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.

According to an exemplary embodiment of the present invention, a pressure swing adsorption process of a hydrogen production system is provided. The hydrogen production system includes a desulfurization process for removing sulfur components from raw natural gas; a reforming reaction process for producing a reformed gas containing hydrogen generated by the reaction of natural gas through the desulfurization process and steam; and a pressure swing adsorption process of concentrating the hydrogen using a pressure swing adsorption from the reformed gas. In a desorption step of the pressure swing adsorption process, a cocurrent depressurization and a countercurrent depressurization are simultaneously performed.

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.

A system for pressure swing adsorption including: a plurality of beds each performing at least one of an adsorbing process, a pressure equalizing process, a vacuum process, or a pressurizing process; a supply valve provided in each of the beds and connected to a mixed gas supply unit to supply a mixed gas to the bed; a discharge valve provided in each of the beds and connected to a hydrogen gas discharge unit to discharge hydrogen generated in the bed; a vacuum valve provided in each of the beds and connected to a vacuum pump so as to be open to the vacuum pump during the vacuum process of the bed; and a control unit that controls the supply valve, the discharge valve, and the vacuum valve to allow each of the beds to perform the adsorbing process, the pressure equalizing process, the vacuum process, or the pressurizing process.

The present invention relates to an integrated method and apparatus for providing a synthesis gas to a cryogenic separation unit installed for separating synthesis gas into products selected from carbon monoxide, crude hydrogen, methane-rich fuel and syngas with a particular H.sub.2:CO ratio. More specifically, the invention relates to the purification of synthesis gas routed to a downstream cryogenic separation unit and minimizing temperature disturbances in the separation unit.

The present invention relates to a process cycle that allows for the stable production of mid-range purity oxygen from air, using traditional system designs. Typical cycles have a limited production benefit when generating O.sub.2 at lower than 90% purity, however they suffer a production loss at higher purity. The process cycles of the invention are capable of producing significantly more contained O.sub.2 at a lower purity. In addition to enhanced production capacity, lower power consumed per mass of product and more stable product purity and flow are realized by the process of the invention compared to traditional alternatives.

A pressure swing adsorption gas production device that enables performing a desorption process in adsorption towers is provided. The device includes an off gas discharge route connected to the adsorption towers, a membrane separation unit with a separation membrane allowing miscellaneous gas in the off gas discharge route to pass faster than purification target gas, an off gas tank, and a pressure boosting unit that raises the pressure of and supplies the off gas to the membrane separation unit. The off gas tank and the pressure boosting unit are upstream of the membrane separation unit. The device includes a recycle gas return route via which some recycle gas is returned to the source gas supply route. The operation control unit adjusts the off gas adjustment unit so the off gas discharge flow rate is a flow rate where the amount of off gas discharged from one adsorption tower during the desorption process is equivalent to the amount of off gas discharged from the off gas tank when the one adsorption tower starts the desorption process until another starts the desorption process.

Provided is a pressure swing adsorption type hydrogen manufacturing apparatus that can improve the product recovery rate in a state where the purity of the product is kept from being reduced. A process control unit P controls operation of adsorption towers 1 that generate a product gas by adsorbing, using adsorbents, adsorption target components other than hydrogen components from a source gas, in a state where an adsorption process, a pressure-equalization discharge process, a desorption process, and a pressure-restoration process are successively repeated. The process control unit is configured to control operation of the adsorption towers 1 in such a manner that a prior pressure-equalization process of supplying gas inside an adsorption tower 1 undergoing the pressure-equalization discharge process to an adsorption tower 1 undergoing the pressure-restoration process is performed in an initial stage of a unit processing period, a subsequent pressure-equalization process of supplying gas inside the adsorption tower 1 undergoing the pressure-equalization discharge process to an adsorption tower 1 undergoing the desorption process is performed in a final stage of the unit processing period, a pressurization process of introducing a product gas H to perform pressurization is performed, as the pressure-restoration process, subsequently to the prior pressure-equalization process, and the pressurization process is performed while overlapping with the subsequent pressure-equalization process.

A process of treating a natural gas stream is provided comprising sending natural gas stream through a first adsorbent bed to remove water and heavy hydrocarbons (C8+) to produce a partially treated gas stream in which the first adsorbent bed is regenerated by a temperature swing adsorption process and then sending the partially treated gas stream through a second adsorption bed to remove carbon dioxide and lighter hydrocarbons (C7) to produce a purified natural gas stream wherein said second adsorption bed is regenerated by a temperature pressure swing adsorption process.