A full temperature range simulation of air oxygen enrichment process of rotating moving bed pressure swing adsorption FTrSRMPSA

Abstract

The invention discloses an air oxygen enrichment process for full-temperature simulated rotating moving bed pressure swing adsorption, belongs to the technical field of pressure swing adsorption, and solves the technical problem that both the purity and yield of O2 products cannot be achieved. The process places a plurality of axial flow fixed bed adsorption towers on a circular rotating tray and is placed in the center of a multi-channel rotary valve and around the valve, and is connected through pipelines and the rotation direction and speed of the rotary valve, the rotation direction and speed of the circular rotating tray are regulated, so that the gas flowing through the multi-channel rotary valve channel and the pipeline connected to the inlet and outlet ends of the channel and the inlet and outlet ends of the adsorption tower on the circular rotating tray and the rotating and moving adsorption bed in the adsorption tower continuously passes through the position of the inlet and outlet of each adsorption tower and each adsorption bed completes the mass transfer of the respective adsorption and desorption steps while rotating, thereby forming a "simulated rotating moving bed" pressure swing adsorption process, improving the mass transfer efficiency and production scale, and obtaining high-purity and high-yield O2 products.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure swing adsorption (PSA) for separating and preparing oxygen-enriched air, and in particular to the technical field of air separation and oxygen-enriched air using full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA). Background Art

[0002] At present, the main methods for producing oxygen (O2) include cryogenic air distillation (cryogenic air separation), pressure swing adsorption, membrane separation, etc. Among them, the cryogenic air distillation method is mainly suitable for large-scale pure oxygen preparation, and can simultaneously produce high-purity nitrogen (N2) and argon (Ar) byproducts. For small-scale oxygen production devices, its unit oxygen energy consumption is high, the construction investment is large, the oxygen production cost is high, and it is not suitable for oxygen enrichment; the membrane separation method oxygen production process is a separation technology that uses some high molecular polymer fiber materials with selective permeability to O2 or N2 as membrane materials. However, the processing capacity of the membrane separation system is small, the obtained O2 concentration is at most about 50-70%, and the cost is relatively high; the pressure swing adsorption (PSA) method has a simple process flow, the oxygen production process is realized at room temperature and pressure, the device is safe and reliable, the construction investment is low, the unit oxygen energy consumption is low, the degree of automation is high, the number of operators is small, the start-up and shutdown time is short, the adaptability is strong, the oxygen purity can be adjusted arbitrarily between, and the load can be changed arbitrarily within a range. Its disadvantages are that the product is single and the purity and yield are relatively low. However, with the development of specialized oxygen-enriching or oxygen-producing adsorbents, such as the promotion and application of lithium molecular sieves, the purity and yield of oxygen-enriching have been greatly improved. At present, the industry generally uses pressure swing adsorption (PSA) separation method for air separation to produce enriched oxygen. The oxygen-enriched concentration can be as high as 95% (v), and the maximum yield can reach 82-85%.

[0003] Pressure swing adsorption oxygen production mainly includes three types: conventional pressure swing adsorption (PSA), vacuum pressure swing adsorption (VPSA) and atmospheric pressure adsorption (VSA). Among them, conventional PSA is adsorption at a pressure higher than atmospheric pressure (adsorption pressure is 0.2-0.5MPa) and desorption at atmospheric pressure. The advantage is that the unit is simple and the requirement for molecular sieve is low. The disadvantage is that the energy consumption is too high and it is only suitable for small-scale devices (<15t / d); VPSA is adsorption at a pressure slightly higher than atmospheric pressure (adsorption pressure <0.1MPa) and vacuum desorption, with low energy consumption, relatively complex unit, and high investment and cost; VSA is atmospheric pressure adsorption (adsorption pressure <10kPa) and vacuum desorption (desorption pressure is 15-40kPa), with low energy consumption and simple equipment, but high requirement for molecular sieve.

[0004] The adsorption towers used in the pressure swing adsorption (PSA) air separation oxygen enrichment device are mostly fixed beds. Among them, the multi-tower axial flow fixed bed PSA has become the mainstream of small and medium-sized air separation oxygen enrichment. Its main advantages are that it occupies a small area, the larger height-to-diameter ratio brings better dynamic effects, the mass transfer model and design parameters of the fluid in the adsorption tower are relatively mature, the manufacturing is convenient, and the cost is relatively low. However, the resistance of the axial flow fixed bed is relatively large, which in turn limits the selection of the height-to-diameter ratio of the adsorption tower and the adsorption conditions. At the same time, the "contradiction between purity and yield" unique to the axial flow fixed bed still exists. In addition, when the processing scale increases, the increase in the diameter of the adsorption tower is limited by equipment transportation, manufacturing container heads, etc., and the influence of radial diffusion increases. Especially for the relatively low adsorption pressure working conditions such as PSA air separation oxygen enrichment, it can only be dealt with by connecting multiple sets of axial flow fixed bed adsorption towers in parallel, and the investment and land occupation will increase significantly, and the "contradiction between purity and yield" will become more obvious. The biggest advantage of the radial flow fixed bed PSA adsorption tower is that in addition to the small resistance of the adsorption bed, it can adapt to the need of doubling the processing capacity by simply increasing the length of the adsorption tower (cylinder), especially for low-pressure atmospheric air separation units. As the scale of air separation oxygen-enriched units increases significantly, the application of radial flow fixed bed PSA technology also expands. However, the biggest disadvantage of the radial flow fixed bed is that the flow of gas in the bed is much more complicated than that of the axial flow fixed bed. The adsorbent particles in the bed are easily fluidized due to uneven air flow disturbances, which reduces the mass transfer efficiency. For this reason, the radial flow fixed bed generally needs to add an air flow distributor to make the gas in the adsorption bed evenly distributed, which has become one of the most core technical means of the radial flow fixed bed PSA separation process. However, it is precisely because of the need for gas distribution that the structure of the radial flow fixed bed adsorption tower has more non-adsorption space than the structure of the axial flow fixed bed adsorption tower, making the "contradiction between purity and yield" of PSA particularly prominent. In addition, radial flow fixed bed adsorption towers are only suitable for large-scale air separation oxygen production or air separation purification due to their complex internal structure, high manufacturing difficulty, and high material consumption. The existing axial flow or radial flow fixed bed pressure swing adsorption (PSA) oxygen enrichment process does not have as many adsorption towers, valves, and complex automatic control as PSA hydrogen production. However, due to the low operating pressure and short cycle time of the oxygen production device, very strict requirements are placed on the adsorption bed with low resistance drop, uniform airflow distribution, fast opening and closing, long-life valves, and reasonably matched pumps. In addition to developing more effective adsorbents, innovative process design is needed to expand its application range and reduce production costs, especially how to more effectively overcome the "contradiction between purity and yield" and further improve oxygen enrichment in air separation oxygen enrichment devices of different sizes to reflect sufficient technical and economic benefits.

[0005] In order to overcome some defects of the fixed-bed pressure swing adsorption oxygen enrichment process, a PSA radial flow rotor adsorption (RWPSA) process has been developed for air separation oxygen enrichment at home and abroad. That is, the adsorbent is fixed in the adsorption container and does not make relative movement, but the adsorbent is rotated as a whole through the belt action of the driving mechanism, and the positions of the logistics (gas) including air feed gas, reverse exhaust gas, pressurized gas, etc. entering and exiting the rotary adsorber are fixed. The adsorption and desorption cycle operations are carried out simultaneously in each adsorption fan-shaped chamber in different adsorbers, which makes up for the defects of the classic moving bed adsorption process that the adsorbent is easy to consume and cannot be applied to the PSA separation or purification process. At the same time, compared with the traditional fixed-bed PSA process, the adsorbent loading amount is greatly reduced, the adsorption efficiency is improved, the purity and yield of the product gas are improved, and to a certain extent, the technical bottleneck of "the contradiction between purity and yield" existing in the fixed-bed PSA process is broken through. However, the RWPSA process also has obvious limitations and disadvantages: First, the diameter and height (thickness) of the adsorption rotor are greatly limited, resulting in insufficient adsorption treatment scale. This is because RWPSA is essentially a moving bed. To achieve the "steady-state" mass transfer of typical moving bed adsorption processes such as circulating beds or fluidized beds, its axial mass transfer diffusion or radial mass transfer diffusion capacity must be limited. This feature is an advantage for axial flow or radial flow fixed bed processes; second, the manufacturing of the rotor PSA equipment is complex, especially the equipment with equalization, and the number of equalization times does not exceed 2 times. At present, most of them are manufactured or monopolized by foreign companies, and the cost is relatively high; third, it is more suitable for the rapid adsorption and rapid desorption of a single adsorbent component and the adsorption mechanism of the adsorbent component is mainly kinetic adsorption, such as the purification of VOCs exhaust gas. For the adsorption mechanism of air separation oxygen enrichment, it is usually dominated by equilibrium adsorption, so this RWPSA process is not very suitable. When the air contains more impurity components such as CO2, water and hydrocarbons, the adsorbent in the RWPSA process cannot form a composite bed such as a fixed bed filled with multiple adsorbents for treatment, and is particularly susceptible to damage by water droplets and other easily contaminated droplets in the air; Fourth, the adsorbent in the RWPSA is prone to being thrown off due to the presence of shear force during rotation, resulting in biased flow or short flow of the process flow gas in the adsorption bed, which greatly reduces the mass transfer efficiency and makes the adsorbent more easily pulverized, resulting in a shortened service life of the adsorbent. For example, application number US09584269 discloses this type of modular rotary pressure swing adsorption device, including a rotary valve and an adsorption stator and a rotor (rotary valve group) rotatably connected to the stator; the stator includes a first stator valve surface, a second stator valve surface, a plurality of first functional cavities connected to the first stator valve surface, and a plurality of second functional cavities connected to the second stator valve surface; the rotor includes a first rotor valve surface connected to the first stator valve surface, a second rotor valve surface connected to the second stator valve surface, and a plurality of flow channels therein for receiving the adsorbent.Each flow channel includes a pair of opposite ends, and a plurality of holes arranged in the surface of the rotor valve and connected to the end of the flow channel and the functional opening so that each flow channel periodically presents a plurality of discontinuous pressure levels between high pressure and low pressure, and the airflow flowing through the first and second functional chambers remains uniform. The patented device can be configured so that the fluid flows through the adsorber component in a radial, axial or inclined conical direction relative to the rotor axis. In order to work at a high cycle frequency, the advantage of radial flow is that the centripetal acceleration will be parallel to the flow channel so that the buoyancy-driven free convection is the most stable, and the centrifugal clamping of the granular adsorbent has a uniform flow distribution. The defects of this patent are that it is susceptible to damage by water droplets and other easily contaminated droplets in the air, and the rapid cycle causes the adsorption pressure vessel and the adsorbent to bear greater alternating stress. The existing RWPSA air separation oxygen enrichment process realizes secondary pressure equalization and can separate medium-purity oxygen (O2) from the air, reaching 70-85%. Its cycle steps include adsorption, pressure equalization, inversion, vacuuming / flushing, pressurization, etc., and the adsorption pressure is less than or equal to 1.8-2.0×10. 5 Pa. In the above-mentioned rotary pressure swing adsorption method, a regular adsorbent is often used to replace a granular adsorbent, which can reduce the alternating stress and loss of the adsorbent, but it is also difficult to solve the defects of the rotary pressure swing adsorption process. Summary of the invention

[0006] In view of some problems of the various existing fixed bed and rotary PSA air separation oxygen enrichment processes mentioned above, the present invention proposes a new full temperature range simulated rotating moving pressure swing adsorption (Full Temperature range Simulated Rotated Moving PSA - FTrSRMPSA) process for PSA air separation oxygen enrichment. The process is based on axial flow fixed bed pressure swing adsorption (PSA), and multiple axial flow fixed bed adsorption towers are placed in the center of a multi-channel rotary valve and arranged on a circular rotating tray around it, and are connected through pipelines and the rotation direction and rotation speed (ω1) of the rotary valve, and the rotation direction and rotation speed (ω2) of the circular rotating tray are regulated, so that the gas flowing through the multi-channel rotary valve channel and the pipeline connected to the inlet and outlet ends of the channel and the inlet and outlet ends of the adsorption tower on the circular rotating tray, and the rotating and moving adsorption bed in the adsorption tower, while continuously passing in and out of each adsorption The positions of the tower inlet and outlet and each adsorption bed layer completes the mass transfer of their own adsorption and desorption steps while rotating, thereby forming a "simulated rotating moving bed" pressure swing adsorption process, realizing a simulated rotating moving bed pressure swing adsorption process based on axial flow fixed bed pressure swing adsorption, making the multi-step cyclic operation of adsorption and desorption, while achieving "double high" yield and purity and avoiding deep adsorption, suitable for the corresponding flow rate, component concentration, pressure or temperature fluctuation conditions of air as the raw gas, making full use of the various advantages of axial flow fixed bed pressure swing adsorption, rotating wheel adsorption and simulated moving bed, overcoming the defects of these existing technical processes, the specific scheme is as follows:

[0007] A full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) air separation oxygen enrichment process, the full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) system is composed of n (3≤n≤20 natural integer) axial flow fixed bed adsorption towers loaded with one or more adsorbents and arranged on an adsorption tower with a rotation speed (ω2, seconds (s) as the unit) of a circular rotating tray, and m (5≤m≤36 A FTrSRMPSA system is formed by a multi-channel rotary valve having a natural integer of channels and arranged in the center of a circular rotating tray to rotate at a rotation speed (ω1, in seconds (s)), a material pipeline for the multi-channel rotary valve and material gas outside the system to enter and exit, and a process pipeline connected to the upper and lower adsorption towers and the multi-channel rotary valve through the built-in pipeline of the circular rotating tray, and a corresponding driving mechanism for driving the rotation direction of the circular rotating tray and the multi-channel rotary valve and regulating its rotation speed (ω1 and ω2), a buffer tank, a vacuum pump / or a booster, and the pipeline connecting the inlet and outlet of the adsorption tower and the inlet and outlet of the m-channel rotary valve is connected through the built-in pipeline preset in the circular rotating tray to form a process pipeline and is the same as the number of channels m of the m-channel rotary valve, and the position of the material gas entering and exiting the FTrSRMPSA system is fixed by allocating the channels of the m-channel rotary valve to rotate, and the material gas includes air as raw material gas (F), O2 product gas (O2PG), flushing gas (P) outside the system, final inflation gas (FR) outside the system, and reverse discharge (D) gas or / and vacuum air (V) Or / and the desorption gas (D) composed of flushing waste gas (PW), and correspondingly connected to equipment including buffer tank (device), booster / vacuum pump, circulation pump, etc., the position of process gas flow in the process pipeline connected by the built-in pipeline in the circular rotating tray between the inlet and outlet of the m-channel rotary valve and the inlet and outlet of the adsorption tower is moving and changing. The process gas flows in the FTrSRMPSA system, including raw gas (F), forward discharge gas (PP), flushing gas (P) inside and outside the system, pressure-equalizing gas (ED), reverse discharge gas (D) gas or / and vacuum gas (V) or / and the desorption gas (D) composed of flushing waste gas (PW), pressure-equalizing gas (ER), final charging (FR) and product oxygen (O2PG). The specific adsorption and desorption cycle process is from FTrSRMPSA The raw gas air (F) outside the system enters the raw gas (F) inlet of the m-channel rotary valve, and enters from the bottom of the adsorption tower for adsorption (A) through the raw gas (F) channel and outlet of the m-channel rotary valve, the built-in pipeline of the annular rotating tray, and the process pipeline connected to the inlet of one or more axial flow fixed bed adsorption towers in the adsorption state on the corresponding annular rotating tray. After the rotation direction and rotation speed (ω1) of the m-channel rotary valve and the rotation direction and rotation speed (ω2) of the annular rotating tray are regulated and matched continuously, the non-adsorbed phase gas flowing out from the top of the adsorption tower just enters the O2 product gas (O2PG) channel of the m-channel rotary valve through the process pipeline.The O2 product gas (O2PG) flows out from the m-channel rotary valve O2 product gas (O2PG) channel to form O2 product gas (O2PG) and enters the O2 product gas buffer tank for output. After the adsorption tower in the adsorption state completes the adsorption (A) step, the m-channel rotary valve and the circular rotating tray continue to rotate and step, or / and the adsorption (A) step. The adsorption tower that has finished performs forward discharge (PP) or equal pressure drop (ED) on another or several adsorption towers in the flushing (P) or equal pressure increase (ER) state through the process pipeline in the system. The adsorption tower that has finished the forward discharge (PP) or equal pressure drop (ED) step enters the reverse discharge (D) or / and vacuum pumping (V) or / and flushing (P) step as the m-channel rotary valve and the annular rotating tray continuously rotate and step. The desorbed gas (D) formed by the reverse discharge gas (D) or / and vacuum pumping air (V) or / and flushing waste gas (PW) flowing out of the adsorption tower, or flows through the internal or external pipeline of the annular rotating tray and the reverse discharge gas (D) / vacuum pumping air (V) / flushing waste gas (PW) channel of the m-channel rotary valve and its outlet end and flows through the desorbed gas (D) buffer tank, or is directly discharged, or enters the nitrogen (N2) recovery process, and the reverse discharge (D) or / and vacuum pumping (V) is finished. or / and the adsorption tower in the flushing (P) step, as the m-channel rotary valve and the annular rotary tray continuously rotate and step, it enters the equalizing pressure rising (ER) or / and the waiting area (-) step, flows out from the adsorption tower in the equalizing pressure dropping (ED) step and enters the adsorption tower in the equalizing pressure rising (ER) step through the built-in pipeline of the annular rotary tray and the equalizing pressure dropping gas (ED) channel of the m-channel rotary valve for equalizing pressure, so that the pressure in the adsorption tower in the equalizing pressure rising (ER) step is equal to the pressure in the adsorption tower in the equalizing pressure dropping (ED) step, and ends the equalizing pressure rising (ER) or / and the waiting area (-) step of the adsorption tower, as the m-channel rotary valve and the annular rotary tray further rotate continuously, it enters the final charging (FR) step, and the O2 product gas (O2PG) or raw air (F) as the final charging gas (FR) flows through the m-channel rotary valve final charging gas (FR) The channels and the built-in pipelines of the annular rotating tray enter the adsorption tower for pressurization until the pressure in the adsorption tower reaches the adsorption pressure required for the adsorption (A) step, and prepare for the next round of adsorption and desorption cycle operation, wherein each adsorption tower performs one step or multiple steps and each step is performed by regulating and matching the rotation direction and rotation speed (ω1) of the rotary valve with the rotation direction and rotation speed (ω2) of the annular rotating tray, so that the timing table of the cyclic operation of adsorption and desorption of the m channels in the rotating m-channel rotary valve and the n adsorption towers in the rotating annular rotating tray is connected end to end into a circle, and the operational cyclicity of the pressure swing adsorption (PSA) adsorption and desorption process is completely formed, and all the material gases and process gases are evenly and alternately distributed in the m circular channels of the m-channel rotary valve in the system and the built-in pipelines in the annular rotating tray and each adsorption tower,The pressure swing adsorption (PSA) of a cycle is carried out simultaneously through the rotating rotary valve (ω1) and the adsorption tower on the corresponding rotating annular rotating tray (ω2). The position of the process gas entering and leaving the adsorption tower is constantly changed by matching the rotation direction and rotation speed (ω1) of the rotary valve with the rotation direction and rotation speed (ω2) of the annular rotating tray, so that each adsorption tower repeats the adsorption and desorption steps, which is equivalent to each fixed bed adsorption tower completing its own adsorption and desorption steps while the m-channel rotary valve and the annular rotating tray rotate, thereby forming a "simulated rotating moving bed" pressure swing adsorption process, thereby, the product O2 obtained from the air has a purity of 85-95% and a yield of 85-95%.

[0008] Furthermore, in the process of the full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA), the rotation direction of the m-channel rotary valve and the annular rotating tray and the regulation and matching between the rotation speeds (ω1 and ω2) thereof include: 1) synchronous in the same direction, rotating in the same direction in a clockwise or counterclockwise direction, and ω1=ω2 / ≠0; 2) asynchronous in the same direction, rotating in the same direction in a clockwise or counterclockwise direction, and ω1>ω2 or ω1<ω2 or ω1≠0 / ω2=0 or ω1=0 / ω2≠0 , 3) heterodyne synchronization, heterodyne rotation in clockwise / counterclockwise or counterclockwise / clockwise, and ω1=ω2 / ≠0, 4) heterodyne asynchrony, heterodyne rotation in clockwise / counterclockwise or counterclockwise / clockwise, and ω1>ω2 or ω1<ω2 or ω1≠0 / ω2=0 or ω1=0 / ω2≠0, preferably, unidirectional synchronization, unidirectional rotation in clockwise or counterclockwise direction, and ω1=ω2 / ≠0, and unidirectional asynchrony, unidirectional rotation in clockwise or counterclockwise direction, and ω1<ω2 or ω1≠0 / ω2=0.

[0009] Furthermore, the air separation oxygen enrichment process of the full-temperature simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) described herein, the combination of the closed cycle operation steps of adsorption and desorption of the full-temperature simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) described herein also includes, 1 to 2 times of pressure equalization, 1 to 2 batches of flushing, 1 time of vacuuming, 1 to 2 times of heating and cooling heat exchange temperature swing adsorption, 1 time of sequential placement and pressure drop equalization sequence offset, 1 to 2 waiting areas, 1 time of replacement desorption step, and the number of adsorption towers (n) and the corresponding number of channels (n) of the m-channel rotary valve are increased, the height-to-diameter ratio of the adsorption tower is reduced, and the rotation speed of the m-channel rotary valve or the annular rotating tray is fast enough or the rotation cycle is short enough, the effect of air separation and purification is infinitely close to the "steady-state" mass transfer separation and purification effect of the moving bed, and finally the purity of the O2 product gas (O2PG) is equal to 95%, and the product gas yield is equal to 95%.

[0010] Furthermore, in the air separation oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA), the air (F) as a raw material has a temperature of 10 to 60°C, a pressure of atmospheric pressure to 0.6 MPa, and a flow rate of 100 to 20,000 Nm 3 / h.

[0011] Furthermore, in the air separation oxygen-enriched process of the full-temperature simulation rotating moving bed pressure swing adsorption (FTrSRMPSA), the average pressure drop (ED) and the average pressure rise (ER) have a maximum number of 2 and a minimum number of 1, and the adsorption operating pressure range is 0.2 to 0.6 MPa.

[0012] Furthermore, in the air separation oxygen-enriched process of a full-temperature simulated rotating moving bed pressure swing adsorption (FTrSRMPSA), the flushing gas (P) comes from the vent gas (PP) in the system, or from the O2 product gas (O2PG) outside the system, and is flushed in batches through one or more openings in the channel (groove) of the m-channel rotary valve, and the number of openings is at most 3. Preferably, the vent gas (PP) from the system is used as the flushing gas (P), and the yield of the O2 product gas (O2PG) exceeds 90%.

[0013] Furthermore, in the air separation oxygen-enriched process of a full-temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA), the inversion (D) step adopts a vacuum method for desorption, and the additional vacuum pump is either connected to the logistics pipeline of the desorbed gas (D) flowing out of the m-channel rotary valve, or directly connected to the external pipeline connected to the outlet end of the adsorption tower on the annular rotating tray and a control valve is provided on the external pipeline, preferably directly connected to the external pipeline connected to the outlet end of the adsorption tower on the annular rotating tray and a control valve is provided on the external pipeline.

[0014] Furthermore, in the air separation oxygen-enriched process of the full-temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA), the final charge (FR) comes from the air raw material (F) or O2 product gas (O2PG) outside the system. When the purity of the O2 product gas (O2PG) is greater than or equal to 90%, the O2 product gas (O2PG) is preferably used as the final charge (FR).

[0015] The beneficial effects of the present invention are:

[0016] 1. Through the present invention, the adsorption and desorption cycle operation mode of the traditional fixed composite bed PSA can be simulated into a full-temperature rotary wheel moving bed PSA process, so as to obtain the purity and yield of the O2 product with higher efficiency than the fixed bed or the typical fan-shaped adsorption chamber rotary wheel PSA, breaking through the technical limitation of "the purity and yield are inversely proportional" of the conventional and fixed adsorption beds, and greatly reducing the complexity and cost of the rotary wheel PSA process and equipment manufacturing, so that the purity of the O2 product gas is 85-95%, and the yield is 85-95%.

[0017] 2. The present invention can realize multi-combination and multi-step adsorption and desorption PSA cycle operation on the traditional fixed bed PSA process by regulating and matching the rotation direction and rotation speed (ω1 and ω2) of the multi-channel rotary valve and the annular rotating tray, thereby solving the limitation problems of low operating pressure and short cycle time of traditional axial flow and radial flow fixed bed PSA oxygen production devices, and strict requirements on adsorption beds with low resistance drop and uniform airflow distribution, fast opening and closing, and long-life valves. It can also be flexibly adjusted according to the technical indicators and operating conditions of O2 products, and covers three typical axial flow or radial flow fixed bed PSA processes, namely pressure swing adsorption (PSA), vacuum pressure swing adsorption (VPSA) and atmospheric adsorption (VSA), as well as existing moving bed PSA processes such as moving bed processes of typical fan-shaped adsorption chamber rotating wheel PSA or fast wheel PSA.

[0018] 3. The present invention greatly reduces the number of program-controlled valves and regulating valves in the traditional fixed-bed PSA air separation oxygen-enrichment device, and can replace the gas flow distributor (plate / disc) which is one of the core components in the air separation oxygen-enrichment equipment, and reduce the adsorbent loading amount, so that the height-to-diameter ratio of the axial flow fixed bed is further reduced. At the same time, it also reduces the complexity of manufacturing radial flow fixed-bed PSA and fast-wheel PSA devices and can replace foreign imports, further reducing investment and production costs.

[0019] 4. The present invention adapts to large fluctuations in air feed gas, including fluctuations in components, concentrations, pressure, flow, etc., by regulating and matching the rotation direction and rotation speed (ω1 and ω2) of the multi-channel rotary valve and the annular rotating tray. It has greater operational flexibility and does not require expensive regular adsorbents required by the rotary wheel PSA process. Conventional granular adsorbents can be used to form a composite adsorbent bed.

[0020] 5. The present invention adopts measures such as adjusting the rotation speed ω1 of the multi-channel rotary valve and the rotation speed ω2 of the annular rotating tray, opening through holes in the annular channels of the multi-channel rotary valve and a common channel for process gases, so that the air separation oxygen-enriched system originally based on equilibrium adsorption is transformed into a kinetic adsorption mechanism, which plays a greater role, realizes a multi-step and multi-cycle process of adsorption and desorption, thereby improving the production capacity of a unit adsorbent or a single adsorption tower, and breaking the defect of the number of channels being limited in the manufacturing process of conventional multi-channel rotary valves, further improving the mass transfer efficiency and production scale, and obtaining a "double high" O2 product with high purity and high yield.

[0021] 6. The present invention adjusts and designs the height-to-diameter ratio of the adsorption tower according to the requirements of the air raw material and its fluctuating operating conditions and the technical indicators of the product O2 by adjusting the rotation direction of the multi-channel rotary valve and the annular rotating tray and the matching of the rotation speeds ω1 and ω2 as well as the adsorption pressure and temperature, so that the radial diffusion in the axial flow fixed bed is negligible and the mature mass transfer model of the axial flow fixed bed is satisfied. The influence of the axial flow diffusion becomes smaller and smaller as ω2 increases and the height-to-diameter ratio decreases, thereby making the mass transfer process in the adsorption tower closer to the "steady-state" effect of a moving bed represented by a circulating bed, and the purity and yield of the O2 product tend to be closer to the "double high" of the theoretical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the process of Example 1 of the present invention.

[0023] Figure 2 This is a schematic diagram of the process of Example 2 of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention.

[0025] Example 1

[0026] like Figure 1As shown, a full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) air separation oxygen enrichment process, wherein the full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) system is composed of three axial flow fixed bed adsorption towers with a height-to-diameter ratio of 2 to 3 and loaded with a composite adsorbent composed of activated alumina, 13X and LiX, which are placed in a rotating speed of ω2= An adsorption tower (n=3) on a circular rotating tray with a rotation speed of 100 to 300 s and a corresponding driving mechanism, an 11-channel rotary valve with m channels (m=11) and arranged in the center of the circular tray with a rotation speed of ω1=(20 to 60 s), an air raw gas (F) / desorbed gas (D) blower 1 / 2, a vacuum pump, an external pipeline directly connected to the vacuum pump at the bottom of the circular rotating tray adsorption tower, the 11-channel rotary valve and a material pipeline for the inlet and outlet of material gases composed of raw gas (F), product gas (PG), desorbed gas (D), replacement gas (DP) and final charging gas (FR), and a process pipeline connected to the upper and lower adsorption towers and the 11-channel rotary valve through the internal pipeline of the circular rotating tray, a buffer tank for product gas (PG) / desorbed gas (D) / raw gas (F), and a desorbed gas (D) buffer tank connected to a desorbed gas (D) blower 2 and a temperature swing adsorption (TSA) The purification device is composed of a FTrSRMPSA system, in which the rotation speed ω1 of the 11-channel rotary valve is 20-60s, the rotation speed ω2 of the annular rotary tray is 100-300s, and the rotation direction of both is clockwise. The 11 channels in the rotary valve are provided with 3 through holes, and the functions of the channels are as follows: 2 channels supply air raw gas (F), 2 channels supply oxygen (O2) product gas (O2PG), 2 channels supply replacement gas (DP), 1 channel supplies replacement waste gas (DPW), and 1 channel is used as a common pressure-equalizing drop gas (ED) One channel is used for common supply of forward venting (PP) as flushing gas (P) and vacuum flushing (VP), one channel is used for reverse venting (D) as desorption gas (D), and one channel is used for common supply of air raw gas (F) and displacement waste gas (DPW) as final charging gas (FR). The displacement waste gas (DPW), O2 product gas (O2PG) and desorption gas (D) material pipelines flowing out of the outlet of the 11-channel rotary valve are connected to the air raw gas (F), O2 product gas (O2PG) and desorption gas (D) respectively. The product gas (O2PG) and the desorption gas (D) buffer tank are connected, the vacuum pump is connected to the external pipeline directly connected to the end of the vacuum gas (V) flowing out of the adsorption tower and is connected to the desorption gas (D) buffer tank as the desorption gas (D), the desorption gas (D) buffer tank is respectively connected to the desorption gas (D) discharge pipe and a desorption gas (D) blower 2 and a temperature swing adsorption (TSA) purification device inlet gas end, the purified gas flowing out of the purification device is used as the replacement gas (DP) and is connected to the replacement gas (DP) inlet end of the 11-channel rotary valve. The specific process is that the raw material gas is ambient air, which is pressurized to 0.1~0.2MPa, from the material channel of the rotary valve raw material gas (F) connected to the material pipeline of the inlet through hole of the 11-channel rotary valve channel, such as m=1 and 2, wherein, channel 1 and channel 2 are switched at regular intervals as the 11-channel rotary valve rotates clockwise and the rotation speed ω1 is coordinated with the clockwise rotation and rotation speed ω2 of the annular rotating tray to be used as material channels, ensuring that the adsorption tower 1 in the adsorption (A) state continuously feeds and discharges materials, and enters the adsorption tower 1 through the outlet of the through hole of channel 1 / 2 connected to the built-in pipeline of the annular rotating tray and the process pipeline formed by the inlet end of the adsorption tower 1 and performs the adsorption (A) step, wherein oxygen (O2) and argon (Ar) in the air, as non-adsorbed phase gases, flow out from the outlet end of the adsorption tower 1 and pass through the process pipeline connected to the adsorption tower 1, the built-in pipeline of the annular rotating tray and the material channel of the 11-channel rotary valve (such as m=3 or 4) a process pipeline composed of through holes, oxygen (O2) purity of 85-95% (v / v) oxygen-enriched product gas (O2PG) flows out from the product gas (PG) material pipeline connected to the rotary valve and the product buffer tank, enters the oxygen-enriched product gas (O2PG) buffer tank or is directly transported to the outside, nitrogen (N2), a small amount of water (H2O), carbon dioxide (CO2), hydrocarbons (CnHm) and residual oxygen (O2) in the air adsorbed by the adsorption tower 1, after the adsorption (A) step of the adsorption tower 1 is completed, as the 11-channel rotary valve and the annular rotating tray rotate synchronously in the clockwise direction, the adsorption tower 1 enters the displacement (DP) step of the desorption process, the atmospheric pressure desorbed gas (D) from the desorbed gas (D) buffer tank is pressurized to the adsorption pressure (0.1-0.2MPa) by the blower 2, and then purified by the desorbed gas (D) temperature swing adsorption (TSA) device to remove water (H2O) and carbon dioxide (CO2) therein The purified desorbed gas (D) (mainly nitrogen (N2)) with impurities such as hydrocarbons (CnHm) is used as the replacement gas (DP) and enters the adsorption tower 1 through the 11-channel rotary valve material pipeline (such as m=5 / 6) and the process pipeline in the system for replacement (DP). The replacement pressure and replacement temperature are the same as the adsorption pressure and adsorption temperature of the adsorption (A) step. The replacement waste gas (DPW) generated in the replacement (DP) step enters the raw gas (F) buffer tank through the material pipeline connecting the adsorption tower 1 and the 11-channel rotary valve (such as m=7) and the material pipeline, and is used together with the raw gas (F) as the final charging gas (FR) of the adsorption tower 3 in the final charging (FR) pressurization step. The adsorption tower 1 and the corresponding material channel and process channel that have completed the replacement (DP) step rotate synchronously with the 11-channel rotary valve and the annular rotating tray to the position as shown in FIG. Figure 1The position of the adsorption tower 2 in the middle enters the steps of pressure drop (ED), forward release (PP) and reverse release (D). The pressure drop (ED) is first performed from the adsorption tower 1. The process gas of the pressure drop (ED) generated flows through the built-in pipeline connecting the annular rotating tray and the process pipeline of the 11-channel rotary valve and the common channel of the rotary valve (such as m=8), and is pressure-equalized with the adsorption tower 3 in the pressure rise (ER) step. After the pressure drop (ED) step is completed, the adsorption tower 1 is further released (PP). The forward release gas (PP) generated flows through the built-in pipeline connecting the annular rotating tray and the process pipeline of the rotary valve and the common channel of the rotary valve (such as m=9) and is used as the flushing gas (P) to flush the vacuum (VP) after the waiting area is finished. The adsorption tower 3 of the step is vacuum flushed (P), and then the adsorption tower 1 is reversed (D) and vacuumed (V), wherein the reversed degassing gas (D) generated is discharged from the rotary valve as a desorbed gas flow through the built-in pipeline connecting the annular rotating tray and the rotary valve process pipeline and the rotary valve channel (such as m=10) and enters the desorbed gas (D) buffer tank for standby or discharge, and the desorbed gas (D) generated by vacuuming (V) enters the desorbed gas (D) buffer tank through an external pipeline connected to the bottom of the annular rotating tray adsorption tower directly connected to an external vacuum pump. At this time, the adsorption tower 1 is in a vacuum state, and the adsorption tower 1 and the corresponding material channel and process channel of the equal pressure drop (ED) / forward release (PP) / reverse release (D) / vacuuming (V) steps are completed. The 11-channel rotary valve and the annular rotating tray are synchronously rotated to the following state. Figure 1The position of the adsorption tower 3 in the middle enters the waiting (-), vacuum flushing (VP), equal pressure rise (ER) and final filling (FR) steps. The discharge gas (PP) from the adsorption tower 2 in the discharge (PP) step is used as the flushing gas (P) to perform vacuum flushing (P) on the adsorption tower 1 in the vacuum flushing (VP) through the common channel (such as m=9) of the 11-channel rotary valve and the process pipeline connected thereto. The flushing waste gas (PW) generated is As the desorbed gas (D), it flows through the inner pipeline connecting the annular rotating tray, the rotary valve process pipeline and the rotary valve channel (e.g., m=10), is discharged from the 11-channel rotary valve and enters the desorbed gas (D) buffer tank. The pressure-equalizing gas (ED) flowing out of the adsorption tower 1 which has completed the flushing (P) step and the adsorption tower 2 which is in the pressure-equalizing step (ED) passing through a waiting area (-) is pressure-equalizing (ER) through the 11-channel rotary valve common channel (e.g., m=8) and the process pipeline in the system, so that the pressure of the adsorption tower 2 and the adsorption tower 1 is 0.05-0.08MPa on average. The pressure-equalizing step (ER) of the adsorption tower 1 is completed. , the replacement waste gas (DPW) from the raw gas buffer tank and the newly added raw gas (F) are used as the final charging (FR) and enter the adsorption tower 1 through the final charging channel of the 11-channel rotary valve (such as m=11) and the corresponding process pipeline for final charging (FR), so that the pressure in the adsorption tower 1 reaches the pressure of 0.1-0.2MPa required for the adsorption (A) step, thereby forming a complete and multi-step pressure swing adsorption (PSA) closed-loop cycle operation of the adsorption tower 1, that is, adsorption (A) / displacement (DP)-equal pressure drop (ED) / forward discharge (PP) / reverse discharge (D) / vacuuming (V)-vacuum flushing (VP) / wait (-) / pressure rise (ER) / final filling (FR) steps, and then the adsorption tower 1 enters the next closed-loop cycle operation process of adsorption and desorption, and the corresponding material gas and process gas entering and exiting the adsorption towers 2 and 3 are also continuously matched and rotated by the annular rotating tray and the 11-channel rotary valve to alternately switch the material or / and process gas inlet and outlet positions of each adsorption tower during the closed-loop cycle operation process of adsorption and desorption in the adsorption tower 1 to perform the corresponding closed-loop cycle operation steps of adsorption and desorption. The closed-loop cycle operation steps of each adsorption tower correspond to the closed-loop cycle operation steps of the other two adsorption towers. Thus, oxygen-rich (O2) product gas (O2PG) is continuously produced from ambient air as raw material gas, with a purity of 92-95% (v / v) and a product gas yield of 92-95%. At the same time, the replacement waste gas (DPW) returns to the raw material gas (buffer tank) as flushing gas (P), and a part of the desorbed gas (D) that has been purified is used as replacement gas (DP) The recycling method greatly reduces energy consumption and desorbed gas emissions, and realizes the "double highs" of high purity and high yield of the simulated rotating PSA process based on the axial flow fixed bed layer in the process of purifying air to prepare oxygen-enriched PSA.

[0027] This embodiment adopts measures such as alternately switching the two raw gas / product gas / replacement gas channels of the 11-channel rotary valve, using a common channel and opening three through holes in the channel, and adjusting the rotary valve speed ω1 (=20-60s) and the annular rotating tray speed ω2 (=100-300s). In the adsorption and desorption cycle operation with only three adsorption towers, a replacement (DP) step of purifying the desorbed gas (D) as the replacement gas (DP), using the vented gas (PP) as the vacuum flushing gas (P), and replacing the waste gas (DPW) and the raw gas (F) as the final charging gas (FR) are added. The operation of multiple steps is completed in one adsorption tower, so that the adsorption mass transfer in the cyclic operation of adsorption and desorption reaches a relatively ideal "steady state", overcomes the defects of the longer axial mass transfer path depending on the equilibrium adsorption mechanism and other obstacles, and obtains the "double high" of the oxygen-enriched product gas, thereby obtaining a higher oxygen-enriched purity and yield than the traditional vacuum pressure swing adsorption (VPSA) process consisting of three fixed bed adsorption towers.

[0028] Example 2

[0029] like Figure 2As shown, a full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) air separation oxygen enrichment process, wherein the full temperature range simulated rotating moving bed pressure swing adsorption (FTrSRMPSA) system is composed of five axial flow fixed bed adsorption towers with a height-to-diameter ratio of 3 and loaded with a composite adsorbent composed of alumina, 13X and LiX supported on carbon fibers (CNFs) and evenly spaced on a stationary annular rotating tray with a rotation speed of ω2=0s. The adsorption tower (n=5) has 9 A FTrSRMPSA system is formed by a 9-channel rotary valve (m=9) channels and arranged in the center of a circular rotating tray, which rotates at a rotation speed (ω1=60-200s), a material pipeline for the rotary valve and the material gas outside the system to enter and exit, and a process pipeline connected to the upper and lower adsorption towers and the 9-channel rotary valve through the built-in pipeline of the circular rotating tray, as well as a corresponding driving mechanism for driving the rotation direction of the circular rotating tray and the 9-channel rotary valve and regulating its rotation speed (ω1 and ω2), a buffer tank and a compressor. The air raw material is pressurized to 0.6-0.8MPa by the compressor and then enters the FTrSRMPSA system, wherein the rotation speed ω2 of the circular rotating tray in the system is adjusted to 0, that is, it does not rotate, and the rotation direction of the 9-channel rotary valve is still clockwise, and its rotation speed ω1 is 60-200s. The positions of the 5 adsorption towers are fixed, but the 9-channel rotary valve is regularly rotated clockwise in steps so that each adsorption tower undergoes adsorption (A)- The adsorption and desorption cycle operation steps are as follows: primary pressure drop (E1D) / secondary pressure drop (E2D) / forward discharge (PP)-reverse discharge (D) / flushing (P)-secondary pressure rise (E2R) / primary pressure rise (E1R) / waiting (-)-final filling (FR), wherein the flushing gas (P) comes from the forward discharge gas (PP) in the system, and the flushing waste gas (PW) and the reverse discharge gas (D) are used as the desorption gas (D). The pressure in the adsorption tower at the end of the primary pressure drop (E1D) / primary pressure rise (E1R) step is 0.2-0.3MPa, and the pressure in the adsorption tower at the end of the secondary pressure drop (E2D) / secondary pressure rise (E2R) step is 0.1MPa, the 9 channels in the 9-channel rotary valve are used as follows: 1 channel (such as m=1) supplies air raw gas (F), 1 channel (such as m=2) supplies O2 product gas (O2PG), 1 channel (such as m=3) supplies primary pressure drop (E1D) and corresponding primary pressure rise (E1R), 1 channel (such as m=4) supplies secondary pressure drop (E2D) and corresponding secondary pressure rise (E2R), 1 channel (such as m=5) supplies forward venting (PP) and corresponding flushing gas (P), 1 channel (such as m=6) supplies reverse venting (D) as desorption gas (D), 1 channel (such as m=7) supplies waste gas (PW) as desorption gas (D), 1 channel (such as m=8) is used for isolation, and 1 channel (such as m=9) is used for flushing waste gas (PW). O2 product gas (O2PG) is used as the final filling (FR). All material gases and process gases are evenly and alternately distributed in the 9 circular channels of the 9-channel rotary valve in the system, the built-in pipes in the annular rotating tray and each adsorption tower, and a cycle of pressure swing adsorption (PSA) is carried out simultaneously through the rotating 9-channel rotary valve (ω1) and the 5 adsorption towers on the corresponding static annular rotating tray (ω2=0). The position of the process gas entering and leaving each adsorption tower is determined by the rotation direction of the 9-channel rotary valve and the The rotation speed (ω1) changes continuously, so that each adsorption tower repeats the adsorption and desorption steps, which is equivalent to each fixed bed adsorption tower completing its own adsorption and desorption steps during the rotation of the 9-channel rotary valve without rotating, thus forming a "simulated rotating moving bed" pressure swing adsorption process, that is, PSA5-1-2P operation mode, 5 towers, one tower is always in the adsorption step, 2 times of equalization, atmospheric pressure flushing and desorption, thus, the oxygen-rich (O2) product gas (O2PG) obtained from the ambient air has a purity of 85-92% and a yield of 85-88%. .

[0030] Compared with Example 1, this embodiment eliminates the vacuum pump, TSA purification device and other equipment in the system of Example 1, adds two adsorption towers and a compressor, and changes the original 11-channel rotary valve to a 9-channel rotary valve. However, the annular rotating tray of this case does not rotate. Instead, the 9-channel rotary valve rotates clockwise to perform a "simulated rotating moving bed" operation on the five axial flow fixed bed adsorption towers. The effect is naturally not as good as that of Example 1. However, this case is operated at a pressure of 0.6 to 0.8 MPa, making full use of two pressure equalizations and forward venting as flushing gas, and eliminating the energy consumption of vacuuming and TSA purification equipment and annular rotating tray driving. Therefore, the energy consumption of this case is basically equivalent to or slightly lower than that of Example 1, and the actual production cost is low. Moreover, the oxygen enrichment concentration and yield of this case are much higher than those of the traditional fixed bed PSA5-1-2P air separation oxygen enrichment process.

[0031] Example 3

[0032] like Figure 2As shown, on the basis of Examples 1 and 2, the air feed gas is pressurized to 0.6-0.8 MPa and then enters the FTrSRMPSA system, wherein the rotation speed ω1 of the 9-channel rotary valve in the system is adjusted to be the same as the rotation speed ω2 of the annular rotating tray in Example 1, that is, ω1=ω2=100-300s, and the rotation direction of the 9-channel rotary valve and the rotation direction of the annular rotating tray are both clockwise, that is, the control mode between the rotation direction of the rotary valve and the annular rotating tray and the rotation speed of the 9-channel is synchronous in the same direction, and the 9-channel rotary valve and the annular rotating tray rotate synchronously in the same direction step by step so that each adsorption tower undergoes adsorption (A)-primary average pressure drop (E1D) / secondary average pressure drop (E2D) / forward release (PP)-reverse release (D) / flushing (P) - secondary pressure rise (E2R) / primary pressure rise (E1R) / waiting (-) - final charge (FR) adsorption and desorption cycle operation steps, wherein the flushing gas (P) comes from the forward discharge gas (PP) in the system, the flushing waste gas (PW) and the reverse discharge gas (D) are used as the desorption gas (D), the pressure in the adsorption tower after the primary pressure drop (E1D) / primary pressure rise (E1R) steps are 0.2-0.3MPa, and the pressure in the adsorption tower after the secondary pressure drop (E2D) / secondary pressure rise (E2R) steps are 0.1MPa, the 9 channels in the 9-channel rotary valve are used as follows: 1 channel (such as m=1) supplies air raw gas (F), 1 channel (such as m=2) supplies O2 product gas (O2PG), 1 channel (such as m=3) supplies primary pressure drop (E1D) and corresponding primary pressure rise (E1R), 1 channel (such as m=4) supplies secondary pressure drop (E2D) and corresponding secondary pressure rise (E2R), 1 channel (such as m=5) supplies forward discharge gas (PP) and corresponding flushing gas (P), 1 channel (such as m=6) supplies desorption gas (D ) for reverse venting (D), 1 channel (such as m=7) for desorption gas (D) flushing waste gas (PW), 1 channel (such as m=8) for isolation, and 1 channel (such as m=9) for O2 product gas (O2PG) for final filling (FR). All material gases and process gases are evenly and alternately distributed in the 9 circular channels of the rotary valve in the system and the built-in pipes in the annular rotating tray and each adsorption tower, and a cycle of pressure swing adsorption (PSA) is transferred through the rotating 9-channel rotary valve (ω1) and the connected annular rotary valve rotating in the same direction. The adsorption towers on the rotating tray (ω2=ω1) perform various steps of the adsorption and desorption process simultaneously. The position of the process gas entering and leaving the adsorption tower is constantly changed by the rotation direction and rotation speed (ω1) of the 9-channel rotary valve and the rotation direction and rotation speed (ω2) of the annular rotating tray, so that each adsorption tower repeats the adsorption and desorption steps, which is equivalent to each fixed bed adsorption tower completing its own adsorption and desorption steps as the 9-channel rotary valve and the annular rotating tray rotate synchronously in the same direction, thereby forming a "simulated rotating moving bed" rotary wheel / fast wheel pressure swing adsorption ( PSA5-1-2P, that is, 5 towers-1 tower adsorption-2 times equalization pressure-flushing desorption) process, thus, the product O2 obtained from the ambient air has a purity greater than or equal to 92%, and its yield is 92%. Its adsorbent loading is reduced by nearly 40-50% compared with the axial flow fixed bed PSA5-1-2P process with the same height-diameter ratio and processing volume, the number of program control valves and regulating valves is reduced by 90%, saving 40-50% of investment and operating costs, the processing volume is increased by nearly 1 times, and the process operation stability is greatly improved. Compared with Example 2, although Example 3 has the same PSA adsorption and desorption cycle steps as Example 2, the processing volume of Example 3 is increased by nearly 30-40% compared with the working condition of Example 2. At the same time, it not only overcomes the limitations of the traditional fan-shaped adsorption chamber (mainly radial flow) rotor PSA with a small height-diameter ratio and uneven airflow distribution, as well as the single adsorbent and easy shear force throwing resulting in a short service life of the adsorbent, but also breaks through the limitations of foreign companies' fast-wheel PSA equipment complexity, expensive regular adsorbents and technology monopoly, replacing imports. .

Claims

1. An air oxygen enrichment process for full-temperature simulated rotating moving bed pressure swing adsorption FTrSRMPSA, wherein the full-temperature simulated rotating moving bed pressure swing adsorption system is composed of n axial flow fixed bed adsorption towers loaded with one or more adsorbents and arranged on an annular rotating tray with a rotation speed ω2, a multi-channel rotary valve with m channels and arranged in the center of the annular rotating tray and rotating at a rotation speed ω1, a material pipeline for the multi-channel rotary valve and the material gas outside the system to enter and exit, and a process pipeline connected to the upper and lower adsorption towers and the multi-channel rotary valve through the built-in pipeline of the annular tray, and a corresponding driving mechanism for driving the rotation direction of the annular rotating tray and the multi-channel rotary valve and regulating their rotation speeds ω1 and ω2, a buffer tank, a vacuum pump / or a booster to form a FTrSRMPSA system, characterized in that: The pipeline connecting the inlet and outlet of the adsorption tower and the inlet and outlet of the m-channel rotary valve is connected through the built-in pipeline preset in the circular rotating tray to form a process pipeline and is the same as the number of channels m of the m-channel rotary valve. The position of the material gas entering and exiting the FTrSRMPSA system is fixed by allocating the channel of the m-channel rotary valve. The material gas includes air as raw gas, O2 product gas, flushing gas outside the system, final inflation outside the system, and desorption gas composed of reverse venting or / and vacuum air or / and flushing waste gas, and is correspondingly connected to equipment including a buffer tank, a booster / vacuum pump, and a circulating pump. The position of the process gas flow in the process pipeline connected between the inlet and outlet of the m-channel rotary valve and the inlet and outlet of the adsorption tower through the built-in pipeline in the circular rotating tray is The position is moving and changing, and the process gas flows in the FTrSRMPSA system, including raw gas, forward discharge gas, flushing gas inside and outside the system, equalized pressure reduction gas, reverse discharge gas or / and desorption gas composed of vacuum air or / and flushing waste gas, equalized pressure increase gas, final inflation and product oxygen. The specific adsorption and desorption cycle process is that the raw gas air from outside the FTrSRMPSA system enters the raw gas inlet of the m-channel rotary valve, and passes through the raw gas channel and outlet of the m-channel rotary valve, the built-in pipeline of the annular rotating tray and the process pipeline connected to the inlet of one or more axial flow fixed bed adsorption towers in the adsorption state on the annular rotating tray, and enters from the bottom of the adsorption tower for adsorption, and passes through the m-channel rotary valve. The rotation direction and rotation speed ω1 are connected to The regulation and matching between the rotation direction and the rotation speed ω2 of the annular rotating tray are continuously stepped, and the non-adsorbed phase gas flowing out from the top of the adsorption tower just enters the O2 product gas channel of the m-channel rotary valve through the process pipeline, and flows out from the O2 product gas channel of the m-channel rotary valve to form O2 product gas, and then enters the O2 product gas buffer tank for output. After the adsorption step is completed, the adsorption tower in the adsorption state continues to rotate and step with the m-channel rotary valve and the annular rotating tray, or / and the adsorption tower that has finished adsorption performs sequential release or equal pressure drop on another or several adsorption towers in the flushing or equal pressure increase state through the process pipeline in the system. The adsorption tower that has finished the sequential release or equal pressure drop step enters the reverse direction as the m-channel rotary valve and the annular rotating tray continue to rotate and step. The desorbed gas formed by the reverse degassing or / and vacuuming or / and flushing waste gas flowing out of the adsorption tower may flow through the internal or external pipeline of the annular rotating tray and the reverse degassing / vacuuming / flushing waste gas channel of the m-channel rotary valve and its outlet end and flow through the desorbed gas buffer tank, or be directly discharged, or enter the nitrogen recovery process, and the adsorption tower that ends the reverse degassing or / and vacuuming or / and flushing step may enter the pressure equalization or / and waiting area step as the m-channel rotary valve and the annular rotating tray continuously rotate and step, and may flow out from the adsorption tower in the pressure equalization step and enter the pressure equalization step through the internal pipeline of the annular rotating tray and the pressure equalization gas channel of the m-channel rotary valve to equalize the pressure.The pressure in the adsorption tower in the equalizing pressure raising step is made equal to the pressure in the adsorption tower in the equalizing pressure dropping step, and the equalizing pressure raising or / and waiting area step of the adsorption tower is terminated. As the m-channel rotary valve and the annular rotating tray further rotate continuously, the final charging step is entered, and the O2 product gas or raw air flows as the final charging flow through the final charging channel of the m-channel rotary valve and the built-in pipeline of the annular rotating tray into the adsorption tower for pressurization until the pressure in the adsorption tower reaches the adsorption pressure required for the adsorption step, and prepares for the next round of adsorption and desorption cycle operation, wherein each adsorption tower performs one step or multiple steps and each step is performed by regulating and matching the rotation direction and rotation speed ω1 of the rotary valve with the rotation direction and rotation speed ω2 of the annular rotating tray, so that the timing table of the cyclic operation of adsorption and desorption of the m channels in the rotating m-channel rotary valve and the n adsorption towers in the rotating annular rotating tray is connected end to end into a circle, and a pressure swing adsorption is completely formed. The operation cycle of the adsorption and desorption process is that all the material gases and process gases are evenly and alternately distributed in the m circular channels of the m-channel rotary valve in the system, the built-in pipes in the annular rotating tray and each adsorption tower, and the pressure swing adsorption of a cycle is carried out simultaneously through the rotating rotary valve ω1 and the adsorption tower on the corresponding rotating annular rotating tray ω2. The position of the process gas entering and leaving the adsorption tower is constantly changed by matching the rotation direction and rotation speed ω1 of the rotary valve with the rotation direction and rotation speed ω2 of the annular rotating tray, so that each adsorption tower repeats the adsorption and desorption steps, which is equivalent to each fixed bed adsorption tower completing its own adsorption and desorption steps while the m-channel rotary valve and the annular rotating tray rotate, thereby forming a "simulated rotating moving bed" pressure swing adsorption process. As a result, the product O2 obtained from the air has a purity greater than or equal to 85~95%, and a yield greater than or equal to 85~95%.

2. The air oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption FTrSRMPSA according to claim 1, characterized in that: The combination of closed-cycle operation steps of adsorption and desorption of the full-temperature simulation rotating moving bed pressure swing adsorption also includes 1 to 2 times of pressure equalization, 1 to 2 batch flushing, 1 time of vacuuming, 1 to 2 times of heating and cooling heat exchange temperature swing pressure swing adsorption, 1 time of staggered sequence of sequential release and pressure drop equalization, 1 to 2 waiting areas, and 1 replacement desorption step. In addition, the number of adsorption towers n and the corresponding number of channels n of the m-channel rotary valve are increased, the height-to-diameter ratio of the adsorption tower is reduced, and the rotation speed of the m-channel rotary valve or the annular rotating tray is fast enough or the rotation cycle is short enough. The effect of air separation and purification is infinitely close to the "steady-state" mass transfer separation and purification effect of the moving bed, and the purity of the O2 product gas is finally obtained to be equal to 95%, and the product gas yield is equal to 95%.

3. The air oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption FTrSRMPSA according to claim 1, characterized in that: The air used as raw material has a temperature of 10~60℃, a pressure of normal pressure to 0.6MPa, and a flow rate of 100~20,000Nm 3 / h.

4. The air oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption FTrSRMPSA according to claim 1, characterized in that: The maximum number of the average pressure drop and the average pressure rise is 2, the minimum number is 1, and the adsorption operation pressure range is 0.2~0.6MPa.

5. The air oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption FTrSRMPSA according to claim 1, characterized in that: The flushing gas comes from the downstream exhaust gas in the system, or from the O2 product gas outside the system, and is flushed in batches through one or more openings in the channel of the m-channel rotary valve, and the number of openings is at most 3.

6. The air oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption FTrSRMPSA according to claim 1, characterized in that: The reverse placement step adopts a vacuuming method for desorption, and the additional vacuum pump is either connected to the logistics pipeline of the desorbed gas outflowing the m-channel rotary valve, or directly connected to the external pipeline connected to the outlet end of the adsorption tower on the annular rotating tray and a control valve is provided on the external pipeline.

7. The air oxygen enrichment process of the full temperature range simulated rotating moving bed pressure swing adsorption FTrSRMPSA according to claim 1, characterized in that: The final inflation gas comes from the air raw material or O2 product gas outside the system.

Images