The invention relates to a method for regulating a unit for separating a gas stream, having P adsorbers, where P≥2, each following a PSA-type adsorption cycle with a phase time shift, the method involving the steps of operating the unit according to the nominal cycle when the required flow rate is equal to a nominal flow rate or optionally when the required flow rate is higher than the nominal flow rate, and operating the unit according to the reduced cycle when the required flow rate is lower than or equal to a predetermined flow rate, the predetermined flow rate being lower than the nominal flow rate.

A pressure swing adsorption process (PSA) comprising the following steps: feeding an input gas containing H.sub.2, CO.sub.2 and impurities through a CO.sub.2 adsorbent material in a pressure vessel under a high pressure; withdrawing a first H.sub.2-rich product gas due to adsorption of CO.sub.2 in the adsorbent material; setting the pressure to an intermediate pressure causing the adsorbent material release a second gas stream; passing a CO.sub.2-rich purge stream through the adsorbent material, obtaining a purge gas; setting the pressure to a sub-atmospheric low pressure, so that a CO.sub.2-rich product gas is released under vacuum by the adsorbent material; re-pressurizing the vessel to said high pressure; said steps being performed cyclically in a pressure vessel or in a plurality of parallel pressure vessels of a multiple vessel setup.

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.

A gas separation and recovery method is provided. Based on the fact that a gas adsorbent has differing adsorption and desorption characteristics depending on the affinities and pressures of gas species, and gases of different species are desorbed at different timings, a target gas component is separated and recovered from a source gas by a pressure swing adsorption process in such a manner that a desorption step is divided into, for example, two time periods and desorbed gases are recovered separately in the respective time periods. In this manner, when gas 1 and gas 2 having different desorption timings are adsorbed to an adsorbent, a gas rich in gas 1, and a gas rich in gas 2 may be recovered separately from each other. Thus, it becomes possible to separate and recover selectively a target gas component with high concentration.

A piece of equipment commonly used in many petrochemical and refinery processes is a pressure swing adsorption (PSA) unit. A PSA unit may be used to recover and purify hydrogen process streams, such as from hydrocracking and hydrotreating process streams. Aspects of the present disclosure are directed to monitoring PSA unit processes for potential and existing issues, providing alerts, and/or adjusting operating conditions to optimize PSA unit life. There are many process performance indicators that may be monitored including, but not limited to, flow rates, chemical analyzers, temperature, and/or pressure. In addition, valve operation may be monitored, including opening speed, closing speed, and performance. The system may adjust one or more operating characteristics to decrease the difference between the actual operating performance in the recent and the optimal operating performance.

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.

The present invention relates to a process for processing a gas mixture comprising methane, carbon dioxide, carbon monoxide, hydrogen, nitrogen, argon and traces of olefins and oxygenates. Methane, carbon dioxide and carbon monoxide, and optionally hydrogen, can be recovered from the gas mixture in a very efficient way.

A gas separation and recovery method is provided. Based on the fact that a gas adsorbent has differing adsorption and desorption characteristics depending on the affinities and pressures of gas species, and gases of different species are desorbed at different timings, a target gas component is separated and recovered from a source gas by a pressure swing adsorption process in such a manner that a desorption step is divided into, for example, two time periods and desorbed gases are recovered separately in the respective time periods. In this manner, when gas 1 and gas 2 having different desorption timings are adsorbed to an adsorbent, a gas rich in gas 1, and a gas rich in gas 2 may be recovered separately from each other. Thus, it becomes possible to separate and recover selectively a target gas component with high concentration.

A piece of equipment commonly used in many petrochemical and refinery processes is a pressure swing adsorption (PSA) unit. A PSA unit may be used to recover and purify hydrogen process streams, such as from hydrocracking and hydrotreating process streams. Aspects of the present disclosure are directed to monitoring PSA unit processes for potential and existing issues, providing alerts, and/or adjusting operating conditions to optimize PSA unit life. There are many process performance indicators that may be monitored including, but not limited to, flow rates, chemical analyzers, temperature, and/or pressure. In addition, valve operation may be monitored, including opening speed, closing speed, and performance. The system may adjust one or more operating characteristics to decrease the difference between the actual operating performance in the recent and the optimal operating performance.

The present invention relates to a process for processing a gas mixture comprising methane, carbon dioxide, carbon monoxide, hydrogen, nitrogen, argon and traces of olefins and oxygenates. Methane, carbon dioxide and carbon monoxide, and optionally hydrogen, can be recovered from the gas mixture in a very efficient way.