Ammonia decomposition hydrogen production system and method based on double adsorption

Abstract

The application discloses a kind of ammonia decomposition hydrogen production system and hydrogen production method based on double adsorption, the liquid outlet of ammonia storage device in the system is communicated with the gas inlet of ammonia decomposition reaction device through the cold liquid channel on heat exchange device, the gas outlet of ammonia decomposition reaction device passes through the gas channel on heat exchange device, and is communicated with first adsorption device by the aid of first compression device, the adsorption outlet of first adsorption device is communicated with the gas inlet of second adsorption device, and part of the gas after being adsorbed by second adsorption device is introduced into terminal equipment application, and part of it is introduced into first adsorption device to be used for purging first adsorption device.The system realizes the recycling of tail gas after desorption of adsorption column, realizes zero emission of ammonia and nitrogen oxides, and improves the purging effect of adsorption device.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of clean energy equipment, in particular to an ammonia decomposition hydrogen production system based on double adsorption and a hydrogen production method. BACKGROUND

[0002] Hydrogen is a green clean energy with abundant sources, and has the characteristics of large energy density, high calorific value, abundant reserves, wide sources, high conversion efficiency, etc., and generates water after combustion without carbon emissions. However, hydrogen transportation and storage are key problems restricting the popularization and application of hydrogen energy technology; ammonia is a carbon-free hydrogen-rich carrier, and ammonia hydrogen storage has unique advantages such as high energy density, easy storage and transportation, high safety, mature industrial foundation, and carbon-free terminal emissions; ammonia can be used as a hydrogen storage carrier to produce hydrogen and nitrogen mixed gas or high-purity hydrogen on site through ammonia decomposition reaction at the energy terminal; ammonia decomposition hydrogen production is a key reaction process in the "ammonia-hydrogen" energy technology route, in which ammonia is decomposed by thermal catalysis to generate hydrogen and nitrogen with a volume fraction of 3:1. Due to the limitation of thermodynamic equilibrium, there is still a small amount of un-decomposed ammonia in the hydrogen and nitrogen mixed gas after ammonia decomposition, which usually needs to be removed to ppm level or even lower through adsorption for downstream application. However, in long-term use, the adsorbent will reach saturation and cannot continue to adsorb ammonia, and needs to be regularly desorbed and regenerated. In the prior art, more than 2 adsorption columns are usually required to be set up to stagger "adsorption-desorption" cycles to meet the long-term gas supply of the ammonia decomposition hydrogen production system, and in the desorption process of the existing process, not only N2 needs to be prepared to purge the adsorption column, increasing the system raw material cost and energy consumption, but also the purging effect is poor; ammonia is still inevitably released during the adsorption process, and if not treated, it will still be directly discharged into the atmosphere or converted into high-concentration nitrogen oxides (NOx) and discharged into the atmosphere, causing environmental pollution.

[0003] CN208308426U discloses an ammonia decomposition hydrogen production device, comprising a bottom plate, a box, a first adsorption tower and a second adsorption tower, the box is located above the bottom plate, a heat insulating plate is arranged in the box, a heat exchanger is arranged above the heat insulating plate, a valve is arranged between the heat exchanger and the box, one end of the heat exchanger penetrates through the box and is provided with a valve, the other end of the heat exchanger penetrates through the partition plate and is connected with the inside of the decomposition furnace, a gas pipe is arranged at the lower end of the decomposition furnace, the gas pipe penetrates through the box and is connected with the first adsorption tower and the second adsorption tower, molecular sieves are arranged in the first adsorption tower and the second adsorption tower, and the first adsorption tower and the second adsorption tower are connected through the valve. The patent converts liquid ammonia into ammonia gas through the heat exchanger, then converts the ammonia gas into nitrogen and hydrogen through the decomposition furnace to reduce the environmental damage of ammonia gas, then the hydrogen and nitrogen gas after decomposition are introduced into the adsorption tower for adsorption, and the gas purity of hydrogen and nitrogen is improved. The ammonia decomposition hydrogen production device of the patent needs to additionally use nitrogen to purge the adsorption tower, the raw material cost of the system is high, and there is a risk of ammonia gas leakage and environmental damage in the adsorption process. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides an ammonia decomposition hydrogen production system and method based on double adsorption. The system uses double adsorption device and two-stage separation technology. During adsorption, ammonia gas and nitrogen oxides are not discharged, and nitrogen gas is not needed for purging. The system has low operating cost, low energy consumption and good purging effect.

[0005] The application adopts the following technical solutions:

[0006] An ammonia decomposition hydrogen production system based on double adsorption, comprising an ammonia storage device, a heat exchange device, an ammonia decomposition reaction device, a first compression device, a first adsorption device, a first buffer device, a second adsorption device and a second buffer tank. The liquid outlet of the ammonia storage device is connected with the gas inlet of the ammonia decomposition reaction device through the cold liquid channel of the heat exchange device. The gas outlet of the ammonia decomposition reaction device is connected with the first compression device through the gas channel of the heat exchange device. The liquid ammonia discharged from the ammonia storage device and the mixed gas discharged from the ammonia decomposition reaction device are subjected to heat exchange through the heat exchange device, and the gas after heat exchange is introduced into the first compression device.

[0007] The outlet of the first compression device is connected with the adsorption inlet of the first adsorption device, and the adsorption outlet of the first adsorption device is connected with the inlet of the first buffer device.

[0008] The second adsorption device comprises a plurality of adsorption columns arranged in parallel, the outlet of the first buffer device is in communication with the adsorption inlets of the plurality of adsorption columns arranged in parallel, a control valve is arranged on the pipeline of the adsorption outlet of each adsorption column, a control valve is arranged on the pipeline between the adsorption inlet of each adsorption column and the first buffer device, the adsorption outlets of the plurality of adsorption columns are in communication with each other, a control valve is arranged between the adsorption outlets of two adjacent adsorption columns, the adsorption inlet of each adsorption column is also in communication with the inlet of the second buffer device, a control valve is arranged between the adsorption inlet of each adsorption column and the second buffer device; the outlet of the second buffer device is in communication with the adsorption outlet of the first adsorption device, the adsorption inlet of the first adsorption device is also in communication with the gas inlet of the ammonia decomposition reaction device through a pipeline, and a control valve is arranged on the pipeline between the adsorption inlet of the first adsorption device and the ammonia decomposition reaction device; the second buffer device can guide the gas adsorbed by the second adsorption device into the first adsorption device to purge the first adsorption device, and the purged gas is discharged into the ammonia decomposition reaction device through the adsorption inlet of the first adsorption device.

[0009] Preferably, the heat exchange device comprises a first heat exchanger and a second heat exchanger, the first heat exchanger is provided with a first cold liquid inlet, a first cold liquid outlet, a first hot gas inlet and a first hot gas outlet, the first cold liquid inlet and the first cold liquid outlet form a pair of communication, and the first hot gas inlet and the first hot gas outlet form a pair of communication; the second heat exchanger is provided with a second cold gas inlet, a second cold gas outlet, a second hot gas inlet and a second hot gas outlet, the second cold gas inlet and the second cold gas outlet form a pair of communication, and the second hot gas inlet and the second hot gas outlet form a pair of communication; the liquid outlet of the ammonia storage device is in communication with the gas inlet of the ammonia decomposition reaction device in sequence through the first cold liquid inlet, the first cold liquid outlet, the second cold gas inlet and the second cold gas outlet, and the gas outlet of the ammonia decomposition reaction device is in communication with the inlet of the first compression device in sequence through the second hot gas inlet, the second hot gas outlet, the first hot gas inlet and the first hot gas outlet.

[0010] A second compression device is further arranged on the pipeline between the first adsorption device and the gas inlet of the ammonia decomposition reaction device.

[0011] An adjusting valve is arranged on the pipeline between the first cold liquid outlet and the second cold gas inlet; an air cooling device is further arranged on the pipeline between the second hot gas outlet and the first hot gas inlet.

[0012] The inlet end and the outlet end of the first compression device and the inlet end and the outlet end of the second compression device are all provided with buffer tanks.

[0013] The ammonia decomposition reaction device is provided with a ruthenium-based catalyst.

[0014] Preferably, the first adsorption device comprises a first temperature adsorption column and a second temperature adsorption column arranged in parallel, and first, second, third, fourth, fifth, sixth, seventh and eighth control valves arranged at the adsorption inlet and the adsorption outlet of the first adsorption device, the first temperature adsorption column is provided with a first temperature adsorption inlet and a first temperature adsorption outlet, the second temperature adsorption column is provided with a second temperature adsorption inlet and a second temperature adsorption outlet, a first pipeline is arranged between the first temperature adsorption inlet and the second temperature adsorption inlet, the first temperature adsorption outlet and the second temperature adsorption outlet are communicated through a second pipeline, a third pipeline is connected in parallel below the first pipeline, a fourth pipeline is arranged on the first temperature adsorption outlet, and a fifth pipeline is arranged on the second temperature adsorption outlet; the first control valve is arranged between the first compression device and the first temperature adsorption inlet, the third control valve is arranged between the first compression device and the second temperature adsorption inlet, the fifth control valve and the eighth control valve are arranged on the second pipeline, the second control valve is arranged on the fourth pipeline, the fourth control valve is arranged on the fifth pipeline, the sixth control valve is arranged between the first temperature adsorption inlet and the ammonia decomposition reaction device, and the seventh control valve is arranged between the second temperature adsorption inlet and the ammonia decomposition reaction device.

[0015] The fifth control valve is arranged between the first temperature adsorption outlet of the first temperature adsorption column and the second buffer device outlet, the eighth control valve is arranged between the second temperature adsorption outlet of the second temperature adsorption column and the second buffer device outlet, the second control valve is arranged between the first temperature adsorption outlet of the first temperature adsorption column and the first buffer device inlet, and the fourth control valve is arranged between the second temperature adsorption outlet of the second temperature adsorption column and the first buffer device inlet.

[0016] Preferably, the second adsorption device comprises a first pressure adsorption column and a second pressure adsorption column arranged in parallel, and ninth, tenth, eleventh, twelfth, thirteenth, fourteenth and fifteenth control valves arranged at the adsorption inlet and the adsorption outlet of the second adsorption device, the first pressure adsorption column is provided with a first pressure adsorption inlet and a first pressure adsorption outlet, the second pressure adsorption column is provided with a second pressure adsorption inlet and a second pressure adsorption outlet, a sixth pipeline is arranged between the first pressure adsorption inlet and the second pressure adsorption inlet, the first pressure adsorption outlet and the second pressure adsorption outlet are communicated through a seventh pipeline, an eighth pipeline is connected in parallel below the sixth pipeline, a ninth pipeline is communicated on the first pressure adsorption outlet, and a tenth pipeline is communicated on the second pressure adsorption outlet; the fourteenth control valve is arranged on the sixth pipeline close to the first pressure adsorption column, the fifteenth control valve is arranged on the sixth pipeline close to the second pressure adsorption column, the ninth control valve is arranged between the first buffer device inlet and the first pressure adsorption inlet, the eleventh control valve is arranged between the first buffer device inlet and the second pressure adsorption inlet, the thirteenth control valve is arranged on the seventh pipeline, the tenth control valve is arranged on the ninth pipeline, the twelfth control valve is arranged on the tenth pipeline, the fourteenth control valve is arranged between the first pressure adsorption inlet and the second buffer device inlet, and the fifteenth control valve is arranged between the second pressure adsorption inlet and the second buffer device inlet.

[0017] The second buffer device outlet is also communicated with external air.

[0018] A hydrogen production method using a dual-adsorption-based ammonia decomposition hydrogen production system, comprising the following steps:

[0019] S1, introducing liquid ammonia into a heat exchange device and heating the liquid ammonia to 200-700℃;

[0020] S2, introducing ammonia gas at 200-700℃ into an ammonia decomposition reaction device to perform ammonia decomposition reaction;

[0021] S3, discharging the decomposed mixed gas from the ammonia decomposition reaction device and cooling to room temperature;

[0022] S4, introducing the cooled mixed gas into a first compression device for compression;

[0023] S5, introducing the mixed gas compressed by the first compression device into a first adsorption device to adsorb the mixed gas until the first adsorption device is saturated, and introducing the adsorbed mixed gas into a first buffer device;

[0024] S6, the mixed gas buffered by the first buffering device is introduced into the first pressure adsorption column in the second adsorption device, so that the first pressure adsorption column adsorbs the mixed gas until the first pressure adsorption column reaches a saturated state, and at the same time of adsorption, 5-15% of the mixed gas in the first pressure adsorption column is introduced into the second pressure adsorption column to purge the second pressure adsorption column, and the purged gas is introduced into the second buffering device;

[0025] S7, the mixed gas buffered by the first buffering device is introduced into the second pressure adsorption column in the second adsorption device, so that the second pressure adsorption column adsorbs the mixed gas until the second pressure adsorption column reaches a saturated state, and at the same time of adsorption, 5-15% of the mixed gas in the second pressure adsorption column is introduced into the first pressure adsorption column to purge the second pressure adsorption column, and the purged gas is introduced into the second buffering device;

[0026] S8, the purged mixed gas in the second buffering device is introduced into the first adsorption device to purge the first adsorption device;

[0027] S9, the mixed gas after purging is introduced out of the first adsorption device and into the second compression device for compression, and then the compressed mixed gas is introduced back into the ammonia decomposition reaction device.

[0028] The technical scheme of the present application has the following advantages:

[0029] The present application adopts multiple heat exchange devices to heat ammonia, and multiple adsorption devices to adsorb mixed gas, corresponding control valves are arranged at different positions in the adsorption devices to control the flow direction of the mixed gas in the adsorption devices, the adsorption devices are connected through buffering devices, and the gas outlets of the adsorption devices are connected with the ammonia decomposition reaction device through the compression device, so that the mixed gas can be adsorbed by multiple adsorption devices, the whole system only provides hydrogen-nitrogen mixed gas (75% H2+25% N2) after deep adsorption removal of ammonia, further improving the discharge amount of hydrogen in the mixed gas, reducing the risk of environmental damage caused by other tail gas emissions and ammonia and nitrogen oxides, and improving the content and purity of hydrogen in the mixed gas; the gas after adsorption can be used to purge the saturated adsorption column, and the purged mixed gas can be returned to the ammonia decomposition reactor, realizing ammonia recycling of the desorption outlet gas, achieving 100% utilization of ammonia, and improving the hydrogen recovery rate of the hydrogen purification link; and the gas after adsorption is introduced back into the adsorption device and used for purging the adsorption device, without introducing additional gas source as purge gas, reducing the raw material cost of the system, improving the purging effect of the adsorption device, and reducing the risk of environmental pollution caused by ammonia emission into the air. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the present application, the drawings required to be used in the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0031] Figure 1 The whole structure schematic diagram of the ammonia decomposition hydrogen production system based on double adsorption of the present application (one);

[0032] Figure 2 The whole structure schematic diagram of the ammonia decomposition hydrogen production system based on double adsorption of the present application (two);

[0033] Figure 3 The whole structure schematic diagram of the ammonia decomposition hydrogen production system based on double adsorption of the present application (three).

[0034] The drawings are identified as follows:

[0035] 1-ammonia storage device, 11-stop valve, 12-liquid pump;

[0036] 2-heat exchange device, 21-first heat exchanger, 211-first cold liquid inlet, 212-first cold liquid outlet, 213-first hot gas inlet, 214-first hot gas outlet, 22-second heat exchanger, 221-second cold gas inlet, 222-second cold gas outlet, 223-second hot gas inlet, 224-second hot gas outlet, 23-regulating valve, 24-air cooling device;

[0037] 3-ammonia decomposition reaction device, 31-gas inlet, 32-gas outlet;

[0038] 4-first compression device;

[0039] 5-first adsorption device, 51-first temperature adsorption column, 511-first temperature adsorption inlet, 512-first temperature adsorption outlet, 52-second temperature adsorption column, 521-second temperature adsorption inlet, 522-second temperature adsorption outlet, 53-first pipeline, 54-second pipeline, 55-third pipeline, 56-fourth pipeline, 57-fifth pipeline;

[0040] 6-second adsorption device, 61-first pressure adsorption column, 611-first pressure adsorption inlet, 612-first pressure adsorption outlet, 62-second pressure adsorption column, 621-second pressure adsorption inlet, 622-second pressure adsorption outlet, 63-sixth pipeline, 64-seventh pipeline, 65-eighth pipeline, 66-ninth pipeline, 67-tenth pipeline;

[0041] 7-second compression device;

[0042] 8 - first buffer means;

[0043] 9 - second buffer means;

[0044] 10 - connection means;

[0045] a - first control valve, b - second control valve, c - third control valve, d - fourth control valve, e - fifth control valve, f - sixth control valve, g - seventh control valve, h - eighth control valve, i - ninth control valve, j - tenth control valve, k - eleventh control valve, m - twelfth control valve, n - thirteenth control valve, p - fourteenth control valve, q - fifteenth control valve. DETAILED DESCRIPTION

[0046] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0047] As Figure 1As shown, the application provides a dual-adsorption-based ammonia decomposition hydrogen production system, which comprises an ammonia storage device 1, a heat exchange device 2, an ammonia decomposition reaction device 3, a first compression device 4, a first adsorption device 5, a first buffer device 8, a second adsorption device 6, and a second buffer tank 9. The liquid outlet of the ammonia storage device 1 is communicated with the gas inlet 31 of the ammonia decomposition reaction device 3 through the cold liquid channel of the heat exchange device 2, and the gas outlet 32 of the ammonia decomposition reaction device 3 is communicated with the first compression device 4 through the gas channel of the heat exchange device 2. The liquid ammonia discharged from the ammonia storage device 1 and the mixed gas discharged from the ammonia decomposition reaction device 3 are subjected to heat exchange through the heat exchange device 2, and the gas after heat exchange is introduced into the first compression device 4. The first compression device 4 is communicated with the adsorption inlet of the first adsorption device 5, and the adsorption outlet of the first adsorption device 5 is communicated with the inlet of the first buffer device 8. The second adsorption device 6 comprises a plurality of parallelly arranged adsorption columns, the outlet of the first buffer device 8 is simultaneously communicated with the adsorption inlets of the plurality of parallelly arranged adsorption columns, a control valve is arranged on the pipeline between the adsorption inlet of each adsorption column and the first buffer device 8, the adsorption outlets of the plurality of adsorption columns are communicated with each other, a control valve is arranged between the adsorption outlets of two adjacent adsorption columns, the adsorption inlet of each adsorption column is also communicated with the inlet of the second buffer device 9, and a control valve is arranged between the adsorption inlet of the adsorption column and the second buffer device 9. The outlet of the second buffer device 9 is communicated with the adsorption outlet of the first adsorption device 5, the adsorption inlet of the first adsorption device 5 is also communicated with the gas inlet 31 of the ammonia decomposition reaction device 3 through a pipeline, and a control valve is arranged on the pipeline between the adsorption inlet of the first adsorption device 5 and the ammonia decomposition reaction device 3. The second buffer device 9 can introduce the gas after adsorption by the second adsorption device 6 into the first adsorption device 5 to purge the first adsorption device 5, and the purged gas is discharged into the ammonia decomposition reaction device 3 through the adsorption inlet of the first adsorption device 5.

[0048] The hydrogen production system of the present application can realize the simultaneous adsorption and desorption of the adsorption column, and the adsorption devices (the first adsorption device is temperature adsorption, and the second adsorption device is pressure adsorption) are connected in series, which further improves the content and purity of hydrogen in the mixed gas; and the mixed gas after being adsorbed by the second adsorption device 6 is used to purge the first adsorption device 5, after the purging is completed, the mixed gas is guided out of the first adsorption device 5 and compressed by the second compression device 7 and then flows back to the ammonia decomposition reactor inlet, converges with the preheated ammonia gas and then enters the ammonia decomposition device 3, realizing the ammonia recycling of the desorption outlet gas, realizing the 100% utilization of ammonia, improving the purging effect of the adsorption device, reducing the energy loss of the system and improving the energy utilization rate of the system. The whole system only provides hydrogen-nitrogen mixed gas (75% H2+25% N2) after deep adsorption and removal of ammonia, without other tail gas emission, realizing zero emission of the whole system, and also improving the purity of hydrogen in the mixed gas; the ammonia decomposition hydrogen production system provided by the present application realizes multiple adsorption by using multiple adsorption devices, and uses the gas after being adsorbed by the adsorption device to purge the saturated adsorption device, which reduces the raw material cost of the system and improves the purging effect of the system.

[0049] Further, the heat exchange device 2 comprises a first heat exchanger 21 and a second heat exchanger 22, the first heat exchanger 21 is provided with a first cold liquid inlet 211, a first cold liquid outlet 212, a first hot gas inlet 213 and a first hot gas outlet 214, the first cold liquid inlet 211 and the first cold liquid outlet 212 are a pair of communication, the first hot gas inlet 213 and the first hot gas outlet 214 are a pair of communication; the second heat exchanger 22 is provided with a second cold gas inlet 221, a second cold gas outlet 222, a second hot gas inlet 223 and a second hot gas outlet 224, the second cold gas inlet 221 and the second cold gas outlet 222 are a pair of communication, the second hot gas inlet 223 and the second hot gas outlet 224 are a pair of communication. The liquid outlet of the ammonia storage device 1 is communicated with the gas inlet 31 of the ammonia decomposition reaction device 3 in turn through the first cold liquid inlet 211, the first cold liquid outlet 212, the second cold gas inlet 221 and the second cold gas outlet 222, the gas outlet 32 on the ammonia decomposition reaction device 3 is communicated with the inlet of the first compression device 4 in turn through the second hot gas inlet 223, the second hot gas outlet 224, the first hot gas inlet 213 and the first hot gas outlet 214. Specifically, the first cold liquid inlet 211 and the first cold liquid outlet 212 are used to transport the liquid ammonia flowing out of the ammonia storage device 1, the first hot gas inlet 213 and the first hot gas outlet 214 are used to transport the mixed gas discharged from the ammonia decomposition reaction device 3 after being cooled by the second heat exchanger 22, wherein the first heat exchanger 21 can heat the liquid ammonia between the first cold liquid inlet 211 and the first cold liquid outlet 212 to vaporize and form ammonia gas, the heat exchange element of the first heat exchanger 21 can convert the heat of the mixed gas between the first hot gas inlet 213 and the first hot gas outlet 214 to the liquid ammonia flowing between the first cold liquid inlet 211 and the first cold liquid outlet 212, increase the temperature of the liquid ammonia to accelerate the vaporization of the liquid ammonia to generate ammonia gas, thereby reducing the heat required for subsequent heating of liquid ammonia, reducing heat consumption, and also effectively utilizing the heat generated by the system. In order to further control the amount of ammonia gas flowing into the second heat exchanger 22, so that the ammonia gas can fully decompose to generate sufficient hydrogen gas, the first heat exchanger 21 and the second heat exchanger 22 are provided with an adjusting valve 23, the adjusting valve 23 is used to adjust the gas flow of the ammonia gas generated by the vaporization of the liquid ammonia flowing into the second heat exchanger 22, thereby controlling the flow in the subsequent ammonia decomposition reaction device 3, so that the heat in the second heat exchanger 22 can be fully converted.The second cold gas inlet 221 and the second cold gas outlet 222 are used to transport the ammonia gas flowing out of the ammonia storage device 1 and vaporized by the first heat exchanger 21; the second hot gas inlet 223 and the second hot gas outlet 224 are used to transport the mixed gas discharged from the ammonia decomposition reaction device 3, wherein the heat exchange element of the second heat exchanger 22 can further heat the gas heated by the first heat exchanger 21 between the second cold gas inlet 221 and the second cold gas outlet 222 to reach the temperature required by the ammonia decomposition reaction, and the heat exchange element of the second heat exchanger 22 can transfer the heat of the mixed gas between the second hot gas inlet 223 and the second hot gas outlet 224 to the heat of the ammonia gas flowing between the second cold gas inlet 221 and the second cold gas outlet 222, which reduces the energy required to heat the ammonia gas to the ammonia decomposition reaction temperature and achieves the effect of saving energy loss; at the same time, the heat of the gas after ammonia decomposition is also effectively utilized, and the utilization rate of the system is improved.

[0050] In order to better control the inflow amount of liquid ammonia, so that the system can adjust the supply amount of liquid ammonia according to the actual production situation to obtain appropriate and sufficient hydrogen gas, the outlet of the ammonia storage device 1 is connected with a stop valve 11, and the stop valve 11 is connected with a liquid pump 12. Preferably, the liquid pump 12 is externally connected with a pressure transmission device, and through the pressure transmission device, the liquid pump 12 can adjust the inflow amount of liquid ammonia according to the pressure of the gas in the system, so as to ensure that the hydrogen gas generated by the reaction of the system can be within a stable interval, which improves the stability of the system and also improves the flexibility of the system, so as to ensure that the ammonia decomposition system has sufficient ammonia gas supply. One end of the liquid pump 12 is in communication with the first cold liquid inlet 211 of the first heat exchanger 21 through a pipeline.

[0051] The second compression device 7 is also arranged on the pipeline between the first adsorption device 5 and the gas inlet of the ammonia decomposition reaction device 3. The ammonia decomposition reaction device 3 is provided with a gas inlet 31 and a gas outlet 32, which are respectively arranged at two ends of the reaction main body of the ammonia decomposition reaction device 3. A connecting device 10 is arranged at a position close to the gas inlet 31 of the ammonia decomposition reaction device 3. One side of the connecting device 10 is connected with the reaction main body of the ammonia decomposition reaction device 3, and the other side is communicated with the second cold gas outlet 222 of the second heat exchanger 22. The ammonia gas which has reached the ammonia decomposition temperature and is discharged from the second heat exchanger 22 and the mixed gas which is discharged from the second compression device 7 can enter the ammonia decomposition reaction device 3 at the same time through the connecting device 10 to react so as to decompose the ammonia gas into hydrogen gas and nitrogen gas. The gas outlet 32 of the ammonia decomposition reaction device 3 is communicated with the second hot gas inlet 223 of the second heat exchanger 22. The mixed gas of the hydrogen gas and the nitrogen gas which is decomposed is then discharged into the second heat exchanger 22 to heat the ammonia gas which is introduced from the first heat exchanger 21. The ammonia decomposition reaction device 3 is internally provided with a ruthenium-based catalyst to accelerate the decomposition reaction of the ammonia gas, improve the completeness of the ammonia decomposition reaction and the hydrogen content in the mixed gas after decomposition.

[0052] After the ammonia gas heated by the second heat exchanger 22 flows into the ammonia decomposition reaction device 3 through the connecting device 10, the ammonia gas is decomposed to generate a mixed gas containing hydrogen, nitrogen and residual ammonia gas, and then the mixed gas is introduced into the second hot gas inlet 223 of the second heat exchanger 2 through the gas outlet of the ammonia decomposition reaction device 3, and then the heat of the mixed gas is transferred to the ammonia gas through the second heat transfer element in the second heat exchanger 22, so as to reduce the temperature of the mixed gas and increase the temperature of the ammonia gas, thereby reducing the energy loss. Since the gas after ammonia decomposition has a high temperature, in order to further reduce the temperature of the mixed gas, so that the mixed gas can be applied to the subsequent adsorption of the adsorption device and the purging of the adsorption column, and improve the adsorption effect and the purging effect of the adsorption device, the air cooling device 24 is connected between the second hot gas outlet 224 of the second heat exchanger 22 and the first hot gas inlet 213 of the first heat exchanger 21, and the air cooling device 24 is used to further reduce the temperature of the mixed gas discharged from the second heat exchanger 22, so that the mixed gas can be better applied to the subsequent adsorption and purging of the adsorption device, and at the same time, the energy required for the first heat exchanger 22 to convert heat is reduced, and the purging and adsorption effect is improved while the overall energy consumption of the system is reduced. After cooling by the air cooling device 24, the cooled mixed gas is then introduced into the first hot gas inlet 213 of the first heat exchanger 21, and then flows through the first heat transfer element in the first heat exchanger 21, and the first heat transfer element transfers the remaining heat of the cooled mixed gas to the liquid ammonia, so as to reduce the temperature of the mixed gas. The mixed gas with reduced temperature is then introduced into the first compression device 4 through the first hot gas outlet 214, and the first compression device 4 can compress the mixed gas with reduced temperature for subsequent adsorption and purging of the first adsorption device 5. Preferably, the inlet end and the outlet end of the first compression device 4 are both provided with a buffer tank, so as to improve the compression effect of the first compression device 4 on the gas.

[0053] The first adsorption device 5 comprises a first temperature adsorption column 51 and a second temperature adsorption column 52 arranged in parallel, and first to eighth control valves a, b, c, d, e, f, g and h arranged at the adsorption inlet and the adsorption outlet of the adsorption device 5, wherein the first temperature adsorption column 51 is provided with a first temperature adsorption inlet 511 and a first temperature adsorption outlet 512, the second temperature adsorption column 52 is provided with a second temperature adsorption inlet 521 and a second temperature adsorption outlet 522, a first pipeline 53 is arranged between the first temperature adsorption inlet 511 and the second temperature adsorption inlet 521, the first temperature adsorption outlet 512 and the second temperature adsorption outlet 522 are communicated through a second pipeline 54, a third pipeline 55 is connected in parallel below the first pipeline 53, a fourth pipeline 56 is arranged on the first temperature adsorption outlet 512, and a fifth pipeline 57 is arranged on the second temperature adsorption outlet 522; the first control valve a is arranged between the first compression device 4 and the first temperature adsorption inlet 511, the third control valve c is arranged between the first compression device 4 and the second temperature adsorption inlet 521, the fifth control valve e and the eighth control valve h are arranged on the second pipeline 54, the second control valve b is arranged on the fourth pipeline 56, the fourth control valve d is arranged on the fifth pipeline 57, the sixth control valve f is arranged between the first temperature adsorption inlet 511 and the ammonia decomposition reaction device 3, and the seventh control valve g is arranged between the second temperature adsorption inlet 521 and the ammonia decomposition reaction device 3. The fifth control valve e is arranged between the first temperature adsorption outlet 512 of the first temperature adsorption column 51 and the outlet of the second buffer device 9, the eighth control valve h is arranged between the second temperature adsorption outlet 522 of the second temperature adsorption column 52 and the outlet of the second buffer device 9, the second control valve b is arranged between the first temperature adsorption outlet 512 of the first temperature adsorption column 51 and the inlet of the first buffer device 8, and the fourth control valve d is arranged between the second temperature adsorption outlet 522 of the second temperature adsorption column 52 and the inlet of the first buffer device 8.

[0054] The second adsorption device 6 comprises a first pressure adsorption column 61 and a second pressure adsorption column 62 arranged in parallel, and a ninth control valve i, a tenth control valve j, an eleventh control valve k, a twelfth control valve m, a thirteenth control valve n, a fourteenth control valve p and a fifteenth control valve q arranged at the adsorption inlet and the adsorption outlet of the second adsorption device 6, wherein the first pressure adsorption column 61 is provided with a first pressure adsorption inlet 611 and a first pressure adsorption outlet 612, the second pressure adsorption column 62 is provided with a second pressure adsorption inlet 621 and a second pressure adsorption outlet 622, the first pressure adsorption inlet 611 and the second pressure adsorption inlet 621 are provided with a sixth pipeline 63, the first pressure adsorption outlet 612 and the second pressure adsorption outlet 622 are communicated through a seventh pipeline 64, the lower portion of the sixth pipeline 63 is provided with an eighth pipeline 65 in parallel, the first pressure adsorption outlet 612 is communicated with a ninth pipeline 66, and the second pressure adsorption outlet 622 is communicated with a tenth pipeline 67; the fourteenth control valve p is arranged at the position of the sixth pipeline 63 close to the first pressure adsorption column 61, the fifteenth control valve q is arranged at the position of the sixth pipeline 63 close to the second pressure adsorption column 62, the ninth control valve i is arranged between the first pressure adsorption inlet 611 and the inlet of the first buffer device 8, the eleventh control valve k is arranged between the second pressure adsorption inlet 621 and the inlet of the first buffer device 8, the thirteenth control valve n is arranged on the seventh pipeline 64, the tenth control valve j is arranged on the ninth pipeline 66, the twelfth control valve m is arranged on the tenth pipeline 67, the fourteenth control valve p is arranged between the first pressure adsorption inlet 611 and the inlet of the second buffer device 9, and the fifteenth control valve q is arranged between the second pressure adsorption inlet 621 and the inlet of the second buffer device 9.

[0055] The gas exhausted from the second adsorption device 6 after being adsorbed by the first pressure adsorption column 61 or the second pressure adsorption column 62 is buffered by the second buffer device 9, and then enters the second pipeline 53 of the first adsorption device 5, and the corresponding control valve is opened to purge the first temperature adsorption column 51 or the second temperature adsorption column 52; when the sixth control valve f is opened, the gas buffered by the second buffer device 9 is introduced into the first temperature adsorption column 51 and purges the first temperature adsorption column 51, and when the eighth control valve h is opened, the gas buffered by the second buffer device 9 is introduced into the second temperature adsorption column 52 and purges the second temperature adsorption column 52. By using the gas buffered by the second buffer device 9 to purge the first adsorption device 5, the utilization rate of the gas in the system can be improved, the risk of ammonia or nitrogen oxides being discharged into the air is reduced, the purging effect is improved, external nitrogen is not needed for purging, the energy consumption is reduced, and the energy utilization rate of the system is improved. The second buffer device 9 can also exhaust part of the gas after adsorption, and the gas after adsorption by the second adsorption device 6 is then introduced into the terminal equipment (such asFigure 2 and Figure 3 The terminal equipment includes hydrogen storage equipment, hydrogen refueling stations, fuel cells, and internal combustion engines. After being adsorbed by the first adsorption device 5 and the second adsorption device 6, the hydrogen purity and content in the gas are higher, thereby effectively improving the working efficiency of the terminal equipment.

[0056] After the mixed gas is compressed by the first compression device 4, it is introduced into the first adsorption device 5. At this time, the first control valve a is opened first, and the mixed gas is introduced into the first temperature adsorption column 51 for room temperature adsorption after passing through the first control valve a. Then, the second control valve b is opened, and the mixed gas after adsorption is completed is introduced into the first buffer device 8 for buffering, so as to be used for further adsorption in the second adsorption device 6. When the first temperature adsorption column 51 has completed adsorption and reached saturation, the first control valve a is closed, and the third control valve c is opened, so that the mixed gas enters the second temperature adsorption column 52 for adsorption. At the same time, the fourth control valve d is opened to discharge the mixed gas after adsorption is completed from the second temperature adsorption column 52 and introduce it into the first buffer device 8 for buffering.

[0057] By employing a series connection of the first adsorption device 5 and the second adsorption device 6, and installing a control valve between the adsorption outlets of adjacent adsorption columns, and connecting the adsorption inlet of the first adsorption device 5 to a compression device, adsorption and purging of the adsorption columns can be performed simultaneously. This ensures that the adsorption device continuously adsorbs the mixed gas, thereby improving the adsorption effect and working efficiency of the adsorption device. Furthermore, by connecting the first adsorption device 5 and the second adsorption device 6 in series, and using the gas adsorbed by the second adsorption device 6 to purge the first adsorption device 5, the purging effect of the first adsorption device 5 is improved. This allows the first adsorption device 5 to more effectively adsorb ammonia in the mixed gas, effectively utilizing the mixed gas generated by the system, while also improving the system's purging effect and ammonia decomposition efficiency, reducing the risk of harmful gas emissions. After the mixed gas, adsorbed by both the first adsorption device 5 and the second adsorption device 6, is purged from the first adsorption device 5, it is then discharged into the ammonia decomposition reactor 3 for ammonia decomposition reaction. This further reduces the ammonia content in the mixed gas and increases the hydrogen content, reducing the risk of ammonia emissions, improving the system's gas utilization rate, and achieving 100% ammonia recycling.

[0058] After adsorption through the first temperature adsorption column 51 and the second temperature adsorption column 52, the adsorbed mixed gas is buffered in the first buffer device 8, and then enters the second gas pressure adsorption device 6. The ninth control valve i is opened, and the mixed gas passes through the ninth control valve i and enters the first gas pressure adsorption column 61 for pressure adsorption. Then, the tenth control valve j and the thirteenth control valve n are opened. The mixed gas after adsorption is discharged from the first gas pressure adsorption column 61 through the tenth control valve j for subsequent hydrogen application. 5-15% of the mixed gas enters the second gas pressure adsorption column 62 through the thirteenth control valve n for purging the second gas pressure adsorption column 62. When the first gas pressure adsorption column 61 is saturated after adsorption, the ninth control valve i and the tenth control valve j are closed, and the eleventh control valve k and the twelfth control valve m are opened. The mixed gas treated by the first buffer device 8 enters the second gas pressure adsorption column 62 for adsorption, and 5-15% of the mixed gas is introduced into the first gas pressure adsorption column 61 through the thirteenth control valve n for purging. Further, when the purging of the first gas pressure adsorption column 61 is completed, the fourteenth control valve p is opened. The purged mixed gas is discharged from the first gas pressure adsorption outlet 611 of the first gas pressure adsorption column 61 and enters the second buffer device 9 for buffering. When the purging of the second gas pressure adsorption column 62 is completed, the fifteenth control valve q is opened. The purged mixed gas is discharged from the second gas pressure adsorption outlet 621 of the second gas pressure adsorption column 62 and enters the second buffer device 9 for buffering. One outlet of the second buffer device 9 is in communication with the second pipeline 54 of the first adsorption device 5. According to the purging conditions of the first temperature adsorption column 51 and the second temperature adsorption column 52 at this time, the fifth control valve e in communication with the first temperature adsorption column 51 is opened, or the eighth control valve h in communication with the second temperature adsorption column 52 is opened. According to the adsorption conditions, the gas after adsorption by the second adsorption device 6 is introduced into the first temperature adsorption column 51 or the second temperature adsorption column 52 for purging. The purged gas is introduced into the second compression device 7 through the opened sixth control valve f or the seventh control valve g.

[0059] When the second temperature adsorption column 52 is saturated and the first temperature adsorption column 51 is completed, the adsorption can be performed again: that is, the second temperature adsorption column 52 is adsorbed first, and when the second temperature adsorption column 52 is saturated, the first temperature adsorption column 51 is adsorbed; similarly, when the second pressure adsorption column 62 is saturated and the first pressure adsorption column 61 is completed, the adsorption can be performed again: that is, the second pressure adsorption column 62 is adsorbed first, and the first pressure adsorption column 61 is purged, and after the purge is completed, the fourteenth control valve p is opened to guide the purged gas into the second buffer device 9 for buffering; when the second pressure adsorption column 62 is saturated, the first pressure adsorption column 61 is adsorbed, and the second pressure adsorption column 62 is purged; after the purge is completed, the fifteenth control valve q is opened, and the purged mixed gas is guided out through the second pressure adsorption inlet 621 of the second pressure adsorption column 62 and enters the second buffer device 9 through the fifteenth control valve q.

[0060] When the purge of the first temperature adsorption column 51 and the second temperature adsorption column 52 is completed, the remaining mixed gas after the purge and adsorption is then compressed by the second compression device 7, and then introduced into the ammonia decomposition reaction device 3 for ammonia decomposition reaction of the remaining residual ammonia; the remaining ammonia is prevented from flowing into the atmosphere or forming nitrogen oxides by heating combustion to form environmental impact, achieving 100% recycling of ammonia; and the mixed gas after ammonia decomposition is adsorbed by the first adsorption device 5 and the second adsorption device 6, so that the hydrogen-nitrogen mixed gas introduced into the gas collection device is deeply adsorbed and ammonia is removed, reducing the emission of harmful gases; at the same time, the ammonia decomposition hydrogen production system of the present application uses mixed gas and valves in cooperation, and uses temperature adjustment and gas pressure to adsorb the gas respectively, which improves the purity of hydrogen in the mixed gas after ammonia decomposition reaction, and uses the reacted gas to purge the adsorption column, without additional nitrogen purge, reducing the system use cost, and also improving the purge effect, so that the adsorption column has good adsorption capacity.

[0061] In addition, the present application also discloses a hydrogen production method of an ammonia decomposition hydrogen production system based on double adsorption, comprising the following steps:

[0062] S1, introducing liquid ammonia into the heat exchange device 2 and heating the liquid ammonia to 200-700℃;

[0063] S2, introducing the ammonia gas at 200-700℃ into the ammonia decomposition reaction device 3 for ammonia decomposition reaction;

[0064] S3, discharging the decomposed mixed gas from the ammonia decomposition reaction device 3 and cooling to room temperature;

[0065] S4, introducing the cooled mixed gas into the first compression device 4 for compression;

[0066] S5, the mixed gas compressed by the first compression device 4 is introduced into the first adsorption device 5 to adsorb the mixed gas until the first adsorption device 5 reaches saturation, and the mixed gas after adsorption is introduced into the first buffer device 8;

[0067] S6, the mixed gas buffered by the first buffer device 8 is introduced into the first pressure adsorption column 61 of the second adsorption device 6, so that the first pressure adsorption column 61 adsorbs the mixed gas until the first pressure adsorption column 61 reaches saturation, and at the same time of adsorption, 5-15% of the mixed gas at the outlet of the first pressure adsorption column 61 is introduced into the second pressure adsorption column 62 to purge the second pressure adsorption column 62, and the purged gas is introduced into the second buffer device 9;

[0068] S7, the mixed gas buffered by the first buffer device 8 is introduced into the second pressure adsorption column 62 of the second adsorption device 6, so that the second pressure adsorption column 62 adsorbs the mixed gas until the second pressure adsorption column 62 reaches saturation, and at the same time of adsorption, 5-15% of the mixed gas in the second pressure adsorption column 62 is introduced into the first pressure adsorption column 61 to purge the second pressure adsorption column 62, and the purged gas is introduced into the second buffer device 9;

[0069] S8, the mixed gas purged in the second buffer device 9 is introduced into the first adsorption device 5 to purge the first adsorption device 5;

[0070] S9, the mixed gas after purging is introduced out of the first adsorption device 5 and introduced into the second compression device 7 for compression, and then the compressed mixed gas is introduced into the ammonia decomposition reaction device 3 for ammonia decomposition reaction.

[0071] In step S5, the mixed gas is introduced into the first adsorption device 5 to be adsorbed by opening the first control valve a of the first adsorption device 5, and when the first adsorption device 5 is saturated, the remaining gas is introduced into the first buffer device 8 through the second control valve b; in step S6, the ninth control valve i is opened to introduce the mixed gas in the first buffer device 8 into the first pressure adsorption column 61 to be adsorbed, and the adsorbed gas is discharged from the first pressure adsorption column 61 by opening the tenth control valve j; 5-15% of the mixed gas is introduced into the second pressure adsorption column 62 to be purged by opening the thirteenth control valve n, and the purged mixed gas is discharged from the second pressure adsorption column 62 and introduced into the second compression device 9 by opening the fifteenth control valve q; in step S7, the eleventh control valve k is opened to introduce the mixed gas from the first buffer device 8 into the second pressure adsorption column 62 to be adsorbed, 5-15% of the mixed gas is used to purge the first pressure adsorption column 61 by opening the thirteenth control valve n, and the purged mixed gas is introduced into the second buffer device 9 by opening the fourteenth control valve p; in step S8, the control valve on the adsorption outlet of the first adsorption device 5 is opened to introduce the mixed gas in the second buffer device 9 into the first adsorption device 5 to be purged; in step S9, when the purging of the first adsorption device 5 is completed, the control valve on the adsorption inlet of the first adsorption device 5 is opened to introduce the purged gas, which is introduced into the second compression device 7 and then into the ammonia decomposition reaction device 3, to complete the reuse of the purged gas.

[0072] Similarly, the second pressure adsorption column 62 can be first adsorbed, and the first pressure adsorption column 61 is purged at the same time, the purged mixed gas is discharged from the first pressure adsorption column 61 through the fourteenth control valve p and introduced into the second buffer device 9; when the second pressure adsorption column 62 is saturated, the first pressure adsorption column 61 is adsorbed, and the second pressure adsorption column 62 is purged, the purged mixed gas is discharged from the second pressure adsorption column 62 through the fifteenth control valve q and introduced into the second buffer device 9.

[0073] Obviously, the above embodiments are only examples for clearly illustrating, but not limitation on the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments need not and cannot be exhausted. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A hydrogen production system based on ammonia decomposition using dual adsorption, characterized in that, The device includes an ammonia storage device (1), a heat exchange device (2), an ammonia decomposition reaction device (3), a first compression device (4), a first adsorption device (5), a first buffer device (8), a second adsorption device (6), and a second buffer device (9). The outlet of the ammonia storage device (1) is connected to the gas inlet (31) of the ammonia decomposition reaction device (3) through the cold liquid channel on the heat exchange device (2). The gas outlet (32) of the ammonia decomposition reaction device (3) is connected to the first compression device (4) through the gas channel on the heat exchange device (2). The liquid ammonia discharged from the ammonia storage device (1) and the mixed gas discharged from the ammonia decomposition reaction device (3) exchange heat through the heat exchange device (2) and the mixed gas after heat exchange is introduced into the first compression device (4). The outlet of the first compression device (4) is connected to the adsorption inlet of the first adsorption device (5), and the adsorption outlet of the first adsorption device (5) is connected to the inlet of the first buffer device (8). The second adsorption device (6) includes multiple adsorption columns arranged in parallel. The outlet of the first buffer device (8) is simultaneously connected to the adsorption inlets of the multiple adsorption columns arranged in parallel. A control valve is correspondingly provided on the pipeline between the adsorption inlet of each adsorption column and the first buffer device (8). A control valve is correspondingly provided on the pipeline between the adsorption outlet of each adsorption column. The adsorption outlets of the multiple adsorption columns are interconnected. A control valve is provided between the adsorption outlets of two adjacent adsorption columns. The adsorption inlet of each adsorption column is also connected to the inlet of the second buffer device (9). A control valve is also provided between the adsorption inlet of the adsorption column and the second buffer device (9). The outlet of the second buffer device (9) is connected to the adsorption outlet of the first adsorption device (5), and the adsorption inlet of the first adsorption device (5) is also connected to the gas inlet (31) of the ammonia decomposition reaction device (3) through a pipeline. A control valve is provided on the pipeline between the adsorption inlet of the first adsorption device (5) and the ammonia decomposition reaction device (3). The second buffer device (9) can introduce the gas adsorbed by the second adsorption device (6) into the first adsorption device (5) to purge the first adsorption device (5). The purged gas is discharged into the ammonia decomposition reaction device (3) through the adsorption inlet of the first adsorption device (5).

2. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 1, characterized in that: The heat exchange device (2) includes a first heat exchanger (21) and a second heat exchanger (22). The first heat exchanger (21) is provided with a first cold liquid inlet (211), a first cold liquid outlet (212), a first hot gas inlet (213), and a first hot gas outlet (214). The first cold liquid inlet (211) and the first cold liquid outlet (212) are connected as a pair, and the first hot gas inlet (213) and the first hot gas outlet (214) are connected as a pair. The second heat exchanger (22) is provided with a second cold gas inlet (221), a second cold gas outlet (222), a second hot gas inlet (223), and a second hot gas outlet (224). The second cold gas inlet (221) and the second hot gas outlet (224) are connected as a pair. The second cold air outlet (222) is connected to the second hot air inlet (223) and the second hot air outlet (224) are connected to the second hot air outlet (224); the liquid outlet of the ammonia storage device (1) is connected to the gas inlet (31) of the ammonia decomposition reaction device (3) in sequence through the first cold liquid inlet (211), the first cold liquid outlet (212), the second cold air inlet (221) and the second cold air outlet (222); the gas outlet (32) of the ammonia decomposition reaction device (3) is connected to the inlet of the first compression device (4) in sequence through the second hot air inlet (223), the second hot air outlet (224), the first hot air inlet (213) and the first hot air outlet (214).

3. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 2, characterized in that: A second compression device (7) is also provided on the pipeline between the first adsorption device (5) and the gas inlet of the ammonia decomposition reaction device (3). A regulating valve (23) is provided on the pipeline between the first cold liquid outlet (212) and the second cold air inlet (221); an air-cooling device (24) is also provided on the pipeline between the second hot air outlet (224) and the first hot air inlet (213).

4. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 3, characterized in that: The inlet and outlet ends of the first compression device (4) and the inlet and outlet ends of the second compression device (7) are all provided with buffer tanks.

5. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 1, characterized in that: The ammonia decomposition reaction device (3) is equipped with a ruthenium-based catalyst.

6. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 1, characterized in that: The first adsorption device (5) includes a first temperature adsorption column (51) and a second temperature adsorption column (52) arranged in parallel, and a first control valve (a), a second control valve (b), a third control valve (c), a fourth control valve (d), a fifth control valve (e), a sixth control valve (f), a seventh control valve (g), and an eighth control valve (h) arranged at the adsorption inlet and adsorption outlet of the first adsorption device (5). The first temperature adsorption column (51) is provided with a first temperature adsorption inlet (511) and a first temperature adsorption outlet (512), and the second temperature adsorption column (52) is provided with a second temperature adsorption inlet (521) and a second temperature adsorption outlet (522). A first pipe (53) is provided between the first temperature adsorption inlet (511) and the second temperature adsorption inlet (521), and the first temperature adsorption outlet (512) and the second temperature adsorption outlet (522) are connected through a second pipe (54). A third pipe (55) is connected in parallel below the first temperature adsorption outlet (512), a fourth pipe (56) is provided on the first temperature adsorption outlet (512), and a fifth pipe (57) is provided on the second temperature adsorption outlet (522); a first control valve (a) is provided between the first compression device (4) and the first temperature adsorption inlet (511), a third control valve (c) is provided between the first compression device (4) and the second temperature adsorption inlet (521), a fifth control valve (e) and an eighth control valve (h) are provided on the second pipe (54), a second control valve (b) is provided on the fourth pipe (56), a fourth control valve (d) is provided on the fifth pipe (57), a sixth control valve (f) is provided between the first temperature adsorption inlet (511) and the ammonia decomposition reaction device (3), and a seventh control valve (g) is provided between the second temperature adsorption inlet (521) and the ammonia decomposition reaction device (3); The fifth control valve (e) is located between the first temperature adsorption outlet (512) of the first temperature adsorption column (51) and the outlet of the second buffer device (9). The eighth control valve (h) is located between the second temperature adsorption outlet (522) of the second temperature adsorption column (52) and the outlet of the second buffer device (9). The second control valve (b) is located between the first temperature adsorption outlet (512) of the first temperature adsorption column (51) and the inlet of the first buffer device (8). The fourth control valve (d) is located between the second temperature adsorption outlet (522) of the second temperature adsorption column (52) and the inlet of the first buffer device (8).

7. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 6, characterized in that: The second adsorption device (6) includes a first pressure adsorption column (61) and a second pressure adsorption column (62) arranged in parallel, and a ninth control valve (i), a tenth control valve (j), an eleventh control valve (k), a twelfth control valve (m), a thirteenth control valve (n), a fourteenth control valve (p), and a fifteenth control valve (q) arranged at the adsorption inlet and adsorption outlet of the second adsorption device (6). The first pressure adsorption column (61) is provided with a first pressure adsorption inlet (611) and a first pressure adsorption outlet (612), and the second pressure adsorption column (62) is provided with a second pressure adsorption inlet (621) and a second pressure adsorption outlet (622). A sixth pipe (63) is provided between the first pressure adsorption inlet (611) and the second pressure adsorption inlet (621). The first pressure adsorption outlet (612) and the second pressure adsorption outlet (622) are connected through a seventh pipe (64). An eighth pipe (65) is connected in parallel below the sixth pipe (63), and a ninth pipe is connected to the first pressure adsorption outlet (612). (66), the second pressure adsorption outlet (622) is connected to the tenth pipe (67); the sixth pipe (63) is provided with the fourteenth control valve (p) near the first pressure adsorption column (61), the sixth pipe (63) is provided with the fifteenth control valve (q) near the second pressure adsorption column (62), the ninth control valve (i) is provided between the inlet of the first buffer device (8) and the first pressure adsorption inlet (611), the eleventh control valve (k) is provided between the inlet of the first buffer device (8) and the second pressure adsorption inlet (621), the thirteenth control valve (n) is provided on the seventh pipe (64), the tenth control valve (j) is provided on the ninth pipe (66), the twelfth control valve (m) is provided on the tenth pipe (67), the fourteenth control valve (p) is provided between the first pressure adsorption inlet (611) and the inlet of the second buffer device (9), and the fifteenth control valve (q) is provided between the second pressure adsorption inlet (621) and the inlet of the second buffer device (9).

8. The ammonia decomposition hydrogen production system based on dual adsorption according to claim 7, characterized in that: The outlet of the second buffer device (9) is also connected to the outside air.

9. A method for producing hydrogen using the ammonia decomposition hydrogen production system based on dual adsorption as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Introduce liquid ammonia into the heat exchange device (2) and heat the liquid ammonia to between 200 and 700°C; S2. Introduce ammonia gas at 200-700℃ into the ammonia decomposition reaction apparatus (3) to carry out the ammonia decomposition reaction; S3. Discharge the decomposed mixed gas from the ammonia decomposition reaction device (3) and cool it to room temperature; S4. The cooled mixed gas is introduced into the first compression device (4) for compression; S5. The mixed gas after being compressed by the first compression device (4) is introduced into the first adsorption device (5) to adsorb the mixed gas until the first adsorption device (5) reaches saturation, and the mixed gas after adsorption is introduced into the first buffer device (8). S6. The mixed gas after being buffered by the first buffer device (8) is introduced into the first pressure adsorption column (61) of the second adsorption device (6), so that the first pressure adsorption column (61) adsorbs the mixed gas until the first pressure adsorption column (61) reaches saturation. At the same time as adsorption, 5-15% of the mixed gas at the outlet of the first pressure adsorption column (61) is passed to the second pressure adsorption column (62) to purge the second pressure adsorption column (62). At the same time, the purged gas is introduced into the second buffer device (9). S7. The mixed gas after being buffered by the first buffer device (8) is introduced into the second pressure adsorption column (62) of the second adsorption device (6), so that the second pressure adsorption column (62) adsorbs the mixed gas until the second pressure adsorption column (62) reaches saturation. At the same time as adsorption, 5 to 15% of the mixed gas in the second pressure adsorption column (62) is passed to the first pressure adsorption column (61) to purge the first pressure adsorption column (61), and the purged gas is introduced into the second buffer device (9). S8. The mixed gas after purging in the second buffer device (9) is introduced into the first adsorption device (5) to purge the first adsorption device (5); S9. After the purging is completed, the mixed gas is discharged from the first adsorption device (5) and compressed by the second compression device (7). Then the compressed mixed gas is reintroduced into the ammonia decomposition reaction device (3).

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