen-cooled power generation device with a hydrogen online purification function, including a catalytic deoxygenation module 1, an oil-gas separation module 2, a first membrane separation module 3, a second membrane separation module 4, an electrical control module 5, and a generator 7.

[0037] like Figure 1 As shown, a catalytic deoxygenation module 1 is provided on the high-pressure side of the generator 7 through a pipeline, an oil-gas separation module 2 is provided on the output end of the catalytic deoxygenation module 1 through a pipeline, a first membrane separation module 3 and a second membrane separation module 4 are provided on the output end of the oil-gas separation module 2 through a pipeline, the first membrane separation module 3 and the second membrane separation module 4 are provided in parallel, a passage is provided between the first membrane separation module 3 and the second membrane separation module 4 for multi-stage purification, the output end where the first membrane separation module 3 and the second membrane separation module 4 meet is provided on the low-pressure side of the generator 7 through a pipeline, an electrical control module 5 is connected to the pipeline on the low-pressure side of the generator 7, and the electrical control module 5 in this embodiment is an electrical control box.

[0038] like Figure 1As shown, the catalytic deoxidation module 1 includes a first pneumatic valve 11, a first pressure gauge 12, a deoxidizer 13, and a hydrogen cooler 14; the first pneumatic valve 11 is connected to the high-pressure side of the generator 7 through a pipeline, and the hydrogen (raw gas) before purification enters the catalytic deoxidation module 1 through the pipeline, the first pressure gauge 12, the deoxidizer 13 and the hydrogen cooler 14 are sequentially connected to the first pneumatic valve 11, and the first pneumatic valve 11 and the first pressure gauge 12 cooperate to control the flow rate of the raw gas; the deoxidizer 13 has a built-in catalyst, and the catalyst does not need to be replaced or regenerated. The catalyst in this embodiment is a palladium-based catalyst. Under the catalysis of the palladium-based catalyst The hydrogen and oxygen in the raw gas react to generate water. This reaction can occur at room temperature. The catalyst can reduce the oxygen concentration in the raw gas to below 1ppm. The oxidation reaction is a highly exothermic reaction. The deoxygenated raw gas enters the hydrogen cooler 14 to complete cooling and condensation. The water vapor generated by the previous process and the water vapor contained in the raw gas are condensed into liquid water and enter the next module together with the raw gas. A temperature measuring element (not shown) is fixed in the hydrogen cooler 14 to cool the water vapor and raw gas to 25-40°C and then discharge them. The hydrogen cooler 14 is used to maintain an appropriate film entry temperature, and the temperature measuring element is a prior art.

[0039] like Figure 1 As shown, the oil-gas separation module 2 includes a second pneumatic valve 21, a second pressure gauge 22, a two-phase separator 23, a third pneumatic valve 24, a compressor 25, and a drain valve 26; the second pneumatic valve 21 is connected after the hydrogen cooler 14, the second pressure gauge 22, the two-phase separator 23, the third pneumatic valve 24, and the compressor 25 are connected to the second pneumatic valve 21 in sequence, and the second pneumatic valve 21 cooperates with the second pressure gauge 22 to jointly control the flow rate of the raw gas; the compressor 25 is used to pressurize the raw gas to reach the membrane inlet pressure. The compressor 25 in this embodiment is an explosion-proof compressor, which can ensure safety when pressurizing the raw gas. Safety; a sewage outlet is provided at the bottom of the two-phase separator 23, and a sewage valve 26 is fixed on the sewage outlet; the two-phase separator 23 has a built-in two-stage separation module, the first-stage module is provided with a vertical or inclined baffle (not shown) to remove large droplets and oil droplets by gravity, and the second-stage module is provided with a vertical or inclined stainless steel filter (not shown) to remove water vapor and oil mist by gravity, and the separated liquid is monitored by a liquid level sensor (not shown) and is discharged from the bottom sewage outlet after meeting the sewage discharge standard, without stopping the machine to replace the filter element; the gas pipeline of the oil-gas separation module 2 in this embodiment is fixed with a thermal insulation layer to ensure that the hydrogen inlet membrane temperature is between 25 and 40°C.

[0040] like Figure 1As shown, the first membrane separation module 3 includes a fourth pneumatic valve 31, a third pressure gauge 32, a first membrane separator 33, a first hydrogen purity detector 34, and a first exhaust valve 35; the second membrane separation module 4 includes a fifth pneumatic valve 41, a sixth pneumatic valve 42, a fourth pressure gauge 43, a second membrane separator 44, a second hydrogen purity detector 45, a seventh pneumatic valve 46, and a second exhaust valve 47; the output end of the compressor 25 is divided into two branch pipelines, one pipeline is fixed with the fourth pneumatic valve 31, and the other pipeline is fixed with the fifth pneumatic valve 41; the third pressure gauge 32, the first membrane separator 33, and the first hydrogen purity detector 34 are connected to the fourth pneumatic valve 31 in sequence, and the first membrane separator 33 is respectively connected to the first exhaust valve 35 and the sixth pneumatic valve 42 through pipeline branches, and the free end of the sixth pneumatic valve 42 is connected to the fifth pneumatic valve 41, and the fourth pressure gauge 43, the second membrane separator 44 , the second hydrogen purity detector 45 is connected to the sixth pneumatic valve 42 in sequence, the second membrane separator 44 is connected to the second exhaust valve 47 and the seventh pneumatic valve 46 through pipeline branches, the free end of the seventh pneumatic valve 46 is connected to the pipeline between the fourth pneumatic valve 31 and the third pressure gauge 32, the pipelines after the first hydrogen purity detector 34 and the second hydrogen purity detector 45 are connected to the low-pressure side of the generator 7 after merging; the electrical control module 5 is connected to the pipeline after the first membrane separation module 3 and the second membrane separation module 4 are merged; the first membrane separator 33 and the second membrane separator 44 of this embodiment are of the same model, and a hollow fiber organic separation membrane with low price and good separation effect is adopted, and a measurement and control element is included, which can monitor the hydrogen recovery rate of the membrane separator online, and the first membrane separator 33 and the second membrane separator 44 are both existing technologies, which are used to separate dissolved gases such as nitrogen, methane, acetylene, etc.

[0041] like Figure 1 As shown, the electrical control module 5 is connected to all the pressure gauges, pneumatic valves and measurement and control elements of each module, and can realize basic functions such as controlling the valve opening according to the pressure signal, controlling the working parameters of the hydrogen cooler according to the temperature signal, controlling the membrane separation mode according to the hydrogen recovery rate signal, and the sound and light alarm for gas leakage. The control program of the electrical control module 5 is the existing technology.

[0042] The specific method for purifying hydrogen is as follows:

[0043] Step 1: The raw gas enters the catalytic deoxygenation module 1 from the high-pressure side of the generator 7; the hydrogen pressure of the generator 7 is usually 0.3-0.5 MPa, so the raw gas can enter the catalytic deoxygenation module 1 without being pressurized; the first pneumatic valve 11 and the first pressure gauge 12 jointly control the valve opening to adjust the gas flow. After the raw gas enters the catalytic deoxygenation module 1 at room temperature, it is first catalytically deoxidized by the deoxidizer 13. The deoxidizer 13 can react the hydrogen and oxygen in the raw gas to generate water under the catalysis of a palladium-based catalyst. The reaction can occur at room temperature and can reduce the oxygen concentration in the raw gas to below 1 ppm. Since this reaction is a highly exothermic reaction, the product will enter the next step in the form of water vapor together with the raw gas; the deoxygenated raw gas enters the hydrogen cooler 14 to complete cooling and condensation, and the water vapor generated by the previous process and the water vapor contained in the raw gas are condensed into liquid water and enter the next module together with the raw gas.

[0044] Step 2: The raw gas purified by the catalytic deoxygenation module 1 flows into the oil-gas separation module 2, and the second pneumatic valve 21 and the second pressure gauge 22 jointly control the valve opening to adjust the gas flow rate; then the raw gas passes through the two-phase separator 23 to remove liquid impurities such as water and oil, and enters the membrane separation process after being pressurized by the third pneumatic valve 24 and the explosion-proof compressor 25.

[0045] Step 3: The membrane separation process is divided into two modes:

[0046] Mode A: When the gas recovery rate monitored by the measurement and control element in the first membrane separator 33 is higher than 85%, only the first membrane separation module 3 is used for raw gas purification. At this time, the specific separation process is: open the fourth pneumatic valve 31, the fourth pneumatic valve 31 and the third pressure gauge 32 jointly control the membrane inlet flow, the raw gas is separated in the first membrane separator 33, the separated hydrogen is detected by the first hydrogen purity meter 34 and then enters the low-pressure side of the generator 7 to complete the purification process, and the exhaust gas is directly discharged through the first exhaust valve 35;

[0047] Mode B: When the gas recovery rate monitored by the measurement and control element in the first membrane separator 33 is lower than 85%, both membrane separators are put into operation. Taking the first membrane separation module 3 as the primary separation and the second membrane separation module 4 as the secondary separation as an example, the specific separation process is as follows: the fourth pneumatic valve 31 is opened, and the fourth pneumatic valve 31 and the third pressure gauge 32 jointly control the membrane flow rate. The raw gas completes the primary separation in the first membrane separator 33. The separated hydrogen enters the low-pressure side of the generator 7 after being detected by the first hydrogen purity meter 34. The tail gas enters the second membrane separation module 4 through the sixth pneumatic valve 42. The sixth pneumatic valve 42 and the fourth pressure gauge 43 jointly control the membrane flow rate. The secondary separation is completed in the second membrane separator 44. The separated hydrogen enters the low-pressure side of the generator 7 after being detected by the second hydrogen purity meter 45. The waste gas generated in the second membrane separator 44 is directly discharged by the second exhaust valve 47.

[0048] Step 4: When the recovery rate of the first membrane separation module 3 continues to drop below 60%, close the fourth pneumatic valve 31 and disconnect the first membrane separation module 3 for maintenance and overhaul; open the fifth pneumatic valve 41, only put the second membrane separation module 4 into operation, and switch to mode A to perform step 3; after the overhaul of the first membrane separation module 3 is completed and the recovery rate of the second membrane separation module 4 drops below 85%, switch to mode B with the second membrane separation module 4 as the primary separation and the first membrane separation module 3 as the secondary separation to continue to complete step 3.

[0049] The device can realize continuous online purification; the catalyst used in the deoxidizer 13 can be recycled without taking it out for replacement or replenishment; the two-phase separator 23 can discharge sewage online; when the membrane separator is overhauled, only the equipment to be overhauled is disconnected, and there is no need to shut down the entire device for overhaul; the operating temperature of the device is in the room temperature range (25-40°C), and only the residual heat of the reaction of the deoxidizer 13 and the hydrogen cooler 14 is used to maintain the operating temperature throughout the process, and the membrane inlet pressure of the membrane separator is maintained by a compressor 25, and there is no other temperature or pressure change operation, which effectively reduces the energy consumption of the device and reduces the difficulty of operating the device.

[0050] Embodiment 2

[0051] like Figure 2 As shown, the difference between this embodiment and the first embodiment is that, on the basis of the first embodiment, a hydrogen-cooled power generation device with an online hydrogen purification function further includes a gas replacement module 6, and the generator 7 is provided with a gas replacement module 6; the gas replacement module 6 includes a first gas replacement valve 61, a second gas replacement valve 62, a third gas replacement valve 63, a fourth gas replacement valve 64, and a gas replacement pipeline corresponding to the number of replacement valves; the four valves and the replacement pipelines are respectively arranged around the generator 7, the third gas replacement valve 63 is connected to the high-pressure side of the generator 7 through the replacement pipeline, and the fourth gas replacement valve 64 is connected to the low-pressure side of the generator 7 through the replacement pipeline; when performing gas replacement, the replacement pipeline can be connected to a gas cylinder (not shown) or a detection instrument (not shown).

[0052] During use, based on Example 1, the gas replacement process is as follows: when the unit needs to replace the gas of the generator 7 and each module due to shutdown and maintenance, the first gas replacement valve 61 and the second gas replacement valve 62 are opened, and the CO2 gas cylinder used for replacement is connected to the gas replacement pipeline, and the hydrogen in the generator 7 and each module is replaced with CO2; after the CO2 replacement is completed, the first gas replacement valve 61 and the second gas replacement valve 62 are closed, and the third gas replacement valve 63 and the fourth gas replacement valve 64 are opened, and compressed air is connected to replace the CO2 in the generator 7 and each module with compressed air to complete the gas replacement.

[0053] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hydrogen-cooled power generation device with hydrogen online purification function, characterized in that: It comprises a catalytic deoxidation module (1), an oil-gas separation module (2), a first membrane separation module (3), a second membrane separation module (4), an electrical control module (5), a gas replacement module (6), and a generator (7); The generator (7) is provided with a gas replacement module (6); a catalytic deoxidation module (1) is provided on the high-pressure side of the generator (7) through a pipeline, an oil-gas separation module (2) is provided on the output end of the catalytic deoxidation module (1) through a pipeline, a first membrane separation module (3) and a second membrane separation module (4) are provided on the output end of the oil-gas separation module (2) through a pipeline, the first membrane separation module (3) and the second membrane separation module (4) are provided in parallel, a passage is provided between the first membrane separation module (3) and the second membrane separation module (4) to enable multi-stage purification, and the output end where the first membrane separation module (3) and the second membrane separation module (4) meet is provided on the low-pressure side of the generator (7) through a pipeline; the generator (7) is provided with an electrical control module (5).

2. A hydrogen-cooled power generation device with hydrogen online purification function according to claim 1, characterized in that: The gas replacement module (6) comprises a first gas replacement valve (61), a second gas replacement valve (62), a third gas replacement valve (63), a fourth gas replacement valve (64), and a number of gas replacement pipelines corresponding to the replacement valves; the four valves and the replacement pipelines are respectively arranged around the generator (7); the third gas replacement valve (63) is connected to the high-pressure side of the generator (7) through the replacement pipeline; the fourth gas replacement valve (64) is connected to the low-pressure side of the generator (7) through the replacement pipeline; and each of the replacement pipelines can be connected to a gas cylinder or a detection instrument.

3. The hydrogen-cooled power generation device with online hydrogen purification function according to claim 1 is characterized in that: The catalytic deoxidation module (1) comprises a first pneumatic valve (11), a first pressure gauge (12), a deoxidizer (13), and a hydrogen cooler (14); the first pneumatic valve (11) is connected to the high-pressure side of the generator (7) through a pipeline, and the first pressure gauge (12), the deoxidizer (13), and the hydrogen cooler (14) are sequentially connected to the back of the first pneumatic valve (11).

4. A hydrogen-cooled power generation device with hydrogen online purification function according to claim 3, characterized in that: The deoxidizer (13) has a built-in palladium-based catalyst.

5. The hydrogen-cooled power generation device with hydrogen online purification function according to claim 3 is characterized in that: A temperature measuring element is arranged in the hydrogen cooler (14).

6. The hydrogen-cooled power generation device with hydrogen online purification function according to claim 1 is characterized in that: The oil-gas separation module (2) comprises a second pneumatic valve (21), a second pressure gauge (22), a two-phase separator (23), a third pneumatic valve (24), a compressor (25), and a drain valve (26); the second pneumatic valve (21) is connected after the catalytic deoxidation module (1); the second pressure gauge (22), the two-phase separator (23), the third pneumatic valve (24), and the compressor (25) are connected after the second pneumatic valve (21) in sequence; a drain port is provided at the bottom of the two-phase separator (23); a drain valve (26) is fixed on the drain port; and a liquid level sensor is provided in the two-phase separator (23).

7. A hydrogen-cooled power generation device with hydrogen online purification function according to claim 6, characterized in that: The two-phase separator (23) has a two-stage separation module built in. The first-stage module is provided with a vertical or inclined baffle to remove large liquid droplets and oil droplets by gravity, and the second-stage module is provided with a vertical or inclined stainless steel filter to remove water vapor and oil mist by gravity.

8. The hydrogen-cooled power generation device with hydrogen online purification function according to claim 6 is characterized in that: The compressor (25) is an explosion-proof compressor.

9. The hydrogen-cooled power generation device with hydrogen online purification function according to claim 1, characterized in that: The output end of the oil-gas separation module (2) is divided into two branch pipelines, one of which is fixed with a fourth pneumatic valve (31), and the other is fixed with a fifth pneumatic valve (41); the fourth pneumatic valve (31) is connected in sequence to a third pressure gauge (32), a first membrane separator (33), and a first hydrogen purity detector (34); the first membrane separator (33) is connected to a first exhaust valve (35) and a sixth pneumatic valve (42) through pipeline branches; after the free end of the sixth pneumatic valve (42) is connected to the fifth pneumatic valve (41), the first exhaust valve (35) and the sixth pneumatic valve (42) are connected to the fifth pneumatic valve (41). The sixth pneumatic valve (42) is connected in sequence to a fourth pressure gauge (43), a second membrane separator (44), and a second hydrogen purity detector (45); the second membrane separator (44) is connected to a second exhaust valve (47) and a seventh pneumatic valve (46) through pipeline branches; the free end of the seventh pneumatic valve (46) is connected to the pipeline between the fourth pneumatic valve (31) and the third pressure gauge (32); the pipelines after the first hydrogen purity detector (34) and the second hydrogen purity detector (45) are connected to the low-pressure side of the generator (7) after merging.

10. A method for purifying hydrogen using a hydrogen-cooled power generation device with an online hydrogen purification function as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1 raw gas enters the catalytic deoxygenation module (1) from the high-voltage side of the generator (7). The catalyst in the catalytic deoxygenation module (1) causes the hydrogen and oxygen in the raw gas to react to generate water vapor. This reaction can occur at room temperature. The deoxygenated raw gas passes through the catalytic deoxygenation module (1) for cooling and condensation. The water vapor generated in the previous process and the water vapor contained in the raw gas are condensed into liquid water and enter the next module together with the raw gas. S2 The raw gas purified by the catalytic deoxygenation module (1) flows into the oil-gas separation module (2), where liquid impurities such as water and oil are removed, and then enters the membrane separation process after being pressurized by the oil-gas separation module (2); The S3 membrane separation process is divided into two modes: Mode A: when the gas recovery rate of the first membrane separation module (3) is higher than 85%, only the first membrane separation module (3) is used for raw gas purification; Mode B: When the gas recovery rate of the first membrane separation module (3) is lower than 85%, the first membrane separation module (3) and the second membrane separation module (4) are all put into operation, the first membrane separation module (3) performs primary separation, and the second membrane separation module (4) performs secondary separation; S4: When the recovery rate of the first membrane separation module (3) continues to drop below 60%, the first membrane separation module (3) is disconnected for maintenance and overhaul; only the second membrane separation module (4) is put into operation, and the mode is switched to mode A to carry out S3; after the overhaul of the first membrane separation module (3) is completed and the recovery rate of the second membrane separation module (4) drops below 85%, the mode is switched to mode B in which the second membrane separation module (4) is used for primary separation and the first membrane separation module (3) is used for secondary separation to continue to complete S3.

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