Alkaline electrolytic cell adsorption hydrogen purification system and control method

Abstract

The present invention discloses an alkaline electrolytic cell adsorption hydrogen purification system and control method, belonging to the technical field of hydrogen purification in alkaline water electrolyzers. The system comprises a deoxygenation unit, an adsorption unit connected to the deoxygenation unit, and a drying unit connected to the adsorption unit; wherein the adsorption unit comprises: a housing; a holding cylinder; and a driver. In the invention application, a holding cylinder is provided so that the holding cylinder is divided into a plurality of fan-shaped cavities of equal size under a plurality of partitions. Each fan-shaped cavity is filled with adsorbent, and the adsorption zone, regeneration zone, and cooling zone within the housing are dynamically changed. The raw hydrogen flowing out of the gas-liquid separation system of the alkaline electrolytic cell is deoxygenated and adsorbed for dehydration. Part of the product hydrogen is used to achieve online continuous regeneration of the adsorbent, thereby solving the technical problems of complex system and unstable operation in the application of traditional hydrogen purification technology in the prior art and achieving the technical effect of adsorbent recycling.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen purification in alkaline water electrolyzers, and in particular to an alkaline electrolyzer adsorption hydrogen purification system and a control method. Background Art

[0002] Alkaline water electrolyzers have been widely used in large-scale hydrogen production from renewable energy sources such as wind and solar power due to their high technological maturity, low cost, and large-scale single-unit hydrogen production. The alkaline electrolyzer gas-liquid separation system is a key system for separating hydrogen and oxygen (gas) from the electrolysis product (solution) in the electrolyzer. In an alkaline water electrolyzer, water decomposes into hydrogen and oxygen. The hydrogen produced on the cathode side of the electrolyzer typically contains impurities, primarily water vapor and a small amount of oxygen. These impurities directly impact the high-purity hydrogen requirements of downstream industries. The current mainstream hydrogen purification method utilizes catalytic deoxygenation and a three-tower adsorption drying process. Catalytic deoxygenation effectively removes oxygen from the hydrogen. The hydrogen is then further purified by a three-tower adsorption drying process. This process utilizes three adsorption towers for sequential adsorption drying, adsorbent regeneration, and adsorbent cooling, ensuring high hydrogen purity and zero hydrogen waste. Existing hydrogen purification systems often require complex control due to frequent switching between the three adsorption towers and the use of numerous automatic valves, resulting in complex control and a high failure rate. Summary of the Invention

[0003] The purpose of the present invention is to solve the shortcomings of the prior art, such as complex system and unstable operation, and to propose an alkaline electrolytic cell adsorption method hydrogen purification system.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A first aspect of the present invention provides an alkaline electrolytic cell adsorption hydrogen purification system, comprising: a deoxygenation unit, an adsorption unit connected to the deoxygenation unit, and a drying unit connected to the adsorption unit;

[0006] Wherein, the adsorption unit comprises:

[0007] a housing, the housing being in communication with the deoxidation unit and the drying unit, the housing being in a cylindrical structure with a cavity inside;

[0008] a containing cylinder, the containing cylinder being movably disposed in the shell and adapted to fit the shell;

[0009] A driver, the driver is fixedly disposed on the housing, and an output end of the driver is fixedly connected to the holding cylinder, for providing power to drive the holding cylinder to rotate;

[0010] The deoxidation unit comprises:

[0011] a first heat exchanger, the first heat exchanger being connected to the hydrogen outlet of the gas-liquid separation system of the alkaline electrolyzer, and the first heat exchanger being used for heat exchange treatment of the raw hydrogen;

[0012] a deoxidizer, the deoxidizer being connected to the first heat exchanger and filled with a catalyst for removing impurity oxygen in the raw hydrogen;

[0013] a first heater, which is disposed on a pipeline between the first heat exchanger and the deoxidizer, and is used to heat the raw hydrogen;

[0014] a first cooler, the first cooler being in communication with the first heat exchanger and being configured to cool the deoxygenated hydrogen;

[0015] a first gas-water separator, one end of the first gas-water separator being connected to the first cooler, and the other end being connected to the adsorption unit, and the first gas-water separator being used to separate and remove condensed water from the deoxygenated hydrogen;

[0016] The cavity within the shell is provided with three sets of sealing elements arranged circumferentially and spaced apart and fixed on the inner side of the shell, and the three sealing elements divide the shell into an adsorption zone, a regeneration zone and a cooling zone; the regeneration zone is also provided with a temperature sensor for monitoring temperature and transmitting signals;

[0017] The holding cylinder is provided with a plurality of partitions adapted to the sealing element, the plurality of partitions dividing the holding cylinder into a plurality of fan-shaped cavities of equal size, and the adsorbent is filled in each fan-shaped cavity;

[0018] The rotation direction of the containing cylinder is from the adsorption zone to the regeneration zone and then to the cooling zone.

[0019] In some feasible embodiments, the shell is further connected to a hydrogen main pipe, and the hydrogen main pipe is adapted to the adsorption area, and a pressure regulating valve is provided on the hydrogen main pipe.

[0020] In some feasible embodiments, the drying unit includes a hydrogen branch pipe, which is connected to the hydrogen main pipe, and the regenerated hydrogen flows into the drying unit through the hydrogen branch pipe;

[0021] The hydrogen branch pipe is provided with a flow regulating valve, and the flow regulating valve is electrically connected to the temperature sensor.

[0022] In some feasible embodiments, the drying unit further includes:

[0023] a second heat exchanger, one end of which is connected to the hydrogen branch pipe, and the second heat exchanger is used to perform primary heating and primary cooling on the regenerated hydrogen;

[0024] a second heater, one end of the second heater being connected to the second heat exchanger and the other end being connected to the regeneration zone, the second heater being used for performing secondary heating on the regenerated hydrogen;

[0025] a second cooler, the second cooler being in communication with the second heat exchanger and configured to perform secondary cooling on the regenerated hydrogen;

[0026] A second gas-water separator, one end of which is connected to the second cooler, and the other end of which is connected to the cooling zone, is used to separate and remove condensed water in the regenerated hydrogen.

[0027] In some feasible embodiments, the adsorbent filled in the containing cylinder is divided into two layers of composite adsorbent, the upper layer adopts molecular sieve or similar adsorbent, and the lower layer adopts activated alumina or similar adsorbent.

[0028] A second aspect of the present invention provides a control method for an alkaline electrolytic cell adsorption hydrogen purification system, which employs an alkaline electrolytic cell adsorption hydrogen purification system according to any one of the first aspects, and the control method further comprises:

[0029] S1: introducing raw hydrogen, deoxidizing, dehydrating and adsorbing the raw hydrogen to obtain product hydrogen;

[0030] S2: According to the saturation level of the adsorbent in the adsorption area, the driver is started intermittently to drive the containing cylinder to rotate and replace the adsorbent in the adsorption area.

[0031] S3. According to the temperature deviation value in the regeneration zone, the flow rate of the regenerated hydrogen is adjusted through the flow control valve;

[0032] S31, obtaining the temperature deviation value in the regeneration zone;

[0033] Among them, temperature deviation value = actual temperature value - preset temperature value;

[0034] S32, adjusting the flow rate of the regenerated hydrogen based on the temperature deviation value;

[0035] The regulating the flow rate of the regenerated hydrogen based on the temperature deviation value includes:

[0036] S321, generating regeneration hydrogen flow adjustment information based on the temperature deviation value and the first temperature deviation threshold;

[0037] The first adjustment information of the regeneration hydrogen flow rate is generated based on the temperature deviation value and the first temperature deviation threshold by comparing the temperature deviation value with the first temperature deviation threshold, and generating the regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the first temperature deviation threshold;

[0038] Generating regeneration hydrogen flow adjustment information based on the temperature deviation value and the first temperature deviation threshold includes:

[0039] S322, generating first regeneration hydrogen flow adjustment information based on the temperature deviation value and the second temperature deviation threshold;

[0040] The second regeneration hydrogen flow rate adjustment information is generated based on the temperature deviation value and the second temperature deviation threshold by comparing the temperature deviation value with the second temperature deviation threshold, and generating the first regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the first temperature deviation threshold and is less than the second temperature deviation value;

[0041] The first regenerated hydrogen flow adjustment information includes:

[0042] The flow rate of the regenerated hydrogen is adjusted based on the temperature deviation value and the second temperature deviation threshold value, specifically in the following manner:

[0043] ;

[0044] in, is the regeneration hydrogen flow rate obtained at the current time point, is the regenerated hydrogen flow rate at the previous time point, is the temperature deviation value, is the set second temperature deviation threshold;

[0045] S323, generating second regeneration hydrogen flow adjustment information based on the temperature deviation value and the third temperature deviation threshold;

[0046] The second regeneration hydrogen flow rate adjustment information is generated based on the temperature deviation value and the third temperature deviation threshold by comparing the temperature deviation value with the third temperature deviation threshold, and generating the second regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the second temperature deviation threshold and is less than the third temperature deviation threshold;

[0047] The generating of the second regeneration hydrogen flow rate adjustment information includes:

[0048] The flow rate of regenerated hydrogen is adjusted based on the temperature deviation value. The specific method is as follows:

[0049] ;

[0050] in, is the flow rate of regenerated hydrogen; is the proportionality coefficient; is the integration coefficient, is the differential coefficient, is the sampling time;

[0051] The integration coefficient The calculation method is:

[0052] ;

[0053] in, is the final integration coefficient, is the integral amplitude from 0 to time t, are the minimum integral coefficient and the maximum integral coefficient respectively.

[0054] The method of adjusting the flow rate of the regenerated hydrogen based on the temperature deviation value further includes:

[0055] S324, generating third regeneration hydrogen flow adjustment information based on the temperature deviation value and the third temperature deviation threshold;

[0056] The third regeneration hydrogen flow rate adjustment information is generated based on the temperature deviation value and the third temperature deviation threshold by comparing the temperature deviation value with the third temperature deviation threshold, and generating the third regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the third temperature deviation threshold;

[0057] The method for adjusting the regeneration hydrogen flow rate based on the temperature deviation value and the third temperature deviation threshold is:

[0058]

[0059] in, is the proportional term, is the integral term, is the differential term, They are the set minimum and maximum flow thresholds respectively;

[0060] In the present application, the outer shell is divided into an adsorption zone, a regeneration zone and a cooling zone, and the containing cylinder is divided into a number of fan-shaped cavities of equal size under a number of partitions. Each fan-shaped cavity is filled with adsorbent, and circulates in the adsorption zone, regeneration zone and cooling zone in the outer shell, continuously adsorbing and removing water from the raw hydrogen, and utilizing part of the product hydrogen as regenerated hydrogen to realize online continuous regeneration and cooling of the adsorbent, thereby solving the technical problems of complex system and unstable operation in the prior art and achieving the technical effect of recycling the adsorbent. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is a schematic diagram of the overall structure of an alkaline electrolytic cell adsorption method hydrogen purification system provided in an embodiment of the present invention.

[0062] The markings in the figure are as follows:

[0063] 1. Deoxygenation unit; 11. First heat exchanger; 12. Deoxygenator; 13. First heater; 14. First cooler; 15. First gas-water separator;

[0064] 2. Adsorption unit; 21. Housing; 211. Adsorption zone; 212. Regeneration zone; 213. Cooling zone; 22. Container; 221. Partition; 23. Driver;

[0065] 3. Drying unit; 31. Second heat exchanger; 32. Second heater; 33. Second cooler; 34. Second gas-water separator;

[0066] 4. Hydrogen main pipe; 41. Pressure regulating valve;

[0067] 5. Hydrogen branch pipe; 51. Flow regulating valve. DETAILED DESCRIPTION

[0068] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0069] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0070] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0071] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0072] See also Figure 1 As shown, in order to solve the shortcomings of the prior art such as complex system and unstable operation, the first aspect of the present invention provides an alkaline electrolytic cell adsorption method hydrogen purification system in an embodiment, including a deoxygenation unit 1, an adsorption unit 2 connected to the deoxygenation unit, and a drying unit 3 connected to the adsorption unit 2.

[0073] Specifically, the deoxygenation unit 1 is connected to the hydrogen outlet of the gas-liquid separation system of the alkaline electrolyzer, and the raw hydrogen enters the deoxygenation unit 1 through this outlet. The deoxygenation unit 1 is used to deoxygenate and purify the raw hydrogen. It can be understood that the raw hydrogen refers to the hydrogen produced by the gas-liquid separation system of the alkaline electrolyzer, which is doped with impurities such as oxygen and water vapor.

[0074] In this embodiment, the deoxygenation unit 1 includes a first heat exchanger 11, a deoxygenator 12 and a first cooler 14 connected to the first heat exchanger 11, a first heater 13 arranged between the first heat exchanger 11 and the deoxygenator 12, and a first gas-water separator 15 connected to the first cooler 14.

[0075] The first heat exchanger 11 includes a first air inlet, a first air outlet, a second air inlet, and a second air outlet. The first air inlet is connected to the hydrogen outlet of the gas-liquid separation system of the alkaline electrolyzer, and the raw hydrogen enters the first heat exchanger 11 through the first air inlet for heat exchange.

[0076] The air inlet end of the deoxidizer 12 is connected to the first air outlet of the first heat exchanger 11, and the air outlet end of the deoxidizer 12 is connected to the second air inlet of the first heat exchanger 11. The deoxidizer 12 is filled with a catalyst. After the raw hydrogen enters the deoxidizer 12, under the action of the catalyst, the impurity oxygen in the raw hydrogen reacts with the hydrogen to generate water, thereby removing the impurity oxygen in the raw hydrogen. In some preferred embodiments, the catalyst can be, but is not limited to, a palladium catalyst, or a platinum catalyst or other catalyst with stable catalytic performance and strong activity, so that the impurity oxygen in the raw hydrogen reacts with the hydrogen more quickly and fully, thereby improving production efficiency. In addition, the air outlet end of the deoxidizer 12 is connected to the second air inlet of the first heat exchanger 11, so that a loop is formed between the first heat exchanger 11 and the deoxidizer 12, and the deoxygenated hydrogen flowing out after the raw hydrogen passes through the deoxidizer 12 is deoxygenated and flows back to the first heat exchanger 11 through the second air inlet for cooling.

[0077] Since the catalyst reacts more rapidly under high temperature conditions, in order to improve the catalytic efficiency of the catalyst in the deoxidizer 12, a first heater 13 is further provided on the pipeline between the first heat exchanger 11 and the deoxidizer 12. After the raw hydrogen flows out of the first gas outlet, it is heated by the first heater 13. After the raw hydrogen is heated to a set temperature by the first heater 13, it flows into the deoxidizer 12, so that the impurity oxygen in the raw hydrogen reacts with the hydrogen more rapidly under the action of the catalyst.

[0078] The first cooler 14 is connected to the second gas outlet of the first heat exchanger 11. After the raw hydrogen reacts in the deoxidizer 12, deoxygenated hydrogen is obtained. The deoxygenated hydrogen is refluxed into the first heat exchanger 11, where it is cooled by heat exchange. The deoxygenated hydrogen then flows into the first cooler 14 for secondary cooling, so that the water vapor in the deoxygenated hydrogen is cooled into condensed water. It can be understood that the deoxygenated hydrogen refers to the hydrogen obtained after the raw hydrogen is deoxygenated, which does not contain impurity oxygen but contains water vapor.

[0079] The inlet end of the first gas-water separator 15 is connected to the first cooler 14, and the outlet end is connected to the adsorption unit 2. The first gas-water separator 15 is used to separate and remove condensed water from the deoxygenated hydrogen. Since the deoxygenated hydrogen still contains a small amount of water, the deoxygenated hydrogen flowing out of the first gas-water separator 15 enters the adsorption unit 2 to remove the water through adsorption, resulting in dry product hydrogen. It is understood that the product hydrogen refers to pure hydrogen with a purity of 99.8% or higher after the impurities of oxygen and water are removed.

[0080] The adsorption unit 2 is connected to the deoxygenation unit 1. After being purified by the deoxygenation unit 1, the raw hydrogen enters the adsorption unit 2 for further dehydration, drying, and purification to obtain the product hydrogen. Specifically, the adsorption unit 2 includes a housing 21 and a container 22 disposed within the housing 21.

[0081] In this embodiment, the housing 21 is cylindrical in structure, with an enclosed cavity within. The housing 21 is used to protect internal components from external environmental factors (such as dust, corrosive gases, etc.), thereby increasing the service life of the device. The cavity within the housing 21 is divided into three independent regions. For example, the cavity within the housing 21 is provided with three sets of sealing elements arranged circumferentially and fixed to the inner side of the housing 21. The three sealing elements separate the housing 21 into an adsorption zone 211, a regeneration zone 212, and a cooling zone 213. The sealing elements also prevent cross-flow between the adsorption zone 211, the regeneration zone 212, and the cooling zone 213. The housing 21 is also provided with a first air inlet and a first air outlet adapted for the adsorption zone 211, a second air inlet and a second air outlet adapted for the regeneration zone 212, and a third air inlet and a third air outlet adapted for the cooling zone 213.

[0082] Specifically, the adsorption zone 211 is used to adsorb water vapor in the deoxygenated hydrogen, and the regeneration zone 212 is used to perform high-temperature desorption regeneration on the adsorbent. The cooling zone 213 is used to deeply adsorb and remove water vapor in the regenerated hydrogen to obtain high-purity dry hydrogen product, and to cool the adsorbent after desorption and regeneration.

[0083] The holding cylinder 22 is disposed within the cavity of the outer shell 21. Several partitions compatible with the sealing element are disposed within the holding cylinder 22. The partitions are evenly distributed radially within the holding cylinder 22, and the partitions are fixedly connected at one end located at the center of the holding cylinder 22, thereby dividing the holding cylinder 22 into several fan-shaped cavities of equal size. These fan-shaped cavities together constitute the holding cylinder 22. Each fan-shaped cavity is filled with an adsorbent for adsorbing water vapor. The first air inlet on the outer shell 21 is connected to the air outlet of the first gas-water separator 15. After the deoxygenated hydrogen flows out of the first gas-water separator 15, it flows through the first air inlet into the adsorption zone 211. The adsorbent in the fan-shaped cavities within the adsorption zone 211 adsorbs and removes water vapor from the deoxygenated hydrogen, thereby producing product hydrogen.

[0084] In this embodiment, the adsorbent in each fan-shaped cavity in the containing cylinder 22 is divided into two layers of composite adsorbents, the lower layer adopts activated alumina or other similar adsorbents. Activated alumina has high adsorption capacity and fast adsorption speed, and has strong adsorption capacity for water vapor and other polar substances. The upper layer adopts molecular sieve or other similar adsorbents. Molecular sieve has a unique pore structure and can efficiently separate gas molecules of different sizes and properties. In the pressure swing adsorption process, the molecular sieve can preferentially adsorb molecules with smaller diameters, thereby achieving the enrichment of target molecules. Through the layered adsorption of the upper and lower layers, the different characteristics of the two adsorbents are utilized to achieve synergistic effects and improve the adsorption efficiency. Both activated alumina and molecular sieve can be reused through appropriate regeneration treatment (such as high-temperature heating desorption), thereby reducing operating costs.

[0085] In some preferred embodiments, in order to simplify the structure and reduce costs, the adsorbent in each fan-shaped cavity in the containing cylinder 22 can also be arranged in a non-layered manner, that is, the adsorbent is entirely made of activated alumina, molecular sieve or other similar adsorbents, so as to simplify the operation and improve convenience in actual application.

[0086] In this embodiment, the housing 21 is further connected to a hydrogen main pipe 4, which is adapted to the adsorption zone 211. Specifically, the hydrogen main pipe 4 is connected to the first gas outlet of the adsorption zone. The hydrogen product, after dehydration by adsorption in the adsorption zone 211, flows from the first gas outlet into the hydrogen main pipe 4 and is then transported to a hydrogen storage tank for storage. A pressure regulating valve 41 is also provided on the hydrogen main pipe 4. The pressure regulating valve 41 is used to regulate and control the pressure of a fluid, such as a gas. For example, by reducing the opening of the pressure regulating valve 41, the output pressure of the hydrogen main pipe 4 can be reduced.

[0087] In this embodiment, to desorb and regenerate the adsorbent, the drying unit 3 is connected to the regeneration zone 212 within the adsorption unit 23. The drying unit includes a hydrogen branch pipe 5, one end of which is connected to the hydrogen main pipe 4. By introducing a portion of the product hydrogen as regeneration hydrogen into the regeneration zone 212, the adsorbent within the regeneration zone 212 is subjected to online desorption and regeneration. It should be understood that the regeneration hydrogen refers to the portion of the product hydrogen that enters the drying unit 3 through the hydrogen branch pipe 5.

[0088] Preferably, a flow regulating valve 51 is provided on the hydrogen branch pipe 5. The flow regulating valve 51 is used to control the flow of regenerated hydrogen. The flow regulating valve 51 includes but is not limited to common regulating valves such as butterfly valves, stop valves, gate valves and throttle valves. The flow of regenerated hydrogen is controlled by changing the size or shape of the flow channel in the valve body.

[0089] Specifically, the drying unit 3 further includes a second heat exchanger 31 , a second heater 32 and a second cooler 33 connected to the second heat exchanger 31 , and a second gas-water separator 34 connected to the second cooler 33 .

[0090] More specifically, the second heat exchanger 31 includes a third air inlet, a third air outlet, and a fourth air inlet and a fourth air outlet. The third air inlet is connected to the hydrogen branch pipe 5, and the third air outlet is connected to the second air inlet, so that the regenerated hydrogen enters the second heat exchanger 31 for heat exchange treatment before flowing into the regeneration zone 212.

[0091] To heat the regenerated hydrogen, the second heater 32 is located in the pipeline between the second heat exchanger 31 and the regeneration zone 212. Before entering the regeneration zone 212, the regenerated hydrogen is heated by the second heater 32, reaching a temperature suitable for adsorbent desorption and regeneration. The regenerated hydrogen then flows into the regeneration zone 212, where the high-temperature regenerated hydrogen is used to perform high-temperature desorption and regeneration of the adsorbent. To facilitate real-time monitoring of the temperature within the regeneration zone 212, a temperature sensor is also located within the regeneration zone 212. The temperature sensor is electrically connected to the flow control valve 51. When the temperature sensor detects a temperature change within the regeneration zone 212, it transmits a signal to the controller, which controls the opening of the flow control valve 51, thereby adjusting the flow of regenerated hydrogen and maintaining a stable temperature within the regeneration zone 212.

[0092] The second gas outlet end corresponding to the regeneration zone 212 is connected to the fourth gas inlet of the second heat exchanger 31, so that the regenerated hydrogen forms a loop between the regeneration zone 212 and the second heat exchanger 31, and the regenerated hydrogen flowing out of the regeneration zone 212 flows back into the second heat exchanger 31 through the fourth gas inlet for heat exchange again. For example, since the regenerated hydrogen is heated by the second heater 32, its temperature is higher than the temperature of the regenerated hydrogen when it passes through the third gas inlet in the second heat exchanger 32. Therefore, the regenerated hydrogen flowing into the second heat exchanger 31 through the fourth gas inlet and the regenerated hydrogen flowing into the second heat exchanger 31 through the third gas inlet can be heat exchanged in the second heat exchanger 31 to reduce the heat of the regenerated hydrogen flowing into the second heat exchanger 31 from the fourth gas inlet.

[0093] The air inlet end of the second cooler 33 is connected to the fourth air outlet. Since the regenerated hydrogen contains water vapor after high-temperature desorption of the adsorbent in the regeneration zone 212, the regenerated hydrogen is cooled by heat exchange and then subjected to secondary cooling through the second cooler 33 to convert the water vapor in the regenerated hydrogen into condensed water.

[0094] The inlet end of the second gas-water separator 34 is connected to the outlet end of the second cooler 33. The second gas-water separator 34 is used to separate and remove condensed water from the regenerated hydrogen. The second gas-water separator 34 is connected to the third inlet end. After the condensed water is removed, the regenerated hydrogen flows into the cooling zone 213. On the one hand, the cooled regenerated hydrogen cools the adsorbent in the cooling zone 213. On the other hand, to prevent the regenerated hydrogen from containing a small amount of water, which may reduce the purity of the regenerated hydrogen, the adsorbent in the cooling zone 213 absorbs and removes water, allowing the regenerated hydrogen to regenerate into product hydrogen.

[0095] The third gas outlet is connected to the hydrogen main pipe 4, so that the product hydrogen generated by the regenerated hydrogen is sent to the hydrogen storage tank by the hydrogen main pipe 4 for storage, and the regenerated hydrogen flowing out of the cooling zone 213 is directly connected to a section of the hydrogen main pipe 4 after the pressure regulating valve 41, so that the outlet pressure of the regenerated hydrogen flowing out of the cooling zone 213 and merging into the hydrogen main pipe 4 remains consistent.

[0096] In some preferred embodiments, the first heater 13 and the second heater 32 are both electric heaters. For example, the electric heaters include electric heating tubes, electric heating films and other equipment, which are existing technologies. The electric heaters can directly convert electrical energy into thermal energy, have high heating efficiency and fast response speed, so as to improve work efficiency.

[0097] In some preferred embodiments, the first cooler 14 and the second cooler 33 are both water-cooled structures. For example, the water-cooled structure is one of a plate water cooler, a tubular water cooler, and a spiral water cooler. The structure is compact, convenient for daily maintenance, and has high cooling efficiency, so as to provide a stable and efficient heat dissipation effect for the raw hydrogen and the regenerated hydrogen.

[0098] In some preferred embodiments, the first gas inlet is located at the bottom of the adsorption zone 211, the first gas outlet is located at the top of the adsorption zone 211, the second gas inlet is located at the top of the regeneration zone 212, the second gas outlet is located at the bottom of the regeneration zone 212, the third gas inlet is located at the bottom of the cooling zone 213, and the third gas outlet is located at the top of the cooling zone 213. That is, the raw hydrogen enters the adsorption zone 211 from bottom to top, the regenerated hydrogen enters the regeneration zone 212 from top to bottom, and the regenerated hydrogen enters the cooling zone 213 from bottom to top. Since the adsorbent is filled to a certain thickness in each sector-shaped cavity of the holding cylinder 22, as the raw hydrogen gradually flows from bottom to top through the adsorbent layer in the adsorption zone 211, the water vapor in the raw hydrogen will gradually be adsorbed by the adsorption layer, and the water vapor content will gradually decrease. The amount of water adsorbed by the adsorbent layer from bottom to top will also gradually decrease. The extended adsorption time will ensure that the hydrogen that eventually flows out of the adsorption zone 211 will have a lower water content, thereby improving the quality and stability of the product. When the high-temperature regenerated hydrogen flows through the adsorbent layer in the regeneration zone 212, the adsorbent in the uppermost layer can first obtain a good desorption regeneration effect, because at this time the temperature of the regenerated hydrogen entering the regeneration zone 212 is higher and the water vapor content in the regenerated hydrogen is the lowest, making the upper adsorbent in the regeneration zone 212 have a stronger regeneration capacity. As the high-temperature hydrogen flows from top to bottom, the heat is evenly transferred from the upper adsorbent to the lower adsorbent, achieving uniform heat distribution. When the raw hydrogen and the regenerated hydrogen are adsorbed, their flow directions are exactly opposite, so that the adsorbent has better adsorption performance for the raw hydrogen flowing from bottom to top, and the product hydrogen obtained after adsorption has higher purity.

[0099] In this embodiment, in order to recycle the adsorbent, the holding cylinder 22 is movably connected to the outer shell 21, that is, the holding cylinder 22 can rotate in the cavity. The holding cylinder 22 has a cylindrical structure that is compatible with the outer shell 21, so that after the holding cylinder 22 rotates a set angle, the partition in the holding cylinder 22 and the sealing element between two adjacent areas in the outer shell 21 (for example, the sealing element between the adsorption zone 211 and the regeneration zone 212) will form a sealing surface to reduce the possibility of mutual cross-flow of air flows between the adsorption zone 211, the regeneration zone 212 and the cooling zone 213.

[0100] Specifically, the rotation direction of the holding cylinder 22 is from the adsorption zone 211 to the regeneration zone 212, and then to the cooling zone 213, and is intermittently rotated in this direction to make the adsorbent more efficient in adsorption and water removal, and the regeneration and desorption more complete. For example, when the holding cylinder 22 starts to rotate from a stationary state, several fan-shaped cavities located in the adsorption zone 211 rotate to the regeneration zone 212, several fan-shaped cavities located in the regeneration zone 212 rotate to the cooling zone 213, and several fan-shaped cavities located in the cooling zone 213 rotate to the adsorption zone 211, and this is a cycle, so that the adsorbent in each fan-shaped cavity can complete the corresponding operation in the corresponding adsorption zone 211, regeneration zone 212 and cooling zone 213, thereby realizing the periodic cycle process of online continuous adsorption, regeneration and cooling of the adsorbent.

[0101] The adsorption unit further includes a driver 23, which is fixedly mounted on the housing 21, and an output end of the driver 23 is fixedly connected to the holding cylinder 22. Activating the driver 23 can drive the holding cylinder 22 to rotate within the housing 21. Preferably, the driver 23 can be, but is not limited to, an electric motor, or other power-providing structure. For example, to achieve periodic rotation of the holding cylinder 22, the motor is a stepping motor, which includes components such as coil windings, a stator, and a rotor. Precise rotation is achieved by controlling the electromagnetic field generated by the energized stator windings in sequence and adjusting the rotor position, thereby controlling the rotation angle of the holding cylinder 22 connected thereto and the interval time of each rotation, thereby achieving precise control of the rotation of the rotating cylinder.

[0102] In this embodiment, the housing 21 is divided into an adsorption zone 211, a regeneration zone 212, and a cooling zone 213, and the holding cylinder 22 is divided into a plurality of sector-shaped cavities of equal size by the partitioning action of a plurality of partitions. Adsorbent is filled in each sector-shaped cavity, and the deoxygenated hydrogen is adsorbed and dehydrated by the adsorbent in the adsorption zone 211. Part of the product hydrogen is used as regenerated hydrogen to achieve online continuous regeneration and cooling of the adsorbent. This solves the technical problems of complex application systems and unstable operation of hydrogen purification technologies in the prior art, and achieves the technical effect of adsorbent recycling.

[0103] See also Figure 1 As shown, the second aspect of the present invention in this embodiment further provides a control method for an alkaline electrolytic cell adsorption hydrogen purification system. The control method adopts the alkaline electrolytic cell adsorption hydrogen purification system provided in the first aspect, and the control method includes:

[0104] S1: introducing raw hydrogen, deoxidizing, dehydrating and adsorbing the raw hydrogen to obtain product hydrogen;

[0105] In this step, the raw hydrogen gas flows continuously into the first heat exchanger 11 through the hydrogen outlet of the alkaline electrolyzer gas-liquid separation system. After heat exchange in the first heat exchanger 11 and secondary heating in the first heater 13, it flows into the deoxidizer 12 for deoxygenation to produce deoxygenated hydrogen. The deoxygenated hydrogen gas flows back into the first heat exchanger 11 for heat exchange again, undergoes primary cooling to remove oxygen, and then enters the first cooler 14 for secondary cooling. The cooled raw hydrogen gas enters the first gas-water separator 15 to separate and remove condensed water. It then flows into the adsorption zone 211 within the adsorption unit 2 for adsorption removal to produce product hydrogen. The product hydrogen is then transported to the hydrogen storage tank via the hydrogen main pipe 4 for storage.

[0106] S2: According to the saturation level of the adsorbent in the adsorption area 211 , the driver 23 is started intermittently to drive the containing cylinder 22 to rotate and replace the adsorbent in the adsorption area 211 .

[0107] In this step, the saturation level of the adsorbent in the adsorption zone 211 can be set based on historical data or experimental analysis. When the amount of deoxygenated hydrogen introduced into the adsorption zone 211 exceeds the adsorption threshold set for the adsorbent, it indicates that the adsorbent has reached saturation and the adsorbent in the adsorption zone 211 needs to be replaced.

[0108] The method for replacing the adsorbent in the adsorption zone 211 is as follows: at this time, the driver 23 is started to drive the holding cylinder 22 to rotate, and the fan-shaped cavity in the area corresponding to the adsorption zone 211 in the holding cylinder 22 rotates to the regeneration zone 212 to desorb and regenerate the adsorbent. After the original adsorbent completes desorption and regeneration in the regeneration zone 212, it rotates to the cooling zone 213 to cool the adsorbent. The fan-shaped cavity in the area corresponding to the cooling zone 213 in the holding cylinder 22 rotates to the adsorption zone 211, so that the adsorbent in the fan-shaped cavity replaces the adsorbent originally located in the adsorption zone 211 to continue to adsorb the deoxygenated hydrogen.

[0109] S3. According to the temperature deviation value in the regeneration zone 212, the flow rate of the regenerated hydrogen is adjusted through the flow control valve 51;

[0110] It is understood that if the flow rate of the regeneration hydrogen gas introduced into the regeneration zone 212 is too large, the adsorbent after the adsorption treatment in the regeneration zone 212 can be fully dried, but this will increase energy consumption and increase production costs. If the flow rate of the regeneration hydrogen gas is too small, the adsorbent after the adsorption treatment in the regeneration zone 212 cannot be fully dried. Therefore, in order to accurately control the flow rate of the regeneration hydrogen gas introduced into the regeneration zone 212, the flow rate of the regeneration hydrogen gas is adjusted according to the temperature deviation value in the regeneration zone 212, including:

[0111] S31, obtaining the temperature deviation value in the regeneration zone 212;

[0112] Among them, temperature deviation value = actual temperature value - preset temperature value;

[0113] The actual temperature value can be obtained by a temperature sensor provided in the regeneration zone 212 , and the preset temperature value can be obtained based on a database, historical data or experimental analysis.

[0114] S32, adjusting the flow rate of the regenerated hydrogen based on the temperature deviation value;

[0115] The regulating the flow rate of the regenerated hydrogen based on the temperature deviation value includes:

[0116] S321, generating regeneration hydrogen flow adjustment information based on the temperature deviation value and the first temperature deviation threshold;

[0117] The first temperature deviation threshold may be set based on a database, historical data, or experimental analysis.

[0118] In some embodiments, the first adjustment information of the regeneration hydrogen flow rate based on the temperature deviation value and the first temperature deviation threshold can be generated by comparing the temperature deviation value with the first temperature deviation threshold value, and generating the regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the first temperature deviation threshold value. For example, when the temperature deviation value exceeds the first temperature deviation threshold value, the regeneration hydrogen flow rate is increased to reduce the temperature deviation, so that the temperature deviation is stabilized within the first temperature deviation threshold value, and the adsorbent is fully dried while reducing energy consumption.

[0119] Generating regeneration hydrogen flow adjustment information based on the temperature deviation value and the first temperature deviation threshold includes:

[0120] S322, generating first regeneration hydrogen flow adjustment information based on the temperature deviation value and the second temperature deviation threshold;

[0121] The second temperature deviation threshold may also be set based on a database, historical data or experimental analysis;

[0122] The second regeneration hydrogen flow adjustment information is generated based on the temperature deviation value and the second temperature deviation threshold by comparing the temperature deviation value with the second temperature deviation threshold, and generating the first regeneration hydrogen flow adjustment information when the temperature deviation value exceeds the first temperature deviation threshold and is less than the second temperature deviation value.

[0123] The first regenerated hydrogen flow adjustment information includes:

[0124] The flow rate of the regenerated hydrogen is adjusted based on the temperature deviation value and the second temperature deviation threshold value, specifically in the following manner:

[0125]

[0126] in, is the regeneration hydrogen flow rate obtained at the current time point, is the regenerated hydrogen flow rate at the previous time point, is the temperature deviation value, is the set second temperature deviation threshold;

[0127] The reason for the above is that when the temperature deviation value exceeds the first temperature deviation threshold in a small range, by setting the first regeneration hydrogen flow adjustment information to maintain a stable flow, frequent adjustments can be reduced, energy consumption can be reduced, and the service life of the equipment can be extended.

[0128] S323, generating second regeneration hydrogen flow adjustment information based on the temperature deviation value and the third temperature deviation threshold;

[0129] In some embodiments, the second regeneration hydrogen flow adjustment information is generated based on the temperature deviation value and the third temperature deviation threshold by comparing the temperature deviation value with the third temperature deviation threshold, and the second regeneration hydrogen flow adjustment information is generated when the temperature deviation value exceeds the second temperature deviation threshold and is less than the third temperature deviation threshold.

[0130] The generating of the second regeneration hydrogen flow rate adjustment information includes:

[0131] The flow rate of regenerated hydrogen is adjusted based on the temperature deviation value. The specific method is as follows:

[0132] ;

[0133] in, is the flow rate of regenerated hydrogen; is the proportionality coefficient; is the integration coefficient, is the differential coefficient, is the sampling time.

[0134] In some embodiments, the integral coefficient The calculation method is:

[0135] ;

[0136] in, is the final integration coefficient, is the integral amplitude from 0 to time t, are the minimum integral coefficient and the maximum integral coefficient respectively.

[0137] By setting the minimum and maximum values ​​of the integral coefficient, the integral coefficient is limited to avoid distortion due to changes in the temperature deviation value, thereby preventing calculation errors in the process of adjusting the regenerated hydrogen flow.

[0138] In some embodiments, adjusting the flow rate of the regenerated hydrogen based on the temperature deviation value further includes:

[0139] S324, generating third regeneration hydrogen flow adjustment information based on the temperature deviation value and the third temperature deviation threshold;

[0140] The third temperature deviation threshold can be set based on a database, historical data or experimental analysis;

[0141] In some embodiments, the generating of the third regeneration hydrogen flow rate adjustment information based on the temperature deviation value and the third temperature deviation threshold value may be performed by comparing the temperature deviation value with the third temperature deviation threshold value, and generating the third regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the third temperature deviation threshold value;

[0142] The method for adjusting the regeneration hydrogen flow rate based on the temperature deviation value and the third temperature deviation threshold is:

[0143] ,

[0144] in, is the proportional term, is the integral term, is the differential term, They are the set minimum and maximum flow thresholds respectively;

[0145] When the temperature deviation value exceeds the third temperature deviation threshold, if the flow rate of the regenerated hydrogen is adjusted significantly, it may cause the regenerated hydrogen flow rate to be large, causing the regenerated hydrogen flow rate to exceed the safe range and cause system failure. By setting the minimum and maximum thresholds of the regeneration flow rate, the flow rate of the regenerated hydrogen is controlled to remain within the safe range, thereby improving the safety of the system during operation.

[0146] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An alkaline electrolytic cell adsorption method hydrogen purification system, characterized in that: include: A deoxygenation unit (1), an adsorption unit (2) connected to the deoxygenation unit, and a drying unit (3) connected to the adsorption unit (2); wherein the adsorption unit (2) comprises: a housing (21), the housing (21) being in communication with the deoxidation unit (1) and the drying unit (3), the housing (21) being a cylindrical structure with a cavity inside; A containing cylinder (22), the containing cylinder (22) being movably disposed in the outer shell (21) and adapted to fit the outer shell (21); A driver (23), the driver (23) being arranged on the housing (21), and an output end of the driver (23) being fixedly connected to the containing cylinder (22), for providing power to drive the containing cylinder (22) to rotate; The deoxygenation unit (1) comprises: A first heat exchanger (11), the first heat exchanger (11) is connected to the hydrogen outlet of the gas-liquid separation system of the alkaline electrolyzer, and the first heat exchanger (11) is used to perform heat exchange treatment on the raw hydrogen; a deoxidizer (12), the deoxidizer (12) being connected to the first heat exchanger (11), the deoxidizer (12) being filled with a catalyst for removing impurity oxygen in the raw hydrogen; a first heater (13), the first heater (13) being arranged on a pipeline between the first heat exchanger (11) and the deoxidizer (12), the first heater (13) being used to heat the raw hydrogen; a first cooler (14), the first cooler (14) being in communication with the first heat exchanger (11) and being used for cooling the deoxygenated hydrogen; a first gas-water separator (15), one end of the first gas-water separator (15) being connected to the first cooler (14), and the other end being connected to the adsorption unit (2), the first gas-water separator (15) being used to separate and remove condensed water from the deoxygenated hydrogen; The cavity in the shell (21) is provided with three groups of sealing elements that are arranged in an annular manner and fixed to the inner side of the shell (21), and the three sealing elements divide the shell (21) into an adsorption zone (211), a regeneration zone (212), and a cooling zone (213); A temperature sensor for monitoring temperature and transmitting signals is provided in the regeneration zone (212); The containing cylinder (22) is provided with a plurality of partitions adapted to the sealing element, and the plurality of partitions divide the containing cylinder (22) into a plurality of fan-shaped cavities of equal size, and the adsorbent is filled in each fan-shaped cavity; The rotation direction of the holding cylinder (22) is from the adsorption zone (211) to the regeneration zone (212), and then to the cooling zone (213).

2. The alkaline electrolytic cell adsorption hydrogen purification system according to claim 1, characterized in that: The housing (21) is also connected to a hydrogen main pipe (4), and the hydrogen main pipe (4) is adapted to the adsorption area (211). A pressure regulating valve (41) is provided on the hydrogen main pipe (4).

3. The alkaline electrolytic cell adsorption method hydrogen purification system according to claim 2, characterized in that: The drying unit (3) includes a hydrogen branch pipe (5), the hydrogen branch pipe (5) is connected to the hydrogen main pipe (4), and the regenerated hydrogen flows into the drying unit (3) through the hydrogen branch pipe (5); A flow regulating valve (51) is provided on the hydrogen branch pipe (5), and the flow regulating valve (51) is electrically connected to the temperature sensor.

4. The alkaline electrolytic cell adsorption hydrogen purification system according to claim 3, characterized in that: The drying unit (3) further comprises: A second heat exchanger (31), one end of the second heat exchanger (31) being connected to the hydrogen branch pipe (5), and the second heat exchanger (31) being used for performing primary heating and primary cooling on the regenerated hydrogen; a second heater (32), one end of the second heater (32) being connected to the second heat exchanger (31), and the other end being connected to the regeneration zone (212), the second heater (32) being used for secondary heating of the regenerated hydrogen; a second cooler (33), the second cooler (33) being in communication with the second heat exchanger (31) and being used for performing secondary cooling on the regenerated hydrogen; A second gas-water separator (34), one end of the second gas-water separator (34) is connected to the second cooler (33), and the other end is connected to the cooling zone (213), and is used to separate and remove condensed water in the regenerated hydrogen.

5. The alkaline electrolytic cell adsorption hydrogen purification system according to claim 1, characterized in that: The adsorbent filled in the containing cylinder (22) is divided into two layers of composite adsorbent, the upper layer adopts molecular sieve adsorbent and the lower layer adopts activated alumina adsorbent.

6. A control method for an alkaline electrolytic cell adsorption hydrogen purification system, characterized in that: An alkaline electrolytic cell adsorption hydrogen purification system according to any one of claims 1 to 5 is used, wherein the control method comprises: S1: introducing raw hydrogen, deoxidizing, dehydrating and adsorbing the raw hydrogen to obtain product hydrogen; S2: intermittently starting the driver (23) according to the saturation level of the adsorbent in the adsorption zone (211), driving the container (22) to rotate, and replacing the adsorbent in the adsorption zone (211); S3. According to the temperature deviation value in the regeneration zone (212), the flow rate of the regenerated hydrogen is adjusted through the flow regulating valve (51); S31, obtaining a temperature deviation value in the regeneration zone (212); Among them, temperature deviation value = actual temperature value - preset temperature value; S32, adjusting the flow rate of the regenerated hydrogen based on the temperature deviation value; The regulating the flow rate of the regenerated hydrogen based on the temperature deviation value includes: S321, generating regeneration hydrogen flow adjustment information based on the temperature deviation value and the first temperature deviation threshold; The first adjustment information of the regeneration hydrogen flow rate is generated based on the temperature deviation value and the first temperature deviation threshold by comparing the temperature deviation value with the first temperature deviation threshold, and generating the regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the first temperature deviation threshold; Generating regeneration hydrogen flow adjustment information based on the temperature deviation value and the first temperature deviation threshold includes: S322, generating first regeneration hydrogen flow adjustment information based on the temperature deviation value and the second temperature deviation threshold; The second regeneration hydrogen flow rate adjustment information is generated based on the temperature deviation value and the second temperature deviation threshold by comparing the temperature deviation value with the second temperature deviation threshold, and generating the first regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the first temperature deviation threshold and is less than the second temperature deviation value; The first regenerated hydrogen flow adjustment information includes: The flow rate of the regenerated hydrogen is adjusted based on the temperature deviation value and the second temperature deviation threshold value, specifically in the following manner: ； in, is the regeneration hydrogen flow rate obtained at the current time point, is the regenerated hydrogen flow rate at the previous time point, is the temperature deviation value, is the set second temperature deviation threshold; S323, generating second regeneration hydrogen flow adjustment information based on the temperature deviation value and the third temperature deviation threshold; The second regeneration hydrogen flow rate adjustment information is generated based on the temperature deviation value and the third temperature deviation threshold by comparing the temperature deviation value with the third temperature deviation threshold, and generating the second regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the second temperature deviation threshold and is less than the third temperature deviation threshold; The generating of the second regeneration hydrogen flow rate adjustment information includes: The flow rate of regenerated hydrogen is adjusted based on the temperature deviation value. The specific method is as follows: ； in, is the flow rate of regenerated hydrogen; is the proportionality coefficient; is the integration coefficient, is the differential coefficient, is the sampling time; The integration coefficient The calculation method is: ； in, is the final integration coefficient, is the integral amplitude from 0 to time t, are the minimum integral coefficient and the maximum integral coefficient respectively; The method of adjusting the flow rate of the regenerated hydrogen based on the temperature deviation value further includes: S324, generating third regeneration hydrogen flow adjustment information based on the temperature deviation value and the third temperature deviation threshold; The third regeneration hydrogen flow rate adjustment information is generated based on the temperature deviation value and the third temperature deviation threshold by comparing the temperature deviation value with the third temperature deviation threshold, and generating the third regeneration hydrogen flow rate adjustment information when the temperature deviation value exceeds the third temperature deviation threshold; The method for adjusting the regeneration hydrogen flow rate based on the temperature deviation value and the third temperature deviation threshold is: ； in, is the proportional term, is the integral term, is the differential term, , which are the set minimum and maximum flow thresholds respectively.

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