Abstract: High product recovery and low BSF are achieved for fast-cycle shallow adsorbers in VPSA gas separation enabled by the coupled effects of high intrinsic adsorption rate and proper particle size selection.

Abstract: A gas transfer segment of a vacuum swing adsorption process cycle utilizing multiple parallel adsorbent beds which undergo cyclic process steps to separate the components of a feed gas mixture, each bed having a feed end and a product end, wherein the gas transfer segment comprises a step of withdrawing a waste gas stream from the feed end of a first bed, withdrawing a transfer gas from the product end of the first bed and introducing the transfer gas into the product end of a second bed, and withdrawing a waste gas stream from the feed end of the second bed.

Abstract: A method for operating a pressure swing adsorption process at turndown conditions by adding selected steps to the normal design operation of the process. The selected steps include the extension of a make product/no feed step and the addition of idle steps at specific points in the process cycle during depressurization and repressurization. The average volumetric flow ratio of the pressurized feed gas to the final product gas during design operation and during turndown operation may be essentially equal. The average oxygen concentration in the final product gas during design operation and during turndown operation also may be essentially equal.

Abstract: A gas mixture comprised of nitric oxide and one or more impurities selected from nitrous oxide, nitrogen dioxide, nitrous acid, sulfur dioxide, carbonyl sulfide, water vapor and carbon dioxide is purified by pressure swing adsorption or temperature swing adsorption using a porous, metal-free polymer adsorbent that does not promote the disproportionation of nitric oxide to nitrogen dioxide and nitrogen or nitrous oxide. The adsorption step is preferably carried out at tempereatures in the range of about −120 to about 0° C.

Abstract: The present invention relates to a novel family of inorganic solids with a narrow and calibrated mesopore distribution which are agglomerated with a binder; these solids can advantageously be used as adsorbents for the industrial separation of gas-phase compounds having different boiling points.

Abstract: A pressure swing process and system for purifying a first gas, preferably argon, from a crude feed gas stream containing the first gas and second gas(es) utilizes two adsorption beds and continuously promotes the crude feed gas to the bed during the process and simultaneous equalization of pressure in the two beds in top-to-top end and bottom-to-bottom end equalizations in each bed following purging of each bed.

Abstract: A two bed vacuum swing adsorption process for the production of oxygen is disclosed. Efficient use of air blowers and vacuum pumps maximizes the machine utilization and product gas purges in low flow and high flow modes to increase productivity while lessening power consumption.

Abstract: A method of separating a first gaseous component from a gas mixture comprising a first gaseous component and a second gaseous component comprising passing the gaseous mixture into an adsorption zone containing an adsorbent material capable of preferentially adsorbing at least one of the gaseous components in the gaseous mixture, to separate the first gaseous component from the second gaseous component wherein the adsorbent material is a monolithic wheel having a plurality of channels throughout, the channels being aligned parallel to the direction of flow of the gaseous mixture and having a wall thickness of less than 1 mm and recovering the non-preferentially adsorbed gaseous component from the adsorption zone. Preferably, the adsorption zone comprises multiple layers of monolithic structures in the shape of a wheel stacked one upon the other in a direction parallel to the direction of the flow of the gaseous mixture and formed by spirally winding a sheet of corrugated adsorbable material about a hub.

Abstract: The gas treatment installation operating on a treatment cycle, in which part of the cycle is performed at a pressure below atmospheric pressure, particularly a PSA, TSA or VSA installation, includes one or more gas treatment vessels containing adsorbent. Each vessel has at least one orifice, at least one gas pipe communicating with the orifice, at least one valve arranged on the gas pipe and controlling the flow of the gas flowing through the pipe. The valve comprises a shaft for operating the valve and sealing elements. A device for maintaining a protective gaseous atmosphere is arranged around the sealing elements and the operating shaft to create and to maintain a protective gaseous atmosphere around these items and thus prevent the ingress, into the treatment vessel, of contaminants harmful to the adsorbent, particularly the ingress of moisture liable to deactivate the molecular sieve, that is to say the adsorbent.

Abstract: A pressure swing adsorption system for separating components of a gas mixture includes a first adsorbent module, and a second a adsorbent module coupled to the a first adsorbent module. The first adsorbent module includes a first gas inlet for receiving the gas mixture, at least one bed of first adsorbent material in communication with the first gas inlet for adsorbing a gas mixture component from the gas mixture, and a first gas outlet in communication with the first adsorbent beds for receiving a first product gas therefrom. The second adsorbent module includes a second gas inlet coupled to the first gas outlet for receiving the first product gas, at least one second bed of adsorbent material in communication with the second gas inlet for adsorbing a first product gas component from the first product gas, and a second gas outlet in communication with the second adsorbent beds for receiving a second product gas therefrom.

Abstract: Gas separation by pressure swing adsorption (PSA) and vacuum pressure swing adsorption (VPSA), to obtain a purified product gas of the less strongly adsorbed fraction of the feed gas mixture, is performed with an apparatus having a plurality of adsorbers. The adsorbers cooperate with first and second valves in a rotary PSA module, with the PSA cycle characterized by multiple intermediate pressure levels between the higher and lower pressures of the PSA cycle. Gas flows enter or exit the PSA module at the immediate pressure levels as well as the higher and lower pressure levels, under substantially steady conditions of flow and pressure. The PSA module comprises a rotor containing laminated sheet adsorbers and rotating within a stator, with ported valve faces between the rotor and stator to control the timing of the flows entering or exiting the adsorbers in the rotor.

Abstract: The present invention is a two stage PSA process for producing high purity oxygen from a feed air stream. Water, carbon dioxide and nitrogen are removed in a first stage. An oxygen selective adsorbent is used to adsorb oxygen in the second stage. High purity oxygen product is recovered during regeneration of the second stage. Importantly, the high purity of the oxygen product is achieved without inclusion of an oxygen rinse step in the process cycle. The high purity oxygen product is obtained by collecting the middle cut of the second stage effluent stream during regeneration.

Abstract: The present invention involves a vacuum-pressure swing adsorption process for the separation of components of a fluid mixture. The process includes (a) transferring a fluid mixture through an adsorbent bed at an elevated pressure Ph so as to produce a purified product fluid; (b) venting the adsorbent bed down to an ambient fluid pressure Pa; (c) applying a vacuum force to the adsorbent bed to bring the adsorbent bed to a reduced pressure Pl; and (d) venting the adsorbent bed up to an ambient fluid pressure Pa.

Abstract: A process for producing an oxygen enriched product includes: (a) providing a gas separation apparatus having at least one bed containing a mixture of at least two different nitrogen selective adsorbents, wherein the at least one bed is free of lithium cations; (b) feeding a feed gas containing oxygen and nitrogen into the gas separation apparatus to contact the at least one bed; and (c) recovering from the gas separation apparatus the oxygen enriched product. The process is preferably performed above ambient temperature and/or in a simplified four-step cycle.

Abstract: A pressure swing adsorption process for the separation of a pressurized feed gas containing at least one more strongly adsorbable component and at least one less strongly adsorbable component.

Abstract: A process is provided for the concentration and recovery of propylene from propane by a pressure swing adsorption (PSA) process using an adsorbent comprising AlPO-14. A PSA process is used to remove propylene from a C3 hydrocarbon stream comprising propylene and propane. The PSA process of the present invention can be employed in petroleum refining and petrochemical processes to purify and separate propylene from mixtures of propylene and propane without fractionation.

Abstract: A gas separation system for separating a feed gas mixture into a first gas component and a second gas component comprises a stator, and a rotor rotatably coupled to the stator. The stator includes a first stator valve face, a second stator valve surface, and a plurality of function compartments opening into the stator valve surfaces. The rotor includes a first rotor valve surface in communication with the first stator valve surface, and a second rotor valve surface in communication with the second stator valve surface. The rotor also includes a plurality of rotor flow paths for receiving gas adsorbent material therein for preferentially adsorbing the first gas component in response to increasing pressure in the rotor flow paths in comparison to the second gas component. Each rotor flow path includes a pair of opposite ends opening into the rotor valve faces for communication with the function compartments.

Abstract: A VPSA apparatus includes a first adsorbent bed and a second adsorbent bed, a feed blower for providing a flow of a gas mixture at about atmospheric pressure to the beds, and a vacuum blower for removing a flow of gas therefrom and venting the gas to a space at atmospheric pressure. The VPSA process causes the first adsorbent bed to be poised for evacuation by the vacuum blower and concurrently, the second adsorbent bed is under vacuum conditions and is poised for pressurization by the feed blower. A single motor is coupled by a common shaft to both the feed blower and the vacuum blower and operates both. A conduit/valve arrangement is operative during at least a portion of a process time when the adsorbent beds are in pressurizing/evacuation states, respectively, to couple the feed blower to the second adsorbent bed when at vacuum and for concurrently coupling the vacuum blower to the first adsorbent bed which is to be evacuated.

Abstract: Activated carbon having a specific surface area of 700 to 1,500 m2/g, a pore volume of pores having a pore diameter of 10 nm or less of 0.20 to 0.8 cc/g, a proportion of a pore volume of pores having a pore diameter of 0.6 to 0.8 nm to a pore volume of pores having a pore diameter of 10 nm or less of 75% by volume or more, a grain bulk density of 0.4 to 1.1 g/cc, a packing density of 0.30 to 0.70 g/cc, an ash content of 1.0% or less, and a tensile strength of activated carbon grains of 30 kg/cm2 or more.

Abstract: A method of separating a first gaseous component from a gas mixture comprising the first gaseous component and a second gaseous component comprising passing the gaseous mixture into an adsorption zone containing an adsorbent material capable of preferentially adsorbing at least one of the gaseous components in the gaseous mixture, to separate the first gaseous component from the second gaseous component wherein the adsorbent material is a monolithic having a plurality of channels throughout, said channels being aligned parallel to the direction of flow of the gaseous mixture and having a wall thickness of less than 1 mm and (b) recovering the non-preferentially adsorbed gaseous component from the adsorption zone. Preferably, the adsorption zone comprises multiple layers of monolithic structures in the shape of a wheel stacked one upon the other in a direction parallel to the direction of the flow of the gaseous mixture and form by spirally winding a sheet of corrugated adsorbable material about a hub.

Abstract: A vacuum swing adsorption process is provided for the separation of propylene from a feedstream comprising propylene and propane using an adsorbent comprising AlPO-14 to produce a high purity propylene product stream at high recovery. The vacuum swing adsorption process of the present invention can be employed in a variety of petroleum refining and petrochemical processes to purify and separate propylene from mixtures of propylene and propane alone or in combination with fractionation.

Abstract: A method and plant to process a fluid comprising one or more compounds G2 having a kinetic diameter less than or equal to that of nitrogen and one or more compounds G1 having a kinetic diameter greater than or equal to that of methane. The method and plant use in combination, several adsorption and desorption stages during which a first stream F1 mainly comprising compounds G1, a second stream F2 enriched in compounds G2, a third stream F3 mainly comprising compounds G2 and a fourth stream F4 mainly comprising compounds G1 are produced. At least a fraction of stream F3 is used to flush adsorption section A1.

Abstract: A gas separation process comprising feeding a gaseous mixture comprising at least two components having different adsorption characteristics into an adsorption vessel containing at least one adsorbent material capable of preferentially adsorbing at least one of the gaseous components in the gaseous mixture and subjecting the gaseous mixture to non-cryogenic conditions which enable the preferentially adsorbable gaseous component in the gaseous mixture to adsorb onto the adsorbent material and separate from the non-adsorbed component in the gaseous mixture which pass through the adsorbent vessel wherein at least one adsorbent material in the adsorbent vessel comprises a composite particle having an inner core comprising a non-porous, non-adsorbent material and at least one outer layer comprising the adsorbent material. In another embodiment of the process of the present invention a hollow particulate adsorbent material is utilized.

Abstract: The invention relates to a process for controlling a PSA, especially VSA, plant for separating a gas stream, in particular a gas stream containing nitrogen and at least one less polar gaseous component, especially oxygen and/or hydrogen. The PSA plant operates in a production cycle and has one or more adsorbers, each production cycle comprising at least one feed step of feed duration (TA), which comprises introducing the gas stream to be separated into an adsorber; at least one production step, which comprises recovering a stream of gas produced at a prefixed production pressure (PP) and with a prefixed nominal production output (DN); and at least one pumping step of pumping duration (TP); which comprises extracting a gas stream from at least one adsorber.

Abstract: A PSA or VSA process for separating a gas flow, such as air, containing at least one first gas compound, such as nitrogen, which is preferentially adsorbed on at least one adsorbent, and at least one second gas compound, such as oxygen, which is adsorbed less preferentially on at least the one adsorbent than the first gas compound. The adsorbent used comprises particles of faujasite zeolite having a Si/Al ratio <1.5, such as a LSX zeolite, and containing 80 to 99% Li+ cations, 0.01 to 25% Na+ cations, 0.01% to 10% Mg2 cations, 0.01% to 10% Ca2+ cations and 0 to 3% K+ cations.

Abstract: A PSA process for separating a gas flow, such as air, containing a first gas compound, such as nitrogen, which is adsorbed preferentially on an adsorbent, and a second gas compound, such as oxygen, which is adsorbed less preferentially on the adsorbent than the first gas compound. The adsorbent is formed by an aggregate comprising a zeolite phase and a binder, and contains elements Si, Al, Li, Na, Mg, K and Ca, the total proportions of these elements in the adsorbent being such that the Si/Al ratio is between 1 and 2.4, the Na/Li ratio is between 0.012 and 0.300, the Mg/Li ratio is between 0.012 and 0.400, the Ca/Li ratio is between 0.012 and 0.200, and the K/Li ratio is between 0.001 and 0.060.

Abstract: A process and composition for selectively adsorbing oxygen from a gaseous mixture. The chemisorption is carried out by a porous three-dimensional transition element complex comprised of intermolecularly bound TEC units, said units further comprised of at least one multidentate ligand forming at least one five- or six-membered chelate ring on each unit.

Abstract: Upon a reduction of the production flow rate, there is added to the cycle, at an extreme pressure PM and/or Pm of the cycle substantially different from atmospheric pressure, an idle time in the course of which the adsorber (1A, 1B) is isolated. The process is used in trans-atmospheric cycles for the production of oxygen from atmospheric air.

Abstract: Substantially all of the carbon dioxide is removed from a gas containing up to about 1% by volume carbon dioxide by subjecting the gas to a pressure swing adsorption process using a two layer adsorption system, wherein the first layer contains activated alumina and the second layer is a zeolite or a combination of zeolites having a silicon to aluminum atomic ratio of at least 1.5. The process is particularly suitable for removing substantially all carbon dioxide and water vapor contained in air prior to subjecting the air to cryogenic distillation.

Abstract: A method of separating a first gaseous component from a gas mixture comprising the first gaseous component and a second gaseous component comprising passing the gaseous mixture into an adsorption zone containing an adsorbent material capable of preferentially adsorbing at least one of the gaseous components in the gaseous mixture, to separate the first gaseous component from the second gaseous component wherein the adsorbent material is a monolith having a plurality of channels throughout, the channels being aligned parallel to the direction of flow of the gaseous mixture and having a wall thickness of less than 1 mm and (b) recovering the non-preferentially adsorbed gaseous component from the adsorption zone. Preferably, the adsorption zone comprises multiple layers of monolithic structures in the shape of a wheel stacked one upon the other in a direction parallel to the direction of the flow of the gaseous mixture and form by spirally winding a sheet of corrugated adsorbable material about a hub.

Abstract: Ethene is separated from a gas mixture containing ethane by a pressure swing adsorption process carried out at a temperature in the range of about 50 to about 200° C., wherein the adsorption step of the process is conducted by passing the gas mixture through an adsorption zone containing type A zeolite whose exchangeable cations are preferably made up of at least about 60 but not more than 75% sodium ions and more than 25 and up to about 40 percent potassium ions.

Abstract: A process for the separation/recovery of gases is described where the desired component to be separated from the gaseous mixture is present in low/very low molar amount and/or low/moderate pressure, the process comprising contacting the gaseous mixture with a separation membrane unit containing high permeability/medium selectivity membranes which separate the feed stream into a permeate stream, enriched in the desired component and at a lower pressure and a retentate stream lean in the desired component and at a higher pressure. The retentate stream is made to convey its pressure to the permeate stream which then is directed to an adsorption PSA unit for further purification of the permeate stream so that the effluent stream from the PSA unit which contains the purified component has a purity of up to 99.90%.

Abstract: Pressure swing adsorption separation of a feed gas mixture, to obtain a purified product gas of the less strongly adsorbed fraction of the feed gas mixture, is performed in a plurality of preferably an even number of adsorbent beds, with each adsorbent bed communicating at its product end directly to a variable volume expansion chamber, and at its feed end by directional valves to a feed compressor and an exhaust vacuum pump. For high frequency operation of the pressure swing adsorption cycle, a high surface area layered support is used for the adsorbent. The compressor and vacuum pump pistons may be integrated with the cycle, reciprocating at twice the cycle frequency. Alternative configurations of the layered adsorbent beds are disclosed.

Abstract: A PSA process and system utilizes a combination of cyclic feed, evacuation, purge, and repressurization steps to provide a final gas product enriched in one of the feed components. The process is carried out in a simple system which utilizes a single two-way four-port valve for controlling gas flow between an adsorber vessel and a blower, and the blower is used for the introduction of feed gas into the adsorber and the evacuation of gas from the adsorber. The control of gas flow in either direction between the adsorber vessel and a product gas storage tank is accomplished by two check valves installed in parallel between the vessel and the tank.

Abstract: A dual-chambered, four-ported rotary valve with a rotatable drum having peripheral openings is used to selectively connect vacuum and/or air sources and a vent to absorption chambers in a two-bed VPSA (vacuum presssure swing absorption) system to replace separate valves and produce low cost enriched oxygen, via reduced power, increased reliability, and reduced complexity and cost.

Abstract: The strongly adsorbed component of a gas mixture is produced in enhanced purity and yield by novel PSA cycles. The basic steps of the cycles include an adsorption vessel prepressurization step, a cocurrent nonadsorbed gas production step, a cocurrent purge step with strongly adsorbed gas product and a countercurrent depressurization step which produces the strongly adsorbed gas product that is used in the cocurrent purge step. In addition to the basic steps, a first depressurization equalization step precedes or follows the cocurrent purge step and a corresponding first pressurization equalization step follows the countercurrent depressurization step. The cycle optionally includes one or two depressurization equalization steps before the cocurrent purge step and one or two corresponding pressurization equalization steps after the first pressurization equalization step.

Abstract: This process uses a pressure variation cycle, in which, at at least one instant in the cycle, a terminal of a compression machine (1, 3) is switched from a first space (A1) which is at a first pressure P1 to a second space (A2) which is at a pressure P2 significantly different from P1. The switching comprises an intermediate operation in which the terminal is brought simultaneously into communication with the first space and with the second space. The process is useful in the production of oxygen from atmospheric air by adsorption.

Abstract: According to this process, in the case of a reduction in the production rate, the maximum pressure PM of the cycle is lowered and the ratio of this maximum pressure to the minimum pressure Pm of the cycle is reduced, in particular by altering the durations of compression and decompression stages. The process is applicable to the production of oxygen at variable rate.

Abstract: A process for fabricating a gas storage and dispensing system including a dispenser container for holding a physical sorbent material having sorptive affinity for (i) a sorbable dispensing gas to be held in and subsequently selectively discharged from the dispenser container, and (ii) extraneous sorbables, in which the physical sorbent material, having extraneous sorbables sorbed thereon, is treated to desorb from the sorbent material at least part of the extraneous sorbables, prior to loading the sorbent material into a gas storage and dispensing container.

Abstract: Pressure swing adsorption (PSA) separation of a feed gas mixture is performed within an apparatus having typically a single prime mover powering a feed compressor for one or multiple rotary PSA modules in parallel, each module including a rotor with a large number of angularly spaced adsorber elements, with valve surfaces between the rotor and a stator so that individual adsorber elements are opened to compartments for staged pressurization and blowdown, with thermally boosted energy recovery from staged expansion of countercurrent blowdown and light reflux gases, and a plurality of adsorber elements opened at any instant to each compartment so that each compressor and expander stage operates under substantially steady conditions of flow and pressure.

Abstract: The present invention relates to the recovery of low purity oxygen gas from the top of an adsorber vessel into a receiver tank to be used as a purge reflux gas. Recovery of void gas results in improved process efficiency. The invention may also employ a simultaneous evacuation from the top of the adsorber to remove the lower purity void gas while the main waste evacuation step is conducted. This simultaneous co-current top void gas recovery and counter-current waste evacuation from both ends of the adsorber allows for an overall increase in product recovery of between 3-5% over conventional processes.

Abstract: High purity strongly adsorbed gas, e. g., carbon monoxide, is separated from a gas mixture containing one or more other gas components, e. g., hydrogen carbon dioxide, methane, nitrogen and possibly other impurities, by a two-phase pressure swing adsorption process carried out in one or more adsorption vessels arranged in parallel and containing adsorbent which adsorbs the strongly adsorbed gas more readily than the other components of the gas mixture. The process includes two evacuation steps and two or more purge steps.

Abstract: A vacuum pressure swing adsorbent (VPSA) system and method for separating a component from a fluid mixture and including a fluid source for introducing the mixture into the system and a supply apparatus for collecting the separated component. A pair of adsorbent bed vessels is interposed between the fluid source and the supply apparatus to adsorb and desorb a predetermined component under respective adsorption and desorption pressures characterized by a low pressure ratio and relatively high desorption pressure values. Implementation of a single-stage vacuum device made possible by the use of the high desorption pressure, results in further reduction in both equipment and operating costs.

Abstract: In an adsorptive alternating pressure process for the enrichment of air with oxygen using a molecular sieve zeolite in an adsorber, wherein adsorbed components are desorbed under a pressure below the pressure at which air separation and N.sub.2 adsorption is effected and, after desorption, the molecular sieve adsorber is at least partly returned to the air separation pressure with oxygen gas produced in countercurrent to the air separation gas flow, the improvement which comprises cooling product gas and covering the molecular sieve adsorber with the cooled product gas.

Abstract: A process for separating the components of a gas mixture in a single adsorption vessel pressure swing adsorption system including the steps: (a) cocurrently passing the gas mixture through the adsorption vessel at a desired adsorption pressure and collecting the nonadsorbed product gas in a storage vessel, (b) cocurrently depressurizing the adsorption vessel and pumping gas removed from the adsorption vessel during this step to the storage vessel, (c) regenerating the adsorbent in the adsorption vessel by countercurrently depressurizing the adsorption vessel, and (d) repressurizing the adsorption vessel to the desired adsorption pressure. Steps (a) and (b) are carried out using gas pumping or compressing devices, and the same or different gas pumping or compressing devices can be used for steps (a) and (b). Step (c) can also be carried out with the pumping device used in step (a).

Abstract: A process and apparatus for separating the components of a gas mixture by PSA in a four-vessel adsorption system operated as two pairs of adsorption vessels. The vessels of each pair are operated 180.degree. out of phase, such that one vessel of a pair is in the adsorption mode while the other vessel of the pair is undergoing adsorbent regeneration. The apparatus includes the two pairs of adsorption vessels, an intermediate gas storage reservoir which is used to temporarily store gas removed from the nonadsorbed gas outlet end of the adsorption vessels for use in various steps of the process, one gas blower and a pair of vacuum pumps. The adsorption cycle is such that the pairs of adsorption vessels are operated out of phase relative to each other and the blower and both vacuum pumps are in continuous operation throughout the process. The process and system are particularly well adapted to the separation of nitrogen from oxygen by vacuum swing adsorption.

Abstract: Air is supplied along a pipeline to an apparatus for separating an oxygen-enriched gas stream from the air by vacuum swing adsorption. The oxygen-enriched gas stream is supplied to a burner which fires into a furnace. A hot gas stream leaves the furnace through an outlet. Steam is raised from the hot gas in a waste heat boiler. Steam so raised flows through one or more of the eductors to draw through a pipeline the vacuum necessary for the operation of the vacuum swing adsorption apparatus.

Abstract: In order to provide a pressure-swing-adsorption oxygen production process which can maintain the product recovery at a high level while enhancing the oxygen productivity and reducing the unit power consumption, a pressure recovery step is carried out in which communication is provided between an outlet end of an adsorption column which has completed an adsorption step and an outlet end of an adsorption column which has completed a regeneration step, and in which gas remaining in the adsorption column which has completed the adsorption step is collected within the adsorption column which has completed the regeneration step; and simultaneously with the pressure recovery step, a gas mixture which has approximately the same composition as feed gas mixture is introduced into at least one of the adsorption column which has completed the adsorption step and the adsorption column which has completed the regeneration step through the inlet end thereof.

Abstract: Substantially all of the carbon dioxide is removed from a gas containing up to about 1% by volume carbon dioxide by subjecting the gas to a pressure swing adsorption process using as the adsorbent a single layer of zeolite having a silicon to aluminum atomic ratio in the range of 1.5 to 70. The process is particularly suitable for removing substantially all carbon dioxide and water vapor contained in air prior to subjecting the air to cryogenic distillation.

Abstract: A process for the treatment of a gaseous mixture by adsorption with variable pressure, in an adsorption installation comprising at least one adsorber. For each adsorber, there is a succession of steps defining an adsorption phase, a regeneration phase for the adsorbent comprising a depressurization step, and a pressure increase phase. The passage from one phase to the following comprises switching of at least one valve between open and closed positions. At least one valve switching is carried out according to a programmed progressive slope to control a first cocurrent decompression stage of the adsorber with transfer of gas toward a lower pressure portion of the installation. The transferred gas is sent, for at least partially balancing pressure, to another adsorber in a pressure increase phase.