Integrated hydrogen production and charging system and method thereof

Abstract

The invention provides an integrated hydrogen production and charging system. The integrated hydrogen production and charging system comprises a hydrogen production machine, a compressor, a heat exchanger, a pressure swing adsorption device, a vacuum pump and a hydrogen charging machine. And integration of methanol water recombination low-pressure hydrogen production and hydrogen filling into the metal alloy hydrogen storage tank is realized. The invention also provides an integrated hydrogen production and charging method.

Description

Technical Field

[0001] The present invention relates to hydrogen production and hydrogen filling technologies, and particularly to an integrated hydrogen production and hydrogen filling system and method thereof. Background Art

[0002] Hydrogen energy is one of the new and vigorously developing energy sources today. Compared with new energy sources such as wind power generation and solar power generation, the advantage of hydrogen energy is that it is not restricted by the natural environment, so it can stably perform energy conversion and is currently one of the main fuel sources for fuel cells. In addition to being used as a fuel source for fuel cells, it can also be applied to the petroleum industry, the steel industry, or the food processing industry, etc. With the development of fuel cell technology, the hydrogen production devices or hydrogen supply devices for supplying hydrogen used in fuel cells have also been continuously innovated.

[0003] Currently, the main industrial method for hydrogen production is to obtain it by steam reforming of hydrocarbons (natural gas, methanol), and in some other chemical reactions, hydrogen can also be obtained as a by-product. In addition, there are many methods for producing hydrogen, such as electrolysis and thermolysis, etc. Currently, scientists are trying to find ways to produce hydrogen in large quantities and inexpensively to meet economic benefits.

[0004] Generally speaking, the hydrogen produced by a hydrogen production device needs to be stored in a pressurized or liquefied manner (for example: storing compressed hydrogen in a steel cylinder, or storing it in an alloy or carbon nanotube) to avoid leakage into the atmosphere. However, taking the storage method of compressed hydrogen as an example, if the stored hydrogen is to be supplied to a fuel cell, the pressurized stored hydrogen must be depressurized before it can be used again. In addition to increasing the time and cost consumed, the pressurization and depressurization steps also increase the safety risks in the hydrogen production process and the hydrogen supply process.

[0005] In recent years, hydrogen energy safety accidents have occurred globally one after another, posing huge challenges to the construction and operation safety of hydrogen refueling stations. Therefore, the safety technology thresholds and construction requirements for general high-pressure hydrogen refueling infrastructure have been continuously raised, discouraging some investors interested in hydrogen energy, which undoubtedly restricts the popularization of hydrogen energy and fuel cells. In addition, due to the extremely easy leakage of hydrogen during storage and transportation, the safety and economy of hydrogen storage and transportation are also issues that cannot be ignored.

[0006] Therefore, there are still many problems in the construction of the hydrogen supply industrial chain. Summary of the Invention

[0007] An embodiment of the present invention provides an integrated hydrogen production and filling system, comprising: a hydrogen generator, used to recombine methanol and water to produce hydrogen, and the produced hydrogen is purified for the first time through a palladium membrane purification device in the hydrogen generator; a compressor, used to pressurize the hydrogen from the hydrogen generator; a heat exchanger, connected to the compressor, used to cool the pressurized hydrogen; a pressure swing adsorption device, connected to the heat exchanger, used to purify the cooled hydrogen for a second time by adsorption; a vacuum pump, connected to the pressure swing adsorption device, used to reduce the pressure of the pressure swing adsorption device during desorption; and a hydrogen filling machine, used to fill the hydrogen from the pressure swing adsorption device into a metal alloy hydrogen storage tank.

[0008] In some embodiments, the integrated hydrogen production and charging system further includes a water chiller connected to the heat exchanger and the hydrogen charger, performing heat exchange with the heat exchanger and removing heat released by the hydrogen charger during hydrogen charging.

[0009] In some embodiments, the integrated hydrogen production and charging system further includes a temperature control unit connected to the pressure swing adsorption device to control the temperature of the pressure swing adsorption device during desorption to 150°C to 200°C and the temperature during adsorption to below 30°C.

[0010] In some embodiments, the temperature control unit introduces waste heat generated by the hydrogen generator to increase the temperature of the pressure swing adsorption device.

[0011] In some embodiments, the temperature control unit introduces ice water from a water chiller to cool the pressure swing adsorption device.

[0012] In some embodiments, the integrated hydrogen production and charging system further includes: a first buffer tank, disposed between the hydrogen generator and the compressor, for temporarily storing the hydrogen that has undergone the first purification; a second buffer tank, disposed between the pressure swing adsorption device and the hydrogen charging machine, for temporarily storing the hydrogen that has undergone the second purification.

[0013] In some embodiments, the integrated hydrogen production and charging system further includes a backflow channel to flow the hydrogen from the heat exchanger back to the first buffer tank.

[0014] In some embodiments, the pressure swing adsorption apparatus is a multi-tower pressure swing adsorption apparatus.

[0015] An embodiment of the present invention also provides an integrated hydrogen production and charging method, which includes, in sequence: a hydrogen production step, in which methanol and water undergo a recombination reaction to produce hydrogen; a first purification step, in which the hydrogen produced in the hydrogen production step is purified by a palladium membrane purification device; a pressurization step, in which the hydrogen that has passed through the first purification step is pressurized; a cooling step, in which the hydrogen that has passed through the pressurization step is cooled; a second purification step, in which the hydrogen that has passed through the cooling step is purified by a pressure swing adsorption device; and a hydrogen charging step, in which the hydrogen that has passed through the second purification step is filled into a metal alloy hydrogen storage tank.

[0016] In some embodiments, the hydrogen gas after the first purification step contains 500 - 700 ppm of water vapor and 200 - 300 ppm of methane, and the hydrogen gas after the second purification step contains less than 5 ppm of water vapor and less than 50 ppm of methane.

[0017] In some embodiments, the second purification step is carried out by a multi - tower pressure swing adsorption device, in which a plurality of adsorption towers of the multi - tower pressure swing adsorption device simultaneously and alternately carry out different steps of the regeneration cycle process of adsorbing and desorbing impurities, and this cycle process sequentially includes at least: an adsorption step of adsorbing the hydrogen gas that has passed through the cooling step until the first adsorption tower is nearly saturated; a depressurize&equalization step of equalizing the pressure between the first adsorption tower and the second adsorption tower that is carrying out the cooling and pressurization equalization step; a heating&blowdown step of discharging impurities from the first adsorption tower; a heating&purge step of purging the impurities discharged from the first adsorption tower; a heating&vacuum step of releasing the residual impurities in the first adsorption tower; a cooling&re - pressurizeequalization step of equalizing the pressure between the first adsorption tower and the third adsorption tower that is carrying out the depressurize&equalization step; a pressurization step of increasing the pressure of the first adsorption tower to the adsorption pressure; and an idle step of putting the first adsorption tower in an idle state.

[0018] In some embodiments, the pressure of the hydrogen gas after the first purification step is 7 - 14 psig, and the pressure of the hydrogen gas after the second purification step is 145 - 200 psig.

[0019] In some embodiments, the hydrogen gas is compressed to 160 - 215 psig during the pressurization step.

[0020] In some embodiments, the pressure during the desorption period of the second purification step is less than 7 psia.

[0021] In some embodiments, the temperature during the desorption period of the second purification step is 150°C - 200°C, and the temperature during the adsorption period is below 30°C.

[0022] In some embodiments, the methanol - water concentration used in the hydrogen production step is 62% ± 5 wt.%.

[0023] In some embodiments, the hydrogen filling step fills 10 hydrogen storage tanks of 1.0 liter (hydrogen storage 45 g / tank) within 2 hours. Description of the Drawings

[0024] Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, in accordance with standard practice in the art, the various features are not drawn to scale and are merely for illustrative purposes. In fact, the dimensions of the components may be arbitrarily enlarged or reduced to clearly show the features of the embodiments of the present invention.

[0025] Figure 1 FIG. is a schematic diagram of an integrated hydrogen production and hydrogen filling system according to some embodiments of the present case.

[0026] Figure 2 FIG. is a flowchart of an integrated hydrogen production and hydrogen filling method according to some embodiments of the present case.

[0027] Figure 3 FIG. is a flowchart of a second purification step in an integrated hydrogen production and hydrogen filling method according to some embodiments of the present case.

[0028] Reference numerals

[0029] 10 Hydrogen generator

[0030] 11 Fuel tank

[0031] 12 Reactor

[0032] 13 Palladium membrane purification device

[0033] 20 First buffer tank

[0034] 30 Compressor

[0035] 40 Heat exchanger

[0036] 50 Ice water machine

[0037] 60 Backflow pipe

[0038] 70 Pressure swing adsorption device

[0039] 71 First adsorption tower

[0040] 72 Second adsorption tower

[0041] 73 Third adsorption tower

[0042] 80 Vacuum pump

[0043] 90 Temperature control unit

[0044] 100 Second buffer tank

[0045] 110 Hydrogen filling machine

[0046] 120 Metal alloy hydrogen storage tank

[0047] 500 Method

[0048] 510 Hydrogen production step

[0049] 520 First purification step

[0050] 530 Pressurization step

[0051] 540 Cooling step

[0052] 550 Second purification step

[0053] 551 Adsorption step

[0054] 552 Pressure reduction and equilibrium step

[0055] 553 Desorption step

[0056] 553-1 Heating and discharging step

[0057] 553-2 Heating and purging step

[0058] 553-3 Heating and purging step

[0059] 554 Cooling, pressurization and equilibrium step

[0060] 555 Pressure increasing step

[0061] 556 Standby step

[0062] 560 Hydrogen filling step

[0063] 1000 Integrated hydrogen production and filling system Specific implementation manner

[0064] The following disclosure provides many different embodiments or examples to demonstrate different components of the embodiments of the present invention. The following will disclose specific examples of each component and its arrangement in this specification to simplify the description of this disclosure. Of course, these specific examples are not used to limit this disclosure.

[0065] Here, the terms "about", "approximately", and "substantially" generally mean within 20% of a given value or range, preferably within 10%, more preferably within 5%, or 3%, or 2%, or 1%, or 0.5%. It should be noted that the quantities provided in the specification are approximate quantities, that is, the meanings of "about", "approximately", and "substantially" may still be implied even without specific mention of "about", "approximately", or "substantially". The terms "comprising", "including", "having", and their variants all mean "including but not limited to", unless otherwise specifically emphasized in other ways. The term "connected" includes direct connection and indirect connection. For example, when it is mentioned in a description that a first device is connected to a second device, it may include embodiments where the first and second devices are directly connected, and may also include embodiments where there are additional devices between the first and second devices such that they are indirectly connected. Unless otherwise stated, "first" and "second" are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features.

[0066] To further promote the application of hydrogen energy, the present invention provides an integrated low-pressure hydrogen production and hydrogen filling system, which produces hydrogen through methanol-water reforming and fills hydrogen into a metal alloy hydrogen storage tank. The hydrogen storage alloy in the metal alloy hydrogen storage tank undergoes a reversible reaction with hydrogen at a certain temperature and pressure to form a metal solid solution and a metal hydride. When this reversible reaction undergoes a hydrogen absorption reaction, heat is released, and hydrogen is released when heat is absorbed. Since the metal alloy hydrogen storage tank belongs to low-pressure hydrogen storage, the tank pressure is, for example, lower than 300 psig at 35°C. Even if the tank ruptures, it will not cause an explosion, and it can self-limit the gas release rate. Compared with high-pressure hydrogen storage with a pressure of, for example, about 5000 - 10000 psig, it has high safety, high cost-effectiveness of infrastructure, and is relatively easy to quickly popularize.

[0067] The architecture of the integrated hydrogen production and hydrogen filling system will be further described in detail below according to some embodiments.

[0068] Referring to Figure 1 , which shows a schematic diagram of the integrated hydrogen production and hydrogen filling system according to some embodiments of this case. As shown in the figure, the integrated hydrogen production and hydrogen filling system 1000 mainly includes, in sequence: a hydrogen generator 10, a compressor 30, a heat exchanger 40, a pressure swing adsorption device 70, a vacuum pump 80, and a hydrogen filling machine 110.

[0069] According to some embodiments, the hydrogen generator 10 includes a fuel tank 11, a reactor 12, a palladium membrane purification device 13, etc. The hydrogen generator 10 uses methanol water stored in the fuel tank 11, performs a methanol reforming reaction in the reactor 12 to generate hydrogen, and the generated hydrogen is purified for the first time by the palladium membrane purification device 13. The present invention uses methanol water reforming to produce hydrogen, with mature technology, stable hydrogen production, compact equipment, rapid startup, and lower operating costs compared to other hydrogen production methods. In addition, methanol water can be stored or transported in liquid form usually, and hydrogen can be produced in real time according to the hydrogen demand for use.

[0070] In some embodiments, the hydrogen-rich gas produced by the reactor 12 is unpurified hydrogen, and its hydrogen concentration is between about 60% and about 72%. In some embodiments, the reactor 12 can perform steam reforming with a suitable catalyst at a suitable reaction temperature (for example, between 270°C and 450°C). Under the action of the steam reforming catalyst, the methanol water fuel undergoes a methanol cracking reaction and a water gas shift reaction, and the reaction equations are: (1) Methanol cracking reaction: CH3OH → CO + 2H2; (2) Water gas shift reaction: CO + H2O → CO2 + H2; (3) Actual steam reforming: CH3OH + H2O → xCO2 + yCO + zCH4 + mH2 + nH2O. The gas produced after the methanol steam undergoes the methanol reforming reaction is hydrogen-rich gas, in which the hydrogen content is only about 60 - 70%, and it also contains CO, CO2, CH4, and some water vapor. In some embodiments, the mechanism for the reactor 12 to produce hydrogen can be the autothermal steam reforming (ATR).

[0071] In some implementations, the palladium membrane purification device 13 is a flat purification module, which is characterized in that the material is not the traditional cylindrical porous ceramic surface coating process, but is composed by using a thin film stacking method. The palladium membrane purification device 13 can purify the hydrogen-rich gas produced by the hydrogen generator 10, remove carbon dioxide, carbon monoxide, methane, or unreacted methanol precursors generated by the steam reforming reaction, and make it into high-purity hydrogen. In some embodiments, the purity of the hydrogen purified by the palladium membrane purification device 13 can reach more than 99.95%. In some embodiments, the palladium membrane purification device 13 is a palladium alloy module stacked by palladium alloy thin films. In some embodiments, the palladium membrane purification device 13 is a palladium alloy module stacked by a palladium alloy thin film of 60% by weight of palladium and 40% by weight of copper.

[0072] However, the hydrogen storage alloy for storing hydrogen is highly sensitive to impurity gases, and the stored hydrogen needs to meet the conditions such as purity > 99.99%, water content < 5 ppmv, carbon monoxide < 1 ppmv, carbon dioxide < 3 ppmv, methane < 10 ppmv, etc. Methane generated by CO methanation will seriously affect the performance of the hydrogen storage alloy. In addition, the hydrogen generated by methanol-water reforming will cause a decrease in hydrogen pressure after purification steps such as passing through a palladium membrane and cannot be directly charged into the metal hydrogen storage alloy tank. Therefore, the present invention will further pressurize and purify the hydrogen, which will be described in detail below.

[0073] The compressor 30 boosts the pressure of the hydrogen from the hydrogen generator 10. According to some embodiments, the compressor 30 is a diaphragm compressor. The heat exchanger 40 is connected to the compressor 30 to cool the hydrogen after pressure boosting. Before entering the adsorption device 70, the temperature of the hydrogen compressed by the compressor 30 may rise to above 300 °C and water will condense. Through the heat exchanger 40, the gas temperature can be reduced to about 30 °C, and at the same time, the condensed water is removed, avoiding affecting the water removal efficiency of the pressure swing adsorption device 70 after the hydrogen enters the pressure swing adsorption device 70, and at the same time avoiding the influence of the temperature rise of the compressed hydrogen on the adsorption efficiency of the pressure swing adsorption device 70.

[0074] The pressure swing adsorption device 70 is connected to the heat exchanger 40 to perform a second purification of the cooled hydrogen by an adsorption method. The pressure swing adsorption (PSA) method is a gas purification method that mainly uses the different adsorption forces of adsorbents for different substances to achieve the effect of removing impurities. Under high pressure, the impurities in the gas to be purified are adsorbed on the adsorbent, so that the mixed gas can be separated. Then, by "changing the pressure" of the adsorbent, the desorption of the impurities is realized, and the adsorbent is regenerated, so as to carry out the next round of adsorption process. Since the adsorption and desorption processes are realized by pressure change, this method is called the pressure swing adsorption method. In some embodiments, the adsorbents used in the pressure swing adsorption device 70 include activated carbon, alumina and / or zeolite molecular sieve / or hollow fiber, etc. In some embodiments, the pressure swing adsorption device 70 is a multi-tower pressure swing adsorption device. For example, a two-tower pressure swing adsorption device, a three-tower pressure swing adsorption device, a four-pressure swing adsorption device, etc. In Figure 1In the illustrated embodiment, the pressure swing adsorption device 70 is described by taking a three-tower pressure swing adsorption device as an example. The hydrogen gas after cooling can be selectively introduced into the first adsorption tower 71, the second adsorption tower 72, and / or the third adsorption tower 73 through the regulation of a gas valve (not shown) in the pressure swing adsorption device 70. During the purification process, the pressure can be balanced among the first adsorption tower 71, the second adsorption tower 72, and the third adsorption tower 73, and the purified hydrogen gas can enter the subsequent device from each adsorption tower. In other embodiments, the adsorption towers of the pressure swing adsorption device 70 are multi-bed adsorption towers, such as three-bed adsorption towers, four-bed adsorption towers, etc.

[0075] A vacuum pump 80 is connected to the pressure swing adsorption device 70 to reduce the pressure of the pressure swing adsorption device 70 during desorption. Generally speaking, under the adsorption equilibrium condition, when any adsorbent adsorbs the same gas, the higher the gas pressure and the lower the temperature, the greater the adsorption capacity of the adsorbent; conversely, the lower the pressure and the higher the temperature, the smaller the adsorption capacity. Usually, the pressure swing adsorption device adsorbs at high pressure and normal temperature and desorbs at normal pressure and high temperature. Since CH4 has a strong adsorption capacity, its desorption in the adsorbent cycle usually needs to be carried out under vacuum and high temperature conditions. Therefore, in this case, by adding a vacuum pump 80, the adsorption device 70 can adsorb at high pressure and desorb under vacuum, which can reduce the amount of waste hydrogen while strengthening the desorption of the adsorption device 70. When the pressure of the adsorption tower is reduced, the adsorbed CH4 desorbs from the adsorbent and is discharged from the inlet end of the adsorption tower.

[0076] According to some embodiments, a hydrogen filling machine 110 fills hydrogen gas from the pressure swing adsorption device 70 into one or more metal alloy hydrogen storage tanks 120, that is, the hydrogen filling machine 110 can fill one or more metal alloy hydrogen storage tanks 120 at the same time. The hydrogen gas after passing through the adsorption device 70 can still maintain a certain pressure (for example, 145 - 200 psig), enabling the hydrogen filling machine 110 to directly fill the hydrogen gas after passing through the adsorption device 70 into the metal alloy hydrogen storage tank 120. In some embodiments, the materials of the metal alloy hydrogen storage tank 120 include LaNi5, TiMn2, TiFe, LaNi3, Mg2Ni, BCC (body-centered cubic)-TiV, and Mg, etc. In some embodiments, the volume of the metal alloy hydrogen storage tank 120 is 0.1 - 5 L, such as 0.5 - 3 L, 1 - 2 L, etc.

[0077] According to some embodiments, the integrated hydrogen production and hydrogen filling system 1000 further includes an ice water machine 50, which is connected to the heat exchanger 40 and the hydrogen filling machine 110, can perform heat exchange with the heat exchanger 40, and can simultaneously reduce the temperature of the adsorption device 70 and remove the heat released during the hydrogen filling of the hydrogen filling equipment 110 to ensure that the metal alloy hydrogen storage tank 120 can be continuously filled with hydrogen.

[0078] According to some embodiments, the integrated hydrogen production and hydrogen filling system 1000 further includes a temperature control unit 90, which is connected to the pressure swing adsorption device 70 and controls the temperature of the pressure swing adsorption device 70 during desorption to be 150°C to 200°C (such as 155°C to 195°C, 165°C to 185°C, etc.), and the temperature during adsorption to be below 30°C (such as 15°C to 28°C, 20°C to 25°C). In some embodiments, the waste heat generated by the hydrogen generator 10 can be used to heat the pressure swing adsorption device 70 through the temperature control unit 90. In some embodiments, when the pressure swing adsorption device 70 needs to be cooled down, cold water from the ice water machine 50 can also be introduced by the temperature control unit 90 for cooling.

[0079] In some embodiments, between the hydrogen generator 10 and the compressor 30 of the integrated hydrogen production and hydrogen filling system 1000, there is also a first buffer tank 20 for temporarily storing the hydrogen purified for the first time. The first buffer tank 20 can play a buffering role, thereby reducing the system pressure fluctuation. In some embodiments, between the pressure swing adsorption device 70 and the hydrogen filling machine 1100 of the integrated hydrogen production and hydrogen filling system 1000, there is also a second buffer tank 100 for temporarily storing the hydrogen purified for the second time. The second buffer tank 100 plays a role in stabilizing the pressure when the adsorption towers work alternately, ensuring a stable continuous supply of hydrogen.

[0080] In some embodiments, the integrated hydrogen production and hydrogen filling system 1000 further includes a reverse flow channel 60 that spills back the hydrogen from the heat exchanger 40 to the first buffer tank 20. The pressure of the compressed hydrogen entering the pressure swing adsorption device 70 is controlled to avoid large fluctuations in the hydrogen flow rate. By adding a reverse flow channel 60 after the heat exchanger 40, the excess overpressure gas can be spilled back to the first buffer tank 20, playing an anti-surge role to ensure that the hydrogen can be stably input into the pressure swing adsorption device 70 for moisture and methane removal to achieve the required hydrogen quality target and avoid the influence of pressure changes on the performance of the pressure swing adsorption device 70.

[0081] The following will, according to some embodiments, with reference to Figure 1 、 Figure 2 Further, the integrated hydrogen production and hydrogen filling method 500 using the integrated hydrogen production and hydrogen filling system 1000 will be described in detail. It should be noted that the integrated hydrogen production and hydrogen filling method 500 can also use other systems / devices other than the integrated hydrogen production and hydrogen filling system 1000. Using the integrated hydrogen production and hydrogen filling method 500 of the integrated hydrogen production and hydrogen filling system 1000 as an example is only for convenience of description and is not intended to limit the embodiments of the present invention.

[0082] As Figure 2As shown, the integrated hydrogen production and hydrogen filling method 500 sequentially includes: a hydrogen production step 510, a first purification step 520, a pressurization step 530, a cooling step 540, a second purification step 550, and a hydrogen filling step 560.

[0083] In some embodiments, the hydrogen production step 510 causes the methanol water to undergo a reforming reaction to produce hydrogen. For example, the methanol water in the fuel tank 11 enters the reactor 12 for the reforming reaction, and the concentration of the methanol water used is, for example, 62% ± 5 wt.%. In some embodiments, the mechanism for the hydrogen production machine 10 to produce hydrogen can be the steam reforming (SR) method. The hydrogen production step 510 can perform steam reforming with a suitable catalyst at a suitable reaction temperature (for example, between 270°C and 450°C). The hydrogen-rich gas produced by the hydrogen production step 510 of the hydrogen production machine 10 is unpurified hydrogen, and its hydrogen concentration is between about 60% and about 72%, and still contains CO, CO2, CH4, and some water vapor.

[0084] In some embodiments, the first purification step 520 purifies the hydrogen produced by the hydrogen production step 510 through the palladium membrane purification device 13. In some embodiments, through the palladium membrane purification device 13 in the hydrogen production machine 10, the hydrogen produced by the hydrogen production step 510 is purified, and CO is methanated. Methanation of CO is a method that can effectively remove CO in the syngas, but precise control of the reaction temperature is quite important. If the temperature is too high, CO2 will also be methanated, consuming the H2 in the syngas. In some embodiments, the hydrogen purity after the first purification step 520 > 99.95%, the moisture content < 750 ppmv (such as 600 - 650 ppmv, 500 - 700 ppmv, etc.), carbon monoxide < 1 ppmv (such as 0.1 - 0.5 ppmv, etc.), carbon dioxide < 3 ppmv (such as 1 - 2 ppmv, etc.), methane < 350 ppmv (such as 200 - 300 ppmv, 100 - 250 ppmv, etc.). In some embodiments, the hydrogen pressure after the first purification step 520 is 7 - 14 psig (such as 8 - 12 psig, 9 - 10 psig, etc.). The hydrogen after removing CO can be directly used in the fuel cell without poisoning the fuel cell electrodes. However, the metal alloy hydrogen storage tank is highly sensitive to impurity gases, and it is still necessary to further remove CH4 and moisture contained in the gas after CO methanation.

[0085] In some embodiments, the pressurization step 530 pressurizes the hydrogen gas that has undergone the first purification step 520. In some embodiments, a compressor 30 is used to pressurize the hydrogen gas purified by the palladium membrane purification device 13 in the hydrogen generator 10, and compress it to 160 - 215 psig (for example, 175 - 200 psig, 180 - 190 psig, etc.). In some embodiments, the cooling step 540 cools the hydrogen gas that has undergone the pressurization step 530. In some embodiments, a heat exchanger 40 is used to cool the hydrogen gas from the compressor 30 to below 30°C (for example, 15°C - 28°C, 20°C - 25°C), while removing the condensed water to reduce the load on the subsequent pressure swing adsorption device 70.

[0086] In some embodiments, the second purification step 550 purifies the hydrogen gas that has undergone the cooling step 540 through the pressure swing adsorption device 70. Then refer to Figure 3 , in some embodiments, the second purification step 550 is carried out by a multi-column pressure swing adsorption device, in which different steps of the regeneration cycle process of adsorbing and desorbing impurities are simultaneously and alternately carried out in a plurality of adsorption columns of the multi-column pressure swing adsorption device, and the cycle process sequentially includes at least: an adsorption step 551, a depressurize&equalization step 552, a heating&blowdown step 553-1, a heating&purge step 553-2, a heating&vacuum step 553-3, a cooling&re-pressurize equalization step 554, a pressurization step 555, and an idle step 556. Among them, the heating&blowdown step 553-1, the heating&purge step 553-2, and the heating&vacuum step 553-3 are collectively referred to as the desorption step 553. In some embodiments, the hydrogen gas passes through the multi-column pressure swing adsorption device 70, where one column adsorbs the water vapor to below 5 ppmv (for example, below 3 ppmv, below 1 ppmv), removes the methane to below 50 ppmv (for example, below 30 ppmv, below 10 ppmv), and at the same time the other columns are regenerated, and then the columns are alternated to achieve continuous adsorption and desorption operations.

[0087] Refer to simultaneously Figure 1 , Figure 3, in some embodiments, the first adsorption tower 71 first performs the adsorption step 551 to adsorb the hydrogen gas that has undergone the cooling step 540 until the first adsorption tower 71 is nearly saturated. In some embodiments, the temperature during adsorption is below 30°C (for example, 15°C to 28°C, 20°C to 25°C). The first adsorption tower 71 then performs the pressure reduction and equilibrium step 552 to equalize the pressure between the first adsorption tower 71 and the second adsorption tower 72 that is performing the cooling, pressurization, and equilibrium step.

[0088] In some embodiments, the first adsorption tower 71 then performs the desorption step 553. In some embodiments, the temperature during desorption in the second purification step 550 is 150°C to 200°C (for example, 160 to 190°C, 170 to 180°C). The temperature increase and discharge step 553-1 discharges impurities from the first adsorption tower 71. When the temperature rises, the adsorption force of the adsorbent decreases, enabling the impurities originally adsorbed on the adsorbent to be desorbed. In the subsequent temperature increase and purge step 553-2, by introducing a purge gas into the adsorption tower, the impurities discharged from the first adsorption tower 71 are purged, and the impurities desorbed from the adsorbent are blown out of the adsorption tower. Then, the temperature increase and vacuum pumping step 553-3 is performed. Using a vacuum pump 80, the pressure in the first adsorption tower 71 is made less than 7 psia (for example, less than 3 psia, less than 1 psia, etc.), further reducing the adsorption force of the adsorbent, releasing the residual impurities in the first adsorption tower 71, and pumping out the impurities desorbed due to the pressure drop.

[0089] In some embodiments, the first adsorption tower 71 then performs the cooling, pressurization, and equilibrium step 554 to equalize the pressure between the first adsorption tower 71 and the third adsorption tower 73 that is performing the pressure reduction and equilibrium step. Then, the pressure increase step 555 is performed to increase the pressure of the first adsorption tower 71 to the adsorption pressure. Finally, the standby step 556 is entered, and the first adsorption tower 71 is placed in a standby state, waiting for the next cycle step.

[0090] It should be noted that other adsorption towers will also perform the same cycle process simultaneously. However, at the same time point, different adsorption towers will perform different steps, which will not be elaborated here.

[0091] The purity of H2 in the purified hydrogen gas is >99.99%, the moisture content is <5 ppmv, carbon monoxide is <1 ppmv, carbon dioxide is <3 ppmv, methane is <10 ppmv, and the pressure can be maintained at 145 to 200 psig. The quality of the hydrogen gas can meet the requirements of ISO14687 and the hydrogen storage alloy.

[0092] In some embodiments, the hydrogen filling step 560 fills the hydrogen gas that has undergone the second purification step 550 into one or more metal alloy hydrogen storage tanks 120. In some embodiments, the hydrogen filling step 560 fills, for example, 10 1.0-liter hydrogen storage tanks (hydrogen storage 45 g / tank) within 2 hours for use by a hydrogen energy vehicle.

[0093] It should be noted that additional steps can be provided before, during, and after the method 500. For example, a first buffering step can be included between the first purification step 520 and the pressurization step 530, and a second buffering step can be included between the second purification step 550 and the hydrogen charging step 560.

[0094] The integrated hydrogen production and hydrogen charging system of the present invention can produce hydrogen at low pressure by methanol-water reforming, and use a compressor to pressurize it, so that the hydrogen can still maintain 145 - 200 psig after being purified by a pressure swing adsorption device, and can be smoothly filled into a metal alloy hydrogen storage tank through a hydrogen charger, quickly completing the filling of the metal alloy hydrogen storage tank or realizing the concept of hydrogen tank exchange. The integrated hydrogen production and hydrogen charging system of the present invention can also be used for the construction of low-pressure hydrogen refueling stations. Generally, the pressure of a high-pressure hydrogen storage station generally reaches above 5000 psig, and the requirements for safety are relatively high. Therefore, it is difficult to reduce the construction cost and speed. However, through the integrated hydrogen production and hydrogen charging system of the present invention, methanol-water can be stored or transported in a liquid state, and hydrogen can be produced in real time according to the demand for hydrogen. In addition, since the system stores hydrogen in a low-pressure metal alloy tank, the safety is relatively high, and the construction of regional low-pressure hydrogen refueling stations can be accelerated at low cost, realizing the popularization of hydrogen energy.

[0095] Through the invention of this case, the concept of hydrogen tank exchange can also be realized. For example, a hydrogen storage tank is filled at a hydrogen production plant, and the hydrogen storage tank is delivered to an exchange station (which can be, for example, a gas station, a convenience store, etc.) through a logistics center and stocked. The empty tank used by the consumer can be directly exchanged for a new tank filled with hydrogen, greatly improving the convenience of hydrogen refueling, thereby accelerating the popularization of the use of hydrogen.

[0096] The components of several embodiments are outlined above so that those skilled in the art can more easily understand the viewpoints of the embodiments of the present invention. Those skilled in the art should understand that they can design or modify other processes and structures based on the embodiments of the present invention to achieve the same purposes and / or advantages as the embodiments introduced herein. Those skilled in the art should also understand that such equivalent processes and structures do not depart from the spirit and scope of the present invention, and they can make various changes, substitutions, and replacements without departing from the spirit and scope of the present invention.

Claims

1. An integrated hydrogen production and hydrogen filling system, characterized in that, Including: A hydrogen generator for reforming methanol water to produce hydrogen and purifying the produced hydrogen for the first time through a palladium membrane purification device in the hydrogen generator; A compressor for boosting the pressure of the hydrogen from the hydrogen generator; A heat exchanger connected to the compressor for cooling the hydrogen after pressure boosting; A pressure swing adsorption device connected to the heat exchanger for purifying the hydrogen after cooling by adsorption for the second time; A vacuum pump connected to the pressure swing adsorption device for depressurizing the pressure swing adsorption device during desorption; and A hydrogen filling machine for filling the hydrogen from the pressure swing adsorption device into one or more metal alloy hydrogen storage tanks.

2. The integrated hydrogen production and hydrogen filling system according to claim 1, characterized in that, It further includes an ice water machine connected to the heat exchanger and the hydrogen filling machine, performing heat exchange with the heat exchanger and removing the heat released during hydrogen filling by the hydrogen filling machine.

3. The integrated hydrogen production and hydrogen filling system according to claim 2, characterized in that, It further includes a temperature control unit connected to the pressure swing adsorption device for controlling the temperature of the pressure swing adsorption device during desorption to be 150°C to 200°C and the temperature during adsorption to be below 30°C.

4. The integrated hydrogen production and hydrogen filling system according to claim 3, wherein The temperature control unit introduces the waste heat generated by the hydrogen generator for heating up the pressure swing adsorption device.

5. The integrated hydrogen production and hydrogen filling system according to claim 3, characterized in that, The temperature control unit introduces the ice water of the ice water machine for cooling down the pressure swing adsorption device.

6. The integrated hydrogen production and hydrogen filling system according to claim 1, wherein It further includes: A first buffer tank arranged between the hydrogen generator and the compressor for temporarily storing the hydrogen purified for the first time; A second buffer tank arranged between the pressure swing adsorption device and the hydrogen filling machine for temporarily storing the hydrogen purified for the second time.

7. The integrated hydrogen production and charging system according to claim 6, characterized in that: It further includes a reverse flow channel for reversing the flow of the hydrogen from the heat exchanger to the first buffer tank.

8. The integrated hydrogen production and hydrogen filling system according to claim 1, characterized in that, The pressure swing adsorption device is a multi-tower pressure swing adsorption device.

9. An integrated hydrogen production and hydrogen filling method, characterized in that, Sequentially including: A hydrogen production step of reforming methanol water to produce hydrogen; A first purification step of purifying the hydrogen produced in the hydrogen production step through a palladium membrane purification device; A pressurization step of pressurizing the hydrogen after the first purification step; A cooling step of cooling the hydrogen after the pressurization step; A second purification step of purifying the hydrogen after the cooling step through a pressure swing adsorption device; and A hydrogen filling step of filling the hydrogen after the second purification step into one or more metal alloy hydrogen storage tanks.

10. The integrated hydrogen production and hydrogen filling method according to claim 9, characterized in that, The hydrogen after the first purification step contains 500 - 700 ppmv of water vapor and 200 - 300 ppmv of methane, and the hydrogen after the second purification step contains below 5 ppmv of water vapor and below 50 ppmv of methane.

11. The integrated hydrogen production and hydrogen filling method according to claim 9, characterized in that, The second purification step is carried out through a multi-tower pressure swing adsorption device, where different steps of the regeneration cycle process of simultaneously and alternately adsorbing and desorbing impurities are carried out in multiple adsorption towers of the multi-tower pressure swing adsorption device, and the cycle process sequentially includes at least: An adsorption step of adsorbing the hydrogen after the cooling step until the first adsorption tower is nearly saturated; A pressure reduction and balance step of balancing the pressure between the first adsorption tower and the second adsorption tower undergoing a cooling and pressurization balance step; A heating and discharging step of discharging impurities from the first adsorption tower; Heating and purging step to purge impurities discharged from the first adsorption tower; Heating and vacuum pumping step to release residual impurities in the first adsorption tower; The temperature reduction and pressure equalization step to equalize the pressure between the first adsorption tower and the third adsorption tower performing the pressure reduction and equalization step; Pressure boosting step to increase the pressure of the first adsorption tower to the adsorption pressure; And Standby step to put the first adsorption tower in a standby state.

12. The integrated hydrogen production and charging method according to claim 10, characterized in that: The hydrogen pressure after the first purification step is 7 - 14 psig, and the hydrogen pressure after the second purification step is 145 - 200 psig.

13. The integrated hydrogen production and hydrogen filling method according to claim 12, characterized in that, Hydrogen is compressed to 160 - 215 psig in the pressurization step.

14. The integrated hydrogen production and hydrogen filling method according to claim 10, characterized in that, The pressure during desorption in the second purification step is less than 7 psia.

15. The integrated hydrogen production and hydrogen filling method according to claim 10, characterized in that, The temperature during desorption in the second purification step is 150°C - 200°C, and the temperature during adsorption is below 30°C.

16. The integrated hydrogen production and hydrogen filling method according to claim 10, characterized in that The methanol - water concentration used in the hydrogen production step is 62% ± 5 wt.%.

17. The integrated hydrogen production and hydrogen filling method according to claim 10, wherein, The hydrogen filling step fills 10 hydrogen storage tanks of 1.0 liter (hydrogen storage 45 g / tank) within 2 hours.

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