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.

An integrated fuel combustion system with gas separation (adsorptive, absorptive, membrane or other suitable gas separation) separates a portion of carbon dioxide from a combustion gas mixture and provides for recycle of separated carbon dioxide to the intake of a fuel combustor for combustion. A process for carbon dioxide separation and recycle includes: admitting combustion gas to an adsorptive gas separation system contactor containing adsorbent material; adsorbing a portion of carbon dioxide; recovering a first product stream depleted in carbon dioxide for release or use; desorbing carbon dioxide from the adsorbent material and recovering a desorbed second product stream enriched in carbon dioxide for sequestration or use; admitting a conditioning and/or desorption fluid into the contactor and desorbing a second portion of carbon dioxide to recover a carbon dioxide enriched conditioning stream; and recycling a portion of the carbon dioxide enriched conditioning stream to an inlet of fuel combustor to pass through the fuel combustor for combustion.

In a method of operating an adsorption apparatus including a plurality of adsorption beds each packed with a physical adsorbent, when an adsorption step is performed in a part of the adsorption beds and another adsorption bed is to be regenerated, after the adsorption target component adsorbed on the physical adsorbent is desorbed, a gas for cooling is caused to flow through the another adsorption bed so that the another adsorption bed is cooled until an outlet temperature of the another adsorption bed reaches a temperature set in advance. Further, the cooled adsorption bed stands by for switching to the adsorption step while a gas for standby for maintaining a cooled state is caused to flow through the cooled adsorption bed.

Provided herein is a method for improving a gas recovery rate during generation of a high-purity gas. The method includes providing three or more adsorption towers filled with an adsorbent that adsorbs an adsorption target gas. Performing a pressure lowering equalization process in a first adsorption tower in which an adsorption process has been finished, and in a source gas supply state in which a source gas is supplied to at least a second adsorption tower in which a pressure increasing equalization process has been finished and the adsorption process is to be subsequently performed; and transferring a non-adsorbed gas from an upper portion of the first adsorption tower to the upper portion of the second adsorption tower, thereby performing an adsorption and pressure lowering equalization process in the first adsorption tower and an adsorption and pressure increasing equalization process in the second adsorption tower.

Adsorbers have many purposes in chemical, gas-processing, and petrochemical plants. Adsorbers may be used to remove components from gas streams. Adsorbers may be subjected to various issues, including but not limited to moisture breakthrough, spent catalyst, too high or too low pressure drop, over or under heating, over or under cooling, too high or too low flow rates, which can affect their performance or result in a shutdown of the adsorbers. Monitoring the adsorbers and the processes using adsorbers may be performed to determine if the adsorbent bed is reaching saturation, other problems are occurring, or if equipment failures are imminent. Monitoring also helps to predict behavior or problems in different adsorbers used in the same plant or in other plants and/or processes.

This invention uses a fixed-bed adsorber, interchangeably called a capacitor herein, to process the product stream coming out of a regenerable adsorption system such as a temperature swing adsorption system (TSA) or pressure swing adsorption system (PSA). The fluid stream coming out of this fixed-bed capacitor will have a more uniform composition than the one entering the adsorption system or the capacitor. The fixed-bed adsorber operates in a once-through non-cyclic manner, similar to a conventional fixed bed reactor or adsorber.

Provided is a canister that makes it possible to reduce production costs. One aspect of the present disclosure is a canister. The canister includes an outer case including a charge port that takes in an evaporated fuel, a purge port that discharges the evaporated fuel, and an atmosphere port open to the atmosphere, an inner case arranged inside the outer case, the inner case having an inner space to which the atmosphere port is connected, a first adsorption chamber arranged in the inner space of the inner case, and a second adsorption chamber arranged between the first adsorption chamber and the atmosphere port in a flow path of the evaporated fuel in the inner space of the inner case. A cross-sectional area perpendicular to a gas flow direction in the second adsorption chamber and a cross-sectional area perpendicular to a gas flow direction in the first adsorption chamber are different.

A gas stream is purified by a TSA adsorption scheme including at least two adsorbers following, in an offset manner, a cycle including an adsorption phase, and a subsequently, a regeneration phase. The regeneration phase includes a depressurization step, a pre-regeneration step and a regeneration step. A gas circulator is used to circulate the gas within the adsorber in the pre-regeneration step in a closed loop while the circulating gas is heated with a heater.

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.

A three-product PSA system which produces three product streams from a feed gas mixture comprising a light key component, at least one heavy key component, and at least one intermediate key component is described. The three-product PSA system produces a high pressure product stream enriched in the light key component, a low pressure tail gas stream enriched in the at least one heavy key component, and an intermediate pressure vent gas stream enriched in the at least one intermediate key component.