We provide a method for removing contaminants from a gas, comprising: alternating input of the gas between two or more beds of adsorbent particles that comprise zeolite SSZ-36, zeolite SSZ-39, or zeolite SSZ-45; wherein the gas contacts one of the beds during an adsorption and a tail gas is simultaneously vented from another of the beds by desorption; wherein a contacting pressure is from about 345 kPa to about 6895 kPa and produces a product gas containing no greater than about 2 mol % carbon dioxide, at least about 10 wppm water, at least about 65 mol % of methane recovered from the feed gas, and at least about 25 mol % of ethane recovered from the feed gas; and wherein the tail gas is vented from the feed end of the beds. We also provide a method for removing a contaminant from a gas, wherein the gas contains hydrogen sulfide.

Converting carbon sources that would otherwise be vented to the atmosphere or discarded as waste to one or more products. Carbon sources may be dilute carbon containing streams that are purified to from about 90 vol.-% to about 95 vol.-% carbon compound. In certain aspects, also disclosed are the processes for producing desirable products, such as ethylene, from industrial waste streams.

Provided are apparatus and systems for performing a swing adsorption process. This swing adsorption process may involve passing streams through adsorbent bed units to remove contaminants, such as water, from the stream. As part of the process, the adsorbent bed unit is purged with a purge stream that is provided at a temperature less than 450 F. The de-contaminated stream may be used with a liquefied natural gas (LNG) plant or other subsequent process requiring a de-contaminated stream. The swing adsorption process may involve a combined TSA and PSA process, which is utilized to remove contaminants from the feed stream.

Provided are apparatus and systems for performing a swing adsorption process. This swing adsorption process may involve passing streams through adsorbent bed units to treat the feed stream to form a stream that complies with nitrogen rejection specifications. The process may involve using at least a portion of the nitrogen rejection process product streams as a purge for the swing adsorption process.

An embodiment of this invention provides a method of effectively producing propylene by separating reaction products obtained by dehydrogenating propane-containing feedstock, using an adsorption process in lieu of conventional low-temperature separation processes.

A carbon dioxide recovery apparatus has a separator which separates carbon dioxide from a gas by utilizing adsorption and desorption of carbon dioxide to and from an adsorbent caused by pressure fluctuation, the separator including a pressurizer which pressurizes the gas to a pressure that the adsorbent is capable of adsorbing carbon dioxide, and has a dryer having a hygroscopic agent for drying the gas. A regeneration system supplies the residual gas discharged from the separator to the dryer as a regeneration gas for regenerating the hygroscopic agent in the dryer, and the regeneration gas to be supplied to the dryer is heated by an energy converter by utilizing a pressure of a post-regeneration gas discharged by the regeneration of the hygroscopic agent.

An oxygen separator for generating an oxygen-enriched gas from an oxygen comprising gas, said oxygen separator comprising: a) an oxygen separator device comprising i) a sorbent material for sorbing at least one component of the oxygen comprising gas; and ii) at least two controllable interfaces, comprising a first controllable interface and a second controllable interface, for controlling the communication of gas between the inside and the outside of the oxygen separator device, b) a processor for controlling the oxygen separator such that a plurality of phases are sequentially carried, amongst them a purging phase; wherein the processor is configured to control the at least two controllable interfaces such that a flow of gas is generated between the first controllable interface and the second controllable interface during at least the purging phase, wherein the second controllable interface is located and/or controlled such that it controls the fluidic coupling between the inside of the oxygen separator device and a volume of non-oxygen-enriched gas during the purging phase.

Biogas containing H.sub.2S and CO.sub.2 is upgraded by removing H.sub.2S using PTSA and CO.sub.2 using two stages of gas separation membranes. The first stage permeate may optionally be used a regeneration gas stream. The second stage permeate may optionally be used a cool down gas stream. The PTSA unit includes two or more adsorbent beds each selective for water, VOCs, and H.sub.2S over CO.sub.2 and for H.sub.2S over methane.

We provide a method for removing contaminants from a gas, comprising: alternating input of the gas between two or more beds of adsorbent particles that comprise zeolite SSZ-36, zeolite SSZ-39, or zeolite SSZ-45; wherein the gas contacts one of the beds during an adsorption and a tail gas is simultaneously vented from another of the beds by desorption; wherein a contacting pressure is from about 345 kPa to about 6895 kPa and produces a product gas containing no greater than about 2 mol % carbon dioxide, at least about 10 wppm water, at least about 65 mol % of methane recovered from the feed gas, and at least about 25 mol % of ethane recovered from the feed gas; and wherein the tail gas is vented from the feed end of the beds. We also provide a method for removing a contaminant from a gas, wherein the gas contains hydrogen sulfide.

Separating a starting gas mixture using pressure swing adsorption. In this, at least part of a low-pressure extraction flow from the pressure swing adsorption is subjected to a thermal separation, wherein a return fraction is formed in the thermal separation which is returned to the pressure swing adsorption separation. In the thermal separation, counterflow cooling takes place to obtain a two-phase mixture, wherein at least part of the two-phase mixture is subjected to phase separation to obtain a gas phase and a condensate. At least a part of the gas phase is used to form the return fraction, and counterflow cooling is carried out using at least a part of the gas phase and at least a part of one or more fluid flows which are formed by expansion of at least a part of the liquid phase.