Parallel flow heat regenerative fluidized bed adsorption system with adsorbent and method of operation

Abstract

An adsorption / desorption system is configured to adsorb a certain proportion of feed gas into an adsorbent to produce treated gas and used adsorbent, and then desorb 90% to 100% of the feed gas from the used adsorbent to produce desorbed gas, clean adsorbent, and desorbed products; the adsorption / desorption system includes an adsorption circuit and a desorption circuit, wherein: - the adsorption circuit includes a multi-stage adsorption vessel having multiple vertically separated adsorber stages, such that each stage is configured as an independent bubbling fluidized bed operating as an adsorbent; - the desorption circuit includes A desorption container includes a desorption stage configured to operate as a fluidized bed in a rapid fluid or gas lift / transport mode; and the desorption stage is configured to use a desorption gas as a fluidizing gas and heat transfer medium to regenerate the used adsorbent; such that the desorption gas is a gas from which the used adsorbent is desorbed to produce clean adsorbent, the desorption product is a certain proportion of the desorption gas removed from the desorption loop as a product stream, and when the adsorption / desorption system is in a steady state, the clean adsorbent is up to 100% of the adsorbent entering the adsorption container.

Description

Technical Field

[0001] This invention relates to a multi-stage fluidized bed adsorption unit with a thermal desorption unit. The used adsorbent material is transported to the thermal desorption unit via a co-current gas elevator or a rapid fluidized bed using exhaust gas from the desorption unit. Background Technology

[0002] The removal of contaminants from fluid streams using adsorbents is often carried out as part of industrial processes. For example, adsorbing carbon dioxide, hydrocarbons, nitrogen, etc., from gas streams.

[0003] For economic reasons, adsorbent materials are usually regenerated, and the most common regeneration method is: - Pressure swing adsorption, in which adsorption typically occurs at a higher pressure than desorption; - Temperature-switched adsorption, where adsorption occurs at a lower temperature than desorption, and - Variable concentration adsorption, in which adsorption is carried out using a gas stream to be treated with a high concentration of pollutant gas, and regeneration is carried out using a stripping gas stream with a low concentration of pollutant gas.

[0004] Many designs described in early patents utilize a moving bed of adsorbent that falls down the column and reacts with the inlet gas stream moving upwards. This configuration leverages countercurrent flow to improve adsorption. These designs typically have a desorption section, either within the same column or externally, to recover the adsorbent for reuse. To return the recycled adsorbent, some configurations use mechanical lifting devices (screw or bucket elevators are common) to transfer the adsorbent (regenerated or unregenerated) from the base of the column back to the top. These lifting devices can physically decompose the adsorbent.

[0005] To mitigate some of the problems associated with the use of mechanical lifting devices, some configurations have used gas lifting, such as in US 2,550,955 (Berg), where gas from the top of the tower is pressurized and then used as the lifting gas to return the regenerated adsorbent from the base of the tower to the top.

[0006] US 2,921,970 (Gilmore) discloses a moving bed desorption / adsorption apparatus providing continuous countercurrent desorption / adsorption. The desorbed gas from the adsorbent is cooled in a heat exchanger 21, which is used to heat the eluent gas. This eluent gas is further heated and separated, with a portion used in the desorption section and the remainder used as a lift gas to transport the used adsorbent to the desorption section. As the lift gas portion moves the adsorbent to the upper part of the apparatus, it replaces a certain proportion of heavier alkanes in the adsorbent. The eluent gas is a straight-chain hydrocarbon with fewer carbon atoms than the lowest molecular weight straight-chain hydrocarbon in the feed, and therefore initially requires the addition of this eluent gas. Since the eluent is circulated through the process in a steady state, the eluent gas is separated in a fractionation column for reuse. The system uses an eluent gas that is easily separated from the desired fraction by fractionation and partial condensation.

[0007] US 2,891,902 (Hess et al.) includes a moving bed adsorber that regenerates the adsorbent by using a booster gas as a stripping gas without requiring an upper desorption section. Similar to Gilmore, Hess et al. requires that the stripping / transport gas be readily separable from the desorbed straight-chain hydrocarbons, as this is an important recovery stream. Both Hess et al. and Gilmore use a hot stripping / elution gas that can be readily separated from the desorbed material.

[0008] US 4,047,906 (Murakami et al.) relates to a fluidized bed adsorption process that uses carbon spheres to avoid the use of particulate adsorbents, which are pulverized during use. Murakami et al. used activated carbon spheres with a diameter of 0.2 mm to 2.0 mm, with a preferred average diameter of about 0.7 mm.

[0009] US 4,319,892 (Waghorne et al.) discloses an adsorption process for recovering hydrogen from a feed gas or vapor. Waghorne et al. used a magnetic field to stabilize a series of vertically spaced fluidized beds, including both desorption and adsorption beds, with a special adsorption section at the base. In this special section at the base, the amount of hydrogen bound to the adsorbent is reduced by using a proportion of the adsorbed gas recovery stream (hydrocarbon product). The hydrocarbon recirculation stream flow rate in the special section is adjusted to maintain a high concentration of hydrocarbons in the special section, such that the downward-moving adsorbent retains virtually no hydrogen. The hydrocarbon product stream is removed from the top of the process vessel, cooled, and passed through a separation tank to remove water. The separation tank removes liquid from the gas stream, therefore it must operate below the dew point of the substance to be removed (in this case, water). When the adsorbent entering the lower special section is cooled by the cooling section and the recirculated hydrocarbon stream has left the separation tank, the temperature of the adsorbent and the recirculated hydrocarbon stream is below 200°F, i.e., below the desorption temperature of the adsorbent. The recycled hydrocarbon stream is then used to transport the adsorbent to the upper portion of the process vessel, where it enters a heated desorption zone, thereby regenerating the adsorbent for reuse. Waghorne et al. aimed to avoid using multiple fluidized beds within a section, as this introduces unnecessary complexity and has hindered the widespread adoption of fluidized bed adsorption. Furthermore, Waghorne et al. suggested that the favorable heat transfer and isothermal conditions within a fluidized bed are actually detrimental to the adsorption process, and these disadvantages were overcome by using magnetic stabilization.

[0010] US 8,353,978 (Knaebel) describes a moving bed design aimed at reducing shear stress on the adsorbent to minimize wear. Knaebel emphasizes that adsorbent wear is a significant issue in moving bed adsorbent design, and to overcome this deficiency, the inventors propose using multiple perforated trays to reduce shear stress on the adsorbent. The adsorbent moves through the perforations, and the stress experienced by the adsorbent particles is reduced when the adsorber operates with a slow, counter-current piston flow. Knaebel emphasizes that it is this slow piston flow above many closely spaced plates that distinguishes it from previous configurations. Knaebel also proposes a fixed bed with valves to guide the gas and mimic a moving bed, thus completely eliminating downward flow. Knaebel regenerates the adsorbent at the base of the adsorber container and then cools the regenerated adsorbent before it leaves the adsorber container at the base to be conveyed to the top of the adsorber container. Knaebel emphasizes that additional cooling may occur during conveying.

[0011] Knaebel additionally provides a useful discussion of other prior art in the field, including Murakami et al.

[0012] For gas mixtures containing a large amount of gas adsorbed from the mixture as it flows through the adsorber, the volume change of the mixture can cause fluidization or flow problems in adsorbers with a series of spaced-apart fluidized beds. These problems include maintaining a sufficient gas velocity through each stage to sustain fluidization or even flow through the adsorber due to the reduced gas volume.

[0013] Any discussion of prior art throughout the specification is not an admission that such prior art is well-known or forms part of common knowledge in the art.

[0014] It should be noted that the moving bed configuration operates with a piston flow, which allows a single bed to have clearly defined adsorption and desorption zones. Any fluidization within the moving bed will disrupt this piston flow, thereby causing potentially undesirable mixing between zones, as such fluidization within the moving bed is considered detrimental to the operation of the moving bed device.

[0015] The present invention aims to improve some of the defects highlighted above or at least provide consumers with useful options. Summary of the Invention

[0016] The present invention provides an adsorption / desorption system configured to adsorb a certain proportion of feed gas into an adsorbent to produce treated gas and used adsorbent, and then desorb the feed gas from the used adsorbent in a proportion between 90% and 100% to produce desorbed gas, clean adsorbent and desorbed products. The adsorption / desorption system includes an adsorption circuit and a desorption circuit, wherein: - The adsorption circuit includes a multi-stage adsorption vessel with multiple vertically separated adsorber stages, such that each stage is configured as an independent bubbling fluidized bed operation as an adsorbent. - The desorption circuit includes a desorption container comprising a desorption stage configured to operate as a fluidized bed in a rapid fluid or gas lift / transport mode; and - The desorption stage is configured to use the desorption gas as a fluidizing gas and heat transfer medium to regenerate the used adsorbent; The desorbed gas is the gas from which the used adsorbent is desorbed to produce clean adsorbent. The desorbed product is a certain proportion of the desorbed gas removed from the desorption circuit as a product stream. When the adsorption / desorption system is in a steady state, the clean adsorbent is up to 100% of the adsorbent entering the adsorption container.

[0017] Preferably, the desorption circuit includes a desorption separator configured to receive output from the desorption container to separate the clean adsorbent from the desorption gas.

[0018] Preferably, the clean adsorbent is cooled and returned to the adsorption container.

[0019] In a highly preferred configuration, the desorbed gas from the desorption separator passes through a desorbed gas heat exchanger to return to the desorption container.

[0020] Preferably, the contents of the desorption container are 25°C to 75°C lower than the degradation temperature of the adsorbent. In a highly preferred form, the contents of the desorption container are 25°C to 75°C lower than the degradation temperature of the adsorbent, provided that the degradation temperature of the adsorbent is not higher than 400°C.

[0021] Preferably, the adsorbent has a maximum adsorption capacity for the feed gas of that proportion, and when introduced into the adsorption container, the clean adsorbent has at least 90% of this maximum adsorption capacity.

[0022] In an alternative form, the clean adsorbent has no more than 10% of the feed gas adsorbed compared to the proportion of feed gas adsorbed by the used adsorbent.

[0023] Preferably, the used adsorbent passes through a used adsorbent heat exchanger, wherein the temperature of the used adsorbent is adjusted before it is introduced into the desorption container.

[0024] Preferably, the adsorbent is a mixture of different types of gas adsorbents.

[0025] The present invention also includes a method for treating feed gas using an adsorbent in an adsorption / desorption system, the method comprising steps A to E, followed by step F or step G, wherein these steps are as follows: A. A clean adsorbent and a feed gas are fed into an adsorption container, wherein the clean adsorbent constitutes a certain proportion of the adsorbent fed into the adsorption container; B. Multiple vertically separated moving fluidized beds of adsorbent are formed in the adsorption container; C. The adsorbent is brought into countercurrent contact with the feed gas to form used adsorbent and treated gas; D. In a fluidized bed operating in a rapid fluid / gas lift fluidized bed mode, the used adsorbent is regenerated using a desorbed gas formed from the used adsorbent to form clean adsorbent and desorbed gas; E. Separate the clean adsorbent from the desorbed gas; F. Heating to desorb the gas; and G. Cool the adsorbent thoroughly; Step D follows step F, and step A follows step G.

[0026] Preferably, the feed gas is converted into a treated gas as it passes through the adsorption container. Preferably, a certain proportion of the desorbed gas is separated as a desorption product.

[0027] Preferably, step D is carried out at a temperature 25°C to 75°C lower than the decomposition temperature of the adsorbent. In a more preferred embodiment, step D is carried out at a temperature 25°C to 75°C lower than the decomposition temperature of the adsorbent.

[0028] Preferably, the cross-sectional area of ​​each adsorber stage decreases as it moves along the adsorption container from the feed stage where the feed gas is introduced to the outlet stage where the treated gas leaves the adsorption container.

[0029] In a preferred embodiment, the cross-sectional area is reduced by introducing an interstage flow controller. Preferably, the interstage flow controller is or includes a heat exchanger.

[0030] In an alternative variation, the cross-sectional area varies between adsorber stages as the adsorbent moves along the adsorbent vessel from the feed stage where the feed gas is introduced to the treated gas outlet stage where the treated gas exits the adsorbent vessel. Preferably, this variation is due to the presence of an interstage flow controller associated with each adsorber stage, which includes or may include an interstage heat exchanger.

[0031] In another alternative variation, at least one adsorber stage in the adsorber stage includes one or more inter-bed flow controllers, wherein each inter-bed flow controller extends into the fluidized bed of the adsorbent in this adsorber stage, occupying at least a certain proportion of the cross-sectional area of ​​the fluidized bed of the adsorbent.

[0032] Preferably, at least one of the at least one in-bed flow controllers is a heat exchanger.

[0033] Preferably, at least one of the at least one interbed flow controllers is capable of moving the fluidized bed through the adsorbent to a certain depth. Attached Figure Description

[0034] Preferred embodiments of the invention will be described in detail below with reference to the accompanying drawings, by way of example only, in which: Figure 1 is a schematic view of the adsorption / desorption system; Figure 2 is a partial cross-sectional view of a portion of the adsorber container showing the configuration of the first adsorber stage; Figure 3 is a partial cross-sectional view of a portion of the adsorber container showing the second adsorber stage configuration; Figure 4 is a schematic view of the main configuration of the desorption circuit; Figure 5 is a cross-sectional view of a portion of the main part of the desorption container, in which the used adsorbent and desorbed gas are fed onto the desorption bed support; Figure 6 This is a flowchart of a method for treating feed gas with an adsorbent and recovering the adsorbent using desorbed gas as a regenerator; Figure 7 is a drawn view of a variant of the adsorption container; Figure 8 is a cross-sectional view showing a portion of the adsorption container shown in Figure 7 of the adsorber stage; Figure 9 This is a drawing view of an alternative variation of the adsorber container; Figure 10 It is a schematic view of a variant of the adsorption container, including an interstage flow controller; Figure 11 It is a schematic view of a variant of the adsorption vessel, including the bed flow controller; Figure 12 yes Figure 11 Enlarged cross-sectional view of the highlighted area marked A in the middle; Figure 13 This is a graph showing the experimental-grade efficiency versus feed concentration at various bed depths for Example 6; and Figure 14 It is Figure 13 The graph shown compares the experimental results from Example 6 with the modeled results using the predictive model used in Examples 1 to 5, showing the recovery rate % versus feed concentration.

[0035] Please note that the accompanying drawings are not drawn to scale and may contain exaggerated or omitted features to improve clarity. Detailed Implementation

[0036] definition : Adsorbent: As used in this article, the adsorbent is a particulate material; Fixed bed: An adsorbent bed that is essentially fixed in place, through which the fluid to be treated moves; Moving bed: An adsorbent bed that moves across a support surface from one support surface to another under the influence of gravity, or crosses a support surface and then moves down and crosses the next support surface; Fluidized bed: A bed of adsorbent material that behaves like a fluid by forcing gas through it in the form of particles or separated material; Moving fluidized bed: An adsorbent material bed that combines the properties of a moving bed and a fluidized bed, in which the bed material continuously moves into and out of the bed.

[0037] Fast fluidized bed: A fluidized bed operating within the fast fluidization range. See Cocco, Ray & Karri, Sb & Knowlton, Ted. (2014). Introduction to Fluidization. Chemical Engineering Progress. 110. 21-29.

[0038] Geldart Classification: This is based on Geldart D (1986), Chapter 3: Characterization of Fluidized Powders, in Gas Fluidization Technology, John Wiley & Sons (Chichester, New York, Brisbane, Toronto, Singapore). For example, most particles used in fluidized beds are Geldart Class A (“Aerated”) and Geldart Class B (“Bubbling”). See Cocco, Ray & Karri, Sb & Knowlton, Ted. (2014). Introduction to Fluidization. Chemical Engineering Progress. 110. 21-29 for the size and density ranges of these classes.

[0039] Mostly: When used in this article, this term may independently mean greater than 90%, greater than 95%, greater than 98%, or greater than 99%.

[0040] Best way to carry out the invention

[0041] Referring to Figure 1, the adsorption / desorption system (1) includes an adsorption circuit (2) and a desorption circuit (3). The adsorption circuit (2) includes an adsorption container (5), which includes a feed gas line (7), a treated gas line (8), a clean adsorbent line (9), and a used adsorbent line (10).

[0042] The adsorption container (5) includes a first section (12) and a second section (13), wherein the first section (12) is the uppermost part of the adsorption container (5) including the top (14) of the adsorption container, and the second section (13) is the lowermost part of the adsorption container (5) including the base (15) of the adsorption container.

[0043] The adsorption container (5) also includes multiple vertically separated adsorber stages (18) extending from the first section (12) to the second section (13). Each stage includes an adsorber bed support (19).

[0044] During operation: - The feed gas line (7) serves as a conduit for the feed gas (20) to enter the second section (13), and the treated gas line (8) serves as a conduit for the treated gas (21) to leave the first section (12); - Each adsorbent line (9, 10) serves as a conduit for the adsorbent (23); - The clean adsorbent line (9) serves as the conduit for the clean adsorbent (25) to enter the first section (12), and the used adsorbent line (10) serves as the conduit for the used adsorbent (26) to exit the second section (13); and - Each adsorber bed support (19) supports a fluidized bed of adsorbents (23, 25, 26), namely the adsorber fluidized bed (28).

[0045] It should be noted that the term clean adsorbent (25) can refer to a regenerated adsorbent (23), a new or freshly added adsorbent (23), or a combination of these adsorbents. The term clean adsorbent (25) refers to an adsorbent (23) that adsorbs and desorbs gas (54) at 0% to 10% of the maximum capacity of the adsorbent (23).

[0046] The adsorber bed support (19) is most likely a perforated plate, which is designed to include any surface or support that is porous enough to allow gas flow through it to form a fluidized bed.

[0047] It is expected that each adsorber stage (18) will be independently selected from the following configurations: - The first adsorber stage configuration (30) shown in Figure 2; - The second adsorber stage configuration (31) shown in Figure 3; and - A combination of the first adsorber stage configuration (30) and the second adsorber stage configuration (31).

[0048] Each adsorber bed support (19) is a porous plate and / or comprises multiple plate perforations (29), wherein each plate perforation (29) may have any cross-sectional shape, i.e., circular, annular, rectangular-triangular, slotted, oblong-shaped, star-shaped (any number of points), or any combination of these shapes. It should be noted that the cross-sectional dimensions and / or shape of each plate perforation (29) may vary in thickness of the adsorber bed support (19).

[0049] Referring to Figure 2, a first adsorber stage configuration (30) is shown, in which the adsorber stage (18) includes an interstage conduit (35) and an adsorber stage weir (36). The interstage conduit (35) is a conduit / path that, during operation, delivers the adsorbent (23) from one adsorber stage (18) to the adsorbber stage (18) immediately below it, and is commonly referred to as a downcomer. The adsorber stage weir (36) is a piece of material extending above the adsorber bed support (19) that separates the adsorber bed support (19) from the interstage conduit (35). A portion of the interstage conduit (35) is typically connected to the adsorber stage weir (36). During operation, the adsorber stage weir (36) controls or sets the height (thickness) of the fluidized bed (28) of the adsorber on the associated adsorber bed support (19). When the adsorber bed support (19) includes plate perforations (29), the minimum cross-sectional dimension of each plate perforation (29) in this first adsorber stage configuration (30) is smaller than the minimum cross-sectional dimension of most of the adsorbent (23). It should be noted that even if each adsorber stage (18) shows a single interstage conduit (35), multiple distributed interstage conduits (35) may exist.

[0050] Referring to Figure 3, a second adsorber stage configuration (31) is shown, in which, during operation, a predetermined proportion of adsorbent (23) is allowed to drip through plate perforations (29). This predetermined flow rate of adsorbent (23) through plate perforations (29) is determined by the following: - The cross-sectional shape and dimensions of the perforation (29) in the plate; - Layout (configuration) of perforated plate (29); - The desired thickness of the fluidized bed (28) of the adsorber; - Gas flow rate through the perforation (29) of the plate; and - Physical properties of the adsorbent (23) (size, density, surface smoothness, etc.).

[0051] Referring to Figure 1, the adsorption container (5) includes a first adsorbent bed support (41) as part of a first adsorbent stage (42) and a last adsorbent bed support (45) as part of a last adsorbent stage (46). In the adsorption container (5), the first adsorbent stage (42) is the uppermost adsorbent stage (18), and the last adsorbent stage (46) is the lowermost adsorbent stage (18).

[0052] In use, the clean adsorbent line (9) feeds clean adsorbent (25) to the first adsorber stage (42), and the used adsorbent line (10) receives used adsorbent (26) from the last adsorber stage (46).

[0053] During operation, each adsorber fluidized bed (28) is controlled within the bubbling fluidization range to ensure good quality and heat transfer while minimizing entrainment and / or abrasion of the adsorbent (23).

[0054] Referring to Figure 4, a desorption circuit (3) is shown, comprising a desorption container (50), a desorption separator (51), and a desorption gas line (52). The desorption gas line (52) is a conduit for transporting the desorbed gas (54) from the desorption separator (51) to the main section (55) of the desorption container (50). The desorption container (50) also includes a secondary section (56), wherein the main section (55) and the secondary section (56) are vertically opposite end-positioned portions of the desorption container (50).

[0055] The main section (55) is the lowest part of the desorption container (50), and the secondary section (56) is the highest part of the desorption container (50).

[0056] In the primary configuration, as shown in Figures 4 and 5, the desorption container (50) includes a desorption bed support (58) located above the inlet of the desorbed gas line (52) and below the inlet of the used adsorbent line (10). The desorption bed support (58) is most likely a porous plate similar to the adsorber bed support (19) (see Figure 2). In some variations, the desorption bed support (58) includes multiple plate perforations (29) (see Figure 3 or Figure 4), where each plate perforation (29) can have any cross-sectional shape, i.e., circular, annular, rectangular triangular, slotted, oblong slotted, star-shaped (any number of points), or any combination of these shapes. It should be noted that the cross-sectional dimensions and / or shape of each plate perforation (29) can vary in the thickness of the desorption bed support (58). In operation, the desorption bed support (58) supports a desorption fluidized bed (62) operating within a rapid fluidized bed or gas lift / delivery range.

[0057] The desorption circuit (3) also includes a separator line (59) that runs from a secondary section (56) of the desorption container (50) to the desorption separator (51). The outlet of the desorption separator (51) is connected to the desorbed gas line (52) and the clean adsorbent line (9). In operation, the desorption separator (51) separates the desorbed gas (54) from the clean adsorbent (25) of the desired minimum size and directs them to the desorbed gas line (52) and the clean adsorbent line (9), respectively.

[0058] The desorption separator (51) is shown as a cyclone separator, which may be multiple cyclone separators, another form of inertial separator, gravity settling device, electrostatic separator or any known form of gas / solid separator, multiple of these separators and / or combination of these separators, as long as it can be configured to allow continuous operation.

[0059] Referring as necessary to Figures 1, 2, or 4, when the desorption circuit (3) is connected to the adsorption container (5) containing the first adsorbent stage configuration (30), in operation, the desorption separator (51) feeds a portion of clean adsorbent (25) with a minimum cross-sectional size suitable for the first adsorbent stage configuration (30) into the clean adsorbent line (9). Generally, this would mean that most of the clean adsorbent (25) in the clean adsorbent line (9) would have a minimum cross-sectional size greater than the minimum cross-sectional size of each plate perforation (29). By removing most of the size portion of the adsorbent (23) that will pass through the plate perforations (29), it minimizes the percentage of adsorbent that short-circuits any adsorbent stage (18). It can be understood that the size of the material passing through the plate perforations (29) depends not only on the size of the perforation but also on the gas velocity and shape of the perforation, so the minimum cross-sectional size of each plate perforation (29) can be greater than the minimum cross-sectional size of the adsorbent (23) particles because the gas velocity between perforations prevents the stages from short-circuiting.

[0060] Referring to Figure 4, the desorption circuit (5) also includes multiple heat exchangers (60, 61), namely one or more adsorbent heat exchangers (60) and one or more desorbed gas heat exchangers (61).

[0061] In operation, the adsorbent heat exchanger (60) cools the adsorbent (23) within or exiting the desorption separator (51). In one configuration, the adsorbent heat exchanger (60) surrounds or is incorporated into the base of the desorption separator (51), and additional adsorbent heat exchangers (60) are incorporated into the clean adsorbent line (9). The adsorbent heat exchanger (60) (or each of more than one adsorbent heat exchanger) is any suitable form of heat exchanger for cooling particulate solids, such as a direct contact heat exchanger using heat exchange surfaces, such as shell-and-tube, tube-in-tube, and plate heat exchangers, with or without fins.

[0062] The desorbed gas heat exchanger (61) heats the desorbed gas (54) in the desorbed gas line (52) before it enters the desorbed container (50) during operation. In this context, the desorbed gas heat exchanger (61) is intended to include a heater for heating the desorbed gas (54) without direct surface contact. For example, infrared, radio frequency, microwave, and standard gas heat exchanger configurations that use contact with a heated surface (such as shell-and-tube, tube-in-tube, plate, etc.) can be used alone or in combination to heat the desorbed gas (54).

[0063] In steady-state operation, the adsorption circuit (2) (see Figure 1, Figure 2 or Figure 3 if necessary) operates as follows: - Feed gas (20) into the second section (13) of the adsorption container (5) below the last adsorber bed support (45); - The feed gas (20) passes through the fluidized bed (28) of the adsorber in the last adsorber stage (46), and a certain proportion of the desorbed gas (54) in the feed gas (20) is adsorbed by the adsorbent (23); - The feed gas (20) moves upward along the adsorption container (5) and passes through the continuous adsorber stage (18), thereby reducing the amount of desorbed gas (54) present; - Control the number of adsorber stages (18), the depth of the fluidized bed (28) of the adsorber in each adsorber stage (18), the adsorbent flow rate, and the flow rate and temperature of the feed gas (20) so that the treated gas (21) leaving the first adsorber stage (42) has less than 30% and preferably less than 2% of desorbed gas (54) when it enters the treated gas outlet line (8). - When the feed gas (20) moves upward along the adsorption container from the last adsorber stage (46) to the first adsorber stage (42), the adsorbent (23) moves downward along the adsorption container (5) from the first adsorber stage (42) to the last adsorber stage (46). - A clean adsorbent (25) (an adsorbent (23) having 0% to 10% of the maximum capacity of the adsorbent (23) adsorbs the desorbed gas (54)) is fed into a first section (12) above the fluidized bed (28) of the adsorber supported by the first adsorber bed support (41) to adsorb a certain proportion of the desorbed gas (54) present in the gas passing through the fluidized bed (28) in the first adsorber stage (42). - The adsorbent (23) moves downward through a series of adsorber stages (18), adsorbing and desorbing gas (54) from the gas flowing upward along the adsorption container (5), and leaves the final adsorber stage (46) as used adsorbent (26); and - The used adsorbent (26) leaves the adsorption container (5) through the used adsorbent line (10).

[0064] In some configurations, the temperature of the feed gas (20), i.e., the feed gas temperature (TF), may need to be regulated before entering the adsorption container (5). If necessary, the temperature regulation of the feed gas (20) is performed in a feed gas heat exchanger (70). The feed gas heat exchanger (70) can be operated as required to heat or cool the feed gas (20), and if used for heating the feed gas (20), the feed gas heat exchanger (70) may include a heater similar to that of the desorption gas heat exchanger (61).

[0065] Although not shown, some configurations of the adsorption container may include heat exchangers that can regulate the temperature of one or more adsorbent fluidized beds in the existing adsorbent fluidized bed (28), namely the adsorbent bed temperature (TAB).

[0066] As shown in Figure 1, the treated gas outlet line (8) may include a treated gas particle separator (72), shown in dashed lines, to remove suspended adsorbent (23) particles carried with the treated gas (21). The treated gas particle separator (72) may be a device similar to a desorption separator (51), but with a different particle capture range.

[0067] In some configurations, referring to Figure 1, additional adsorbent (23) can be added, and supplementary adsorbent (73) can be added to replenish any adsorbent (23) lost due to wear. The supplementary adsorbent (73) is added to the clean adsorbent (25) before the adsorbent (23) enters the adsorption container (5). In Figure 1, the supplementary adsorbent (73) is shown as being added before the adsorbent heat exchanger (60) in the clean adsorbent line (9), and this supplementary adsorbent can be added at any point in the clean adsorbent line (9).

[0068] In steady-state operation, if necessary, refer to Figure 1, Figure 3 or Figure 4, and the desorption circuit (3) operates as follows: - The used adsorbent (26) is fed into the desorption container (3) via the used adsorbent line (10). Note that the "used" indicates that the adsorbent (23) has adsorbed the desorbed gas (54) from the feed gas (20), and it may be saturated with the desorbed gas (54) or contain more than the clean adsorbent (25). - The desorbed gas (54) from the desorbed gas heat exchanger (61) combines with the used adsorbent (26) above the desorbed bed support (58); - Maintain the feed rate of the desorbed gas (54) to ensure that the desorbed fluidized bed (62) is maintained in a fast fluid and / or gas lift mode, in which the adsorbent (23) in the desorbed container (3) moves in parallel with the desorbed gas (54); - The temperature of the gas and the adsorbent (23) is maintained at a desorption temperature (TD) higher than the temperature required to desorb the gas (54) from the adsorbent (23), which is most likely 25°C to 75°C lower than the decomposition temperature (DT) of the adsorbent, preferably about 50°C. - As the adsorbent (23) within the desorption fluidized bed (62) moves from the desorption bed support (58) to the separator line (59), the adsorbent moves from the used adsorbent (26) to the clean adsorbent (25). The clean adsorbent (25) leaving the desorption container (3) has less than 5%, and preferably less than 1%, of the adsorbed desorbed gas (54); - The desorbed gas (54) and the clean adsorbent (25) flow as a mixed stream through the separator line (59) to enter the desorption separator (51), in which the desorbed gas (54) and the clean adsorbent (25) having a particle size greater than a predetermined size are separated. The desorbed gas (54) leaves the desorption separator (51) through the desorbed gas line (52), and the clean adsorbent (25) leaves the desorption separator through the clean adsorbent line (9). - The clean adsorbent (25) in the clean adsorbent line (9) and / or the clean adsorbent before leaving the desorption separator (51) is cooled in the adsorbent heat exchanger (60) to a temperature (TCA) of less than 120°C, preferably less than 40°C and most preferably 15°C to 25°C. - A certain proportion of the desorbed gas (54) leaving the desorption separator (51) is separated into desorbed products (76) and transported through the desorbed product line (78); The retained desorbed gas (54) is heated in a desorbed gas heat exchanger (61) to a temperature that will maintain the desorbed fluidized bed (62) at a desorption temperature (TD) higher than that required to desorb the desorbed gas (54) from the adsorbent (23). Most likely, the desorption bed will be maintained at a temperature 25°C to 75°C, preferably about 50°C, lower than the adsorbent decomposition temperature (DT), which may mean that the desorbed gas (54) leaving the desorbed gas heat exchanger (61) is at or above DT before being fed into the desorption container (3).

[0069] A fast fluidized bed or a gas lift / transport fluidized bed is used for the desorption fluidized bed (62), and the temperature within the desorption fluidized bed (62) is maintained above the desorption temperature (TD) of the adsorbent (23). It is expected that for most adsorbents (23), the temperature of the desorption fluidized bed (62) will be 25°C to 75°C lower than the adsorbent decomposition temperature (DT), preferably about 50°C. Operating the desorption fluidized bed (62) under these conditions is expected to result in a desorbed gas (54) purity greater than 70%, noting that the purity of the desorbed gas (54) will depend on the composition of the gas feed (20) and the properties of the adsorbent (23). Surprisingly, based on simulations, using the adsorbed gas as the desorbed gas in combination with a fast fluidization or gas lift fluidization mode with sufficient residence time results in high purity (typically greater than 70%) and high recovery rates (greater than 90% and typically close to 99%) of the product (76) from the desorption of the target substance (this needs to be confirmed in further physical experiments).

[0070] It should be noted that for high-temperature adsorbents (23), where the decomposition temperature (DT) is above about 400°C, the desorption fluidized bed (62) is expected to operate at a temperature much lower than DT by more than 75°C, although this remains to be confirmed.

[0071] In some configurations, the temperature (TSA) of the used adsorbent (26) can be regulated using an optional used adsorbent heat exchanger (74) in the used adsorbent line (10) before it is fed into the desorption container (3). The used adsorbent heat exchanger (74) is similar to the desorption gas heat exchanger (61) in that it can be a heater and / or includes a heater.

[0072] In some configurations, referring to Figure 4, a fine particle separator (80) is present in the desorption gas line (52) to remove adsorbent (23) having a particle size smaller than that removed in the desorption separator (51). The fine adsorbent particles (i.e., fine particles (81)) removed by the fine particle separator (80) are discharged for recycling, reprocessing, or disposal.

[0073] In some configurations (not shown), the desorption vessel includes one or more extended sections that increase the residence time while still maintaining operation within the range of rapid fluidization and / or gas lift / delivery.

[0074] The present invention also includes a method for treating a feed gas using an adsorption / desorption system as described above. The method includes, but is not limited to, the sequential steps A through E; F and G can occur simultaneously because they involve different streams. A. Feed the clean adsorbent and feed gas into the adsorption container; B. Multiple vertically separated moving fluidized beds of adsorbent are formed in the adsorption container; C. The adsorbent is brought into countercurrent contact with the feed gas to form used adsorbent and treated gas; D. In a fluidized bed operating in a rapid fluid / gas lift fluidized bed mode, desorbed gas is used to regenerate the used adsorbent to form clean adsorbent and desorbed gas; E. Separate the clean adsorbent from the desorbed gas; F. Heating to desorb the gas.

[0075] G. Cool and clean the adsorbent.

[0076] In step A, clean adsorbent (25) is fed into the first adsorber stage (42) and feed gas (20) is fed into the last adsorber stage (46). After step A, step B is performed.

[0077] In step B, the adsorbent (23) moves downward along the adsorption container (5) sequentially into each adsorber stage (18) and interacts with the gas flowing upward along the adsorption container (5) to form multiple vertically separated adsorber fluidized beds (28). Each adsorber fluidized bed (28) will preferably be a bubbling fluidized bed. Step C is performed after step B.

[0078] In step C, the feed gas (20) moves countercurrently to the adsorbent (23), contacting the adsorbent (23), wherein a certain proportion of the feed gas (20) is adsorbed by the adsorbent (23). As the feed gas (20) moves upward along the adsorption container (5), an increased proportion of the feed gas (20) is lost to the adsorbent (23), becoming treated gas (21). As the clean adsorbent (25) moves downward along the adsorption container (5), it adsorbs an increased proportion of the feed gas (20) to become used adsorbent (26). The used adsorbent (26) may be saturated with the proportion of feed gas (20) it has adsorbed, or it may not be saturated. After step C, step D is performed.

[0079] In step D, the used adsorbent (26) is transferred to a desorption container (3), where it is mixed with desorbed gas (54) to form a fluidized bed operating in a fast fluid or gas / lift / conveyor mode. As the used adsorbent (26) moves upward along the desorption container (3), the adsorbed proportion of feed gas (20) is desorbed from the adsorbent (23) as desorbed gas (54). As the used adsorbent (26) moves upward along the desorption container (3) and desorbs the desorbed gas (54) (a proportion of feed gas (20) adsorbed by the adsorbent (23)), the used adsorbent is returned to the clean adsorbent (25). Step E is performed after step D.

[0080] In step E, the desorbed gas is separated from the clean adsorbent (25) in a desorption separator (51), which is a particle / gas separator, such as a cyclone separator. The particle size cutoff for the desorption separator will most likely be between 20 micrometers and 100 micrometers, making the clean adsorbent (25) suitable for step A, although it can be as low as 10 micrometers.

[0081] After step E, step F or step G is performed, where step G is performed with the clean adsorbent (25) leaving the desorption separator (51) and step F is performed with the desorbed gas (54) leaving the desorption separator (51).

[0082] In step F, the desorbed gas (54) leaving the desorption separator (51) is heated directly and / or via a heat exchanger (i.e., the desorbed gas heat exchanger (61)) to a temperature that causes the desorption fluidized bed (62) to operate at a temperature 25 K to 75 K lower than the destruction temperature (DT) of the adsorbent (23). After step F, step D is performed.

[0083] In step G, the clean adsorbent (25) is cooled to below the desorption temperature (TD) of the adsorbent (23) used, typically to a temperature low enough to account for any expected temperature rise of the adsorbent (23) within the adsorption container (5). After step G, step A is performed.

[0084] Additional steps may be performed between the indicated steps; however, as previously indicated, the above steps are performed sequentially, except for steps F and G, which are performed on separate streams and therefore can occur simultaneously.

[0085] It should be noted that in step F, for an adsorbent with a DT greater than about 400°C, the desorption fluidized bed (62) is expected to operate at a temperature much lower than DT by more than 75 K.

[0086] Surprisingly, using only the regenerated desorbed gas from the adsorbents (23, 25, 26), the desorbed gas (54), combined with a fluidized bed operating in a rapid fluid or gas lift delivery mode at a temperature far exceeding the desorption temperature typically used in prior art systems, resulted in higher-than-expected yields and purities of both the treated gas (21) and the desorbed gas (54). Using the desorbed gas (54) as the fluidizing gas reduces the need for fractionation or separation of stripping gas from the desorbed gas (54), meaning that the desorbed gas can be used directly as the desorbed product (76). Interestingly, the yields of the product streams (treated gas (21) and desorbed product (76)) appear to be unaffected.

[0087] In an alternative configuration not shown, one or more heat exchangers and / or heating / cooling devices may be present within the adsorption vessel (5) and / or desorption vessel (50). These one or more heat exchangers and / or heating / cooling devices may be any of the heat exchangers or heating / cooling devices mentioned above, including fluidized beds or any other suitable devices. Any of these heat exchangers may be finned, unfinned, or include extrusion sections / protrusions, etc., to improve heat transfer between gas particles.

[0088] It should be noted that when using the terms adsorbent heat exchanger (60), desorbed gas heat exchanger (61), feed gas heat exchanger (70) or used adsorbent heat exchanger (74), there may be more than one physical heat exchanger or heater / cooling device.

[0089] Referring to Figure 1, an optional heat exchanger fluidizing gas line (82) feeds the used adsorbent heat exchanger (74) to make it a fluidized bed heat exchanger. The heat exchanger fluidizing line (82) delivers a certain proportion of desorbed gas (54) from the desorbed gas line (52) to the used adsorbent heat exchanger (74).

[0090] Referring to Figures 7 and 8, a variant of the adsorption container (5) and a cross-sectional view of an adsorber stage (18) of the variant are shown, respectively.

[0091] In this variant, the cross-sectional area of ​​the adsorption container (5) changes as it moves from the base (15) to the top (14) of the adsorption container, such that the cross-sectional area of ​​the adsorber bed support (19) at or near the base (15) is greater than that at or near the top (14). Therefore, the cross-sectional area of ​​the last adsorber stage (46) at or near the base (15) is greater than that of the first adsorber stage (42) to account for the adsorption and desorption of gas (54) from the feed gas.

[0092] It can be assumed that by changing the cross-sectional area of ​​the adsorber stage (18), in which the feed gas (20) contains a significant proportion of the desorbed gas (54), the effect of the volume change of the gas moving upward along the adsorption container (5) due to adsorption will be minimized. By changing the cross-sectional area of ​​the adsorber stage (18), it is expected that each adsorber stage can be better controlled, and the adsorption efficiency of each adsorber stage (18) will be easier to control and maintain.

[0093] Referring to Figure 8, a modified adsorber stage (18) configuration is shown in which the walls of the adsorption container (5), the interstage conduits (35), and the adsorber stage weir (36) are angled. The interstage conduits (35) and the adsorber stage weir (36) are shown as parallel to the walls of their nearest adsorption container (5). This is only one possible configuration, and they may be perpendicular (or more closely perpendicular) to the adsorber bed support (19).

[0094] Referring to Figure 8, the cross-sectional changes between the adsorbent stages (18) will depend on the adsorbent (23), the composition of the feed gas (20), the flow rate of the feed gas (20), and the configuration of each adsorbent stage (18) required to maintain the fluidized bed of the adsorbent (23) on the adsorbent bed support (19).

[0095] refer to Figure 9 For easier construction, an alternative variant of the adsorption container (5) is shown to have a stepped rather than conical structure.

[0096] refer to Figure 10 This is a schematic view showing the internal components of a variant of the adsorption container (5) including interstage flow controllers (92). Each interstage flow controller (92) is present to change the flow cross-section of the interstage gas (94) in the adsorption container (5) and / or the temperature of the interstage gas (94) to mitigate the effect of the adsorbent (23) adsorbing the components of the interstage gas (94). The interstage gas (94) is the gas that moves between the adsorber stages (18).

[0097] The interstage flow controller (92) can: - Simply reduce the flow cross-section between adjacent stages in the adsorption container (5) to change the flow velocity of the interstage gas (94); - It is an interstage heat exchanger (96) that regulates the temperature of the interstage gas (94); or - It is an interstage heat exchanger (96) that regulates the temperature and flow rate of the interstage gas (94).

[0098] It should be noted that, Figure 10In this context, the location and size of each interstage flow controller (92) depend on the requirements of the adsorber stage (18), and the locations shown in the figures are merely non-limiting examples.

[0099] The adsorption that occurs within the adsorption container (5) can affect the flow of the interstage gas (94) for any or all of the following reasons: - The adsorption of components in the feed gas (20) or interstage gas (94) is usually exothermic, which can change the volume and temperature of the interstage gas (94); - If the temperature of the interstage gas (94) changes, the temperature of the adsorbent (23) will increase, which may change the adsorption properties of the adsorbent (23); - The volume of the interstage gas (94) is changed by adsorbing a certain proportion of the interstage gas or feed gas by the adsorbent (23); Any change in the temperature or volume of the interstage gas (94) could adversely affect the operation of subsequent adsorber stages (18) by altering the bed depth or other characteristics of the fluidized bed that contacts the adsorbent (23) with the interstage gas (94) or the feed gas (20).

[0100] refer to Figure 11 And refer to when necessary Figure 12 A variation of the adsorber container (5) is shown, in which each adsorber stage (18) includes one or more interbed flow controllers (100). Each interbed flow controller (100) changes the cross-sectional area of ​​the fluidized bed of adsorbent (23).

[0101] In this variant, some or all of the adsorber stages (18) include one or more inter-bed flow controllers (100). Each inter-bed flow controller (100) extends through at least a portion of the fluidized bed of adsorbent (23) on top of the adsorber bed support (19) in the adsorber stage (18). By occupying a portion of the volume of the fluidized bed of adsorbent (23), the cross-sectional area of ​​the fluidized bed of adsorbent (23) is reduced. This reduction in cross-sectional area can be used to ensure that the fluidized bed of adsorbent (23) in each adsorber stage (18) can be at least partially optimized for gas adsorption.

[0102] For example, by reducing the available cross-sectional area of ​​the adsorbent (23), the velocity of the feed gas (20) or interstage gas (94) through the fluidized bed of the adsorbent (23) increases. The reduction in the available cross-sectional area of ​​the adsorbent (23) can increase the bed depth and / or the flow path of the interstage gas (94) or feed gas (20) through the fluidized bed of the adsorbent (23) in the adsorber stage (18).

[0103] Figure 12Several different configurations of the bed-to-bed flow controller (100) are shown to illustrate that they can differ in side view shape, although in many cases they will all have the same side view shape (shown as dashed lines). For example, some of the different side view shapes shown are: - The first bed flow controller (100a) is shown as a constant size in the side view, with one side in contact with the adsorber bed support (19). - The second bed flow controller (100b) is shown as a trapezoid in the side view, with the shortest side adjacent to the adsorber bed support (19). - The third bed flow controller (100c) is shown as a trapezoid in the side view, with its shortest side opposite the adsorber bed support (19); and - The fourth interbed flow controller (100d) is shown as a constant size in the side view, with a gap between the interbed flow controller (100d) and the adsorber bed support (19).

[0104] Each of these shapes of the interbed flow controllers (100, 100a, 100b, 100c, 100d) will modify the fluidized bed of the adsorbent (23) in a different way, thereby allowing changes in the properties of the fluidized bed of the adsorbent (23). Some interbed flow controllers (100, 100a, 100b, 100c, 100d) will allow for differences in flow characteristics depending on the bed depth, i.e., those interbed flow controllers with a conical shape, such as the second and third interbed flow controllers (100b, 100c).

[0105] It should be noted that although various shapes of inter-bed flow controllers (100, 100a, 100b, 100c, 100d) are shown, they can all be identical, or the shape can be selected independently for each inter-bed flow controller. Although the inter-bed flow controller (100) with a curved side is not shown in the side view, this configuration is considered acceptable.

[0106] Each of the interbed flow controllers (100, 100a, 100b, 100b, 100c, 100d) can also be an interbed heat exchanger (102), which is a heat exchanger capable of cooling or heating the adsorbent (23) in a fluidized bed. Depending on the internal configuration of the interbed heat exchanger (102), this cooling or heating can be directed to a specific height within the bed of adsorbent (23). Some interbed heat exchangers (102) can also directly cool or heat the interstage gas (94) above the fluidized bed of adsorbent (23), thus acting as an interstage heat exchanger (96) (see, for example, [reference needed]). Figure 10 ).

[0107] The properties of the fluidized bed of the adsorbent (23) can be changed in situ by using interbed flow controllers (100, 100a, 100b, 100c, 100d). If some or all of the interbed flow controllers (100, 100a, 100b, 100c, 100d) can be dynamically inserted into different depths in the fluidized bed of the adsorbent (23), a feedback loop that takes into account changes in the properties of the feed gas (20) or the interstage gas (94) can be realized.

[0108] The cross-sectional shape of the reverse adsorption container (5) of each inter-bed flow controller (100, 100a, 100b, 100c, 100d) can also vary along the length of the inter-bed flow controller (100, 100a, 100b, 100c, 100d). The cross-sectional shape of this reverse adsorption container (5) of each inter-bed flow controller (100, 100a, 100b, 100c, 100d) can be any curved or straight-walled closed shape, including but not limited to polygons, circles, semicircles, ellipses, parabolas, hyperbolas, or stars with 3 to 100 sides.

[0109] Some variations (not shown) of the interbed flow controller (100, 100a, 100b, 100c, 100d) may have a gas path along the length direction to allow a certain proportion of the feed gas (20) or interstage gas (94) to pass through a portion of the fluidized bed of the adsorbent (23).

[0110] Example

[0111] The results of Examples 1 through 5 are based on computer simulations using feed gases containing methane and nitrogen or propylene and propane. Typical model assumptions / limitations apply. Example 6 compares the experimental data with computer simulation predictions using gases containing carbon dioxide and nitrogen.

[0112] Adsorbent: AC = Activated carbon; Zn(dcpa) = Zn(2,6-dichlorophenylacetic acid ester) V2Cl 2.8 (btdd) (H2btdd, bis(1H-1,2,3-triazolo[4,5-b],[4',5'-i])dibenzo[1,4]dioxin); HIAM-301 = Y6(OH)8(eddi)3(DMA)2 (represented as HIAM-301, where HIAM refers to the Hoffmann Institute for Advanced Materials, H4eddi = 5,5'-(ethylene-1,2-diyl)diisophthalic acid, and DMA = dimethylammonium)

[0113] Example 1 Configuration: 10 adsorber stages and 1 desorption stage.

[0114] The feed gas composition is 85% methane and 15% nitrogen.

[0115] Adsorbent = granular AC.

[0116] Adsorber temperature = 300K.

[0117] Pressure = 100 kPa.

[0118] Desorption container temperature = 1023K (granular AC) (decomposition temperature less than 50℃).

[0119] The feed gas flow rate is 1 mol / s.

[0120] The flow rate of the desorbed gas to the desorption container is 1 mol / s.

[0121] result

[0122] For an adsorbent flow rate of 0.63 kg / s through the adsorption container, methane purity = 95%, and methane recovery rate = 99%.

[0123] Example 2 Configuration: 10 adsorber stages and 1 desorption stage.

[0124] The feed gas composition is 85% methane and 15% nitrogen.

[0125] Adsorbent = Zn(dcpa).

[0126] Adsorber temperature = 300K.

[0127] Pressure = 100 kPa.

[0128] Desorption container temperature = 600K (Zn(dcpa)) (decomposition temperature less than 50℃).

[0129] ○ The feed gas flow rate is 1 mol / s at 85 (methane) / 15 (nitrogen).

[0130] ○ Desorption gas flow rate to the desorption container: 1 mol / s.

[0131] result

[0132] For Zn(dcpa) with an adsorbent flow rate of 1.33 kg / s through the adsorption vessel, methane purity = 96% and methane recovery rate = 98%.

[0133] Example 3 Configuration: 10 adsorber stages and 1 desorption stage.

[0134] The feed gas composition is 85% methane and 15% nitrogen.

[0135] Adsorbent = V2Cl 2.8 (btdd).

[0136] Adsorber temperature = 300K.

[0137] Pressure = 100 kPa.

[0138] Desorption container temperature = 403K (V2Cl) 2.8 (btdd) (decomposition temperature less than 50℃).

[0139] The feed gas flow rate is 1 mol / s.

[0140] The flow rate of the desorbed gas to the desorption container is 1 mol / s.

[0141] result

[0142] For V2Cl 2.8 (btdd) (nitrogen selective) adsorbent flow rate through the adsorption container is 0.11 kg / s, methane purity = 99%, methane recovery rate = 98%.

[0143] Example 4 Configuration: 10 adsorber stages and 1 desorption vessel stage.

[0144] Feed gas composition: 50% propylene, 50% propane.

[0145] Adsorbent = AgY zeolite.

[0146] Adsorber temperature = 300K.

[0147] Pressure = 100 kPa.

[0148] Desorption container temperature = 1123K (AgY zeolite) (decomposition temperature less than 50℃).

[0149] The feed gas flow rate is 1 mol / s.

[0150] The flow rate of the desorbed gas into the desorption container is 1 mol / s.

[0151] result

[0152] For AgY zeolite, the adsorbent flow rate through the adsorption container is 0.20 kg / s, the propylene purity is 90%, and the propylene recovery rate is 99%.

[0153] Example 5 Configuration: 10 adsorber stages and 1 desorption vessel stage.

[0154] Feed gas composition: 50% propylene, 50% propane.

[0155] Adsorbent = HIAM-301.

[0156] Adsorber temperature = 300K.

[0157] Pressure = 100 kPa.

[0158] Desorption container temperature = 423K (HIAM-301) (decomposition temperature less than 50℃).

[0159] The feed gas flow rate is 1 mol / s.

[0160] The flow rate of the desorbed gas into the desorption container is 1 mol / s.

[0161] result

[0162] For HIAM-301, the adsorbent flow rate through the adsorption container is 0.26 kg / s, the propylene purity is 99%, and the propylene recovery rate is 99%.

[0163] Example 6 Configuration: 1 adsorber stage (variable bed height), 1 desorption vessel stage.

[0164] Feed gas composition: 5-25% carbon dioxide, 75-95% nitrogen.

[0165] Adsorbent = Morden zeolite.

[0166] Adsorber temperature = 298-333K.

[0167] Pressure = 100 kPa.

[0168] The temperature of the desorption container is 355-385K.

[0169] The feed gas flow rate is 3.5 L / min.

[0170] The flow rate of the desorption gas into the desorption container is 40 L / min.

[0171] result

[0172] refer to Figure 13 and Figure 14 The experimental results shown validate the modeled performance with 95% accuracy. For experimental bed heights of 20–80 mm, the adsorption stage exhibits a purity efficiency of 75–95% (i.e., 75–95% of the predicted equilibrium performance). Figure 13 The experimental recovery efficiency was 83-87%, within 10% uncertainty of the modeled results.

[0173] Figure 13 Experimental results for feed concentration (in mol%) versus stage efficiency (in percentage) at bed depths of 20 mm, 30 mm, 45 mm, and 80 mm are shown (marked with E).

[0174] Figure 14The graphs show feed concentration (mol%) versus recovery (%) for both experimental (solid markers marked E in the label table) and modeled (hollow markers marked M in the label table) scenarios. The solid line represents the best fit of KEY.

[0175] 1. Adsorption / desorption system; 2. Adsorption circuit; 3. Desorption circuit; 5. Adsorption container; 7. Feed gas pipeline; 8. Treated gas outlet pipeline; 9. Clean adsorbent pipeline; 10 Used adsorbent pipelines; 12 First section (the uppermost part of the adsorption tower); 13 Second section (the lowest section of the adsorption tower); 14. Top of the adsorption container; 15. Base of the adsorption container; 18. Adsorber stage; 19. Adsorber bed support components; 20. Feed gas; 21. Processed gas; 23. Adsorbent; 25 Clean adsorbent; 26 Used adsorbents; 28. Adsorber fluidized bed; 29. Perforation of the plate; 30. First Adsorber Stage Configuration; 31. Second Adsorber Stage Configuration; 35-level piping; 36. Adsorber stage weir; 41 First Adsorber Bed Support; 42 First Adsorber Stage; 45. Final adsorber bed support; 46. ​​Final Adsorber Stage; 50 Desorption container; 51 Desorption separator; 52. Desorption gas pipeline; 54. Desorbed gas; 55. Main section (the lowest section of the desorption container); 56. Secondary section (the uppermost section of the desorption container); 57; 58. Desorption bed support components; 59. Separator piping; 60 Adsorbent heat exchanger; 61. Desorption gas heat exchanger; 62. Desorption fluidized bed; 70 Feed gas heat exchanger; 72. Processed gas particle separator; 73. Supplement the adsorbent; 74 Used adsorbent heat exchangers; 76. Products of desorption; 78. Desorbed product pipeline; 80 Fine particle separator (optional); 81 Fine particles; 82. Fluidized gas pipeline for heat exchanger; 92-level inter-level flow controller; 94-stage interphase gas; 96-level inter-level flow controller; 100 (including 100a to 100d) bed-to-bed flow controllers; 102. In-bed heat exchanger.

Claims

1. An adsorption / desorption system configured to adsorb a certain proportion of feed gas into an adsorbent to produce a treated gas and used adsorbent, and then desorb 90% to 100% of the feed gas from the used adsorbent to produce a desorbed gas, clean adsorbent, and desorbed products; the adsorption / desorption system comprising an adsorption circuit and a desorption circuit, wherein: - The adsorption circuit includes a multi-stage adsorption vessel with multiple vertically separated adsorber stages, such that each stage is configured as an independent bubbling fluidized bed operating as an adsorbent. - The desorption circuit includes a desorption container, the desorption container includes a desorption stage, the desorption stage being configured to operate as a fluidized bed in a rapid fluid or gas lift / transport mode; and -The desorption stage is configured to use the desorption gas as a fluidizing gas and heat transfer medium to regenerate the used adsorbent; The desorbed gas is the gas from which the used adsorbent is desorbed to produce the clean adsorbent, the desorbed product is a certain proportion of the desorbed gas removed from the desorption circuit as a product stream, and when the adsorption / desorption system is in a stable state, the clean adsorbent is up to 100% of the adsorbent entering the adsorption container.

2. The adsorption / desorption system of claim 1, wherein, The desorption circuit includes a desorption separator configured to receive an output from the desorption container to separate the clean adsorbent from the desorbed gas.

3. The adsorption / desorption system of claim 1 or claim 2, wherein, The clean adsorbent is cooled and returned to the adsorption container.

4. The adsorption / desorption system according to any one of claims 1 to 3, wherein, The desorbed gas from the desorption separator passes through a desorption gas heat exchanger to return to the desorption container.

5. The adsorption / desorption system according to any one of claims 1 to 4, wherein, The contents of the desorption container are 25°C to 75°C lower than the degradation temperature of the adsorbent.

6. The adsorption / desorption system according to any one of claims 1 to 4, wherein, When the degradation temperature of the adsorbent is not higher than 400°C, the contents of the desorption container are 25°C to 75°C lower than the degradation temperature.

7. The adsorption / desorption system according to any one of claims 1 to 6, wherein, The adsorbent has a maximum adsorption capacity for the feed gas in the specified proportion, and when introduced into the adsorption container, the clean adsorbent has at least 90% of this maximum adsorption capacity.

8. The adsorption / desorption system according to any one of claims 1 to 6, wherein, When compared to the proportion of feed gas adsorbed by the used adsorbent, the clean adsorbent has no more than 10% of the proportion of feed gas adsorbed.

9. The adsorption / desorption system according to any one of claims 1 to 8, wherein, The used adsorbent passes through a used adsorbent heat exchanger, where the temperature of the used adsorbent is adjusted before it is introduced into the desorption container.

10. The adsorption / desorption system according to any one of claims 1 to 9, wherein, The adsorbent is a mixture of different types of gas adsorbents.

11. A method for treating a feed gas using an adsorbent in an adsorption / desorption system, the method comprising steps A to E, followed by step F or step G, wherein the steps are as follows: A. A clean adsorbent and a feed gas are fed into an adsorption container, wherein the clean adsorbent constitutes a certain proportion of the adsorbent fed into the adsorption container; B. Multiple vertically separated moving fluidized beds of the adsorbent are formed in the adsorption container; C. The adsorbent is brought into countercurrent contact with the feed gas to form used adsorbent and treated gas; D. In a fluidized bed operating in a rapid fluid / gas lift fluidized bed mode, the used adsorbent is regenerated using a desorbed gas formed from the used adsorbent to form a clean adsorbent and the desorbed gas; E. Separate the clean adsorbent from the desorbed gas; F. Heating to desorb the gas; and G. Cool the cleaned adsorbent; Step D follows step F, and step A follows step G.

12. The method according to claim 11, wherein, The feed gas is converted into a treated gas as it passes through the adsorption container.

13. The method according to claim 11 or claim 12, wherein, A certain proportion of the desorbed gas is separated as a desorption product.

14. The method according to any one of claims 11 to 13, wherein, Step D is carried out at a temperature 25°C to 75°C lower than the degradation temperature of the adsorbent.

15. The method according to any one of claims 11 to 13, wherein, Step D is performed at a temperature 25°C to 75°C lower than the destructive temperature of the adsorbent, only when the destructive temperature of the adsorbent is 400°C or lower.

16. The adsorption / desorption system according to any one of claims 1 to 10, wherein, As the adsorbent moves along the adsorption container from the feed stage where the feed gas is introduced to the outlet where the treated gas exits the adsorption container, the cross-sectional area of ​​each adsorber stage decreases.

17. The adsorption / desorption system according to claim 16, wherein, The cross-sectional area is reduced by introducing an interstage flow controller.

18. The adsorption / desorption system according to claim 16 or claim 17, wherein, Interstage flow controllers are or include heat exchangers, or interstage heat exchangers.

19. The adsorption / desorption system according to any one of claims 1 to 10, wherein, Because of the presence of an interstage flow controller associated with each adsorber stage, which includes or serves as an interstage heat exchanger, the cross-sectional area varies between the adsorber stages as the adsorption vessel moves from the feed stage where the feed gas is introduced to the treated gas outlet stage where the treated gas leaves the adsorption vessel.

20. The adsorption / desorption system according to any one of claims 1 to 10, wherein, At least one of the adsorber stages includes one or more inter-bed flow controllers, wherein each inter-bed flow controller extends into the fluidized bed of the adsorbent in this adsorber stage and occupies at least a certain proportion of the fluidized bed of the adsorbent.

21. The adsorption / desorption system according to claim 20, wherein, At least one of the at least one in-bed flow controllers is a heat exchanger.

22. The adsorption / desorption system according to claim 20 or 21, wherein, At least one of the at least one interbed flow controllers is configured to move through the fluidized bed of the adsorbent to a depth.

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