CN114588749A

CN114588749A - Extracting H from synthetic ammonia purge gas2And NH3Pressure swing adsorption process of full temperature range simulated rotary moving bed

Info

Publication number: CN114588749A
Application number: CN202210259602.3A
Authority: CN
Inventors: 汪兰海; 陈运; 唐金财
Original assignee: Zhejiang Tiancai Yunji Technology Co ltd
Current assignee: Zhejiang Tiancai Yunji Technology Co ltd
Priority date: 2022-03-16
Filing date: 2022-03-16
Publication date: 2022-06-07
Anticipated expiration: 2042-03-16
Also published as: CN114588749B

Abstract

The invention discloses a method for extracting H from synthetic ammonia purge gas₂And NH₃The full temperature range simulated rotary moving bed pressure swing adsorption (FTrSRMPSA) process is characterized in that a medium-high temperature pressure swing adsorption ammonia concentration system and a middle gas pressure swing adsorption hydrogen extraction system which are arranged in the center of an upper multi-channel rotary valve and a lower multi-channel rotary valve and are arranged on a circular rotary tray around the middle high temperature pressure swing adsorption ammonia concentration system and the middle gas pressure swing adsorption hydrogen extraction system are formed by a plurality of axial flow fixed bed adsorption towers and a rotating speed mechanism, so that gas flowing through the rotary valve channels, pipelines at the inlet and outlet ends of the adsorption towers and adsorption beds can complete mass transfer of respective adsorption and desorption steps at the inlet and outlet positions of each adsorption tower and each adsorption bed layer while rotating, a pressure swing adsorption process of a simulated rotary moving bed is formed, and the pressure swing adsorption process of the axial flow fixed bed is realizedSimulated rotary moving bed pressure swing adsorption process on an attached basis to obtain H in high purity and high yield₂And NH₃The product is returned to the production process of the synthetic ammonia for recycling.

Description

Extracting H from synthetic ammonia purge gas2And NH3Pressure swing adsorption process of full temperature range simulated rotary moving bed

Technical Field

The invention relates to the field of recycling of synthetic ammonia purge gas, in particular to a method for extracting H from synthetic ammonia purge gas₂And NH₃The full temperature range simulation rotary moving bed pressure swing adsorption process.

Background

In the production of synthetic ammonia, hydrogen (H)₂) With nitrogen (N)₂) Synthetic ammonia (NH) is generated under the action of high temperature and high pressure and a catalyst₃) However, the conversion of synthetic ammonia is only 1/3. In order to improve the yield of the synthetic ammonia, the unreacted mixed hydrogen and nitrogen gas is taken as the recycle gas and returns to the production process of the synthetic ammonia to continue to participate in the reaction, and in the recycle process, some inert gas components which do not participate in the reaction, such as argon (Ar), helium (He) and the like, can be continuously accumulated to cause the reaction gas hydrogen (H) to be continuously accumulated₂) With nitrogen (N)₂) The partial pressure of (a) is reduced, which in turn leads to a reduction in the conversion of synthetic ammonia. Therefore, the recycle process is to reduce the content of inert gas components in the recycle gas by periodically discharging a part of the recycle gas, which is the purge gas (CDF), to maintain the conversion rate of the synthesis ammonia. Generally speaking, 180-240 Nm is discharged for each ton of synthetic ammonia product³The purge gas of (2). If ammonia (NH) in the purge gas₃) Purifying or concentrating by 90% or more for synthetic ammonia production, and recovering 100 million Nm/year calculated by 1.5 million tons/year synthetic ammonia production³The advantages of the purge gas are quite remarkable.

The typical composition of the synthetic ammonia purge gas is 60-63% (v/v) H ₂3 to 10% of methane (CH)₄）、20~21%N₂、2~3%Ar、2~3%NH₃And a small amount of He and krypton (Kr) at a temperature of 200-300 ℃ and a pressure of 3-12 MPa. Generally, methods for treating the purge gas of synthetic ammonia include direct use as fuel gas, membrane separation, cryogenic separation and Pressure Swing Adsorption (PSA), wherein the last three methods are methods capable of recovering NH as an effective component₃And H₂Instead of being used directly as fuel gas.

The membrane separation method fully utilizes the characteristic of high pressure of the synthetic ammonia purge gas, and the effective H flows out from the first-stage permeation side of the membrane separation system formed by the multistage series hollow fiber membrane modules₂The concentration of the components can reach 95-98%, the yield is up to more than 90%, and methane and N are enriched by flowing out from the non-permeable side of the membrane component of the last stage₂Ar, etc. non-permeating gasAnd (3) outputting the gas as fuel gas, wherein if a multistage membrane system of American Prism is adopted, high-pressure nitrogen-rich gas and low-pressure nitrogen-rich gas can respectively flow out from a non-permeation side of secondary membrane separation in the multistage membrane system, and enter a second-stage synthesis process in the synthetic ammonia production process for recycling. However, the membrane separation process still has several significant drawbacks, first, the small amount of ammonia (NH) in the syngas purge gas₃) The membrane cannot be directly recycled through a membrane separation system, but has obvious pollution or embrittlement on the membrane material and the ammonia corrosion effect with moisture in the membrane material, so that the membrane flux and the service life of the membrane are greatly shortened. And then, the purge gas enters a membrane system, ammonia in the purge gas is removed to be less than 0.1-5 ppm through pretreatment procedures such as water washing, adsorption purification and the like, industrial ammonia water with the concentration of 20% is formed at the bottom of a water washing tower and is transported out, certain water and other liquid drops and the like are brought into the system through the water washing, and the water and the liquid drops and other impurity components are removed completely through the adsorption drying purification procedures, otherwise the membrane system is polluted. However, although the process of washing ammonia with water is relatively mature, the formed ammonia water has extremely strong corrosiveness, including the need of corrosion prevention of the filler in the absorption tower and the materials and equipment inside and outside the absorption tower, and further the investment is increased. In addition, because the ammonia concentration in the purge gas is low, the water washing pressure needs to be increased or the temperature needs to be reduced, the higher the pressure is, the larger the investment and cost of water washing equipment is, the lower the temperature is, the larger the cooling amplitude of the high-temperature purge gas is, the larger the energy consumption is, and the larger the fluctuation of the ammonia content in the purge gas is, the more often reaches 5% or even more than 8%, so that the load of the subsequent adsorption purification process is increased to shorten the service life of the adsorbent, and in severe cases, ammonia gas, water and the like penetrate through to enter a membrane separation system to cause the loss of a membrane; secondly, the flux of the membrane separation system is relatively small, multiple stages of membranes are connected in series or in parallel to adapt to large-scale purge gas treatment, the investment is greatly increased, the service life of the membranes is relatively short, the replacement frequency is relatively high, and the operation cost is high; thirdly, the purity of the hydrogen product gas obtained by the membrane separation system is not very high, generally 95-98%, and if high-purity H is needed₂The investment of the membrane system is increased and H is recovered₂The technical economy of (2) is affected; fourthly, the purge gas entering the membrane separation system needs to be heated to 60-80 ℃, the washing process is normal temperature, the purge gas is self-heated, therefore, the purge gas needs to be cooled before entering the washing process, and needs to be heated after the washing process, and the energy level waste of the purge gas is serious.

Cryogenic separation is a common method for many large-scale ammonia synthesis enterprises, can show scale effect, and is generally carried out at low temperature of 80-85K (-187 to-193 ℃) and high pressure of 6.0-7.0 MPa for low-temperature rectification to obtain liquefied natural gas, liquid nitrogen, argon and a mixture containing 90-95% of H in sequence₂The non-condensable gas is output as a crude hydrogen product, the yield is high, but the energy consumption is high, the investment is huge, the large-scale effect can be achieved in enterprises with matched large-scale air separation and cryogenic equipment, and the obtained crude hydrogen still needs to be purified by adopting PSA (pressure swing adsorption) or membrane separation and the like. The cryogenic separation is mainly used as a process for extracting argon, particularly for extracting the argon-rich synthetic ammonia purge gas, and the hydrogen is used as a byproduct, so that the comprehensive economic benefit is better. In addition, the deep cooling process is used for removing ammonia and CO from the purge gas after water washing₂、H₂The content of O and high boiling point impurity components is more strictly limited, and the operation safety accidents caused by pipeline blockage, equipment material pitting and the like due to the easiness in freezing or solidification at low temperature, ice brittleness and the like are prevented. Therefore, the pretreatment equipment and process matched with the cryogenic operation become very important.

The Pressure Swing Adsorption (PSA) method is a separation method with low energy consumption, high hydrogen purity and low investment and cost, and is more suitable for obtaining high-purity H from synthetic ammonia purge gas containing more than 60% of hydrogen concentration₂In case of (1), H₂The purity of the product can reach more than 99.9 percent. Compared with a membrane separation method or a cryogenic separation method, the PSA method has the greatest advantages that the pretreatment process comprising the processes of water absorption washing deamination, adsorption purification and the like can be omitted by adopting a composite adsorbent bed process, the corrosivity problem of ammonia water is avoided, the equipment adopts common carbon steel, the investment and maintenance cost is low, and high-purity H can be directly obtained₂And (5) producing the product. However, some conventional PSA separation methods still existThe obvious defects are as follows: firstly, the ammonia content in the exhausted gas fluctuates, which seriously restricts the PSA separation and extraction of H₂The efficiency of (c). The phenomenon that the ammonia gas is easy to adsorb and difficult to desorb and regenerate frequently occurs because of extremely strong adsorption capacity of the ammonia gas, so that the service life of the adsorbent is greatly shortened, and the adsorbent is easy to penetrate into H₂In the product gas. When the ammonia concentration in the synthetic ammonia purge gas exceeds 2-3%, a separate Temperature Swing Adsorption (TSA) or one-time adsorption purification is usually required to be used as PSA for separating and purifying H₂The investment is increased by the pretreatment of the working procedure; secondly, the traditional axial flow fixed bed PSA process has the contradiction that the product gas purity and the yield show inverse relation and H is achieved₂The product purity is more than 99.9 percent, the yield can be obviously reduced to less than 85 percent, in particular to a strong adsorbate component NH in the feed gas₃Under the working condition of coexistence with water, the yield is as low as 75-80%, even below; third, the purge gas contains H₂N with small relative separation coefficient₂With the Ar component, H is greatly influenced₂The purity of the product gas. Using special adsorbents, e.g. Carbon Molecular Sieves (CMSN)₂) Dynamic adsorption is carried out, so that more N can be adsorbed₂While Ar still enters the non-adsorbed phase gas, so that H₂The purity of the product gas is reduced. Adsorption tower with axial flow fixed bed layer, in the cyclic operation of adsorption and desorption of PSA, equilibrium adsorption NH is existed₃Kinetic adsorption of N₂And the complex working condition of selective adsorption of Ar by screening leads the design of the height-diameter ratio of the fixed bed layer and the adsorption tower to be particularly difficult. Although there is a full temperature range pressure swing adsorption (FTrPSA) process (patent No. CN 201610196432.3) that can partially solve or alleviate the contradiction of "inverse ratio between purity and yield" in equilibrium adsorption mechanism, for most of the dynamic adsorption or sieving adsorption mechanism, the FTrPSA separation method still has considerable limitations, mainly because the adsorption tower of the axial flow fixed bed has a high aspect ratio and the mass transfer path between the adsorbate component and the solid adsorbent is long, so that it is suitable for equilibrium adsorption but too long for dynamic adsorption, and it is easy to cause serious adsorbate penetration or co-adsorption or depthThe adsorption phenomenon reduces the purity and yield of the product H2; fourthly, the high pressure and the low temperature are more favorable for the working condition of small relative adsorption separation coefficient and are also favorable for H through the operation of multiple pressure equalization₂The purity and yield of the product gas are improved in a double mode, so that more adsorption towers, more high-pressure-resistant and high-speed-resistant air flow impact-resistant adsorbents, a combination of valves such as a program control valve and a regulating valve are required, particularly the program control valve, the probability of mechanical problems such as leakage, fatigue and abrasion is greatly increased when the pressure exceeds 5MPa, the stability and safety of the operation of the PSA device are greatly reduced, and the equipment investment is also greatly increased. On the contrary, the membrane separation method is more suitable for high-pressure working conditions, and has better stability and safety of operation.

In order to overcome some defects of the traditional fixed bed Pressure Swing Adsorption (PSA)/(FTrPSA) process, the PSA radial flow rotary adsorption (RWSAP) process is developed for PSA purification of H from the aspects of the process, the structure of an adsorption tower and a moving bed layer at home and abroad in succession₂The process, namely, the adsorbent is fixed in the adsorption container and does not move relatively, but the adsorbent as a whole rotates under the drive of the driving mechanism, the positions of the inlet and outlet rotating wheel adsorbers of which the material flow (gas) comprises synthetic ammonia purge gas as raw material gas, reverse purge gas, pressurized gas and the like are fixed, the cyclic operation of adsorption and desorption is simultaneously carried out in each adsorption sector chamber in different adsorbers respectively, the defects that the adsorbent is easy to lose and cannot be applied to the PSA separation or purification process in the classic moving bed adsorption (SMB) process are overcome, simultaneously compared with the traditional fixed bed PSA/FTrPSA process, the loading amount of the adsorbent is greatly reduced, the adsorption efficiency is improved, the product gas purity and the yield are improved, and the technical bottleneck that the purity and the yield are in inverse ratio existing in the fixed bed PSA process is broken through to a certain extent, meanwhile, the number of program control valves or regulating valves is greatly reduced, and the stability and the safety of the operation of the PSA device are improved. However, RWPSA processes also have significant limitations and disadvantages: first, the diameter and height (thickness) of the adsorption rotor are greatly limited, resulting in an insufficient scale of the adsorption process due to the large size of the adsorption rotorWhile RWPSA is essentially a moving bed, to achieve "steady-state" mass transfer for typical moving bed adsorption processes like circulating or fluidized beds, its axial or radial mass transfer diffusion capacity must be limited, and thus cannot meet the purification requirements for removing adsorbate components such as ammonia or water that predominate in equilibrium adsorption mechanisms. This feature is an advantage for axial flow or radial flow fixed bed processes; secondly, the rotary wheel PSA equipment is complicated to manufacture, especially the equipment with pressure equalizing is more complicated, the pressure equalizing time is not more than 2 times, and the rotary wheel PSA equipment is not suitable for purifying H by high-pressure purge gas PSA₂The operating mode, because to high pressure purge gas, 2 pressure-equalizing makes pressure variation range too big, can cause the air current velocity of flow in the adsorption tower too fast and take out solid adsorbent granule, brings the erosive wear for program control valve and governing valve or rotary valve, and the rotatory shearing force influence of adsorbent itself in addition, the pulverization of adsorbent granule can be quite serious, can cause corresponding rotary valve or control valve to appear leaking and potential safety hazard. At present, rotary wheel PSA equipment is mostly manufactured or monopolized by foreign companies, and the cost is higher; and thirdly, the method is suitable for the working conditions that the single adsorbate component is quickly adsorbed and quickly desorbed, and the adsorption mechanism of the adsorbate component mainly adopts dynamic adsorption, such as the purification of the tail gas containing VOCs. RWSPSA processes are less suitable for ammonia removal processes based on equilibrium adsorption, especially when the ammonia synthesis purge gas contains more NH with higher polarity₃、CO₂Impurity components such as water, hydrocarbon and the like need a long enough mass transfer path for adsorption, the impurity components cannot be fully adsorbed by an excessively short adsorbent bed layer in the RWSPSA process, so that deamination and impurity removal cannot reach the standard, meanwhile, the adsorbent cannot form a composite bed layer filled with various adsorbents in a fixed bed layer for treatment, and is particularly easily damaged by water drops in purge gas, high hydrocarbon and other easily-polluted liquid drops brought by a compressor; fourth, the adsorbent in RWPSA is prone to throwing and falling due to the presence of shear forces during rotation, resulting in drift or short flow of process stream gases in the adsorbent bed, which reduces mass transfer efficiency and makes the adsorbent more prone to pulverization, resulting in shortened adsorbent life. In the process of pressure swing adsorption by rotating wheel, the conventional method is also usedMonolithic adsorbents instead of granular adsorbents, which reduce the alternating stress and loss of adsorbent particles, but provide ammonia stripping and purification H of synthesis ammonia purge gas₂In particular, such regular, especially composite, adsorbents are recently reported at home and abroad.

Disclosure of Invention

The invention provides a new Full Temperature range Simulated rotating Moving pressure swing adsorption (Full Temperature range heated Moving PSA-FTrSRMPSA) process for separating and extracting H from synthetic ammonia purge gas₂And NH₃The method is based on Pressure Swing Adsorption (PSA), and fully utilizes the temperature and pressure of the synthetic ammonia purge gas and the main component H in the raw material gas₂And N₂、CH₄Ar and NH₃The components are in the temperature range of 60-130 ℃, the difference of the adsorption separation coefficient and the physicochemical property in the pressure range of 4.0-7.0 MPa, a middle-high temperature pressure swing adsorption ammonia concentration system and an intermediate gas pressure swing adsorption hydrogen extraction system which are arranged in the centers of an upper multi-channel rotary valve and a lower multi-channel rotary valve and are arranged on a circular ring-shaped rotary tray at the periphery of the multi-channel rotary valve are connected through pipelines and regulate and control the rotation direction and the rotation speed, and a medium-high temperature pressure swing adsorption ammonia concentration system and an intermediate gas pressure swing adsorption hydrogen extraction system which are formed by a mechanism for regulating the rotation direction and the rotation speed of the circular ring-shaped rotary tray, and a compressor, a condensation refrigerator, a heat exchanger, a buffer tank and a process pipeline form a system, so that the gas flowing through the rotary valve channel and the inlet and outlet end of the channel and the pipeline connected with the inlet and outlet end of the adsorption tower on the circular ring-shaped rotary tray and the gas of the adsorption bed layer which rotates and completes the mass transfer of the respective adsorption and desorption steps at the same time through the inlet and outlet position of each adsorption tower and the rotation of each adsorption bed layer, thereby forming a pressure swing adsorption process of a simulated rotary moving bed, realizing the pressure swing adsorption process of the simulated rotary moving bed based on the pressure swing adsorption of the axial flow fixed bed, and leading the multi-step cyclic operation of adsorption and desorption to obtain H with high purity and high yield₂And NH₃The product is returned to the production process of synthetic ammonia for recycling, and the specific scheme is as follows:

extracting H from synthetic ammonia purge gas₂And NH₃The full-temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that the full-temperature range simulated rotary moving bed pressure swing adsorption (FTrSRMPSA) system comprises a medium-high temperature pressure swing adsorption ammonia concentration system (containing a driving mechanism) of n (n is more than or equal to 4 and is less than or equal to 40 natural integers) adsorption towers, a medium-low temperature medium gas pressure swing adsorption system (containing a driving mechanism) of n' (n is more than or equal to 4 and is less than or equal to 40 natural integers) adsorption towers, and H₂Product gas (H)₂PG)/raw material gas (F)/Intermediate Gas (IG)/nitrogen-rich desorption gas (N)₂D) Buffer tank, liquid ammonia product storage tank, raw gas compressor 1/intermediate gas compressor 2, raw gas heat exchange 1 (heating)/ammonia concentrated gas heat exchange 2 (cooling)/condensation freezing and corresponding material and process pipeline, wherein, n middle-high temperature pressure swing adsorption ammonia concentration systems of axial flow fixed composite bed adsorption towers (for short, "n adsorption towers") loaded with various adsorbents and having a certain height-diameter ratio and n ' intermediate gas pressure swing adsorption hydrogen extraction systems of axial flow fixed composite bed adsorption towers (for short, "n ' adsorption towers") loaded with various adsorbents and having a certain height-diameter ratio are respectively and evenly arranged at intervals on an intermediate gas pressure swing adsorption hydrogen extraction system with the rotation speed of omega and n ' adsorption towers₂(n + n ') adsorption towers and corresponding driving mechanisms on a (second/revolution) circular ring-shaped rotating tray, m (m is more than or equal to 5 and less than or equal to 36 natural integers) channels and m' (m is more than or equal to 5 and less than or equal to 36 natural integers) channels are arranged in the center of the circular ring-shaped tray and respectively rotate at the speed of omega₁(seconds/revolution) and ω₁(second/turnover) upper and lower two independently rotating multi-channel rotary valves, the upper multi-channel rotary valve is called as "m-channel rotary valve", the lower multi-channel rotary valve is called as "m ' -channel rotary valve", the inlet and outlet ends of m and m ' channels are respectively connected with the inlet and outlet ends of n adsorption tower/n ' adsorption tower through the pipeline in the circular rotary tray, and connected with H₂The product gas/raw material gas/intermediate gas/nitrogen-rich desorption gas buffer tank and the raw material gas compressor 1/heat exchange 1/intermediate gas compressor 2/ammonia concentrated gas heat exchange 2/ammonia condensing and freezing material and process pipeline are respectively connected with the inlet and outlet of the m/m 'channel rotary valve, the inlet and outlet of the annular rotary tray built-in pipeline and the inlet and outlet of the n/n' adsorption tower, and the process flow is connected with the inlet and outlet of the m/m 'channel rotary valve, the inlet and outlet of the annular rotary tray built-in pipeline and the inlet and outlet of the n/n' adsorption towerThe process is that the synthetic ammonia purge gas from the synthetic ammonia process is used as a raw material gas (F), flows out of a raw material gas buffer tank, is heated or cooled to 60-130 ℃ through a heat exchange 1, directly enters an m-channel rotary valve channel in a medium-high temperature pressure swing adsorption ammonia concentration system or enters an adsorption tower in an n adsorption tower through a built-in pipeline connected with a circular ring-shaped rotary tray to perform medium-high temperature pressure swing adsorption ammonia concentration after being directly or under the pressure of 4.0-7.0 MPa, and is continuously produced from the system and is reversely discharged by rich ammonia (NH)₃D) With ammonia rich flushing of the exhaust gas (NH)₃PW) to form ammonia concentrate gas (NH)₃CG) with the ammonia concentration of more than or equal to 90-95%, cooling to 25-40 ℃ by heat exchange 2, and then entering an ammonia condensation freezing unit, wherein the generated condensate is a liquid ammonia product (NH)₃PL), the concentration is 99.99-99.999%, the yield is 98-99%, the liquid ammonia product tank is input, the produced non-condensable gas enters an Intermediate Gas (IG) buffer tank as low-pressure intermediate gas (LPIG), the non-adsorption phase gas flowing out of the medium-high temperature pressure swing adsorption ammonia concentration system enters the Intermediate Gas (IG) buffer tank as low-pressure intermediate gas (LPIG), and flows out of the buffer tank together with the non-condensable gas as low-pressure intermediate gas (LPIG) and is pressurized to 4.0-7.0 MPa by an Intermediate Gas (IG) compressor 2 to form high-pressure intermediate gas (HPIG) which enters an m 'channel rotary valve channel of the intermediate gas pressure swing adsorption hydrogen extraction system and enters an adsorption tower of an n' adsorption tower to perform intermediate gas pressure swing adsorption hydrogen extraction, and the non-adsorption phase hydrogen product (H) is continuously produced from the system₂PG) with a purity of 99.9 to 99.99% and a yield of 92 to 95%, and nitrogen-rich desorbed gas (N) of an adsorption phase continuously flowing out of the system₂D) Into nitrogen-rich stripping gas (N)₂D) The buffer tank flows out, or is used as fuel gas, or enters the deep cooling nitrogen/argon production and H recovery₂Or in membrane separation to recover H₂Thus, a complete H preparation with high purity and high yield by taking the purge gas of the synthetic ammonia as the raw material gas is formed₂And NH₃The full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) separation and purification process obtains high-purity H with the purity of 99.9-99.99% and the yield of 92-95% from synthetic ammonia₂Product gas (H)₂PG) and purity of more than or equal to 99.99 percent, yieldLiquid ammonia product (NH) with a rate of more than or equal to 98%₃PL), or exported, or returned to the synthetic ammonia manufacturing process for recycling.

Further, the method extracts H from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that the rotation directions of an m and m 'channel rotary valve and a circular rotary tray in a medium-high temperature pressure swing adsorption ammonia concentration system and an intermediate gas pressure swing adsorption hydrogen extraction system and the rotation speeds (omega) of the m and m' channel rotary valve and the circular rotary tray are regulated and controlled by the rotation directions₁、ω₁' and omega₂) The regulation and control between the two are matched, including, 1) synchronous in the same direction, clockwise or anticlockwise rotating in the same direction, and omega₁=ω₁’=ω₂/≠ 0, 2) homodromous, homodromous in the clockwise or counterclockwise direction, and, or ω₁≠0≥ω₁’≠0/ω₂=0, or ω₁≠0≤ω₁’≠0/ω₂=0, or ω₁=ω₁’=0/ω₂Not equal to 0, preferably synchronous and ω₁=ω₁’=ω₂/≠ 0 is asynchronous and omega with syntropy₁≠0≤ω₁’≠0/ω₂=0。

Further, the method extracts H from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that n adsorption towers in the medium-high temperature pressure swing adsorption ammonia concentration system are subjected to adsorption and desorption cycle operation steps of adsorption (A) -average pressure drop (ED)/forward release (PP) -reverse release (D)/flushing (P) -average pressure rise (ER)/waiting area (-) -final charge (FR) in sequence, wherein the pressure equalizing times are up to 4, the pressure equalizing times comprise primary average pressure drop (E1D)/primary average pressure rise (E1R), secondary average pressure drop (E2D)/secondary average pressure rise (E2R), tertiary average pressure drop (E3D)/tertiary average pressure rise (E3R) and quaternary average pressure drop (E4D)/quaternary average pressure rise (E4R), the forward release (PP) and the waiting (-) steps need to be flexibly arranged according to the alternating time sequence of each adsorption tower in the pressure swing adsorption cycle operation process, wherein, the step of sequentially and alternately subjecting the n adsorption towers to the pressure swing adsorption cycle operation is realized by medium-high temperature pressure swingRotation direction of m-channel rotary valve and circular ring-shaped rotary tray in ammonia adsorption concentration system and rotation speed (omega) thereof regulated and controlled₁And omega₂) The regulation and control are matched, and the material and the process gas flowing through the m-channel rotary valve are alternately switched at regular time by each channel in the pressure swing adsorption cycle operation process and enter the n-channel adsorption tower for pressure swing adsorption cycle operation.

Further, the method extracts H from the syngas purge gas₂And NH₃The pressure swing adsorption process of the full-temperature-range simulated rotary moving bed is mainly characterized in that n' adsorption towers in the intermediate gas pressure swing adsorption hydrogen extraction system are subjected to adsorption and desorption cyclic operation steps of adsorption (A) -average pressure drop (ED)/forward release (PP) -reverse release (D)/flushing (P) -average pressure rise (ER)/waiting area (-) -final charge (FR) in turn, wherein the pressure equalizing frequency is up to 4 times, the pressure equalizing frequency comprises primary average pressure drop (E1D)/primary average pressure rise (E1R), secondary average pressure drop (E2D)/secondary average pressure rise (E2R), tertiary average pressure drop (E3D)/tertiary average pressure rise (E3R) and average pressure drop (E4D)/quaternary average pressure rise (E4R), the forward release (PP) and the (-) waiting steps need to be flexibly arranged according to the alternating time sequence of each adsorption tower in the pressure swing adsorption cyclic operation process, wherein, the n ' adsorption towers are alternately subjected to pressure swing adsorption cycle operation steps in turn, namely the m ' channel rotary valve and the circular ring-shaped rotary tray in the intermediate gas pressure swing adsorption hydrogen extraction system rotate in the directions and regulate and control the rotation speeds (omega) of the m ' channel rotary valve and the circular ring-shaped rotary tray₁' and omega₂) The regulation and control are matched, and the material and the process gas flowing through the m 'channel rotary valve are alternately switched at regular time by each channel in the pressure swing adsorption cycle operation process and enter the n' adsorption tower for pressure swing adsorption cycle operation.

Further, one such method is to extract H from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that n adsorption towers in the medium-high temperature pressure swing adsorption ammonia concentration system alternately experience adsorption (A) -Displacement (DP) -average pressure drop (ED)/forward discharge (PP) -reverse discharge (D)/flushing (P) -average pressure rise (ER)/absorption of (-) -final charge (FR) in a waiting areaAdsorption and desorption cycle operation, wherein the displacement gas (DP) is derived from pressurized ammonia concentrate (NH)₃CG), the replacement pressure is equal to the adsorption pressure.

Further, the method extracts H from the syngas purge gas₂And NH₃The full temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that flushing gas (P) of a medium-high temperature pressure swing adsorption ammonia concentration system and an intermediate gas pressure swing adsorption hydrogen extraction system, or cis-bleed gas (PP)/Intermediate Gas (IG) from the system, or H from the outside of the system₂Product gas (H2 PG)/ammonia concentrate gas (NH)₃CG) for batch-wise flushing by rotating one or more openings in the valve channel (channel), the number of openings being at most 4, preferably downstream air (PP) from within the system as flushing gas (P).

Further, the method extracts H from the syngas purge gas₂And NH₃The pressure swing adsorption process of the full-temperature-range simulated rotary moving bed is mainly characterized in that the inverse discharging (D) step of the medium-high-temperature pressure swing adsorption ammonia concentration system and the intermediate gas pressure swing adsorption hydrogen extraction system is used for desorbing by adopting a vacuumizing mode, an additional vacuum pump is connected with a material flow pipeline of a desorbed gas (D) outflow rotary valve or is directly connected with an external pipeline connected with the outlet end of an adsorption tower on a circular rotary tray and is provided with a control valve, and the preferred external pipeline connected with the outlet end of the adsorption tower on the circular rotary tray is directly connected and is provided with a control valve.

Further, the method extracts H from the syngas purge gas₂And NH₃The pressure swing adsorption process of the full-temperature range simulated rotary moving bed is mainly characterized in that final aeration (FR) in the pressure swing adsorption circulation operation of the medium-high temperature pressure swing adsorption ammonia concentration system and the intermediate gas pressure swing adsorption hydrogen extraction system, or raw material gas (F) or Intermediate Gas (IG) or ammonia concentrated gas (NH) from the outside of the system₃CG) or H₂Product gas (H)₂PG) at H₂Product gas (H)₂PG) purity of more than 99.99%, and is preferableBy means of H₂Product gas (H)₂PG) as the final charge (FR) of an intermediate gas pressure swing adsorption hydrogen extraction system.

Further, the method extracts H from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that an n adsorption tower and an n' adsorption tower of a medium-high temperature pressure swing adsorption ammonia concentration and intermediate gas pressure swing adsorption hydrogen extraction system are respectively loaded with various combined adsorbents of active calcium chloride, active carbon and a molecular sieve and various combined adsorbents of aluminum oxide, silica gel, active carbon, the molecular sieve and a carbon molecular sieve.

Further, the method extracts H from the syngas purge gas₂And NH₃The full-temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that the intermediate gas pressure swing adsorption hydrogen extraction system is replaced by a membrane separation hydrogen extraction system, namely, the full-temperature range simulated rotary moving bed pressure swing adsorption (FTrSRMPSA) system comprises a medium-high temperature pressure swing adsorption ammonia concentration system (containing a driving mechanism) and a membrane separation hydrogen extraction system, wherein n (n is more than or equal to 4 and less than or equal to 40 natural integers) adsorption towers, raw material gas enters the medium-high temperature pressure swing adsorption ammonia concentration system, and adsorption phase ammonia concentrated gas (NH) flows out of the system₃CG) is cooled to 25-40 ℃ by the heat exchange 2 and then enters an ammonia condensation refrigeration unit, the non-adsorption phase high-pressure intermediate gas flowing out of the system is cooled to 25-40 ℃ by the heat exchange and then directly enters a membrane separation hydrogen extraction system consisting of multi-stage hydrogen permeable membranes, and H with the purity of more than 99% flows out of the permeation side₂Product gas (H)₂PG), the yield is more than or equal to 95 percent, and the nitrogen-rich gas with high pressure and low pressure flows out from the non-permeable side to enter the second-stage synthesis procedure of the synthetic ammonia production process for recycling.

The invention has the beneficial effects that:

(1) the invention can change the adsorption and desorption cycle operation mode simulation of the traditional full-temperature-range fixed composite bed PSA into the full-temperature-range rotary wheel moving bed PSA process, and obtain the product H with higher efficiency than the rotary wheel PSA of a fixed bed or a typical fan-shaped adsorption chamber₂The purity and the yield of/NH 3 break through the conventional methodThe technical limit of 'inverse relation between purity and yield' of the full-temperature-range fixed adsorption bed layer is limited, the manufacturing complexity and cost of other moving bed PSA processes including a rotating wheel are greatly reduced, and high-purity H is obtained from the adsorption phase and the non-adsorption phase in the PSA separation process in the synthetic ammonia purge gas at the same time in high yield₂Product gas and liquid ammonia product, wherein, H₂The purity of the product gas is 99.9-99.99%, the yield is 92-95%, the purity of the liquid ammonia product is more than or equal to 99.9-99.99%, and the yield is more than or equal to 98%.

(2) The invention adopts the rotation direction and the rotation speed (omega) of the m and m' channel rotary valve and the annular rotary tray of the middle high temperature pressure swing adsorption ammonia concentration system and the middle gas pressure swing adsorption hydrogen extraction system₁/ω₁' and omega₂) The regulation and control are matched, so that the PSA cyclic operation of multi-combination and multi-step adsorption and desorption can be realized on the traditional fixed bed PSA process, and the operation can be flexibly carried out according to the product H₂/NH₃The technical indexes of the technology are required to be adjusted and the existing moving bed PSA technology, such as a multi-channel rotary valve and traditional fixed bed PSA combined technology, a typical sector adsorption chamber rotary wheel PSA or fast wheel PSA moving bed technology and the like, is covered, so that the FTrSRMPSA process using synthetic ammonia purge gas as raw material gas can smoothly, continuously and high-purity and high-yield extract and recover H₂And NH₃The tail gas emission is reduced, and the consumption and the cost of the synthetic ammonia production are further reduced.

(3) The invention greatly reduces the extraction of H from the traditional axial flow fixed bed PSA or FTrPSA₂And NH₃The program control valves and the number of the adjusting valves of the device not only reduce the investment and the cost, but also are suitable for the cyclic operation requirements of the adsorption and the desorption of the high-pressure PSA, the stability and the safety of the operation of the device are also increased, the complexity of the manufacture of the fast-wheel PSA device is reduced, the device can replace foreign import, and the investment and the production cost are further reduced.

(4) The invention adopts the rotation direction and the rotation speed (omega) of the m/m' multi-channel rotary valve and the circular ring-shaped rotary tray₁/ω₁' and omega₂) Regulation and control betweenThe device is matched to adapt to the large fluctuation working condition of the synthetic ammonia purge gas, including the fluctuation of components, concentration, pressure, flow and the like, has large operation flexibility, does not need expensive regular adsorbents required by a rotary wheel or a fast wheel PSA process, and can adopt conventional granular adsorbents to form a composite adsorbent bed.

(5) The invention is based on the raw material gas and the fluctuation working condition thereof and the product H₂/NH₃The requirement of technical index is that the height-diameter ratio of the adsorption tower is adjusted and designed by adjusting the rotation direction and the rotation speed of a multi-channel rotary valve and a circular ring-shaped rotary tray of each subsystem in the process and the matching of the adsorption pressure and the temperature, so that the radial diffusion in the axial flow fixed bed is ignored and the mature mass transfer model of the axial flow fixed bed is met, the axial flow diffusion has smaller and smaller influence along with the acceleration of the rotation speed of the circular ring-shaped rotary tray and the reduction of the height-diameter ratio, and further the mass transfer process in the adsorption tower more approaches the steady-state effect of a moving bed represented by a circulating bed, and H is a steady-state effect₂/NH₃The purity and yield of the product tend to be double high.

(6) The invention replaces the intermediate gas pressure swing adsorption hydrogen extraction system with the traditional multistage membrane separation hydrogen extraction system to form the FTrSRMPSA system, the operating pressure is more stable, and the product H is obtained₂The yield of the process is further improved, simultaneously, the nitrogen-rich desorption gas flowing out from the non-permeation side of the membrane separation hydrogen extraction system can flexibly adjust the pressure and can return to the two-stage process of ammonia synthesis, and the utilization rate of the purge gas reaches 100 percent.

Drawings

FIG. 1 is a schematic flow chart of example 1 of the present invention.

Fig. 2 is a schematic flow chart of embodiment 2 of the present invention.

Fig. 3 is a schematic flow chart of embodiment 3 of the present invention.

Fig. 4 is a schematic flow chart of embodiment 4 of the present invention.

Detailed Description

In order to make those skilled in the art better understand the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention.

Example 1

As shown in FIG. 1, the method for extracting H from the purge gas of synthetic ammonia₂And NH₃The full-temperature-range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) system is formed by arranging a fixed composite bed adsorption tower which is loaded with 5(n '═ 5') axial flows of a molecular sieve and activated carbon and has the height-diameter ratio of 3 and a fixed composite bed adsorption tower which is loaded with 5(n ═ 5) axial flows of aluminum oxide, silica gel, activated carbon and a molecular sieve/carbon molecular sieve and has the height-diameter ratio of 4.5-5.0 on the fixed composite bed adsorption tower at the rotating speed of omega₂An adsorption tower (n '+ n ═ 10) and a corresponding drive mechanism on a circular ring-shaped rotating tray of 0, with the number of channels m' ═ 9 and m ═ 9 respectively, installed in the center of the circular ring-shaped tray, and rotating at a speed of ω respectively₁' 500-700 s and omega₁400-600 s of upper and lower two independently rotating multi-channel rotary valves, a raw material gas (F) pressure stabilizing/compressing machine 1, an Intermediate Gas (IG) compressing machine 2 and an ammonia concentrated gas (NH)₃CG) condensing cooler, heat exchanger, raw gas (F)/Intermediate Gas (IG)/H₂Product gas (H)₂PG)/nitrogen-rich stripping gas (N)₂D) Buffer tank, m/m' channel rotary valve and feed gas (F) and H₂Product gas (H)₂PG), high/low pressure intermediate gas (H/LPIG), product hydrogen/feed gas final charge (H)₂FR of/F), ammonia-rich reverse gas (NH)₃D) With ammonia-containing purge gas (NH)₃PW) to form ammonia concentrate gas (NH)₃CG), non-condensable gas, nitrogen-rich reverse bleed gas (D) to form nitrogen-rich stripping gas (N)₂D) And connecting the inlet and outlet of the rotary valve of the m/m' channel with the hydrogen product gas (H)₂PG), raw material gas (F), high/low pressure intermediate gas (H/LPIG) buffer tank and ammonia concentrated gas (NH)₃CG) condensing cooler and a material pipeline for feeding in and discharging out materials and process gas and a process pipeline connected between an internal pipeline of a circular rotary tray and the upper and lower and upper and lower rotary valves of the two m/m 'channels of the n/n' adsorption tower to form an FTrSRMPSA system, wherein the rotary speed omega of the 9-channel rotary valve (upper) is higher than that of the rotary valve (upper)₁The rotating speed omega of a 9' channel rotary valve (lower) is 400-600 s₁The rotating speed omega of the circular ring-shaped rotating tray is 500-700 s ₂0, purge gas from the synthesis section of synthetic ammonia as feed gas (F), typically comprising 63% (v/v, the same applies hereinafter) of hydrogen (H)₂) 21% nitrogen (N)₂) 6.3% ammonia (NH)₃) 7.1% methane (CH)₄) 1.6% argon (Ar) and 1% others including carbon monoxide (CO) and carbon dioxide (CO)₂) Water (H)₂O) and a trace amount of impurity components including helium (He) and krypton (Kr) flow out of a raw material gas (F) buffer tank, enter a raw material gas (F) channel (such as m ' ═ 1) of a 9 ' channel rotary valve in a medium-high temperature pressure swing adsorption ammonia concentration system after heat exchange is carried out at 1-100-130 ℃, and directly or after pressure regulation is carried out at 4.0-4.2 MPa, and enter a certain adsorption tower (such as n ' ═ 1 ') in an n ' adsorption tower through a pipeline arranged in a circular ring-shaped rotary tray to carry out medium-high temperature pressure swing adsorption ammonia concentration, wherein the adsorption pressure is 4.0-4.2 MPa, the adsorption temperature is 100-130 ℃, and NH in the raw material gas (F) is carried out₃Is concentrated by adsorption as an adsorbate, H₂、N₂Ar and CH₄In order to make the non-adsorption phase gas as Intermediate Gas (IG) flow out from the outlet end of the adsorption tower 1 ' and pass through the process pipeline formed from internal pipeline connected with adsorption tower 1 ', ring-shaped rotary tray and material channel of m ' channel rotary valve (for example m ═ 2 ') through hole, and flow out from outlet end of m ' channel rotary valve, and can be fed into Intermediate Gas (IG) buffer tank and used as raw material gas into some adsorption tower (for example n ═ 1) in the intermediate gas pressure-swing adsorption hydrogen-extracting system, at the same time of making adsorption (A ') step of adsorption tower 1 ', the Intermediate Gas (IG) as raw material gas can be fed into adsorption tower 1 through material pipeline connected with inlet of m channel rotary valve channel through hole (for example m ═ 1) and rotated clockwise along with m channel rotary valve and passed through said channel outlet and connected with internal pipeline of ring-shaped tray and the process pipeline formed from inlet end of adsorption tower 1 to make adsorption tower 1 and make adsorption (A) step of intermediate gas adsorption pressure-swing adsorption hydrogen-extracting system, the adsorption pressure is 4.0-4.2 MPa, and the adsorbate is nitrogen (N)₂) With small amounts of ammonia (NH)₃) With the hydrogen (H) remaining in the dead space in the adsorption tower 2₂) Argon (Ar) and methane (CH)₄) The non-adsorption phase gas flows out from the outlet end of the adsorption tower 1 and passes through the connection with the adsorption towerTower 1, circular ring rotary tray built-in pipeline and process pipeline composed of m-channel rotary valve material channel (such as m 2) through hole, and flowing out from outlet end of m-channel rotary valve as hydrogen product gas (H)₂PG) input hydrogen product gas (H)₂PG) buffer tank, product hydrogen (H)₂PG) of purity of 99.99% or more, pressure of 4.0MPa, or transporting or entering into synthetic ammonia synthesis process for recycling, while the adsorption tower 1 is performing the adsorption (a), the process and material pipeline connecting the m 'channel rotary valve and the adsorption tower 1' finishing the adsorption (a ') step synchronously rotating clockwise along with the m' channel rotary valve to the position of the adsorption tower 2 '(n' ═ 2 ') in fig. 1 to be butted with the adsorption tower 2', so that the adsorption tower 2 'successively enters into the steps of primary uniform pressure drop (E1D') and secondary uniform pressure drop (E2D ') of ammonia concentration adsorption phase and sequential release (PP'), and the generated primary uniform pressure drop gas (E1D ') and secondary pressure drop gas (E2D') successively pass through the common channel (e.g. m '═ 3' and m '═ 4') in the m 'channel rotary valve and the process pipeline connected with the adsorption tower 4' and the corresponding circular ring rotary tray built-in pipeline, equalizing the pressure of an adsorption column 4 '(n' ═ 4 ') in the steps of primary pressure equalization (E1R') and secondary pressure equalization (E2D ') of an ammonia concentrated adsorption phase, reducing the pressure in the adsorption column 2' to 0.3 to 0.4MPa, subsequently passing a purge gas (PP ') generated by the purge (PP') through a common passage (e.g., m '═ 5') in an m '-passage rotary valve and a process pipe connected to the adsorption column 3' through a corresponding pipe provided in a circular rotary tray, purging the adsorption column 3 '(n' ═ 3 ') in the step of purging (P') of the ammonia concentrated adsorption phase, simultaneously with the steps of purging (P ') and releasing (PP') of the ammonia concentrated adsorption phase in the adsorption column 2 ', synchronously rotating clockwise with the m-passage rotary valve to the position of the adsorption column 2(n ═ 2) in FIG. 1, and introducing the adsorption column 2 into a primary pressure drop (E1D') of the nitrogen concentrated adsorption phase, Secondary pressure equalizing and reducing (E2D) and sequential releasing (PP), wherein the generated primary pressure equalizing and reducing gas (E1D) and secondary pressure equalizing and reducing gas (E2D) sequentially flow through a shared channel (such as m is 3 and 4) in an m-channel rotary valve and a process pipeline connected with an adsorption tower 2 and a corresponding annular rotary tray built-in pipeline, and the primary and secondary pressure equalizing and increasing (E1R and E2R) steps in a nitrogen-containing adsorption phase are performedThe pressure in the adsorption column 2 is reduced to 0.3-0.4 MPa, then the forward discharge gas (PP) generated by forward discharge (PP) flows through a common channel (such as m-5) in an m-channel rotary valve and a process pipeline connected with the adsorption column 3 through a corresponding annular rotary tray built-in pipeline, the adsorption column 3 (N-3) in the step of flushing (P) of the nitrogen-containing adsorption phase is flushed, the adsorption column 3 enters the steps of reverse discharge (D) and flushing (P) of the nitrogen-containing adsorption phase along with the clockwise synchronous rotation of the m-channel rotary valve to the position of the adsorption column 3 (N-3) in the figure 1, wherein the reverse discharge gas (D) is used as nitrogen-rich desorption gas (N-4)₂D) The nitrogen-enriched desorption gas (N) flows out from the outlet end of the m-channel rotary valve m-6 channel and enters into the material and process pipeline which is connected with the adsorption tower 3 through the shared channel (such as m-6) in the m-channel rotary valve and the corresponding pipeline arranged in the annular rotary tray₂D) The buffer tank is discharged later, and then the adsorption tower 3 in the washing (P) step is washed (P) with the cis-purge gas (PP) generated from the adsorption tower 2 in the cis-purge (PP) step as the washing gas (P), and the generated nitrogen-containing washing waste gas (N) is discharged₂PW) as low-pressure intermediate gas (LPIG) flows through a pipeline arranged in a circular rotary tray and a flushing waste gas channel (such as m & ltSUB & gt 7 & gt) of an m-channel rotary valve, and enters an Intermediate Gas (IG) buffer tank for recycling after a compressor is pressurized to 4.0-4.2 MPa, the adsorption tower 3 ' enters a reverse releasing (D ') and a flushing (P ') step of an ammonia concentration adsorption phase along with the clockwise rotation of an m ' channel rotary valve to the position of the adsorption tower 3 ' (n ' & ltSUB & gt 3 ') in the figure 1 while the

adsorption towers

2 and 3 containing nitrogen adsorption phases carry out corresponding desorption steps, wherein the ammonia (concentration) reverse releasing gas (NH ') generated by the reverse releasing (D ') is used for generating ammonia-rich (concentration) reverse releasing gas (NH)₃D') as ammonia concentrate gas (NH)₃CG ') flows through a reverse air release channel (such as m' ═ 6 ') in the m' -channel rotary valve and a material and process pipeline connected with a corresponding annular rotary tray built-in pipeline and an adsorption tower 3 ', flows out from an outlet end of the m' -channel rotary valve m '═ 6' channel, enters a condensation refrigeration unit for condensation after heat exchange and cooling, finishes the adsorption tower 3 'in the reverse air release (D') step, enters a flushing (P ') step along with the continuous rotation step of the m' -channel rotary valve, and comes from a forward air release (PP ') flow generated in the forward air release (PP') stepThe adsorption column 3 '(n' ═ 3 ') in the step of flushing (P') the ammonia-concentrated adsorption phase is flushed (P ') through a common passage (e.g., m' ═ 5 ') in the m' -passage rotary valve and a process pipe connected to the adsorption column 3 'through a corresponding pipe built in the annular rotary tray, and the ammonia-rich flush off-gas (NH') produced is flushed₃PW') as ammonia concentrate gas (NH)₃CG ') flows through the shared channel (for example, m' ═ 7 ') in the m' channel rotary valve, the material and process pipeline connected with the corresponding internal pipeline of the circular ring-shaped rotary tray and the adsorption tower 3 'in sequence, flows out from the outlet end of the m' channel rotary valve m 'which is a 7' channel, and is cooled by heat exchange, and then is mixed with the ammonia concentrated gas (NH ') produced in the reverse releasing step (D')₃CG') and condensed in a condensing freezer, wherein the condensate formed by the condensing freezer is a liquid ammonia product (NH) with the ammonia purity of more than or equal to 99.99 percent₃PL), the formed non-condensable gas stream is returned to an Intermediate Gas (IG) buffer tank for recycling after heat exchange and compression, while the adsorption tower 3' performs a desorption step of a corresponding ammonia-containing adsorption phase, the adsorption tower 4 enters a secondary pressure equalization (E2R), a primary pressure equalization (E1R) and a waiting (-) step of a nitrogen-containing adsorption phase with the m-channel rotary valve rotating clockwise to the position of the adsorption tower 4 (n-4) in fig. 1, the adsorption tower 4 performs primary and secondary pressure equalization (E1R and E2R) successively with the adsorption tower 2 in the steps of primary pressure equalization (E1D) and secondary pressure equalization (E2D), the shared channels in the m-channel rotary valves used are m-4 and 3 respectively, after the pressure Equalization (ER) step is finished, the adsorption tower 4 is in waiting time, the empty channel (e.g. m-8) in the corresponding m-channel corresponds to the adsorption tower 4, while the adsorption column 4 is waiting for the second pressure equalization-raising (E1R and E2R) step and the waiting zone (-) at the same time, as the m 'channel rotary valve is rotated clockwise to the position of the adsorption column 4' (n '═ 4') as in fig. 1, the adsorption column 4 'enters the second pressure equalization-raising (E2R') of the adsorption phase containing ammonia, the first pressure equalization-raising (E1R ') and the waiting (-') step, which are successively performed with the adsorption column 2 'in the first pressure equalization-lowering (E1D') and the second pressure equalization-lowering (E2D ') steps, the first and second pressure equalization-raising (E1R' and E2R ') are performed, respectively, with the common channels of the m' channel rotary valve being m 4 'and 3', and after the pressure equalization-raising (ER ') step is finished, the adsorption column 4' is in the waiting stateWhile the (-) time corresponds to the empty passage (e.g. m '═ 8') in the corresponding m 'channel rotary valve, while the adsorption tower 4' is making two pressure equalization-up (E1R 'and E2R;) steps and waiting for the waiting zone (-'), as the m channel rotary valve rotates clockwise to the position of adsorption tower 5(n ═ 5) as shown in fig. 1, the adsorption tower 5 enters the final Filling (FR) step from the hydrogen product gas (H) product gas₂PG) buffer tank product hydrogen (H)₂PG) as final aeration gas (FR), the final aeration gas (FR) flows through a final aeration gas (FR) channel (for example, m is 9) of an m-channel rotary valve and a material and process pipeline which is connected with a corresponding annular rotary tray built-in pipeline and an adsorption tower 5, the final aeration (FR) is carried out on the adsorption tower 5, so that the adsorption pressure in the adsorption tower 5 reaches the adsorption pressure 4.0-4.2 MPa required by the adsorption (A) step, thereby forming the complete nitrogen-containing adsorption phase Pressure Swing Adsorption (PSA) closed loop type cycle operation of the adsorption tower 1, namely, the adsorption (A) -one-time uniform pressure drop (E1D)/two-time uniform pressure drop (E2D)/sequential (PP) -reverse discharge (D)/flushing (P) -two-time uniform pressure rise (E2R)/one-time uniform pressure rise (E1R)/a waiting area (-) -final aeration (FR) step, and then the adsorption tower 1 enters the next closed loop type cycle operation process of adsorption and desorption, the corresponding material gas and process gas entering and exiting the

adsorption towers

2, 3, 4 and 5 are also continuously rotated and alternately switched through the m-channel rotary valve to carry out the corresponding closed-loop circulating operation steps of adsorption and desorption of the material or process gas entering and exiting the adsorption towers through the closed-loop circulating operation process of adsorption and desorption of the adsorption tower 1, and the closed-loop circulating operation step of each adsorption tower in the 5 (n-5) adsorption towers corresponds to the respective closed-loop circulating operation step of the other 4 adsorption towers, so that the hydrogen (H) is continuously produced from the synthetic ammonia purge gas as the feed gas₂) H at a concentration of 99.99% (v/v) or more₂Product gas (H)₂PG)，H₂The gas yield of the product is 92-95% or more, and at the same time, as the m 'channel rotary valve continuously rotates, the final aeration (FR') channel therein steps to the position of the adsorption tower 5 'in fig. 1 and connects the built-in pipeline of the circular ring-shaped rotary tray and the process pipeline of the inlet end of the adsorption tower 5', the adsorption tower 5 'enters the final aeration (FR') step, the raw material gas (F) is used as the final aeration (FR '), and flows through the final aeration (FR') channel (such as the m 'channel rotary valve) of the m' channel rotary valve'9') and the material and process pipelines connected with the corresponding internal pipeline of the circular rotating tray and the adsorption tower 5 ', the adsorption tower 5' is subjected to final charging (FR), so that the adsorption pressure in the adsorption tower 5 reaches the adsorption pressure required by the adsorption (A ') step of 4.0-4.2 MPa, thereby forming the complete closed loop type cycle operation of the nitrogen-containing adsorption phase of the adsorption tower 1', namely, the steps of adsorption (A ') -one time of uniform pressure drop (E1D')/two times of uniform pressure drop (E2D ')/sequential discharge (PP') -reverse discharge (D ')/flushing (P'), -two times of uniform pressure rise (E2R ')/one time of uniform pressure rise (E1R')/waiting zone (-) -final charging (FR '), and then the adsorption tower 1' enters the next closed loop type cycle operation process of adsorption and desorption, the material gas and the process gas which enter and exit the adsorption towers 2 ', 3', 4 'and 5' respectively are continuously rotated through the m 'channel rotary valve to alternately perform closed-loop circulation operation steps of performing corresponding adsorption and desorption on the material or the process gas entering and exiting positions of the adsorption towers respectively in the closed-loop circulation operation process of performing adsorption and desorption on the material or the process gas entering and exiting positions of the adsorption towers 1', and the closed-loop circulation operation step of each adsorption tower in the 5 '(n-5') adsorption towers corresponds to the closed-loop circulation operation step of each other 4 adsorption towers, so that a liquid ammonia product (NH) with the ammonia concentration of more than or equal to 99.99% (v/v) is continuously produced from the synthetic ammonia purge gas serving as the raw material gas₃PL), the yield of the liquid ammonia product is 98-99%. Thereby realizing the simultaneous extraction of H from the gas of the adsorption phase and the non-adsorption phase in the purge gas of the synthetic ammonia₂And NH₃The high purity and high yield 'double high' of the simulated rotating PSA process is carried out on the basis of an axial flow fixed bed layer in the PSA process of the product.

Example 2

As shown in FIG. 2, in example 1, the cyclic operation steps of PSA adsorption and desorption in the medium-high temperature pressure swing adsorption ammonia concentration system were carried out, and the adsorption (A ') step was followed by the replacement (DP') step, and concentrated ammonia gas (NH ') pressurized to the same pressure as that of the adsorption (A') was used₃CG) is used as replacement gas (DP ') to perform replacement (DP'), and after the replacement (DP ') step is completed, the primary average pressure drop (E1D') and the secondary average pressure drop (E2D) are performed') the sequential (PP ') step of the previous example 1 was eliminated, and the corresponding pathway (e.g., m ' =5 ') of the m ' pathway rotary valve was used as the pathway for the displacement gas (DP '), while the displacement exhaust gas (DPW ') from the displacement (DP ') step was generated and passed through the original ammonia-rich purge exhaust gas (NH) in the m ' pathway rotary valve₃PW ') passage (e.g., m ' =7 ') and is used as Intermediate Gas (IG) to enter an Intermediate Gas (IG) buffer tank for cycle use, after finishing the secondary pressure equalizing drop (E2D '), the process enters a reverse releasing (D) step, and then directly enters a waiting step (P), a secondary pressure equalizing step (E2R '), and a primary pressure equalizing step (E1R ') without a flushing step, and finally enters a final charging (FR ') step, whereby the PSA adsorption and desorption cycle operation performed in the medium-high temperature pressure swing adsorption ammonia concentration system is performed by adsorption (A ') -replacement (DP ')/primary pressure equalizing drop (E1D ')/secondary pressure equalizing step (E2D ') -reverse releasing (D '), -)/secondary pressure equalizing step (E2R ')/primary pressure equalizing step (E1R ') -final charging (FR '), and the same purity can be obtained in this embodiment, the yield is close to 99%, and simultaneously, H is enabled₂The yield of the product gas is more than or equal to 94 percent.

Example 3

As shown in figure 3, on the basis of the examples 1 and 2, in the intermediate gas pressure swing adsorption hydrogen extraction system, a vacuum (V) desorption step is adopted to replace a reverse release (D) step of an ammonia concentration adsorption phase, and nitrogen-rich desorption gas (N) formed by vacuum (V) is pumped₂D) Flowing out from N (such as N = 3) adsorption tower outlet, flowing through external pipeline connected with adsorption tower outlet on circular rotary tray, and introducing nitrogen-rich desorption gas (N) after flow control by vacuum pump and control valve arranged on external pipeline₂D) The maximum vacuum degree of the buffer tank is-0.08 MPa, the original reverse-release gas (D) channel (such as m = 6) in the corresponding m-channel rotary valve is changed into an empty channel, the adsorbent in the n adsorption tower is completely desorbed, and the obtained H₂Product gas (H)₂PG) purity is more than or equal to 99.99 percent, yield is more than or equal to 94 percent, and the service life of the adsorbent is further prolonged.

Example 4

As shown in FIG. 4, based on example 1, the method2-stage low-pressure osmotic membrane separation system instead of intermediate gas pressure swing adsorption hydrogen extraction system, raw gas enters a medium-high temperature pressure swing adsorption ammonia concentration system, and adsorption phase ammonia concentrated gas (NH) flows out of the medium-high temperature pressure swing adsorption ammonia concentration system₃CG) is cooled to 25-40 ℃ by heat exchange 2 and then enters an ammonia condensation freezing unit (device), the non-adsorption phase high-pressure intermediate gas flowing out of the system directly enters a membrane separation hydrogen extraction system consisting of 2-level hydrogen permeable hollow fiber membranes after being cooled to 40-60 ℃ by heat exchange, wherein H₂H with the purity of more than 98 percent flows out as a permeate gas component from the permeate side of a primary membrane separation system consisting of 4 groups of membrane modules connected in series₂Product gas (H)₂PG) with pressure of 2.4-2.6 MPa and primary membrane separation pressure difference of 1.4-1.8 MPa, or directly outputting for use, or entering into high-pressure nitrogen-rich second stage of ammonia synthesis process for recycling, and N₂、CH₄Ar is used as an impermeable gas component, flows out from the impermeable side of the primary membrane separation system, enters a secondary membrane separation system formed by connecting 2 groups of membrane components in series, flows out from the permeable side, has the pressure of 1.2-1.4 MPa, and contains 80% of H₂The hydrogen-rich gas directly enters a low-pressure nitrogen-rich secondary section of synthetic ammonia for recycling, or is compressed and pressurized to 4.0-4.2 MPa and then returns to a primary membrane separation system for further recycling an effective component H₂H with a purity of more than 98%₂The yield of the product gas is more than or equal to 96 percent, and the non-permeable gas flowing out from the non-permeable side of the secondary membrane separation system is used as fuel gas.

It will be obvious that the above-described embodiments are only a part, not all, of the embodiments of the present invention. All other embodiments and structural changes that can be made by those skilled in the art without inventive effort based on the embodiments described in the present invention or based on the teaching of the present invention, all technical solutions that are the same or similar to the present invention, are within the scope of the present invention.

Claims

1. Extracting H from synthetic ammonia purge gas₂And NH₃The full temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that the full temperature range simulated rotary moving bed pressure swing adsorption (FTrSR)MPSA) system, comprising a medium-high temperature pressure swing adsorption ammonia concentration system (containing a driving mechanism) with n (n is more than or equal to 4 and less than or equal to 40 natural integers) adsorption towers, a medium-low temperature intermediate gas pressure swing adsorption system (containing a driving mechanism) with n' (n is more than or equal to 4 and less than or equal to 40 natural integers) adsorption towers, H₂Product gas (H)₂PG)/raw material gas (F)/Intermediate Gas (IG)/nitrogen-rich desorption gas (N)₂D) Buffer tank, liquid ammonia product storage tank, raw gas compressor 1/intermediate gas compressor 2, raw gas heat exchange 1 (heating)/ammonia concentrated gas heat exchange 2 (cooling)/condensation freezing and corresponding material and process pipeline, wherein, n middle-high temperature pressure swing adsorption ammonia concentration systems of axial flow fixed composite bed adsorption towers (for short, "n adsorption towers") loaded with various adsorbents and having a certain height-diameter ratio and n ' intermediate gas pressure swing adsorption hydrogen extraction systems of axial flow fixed composite bed adsorption towers (for short, "n ' adsorption towers") loaded with various adsorbents and having a certain height-diameter ratio are respectively and evenly arranged at intervals on an intermediate gas pressure swing adsorption hydrogen extraction system with the rotation speed of omega and n ' adsorption towers₂(n + n ') adsorption towers and corresponding driving mechanisms on a (second/revolution) circular ring-shaped rotating tray, m (m is more than or equal to 5 and less than or equal to 36 natural integers) channels and m' (m is more than or equal to 5 and less than or equal to 36 natural integers) channels are arranged in the center of the circular ring-shaped tray and respectively rotate at the speed of omega₁(seconds/revolution) and ω₁(second/turnover) upper and lower two independently rotating multi-channel rotary valves, the upper multi-channel rotary valve is called m-channel rotary valve for short, the lower multi-channel rotary valve is called m ' channel rotary valve for short, and the inlet and outlet ends of the m and m ' channels are respectively connected with the inlet and outlet ends of the n adsorption tower/n ' adsorption tower through a pipeline built in the circular rotary tray and connected with H₂The product gas/raw material gas/intermediate gas/nitrogen-rich desorption gas buffer tank and the raw material gas compressor 1/heat exchange 1/intermediate gas compressor 2/ammonia concentrated gas heat exchange 2/ammonia condensation frozen material and process pipeline are respectively connected with the inlet and outlet of the m/m 'channel rotary valve, the inlet and outlet of the annular rotary tray built-in pipeline and the inlet and outlet of the n/n' adsorption tower, the process flow is that synthetic ammonia purge gas from the synthetic ammonia process is used as raw material gas (F), flows out of the raw material gas buffer tank and is heated or cooled to 60-130 ℃ through the heat exchange 1, and the temperature of the synthetic ammonia purge gas is controlled to be 60-130 ℃, and the synthetic ammonia purge gas is cooled to be discharged from the raw material gas buffer tankDirectly or after the pressure is regulated to 4.0-7.0 MPa, the ammonia enters an m-channel rotary valve channel in a medium-high temperature pressure swing adsorption ammonia concentration system and is connected with a pipeline arranged in a circular rotary tray, the ammonia enters one of n adsorption towers to perform medium-high temperature pressure swing adsorption ammonia concentration, and ammonia-rich reverse gas (NH) is continuously produced from the system₃D) With ammonia rich flushing of the exhaust gas (NH)₃PW) to form ammonia concentrate gas (NH)₃CG) with the ammonia concentration of more than or equal to 90-95%, cooling to 25-40 ℃ by heat exchange 2, and then entering an ammonia condensation freezing unit, wherein the generated condensate is a liquid ammonia product (NH)₃PL), the concentration is 99.99-99.999%, the yield is 98-99%, the liquid ammonia product tank is input, the produced non-condensable gas enters an Intermediate Gas (IG) buffer tank as low-pressure intermediate gas (LPIG), the non-adsorption phase gas flowing out of the medium-high temperature pressure swing adsorption ammonia concentration system enters the Intermediate Gas (IG) buffer tank as low-pressure intermediate gas (LPIG), and flows out of the buffer tank together with the non-condensable gas as low-pressure intermediate gas (LPIG) and is pressurized to 4.0-7.0 MPa by an Intermediate Gas (IG) compressor 2 to form high-pressure intermediate gas (HPIG) which enters an m 'channel rotary valve channel of the intermediate gas pressure swing adsorption hydrogen extraction system and enters an adsorption tower of an n' adsorption tower to perform intermediate gas pressure swing adsorption hydrogen extraction, and the non-adsorption phase hydrogen product (H) is continuously produced from the system₂PG) with a purity of 99.9 to 99.99% and a yield of 92 to 95%, and nitrogen-rich desorbed gas (N) of an adsorption phase continuously flowing out of the system₂D) Into nitrogen-rich stripping gas (N)₂D) The buffer tank flows out, or is used as fuel gas, or enters the deep cooling nitrogen/argon production and H recovery₂Or enter membrane separation to recover H₂Thus, a complete H preparation with high purity and high yield by taking the purge gas of the synthetic ammonia as the raw material gas is formed₂And NH₃The full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) separation and purification process obtains high-purity H with the purity of 99.9-99.99% and the yield of 92-95% from synthetic ammonia₂Product gas (H)₂PG) and liquid ammonia product (NH) with purity more than or equal to 99.99% and yield more than or equal to 98%₃PL), or exported, or returned to the synthetic ammonia manufacturing process for recycling 1.

2. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that the rotation directions of an m and m 'channel rotary valve and a circular rotary tray in a medium-high temperature pressure swing adsorption ammonia concentration system and an intermediate gas pressure swing adsorption hydrogen extraction system and the rotation speeds (omega) of the m and m' channel rotary valve and the circular rotary tray are regulated and controlled by the rotation directions₁、ω₁' and omega₂) The regulation and control between the two are matched, including, 1) synchronous in the same direction, clockwise or anticlockwise rotating in the same direction, and omega₁=ω₁’=ω₂/≠ 0, 2) homodromous, homodromous in the clockwise or counterclockwise direction, and, or ω₁≠0≥ω₁’≠0/ω₂=0, or ω₁≠0≤ω₁’≠0/ω₂=0, or ω₁=ω₁’=0/ω₂Not equal to 0, preferably synchronous and ω₁=ω₁’=ω₂/≠ 0 is asynchronous and omega with syntropy₁≠0≤ω₁’≠0/ω₂=02。

3. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that n adsorption towers in the medium-high temperature pressure swing adsorption ammonia concentration system are subjected to adsorption and desorption cycle operation steps of adsorption (A) -average pressure drop (ED)/forward release (PP) -reverse release (D)/flushing (P) -average pressure rise (ER)/waiting area (-) -final charge (FR) in sequence, wherein the pressure equalizing times are up to 4, the pressure equalizing times comprise primary average pressure drop (E1D)/primary average pressure rise (E1R), secondary average pressure drop (E2D)/secondary average pressure rise (E2R), tertiary average pressure drop (E3D)/tertiary average pressure rise (E3R) and quaternary average pressure drop (E4D)/quaternary average pressure rise (E4R), the forward release (PP) and the waiting (-) steps need to be flexibly arranged according to the alternating time sequence of each adsorption tower in the pressure swing adsorption cycle operation process, wherein, the n adsorption towers are alternately subjected to pressure swing adsorption circulation operation step through m-channel rotary valves and circles in the medium-high temperature pressure swing adsorption ammonia concentration systemRotating direction of annular rotating tray and its rotation speed (omega) regulated by it₁And omega₂) And each channel in the m-channel rotary valve alternately switches the material and the process gas flowing through the pressure swing adsorption cycle operation process at regular time and enters the n adsorption towers to carry out pressure swing adsorption cycle operation 3.

4. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The pressure swing adsorption process of the full-temperature-range simulated rotary moving bed is mainly characterized in that n' adsorption towers in the intermediate gas pressure swing adsorption hydrogen extraction system are subjected to adsorption and desorption cyclic operation steps of adsorption (A) -average pressure drop (ED)/forward release (PP) -reverse release (D)/flushing (P) -average pressure rise (ER)/waiting area (-) -final charge (FR) in turn, wherein the pressure equalizing frequency is up to 4 times, the pressure equalizing frequency comprises primary average pressure drop (E1D)/primary average pressure rise (E1R), secondary average pressure drop (E2D)/secondary average pressure rise (E2R), tertiary average pressure drop (E3D)/tertiary average pressure rise (E3R) and average pressure drop (E4D)/quaternary average pressure rise (E4R), the forward release (PP) and the (-) waiting steps need to be flexibly arranged according to the alternating time sequence of each adsorption tower in the pressure swing adsorption cyclic operation process, wherein, the n ' adsorption towers are alternately subjected to pressure swing adsorption cycle operation steps in turn, namely the m ' channel rotary valve and the circular ring-shaped rotary tray in the intermediate gas pressure swing adsorption hydrogen extraction system rotate in the directions and regulate and control the rotation speeds (omega) of the m ' channel rotary valve and the circular ring-shaped rotary tray₁' and omega₂) And each channel in the m 'channel rotary valve alternately switches the material and the process gas flowing through the pressure swing adsorption cycle operation process at regular time and enters the n' adsorption tower to carry out the pressure swing adsorption cycle operation 4.

5. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that n adsorption towers in the medium-high temperature pressure swing adsorption ammonia concentration system alternately undergo adsorption (A) -Displacement (DP) -uniform pressure drop (ED)/forward discharge (PP) -reverse discharge (D)/flushing (P) -uniform pressure drop (ED)/reverse discharge (PP) in sequenceAn adsorption and desorption cycle operating step of pressure rise (ER)/wait zone (-) -end charge (FR), wherein the displacement gas (DP) is derived from pressurized ammonia concentrate (NH)₃CG), the replacement pressure equals the adsorption pressure by 5.

6. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that flushing gas (P) of a medium-high temperature pressure swing adsorption ammonia concentration system and an intermediate gas pressure swing adsorption hydrogen extraction system, or cis-bleed gas (PP)/Intermediate Gas (IG) from the system, or H from the outside of the system₂Product gas (H2 PG)/ammonia concentrate gas (NH)₃CG) by rotating one or more openings in the valve channel (channel) up to 4 openings, preferably downstream air (PP) from the system as flushing gas (P) 6.

7. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full-temperature-range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that a middle-high temperature pressure swing adsorption ammonia concentration system and a middle gas pressure swing adsorption hydrogen extraction system are reversely released (D) in a vacuumizing mode, an additional vacuum pump is connected with a material flow pipeline through which desorption gas (D) flows out of a rotary valve, or an external pipeline connected with the outlet end of an adsorption tower on a circular rotary tray is directly connected and is provided with a control valve, and the preferred external pipeline connected with the outlet end of the adsorption tower on the circular rotary tray is directly connected and is provided with a control valve 7.

8. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that final aeration (FR) in the pressure swing adsorption circulation operation of the medium-high temperature pressure swing adsorption ammonia concentration system and the intermediate gas pressure swing adsorption hydrogen extraction system or original air from outside the systemFeed gas (F) or Intermediate Gas (IG) or concentrated ammonia gas (NH)₃CG) or H₂Product gas (H)₂PG) at H₂Product gas (H)₂PG) purity of more than 99.99 percent, and H is preferably adopted₂Product gas (H)₂PG) as the final charge gas (FR) 8 of the intermediate gas pressure swing adsorption hydrogen extraction system.

9. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full-temperature-range simulated rotating moving bed pressure swing adsorption process is mainly characterized in that an n adsorption tower and an n' adsorption tower of a medium-high temperature pressure swing adsorption ammonia concentration and intermediate gas pressure swing adsorption hydrogen extraction system are respectively loaded with various combined adsorbents of active calcium chloride, active carbon and a molecular sieve and various combined adsorbents 9 of aluminum oxide, silica gel, active carbon, the molecular sieve and the carbon molecular sieve.

10. The process of claim 1 wherein the H is extracted from the syngas purge gas₂And NH₃The full-temperature range simulated rotary moving bed pressure swing adsorption process is mainly characterized in that the intermediate gas pressure swing adsorption hydrogen extraction system is replaced by a membrane separation hydrogen extraction system, namely, the full-temperature range simulated rotary moving bed pressure swing adsorption (FTrSRMPSA) system comprises a medium-high temperature pressure swing adsorption ammonia concentration system (containing a driving mechanism) and a membrane separation hydrogen extraction system, wherein n (n is more than or equal to 4 and less than or equal to 40 natural integers) adsorption towers, raw material gas enters the medium-high temperature pressure swing adsorption ammonia concentration system, and adsorption phase ammonia concentrated gas (NH) flows out of the system₃CG) is cooled to 25-40 ℃ by the heat exchange 2 and then enters an ammonia condensation refrigeration unit, the non-adsorption phase high-pressure intermediate gas flowing out of the system is cooled to 25-40 ℃ by the heat exchange and then directly enters a membrane separation hydrogen extraction system consisting of multi-stage hydrogen permeable membranes, and H with the purity of more than 99% flows out of the permeation side₂Product gas (H)₂PG), the yield is more than or equal to 95 percent, and the nitrogen-rich gas with high pressure and low pressure flows out from the non-permeable side and enters the second-stage synthesis procedure of the synthetic ammonia production process for recycling 10.