The present invention relates to an intensified 5-bed and 6-bed PSA process cycles features, as well as fast rate adsorbents that enable the intensified PSA system to meet cost and performance target are identified. The proposed capital efficient H.sub.2PSA system offers opportunity to reduce PSA capital expenditure by ten percent (10%).

A method for producing oxygen from air using vacuum swing adsorption by means of a unit including at least two adsorbers each following, with an offset a pressure cycle, with a decompression step including at least a co-current first decompression sub-step for the partial balancing of pressure with the other adsorber which is performing counter-current recompression by means of a balancing valve, and, at least for one cycle out of three, a dead time sub-step which succeeds the first decompression sub-step, the method including a pressure of X bar at the end of the first decompression sub-step for the cycles that do not have a dead time sub-step, and a pressure of X bar at the end of the dead time sub-step, opening the balancing valve identically during the first decompression sub-step and the dead time sub-step, for the cycles that do have a dead time sub-step.

Methods and systems for capture of CO.sub.2 from a hydrated gaseous stream are described. Systems can be utilized for direct air capture of CO.sub.2 and incorporate a low energy temperature-vacuum swing adsorption (TVSA) process. A TVSA process can include a multi-step CO.sub.2 capture bed regeneration process that includes depressurization of the bed, heating of the bed, venting and purging of the bed, and cooling of the bed. Multiple beds can be cycled between CO.sub.2 capture and regeneration, during which captured CO.sub.2 is recovered. Off-gas from a CO.sub.2 capture bed can be used in regenerating a parallel bed for increased efficiency.

The present invention relates to an intensified 5-bed and 6-bed PSA process cycles features, as well as fast rate adsorbents that enable the intensified PSA system to meet cost and performance target are identified. The proposed capital efficient H.sub.2PSA system offers opportunity to reduce PSA capital expenditure by ten percent (10%).

A method for producing oxygen from air using vacuum swing adsorption by means of a unit comprising at least two adsorbers each following, with an offset a pressure cycle, with a decompression step comprising at least a co-current first decompression sub-step for the partial balancing of pressure with the other adsorber which is performing counter-current recompression by means of a balancing valve, and, at least for one cycle out of three, a dead time sub-step which succeeds the first decompression sub-step, the method including a pressure of X bar at the end of the first decompression sub-step for the cycles that do not have a dead time sub-step, and a pressure of X bar at the end of the dead time sub-step, opening the balancing valve identically during the first decompression sub-step and the dead time sub-step, for the cycles that do have a dead time sub-step.

Methods and systems for capture of CO.sub.2 from a hydrated gaseous stream are described. Systems can be utilized for direct air capture of CO.sub.2 and incorporate a low energy temperature-vacuum swing adsorption (TVSA) process. A TVSA process can include a multi-step CO.sub.2 capture bed regeneration process that includes depressurization of the bed, heating of the bed, venting and purging of the bed, and cooling of the bed. Multiple beds can be cycled between CO.sub.2 capture and regeneration, during which captured CO.sub.2 is recovered. Off-gas from a CO.sub.2 capture bed can be used in regenerating a parallel bed for increased efficiency.

A method for separating ozone from a mixture of oxygen and ozone by feeding the mixture to at least one adsorbent bed containing an adsorbent material for adsorbing ozone. The adsorbent bed can be one of four adsorbent beds in a continuous adsorption cycle for producing ozone recycling the non-adsorbed oxygen together with make-up oxygen to the ozone generator or using it as a purge gas. An external purge gas is used to desorb the ozone to the customer process. With four beds present, for most of the time, two beds are in adsorption mode while the other two beds are in regeneration/production mode.

A method for separating ozone from a mixture of oxygen and ozone by feeding the mixture to at least one adsorbent bed containing an adsorbent material for adsorbing ozone. The adsorbent bed can be one of four adsorbent beds in a continuous adsorption cycle for producing ozone recycling the non-adsorbed oxygen together with make-up oxygen to the ozone generator or using it as a purge gas. An external purge gas is used to desorb the ozone to the customer process. With four beds present, for most of the time, two beds are in adsorption mode while the other two beds are in regeneration/production mode.

This invention concerns a method for recovering carbon monoxide and carbon dioxide from Fischer-Tropsch off-gas by feeding Fischer-Tropsch off-gas through a column comprising an adsorbent bed, and discharging effluent, optionally rinsing the column and the adsorbent bed by feeding carbon dioxide and discharging effluent until at least 60% of the carbon monoxide that was present in the bed is discharged, pressurizing the column and adsorbent bed with carbon dioxide, rinsing the column and the adsorbent bed by feeding carbon dioxide, until at least 60% of the methane and optionally an amount equal to at least 50% of the carbon dioxide present at the commencement of this rinsing step is discharged, rinsing the column and adsorbent bed by feeding a mixture of hydrogen and nitrogen, pressurizing the column and adsorbent bed by feeding a mixture of hydrogen and nitrogen. With this method a feed comprising at least 50 vol % carbon monoxide can be produced. Furthermore, methane and carbon dioxide at a high pressure can be recovered from the Fischer-Tropsch gas. This can be fed to a gasifier or a reformer. In a preferred embodiment a gas comprising at least 80 vol % hydrogen is produced as well.

Disclosed are methods for removing acid gas from a feed stream of natural gas including acid gas, methane and ethane. The methods include alternating input of the feed stream between at least two beds of adsorbent particles comprising zeolite SSZ-13 such that the feed stream contacts one of the at least two beds at a given time in an adsorption step and a tail gas stream is simultaneously vented from another of the at least two beds in a desorption step. The contact occurs at a feed pressure of from about 50 to about 1000 psia for a sufficient period of time to preferentially adsorb acid gas from the feed stream. A product gas stream is produced containing no greater than about 2 mol % carbon dioxide and at least about 65 mol % of methane recovered from the feed stream and at least about 25 mol % of ethane recovered from the feed stream. The feed stream is input at a feed end of each bed. The product gas stream is removed from a product end of each bed. The tail gas stream is vented from the feed end of each bed. The methods require lower vacuum power consumption and allow improved hydrocarbon recoveries compared with known methods.