A process is provided to treat a natural gas stream by removing heavier hydrocarbons comprising C5, C6 and heavier hydrocarbons. The process involves sending a natural gas stream through an adsorbent bed to remove heavier hydrocarbons and producing a product stream comprising C1 to C4 hydrocarbons. A portion of the product stream is sent through a regeneration heater to produce a heated regeneration gas stream which is sent through the adsorbent bed to desorb the heavier hydrocarbons. Then the regeneration gas stream is cooled and sent to a separation unit such as a distillation column to divide the regeneration gas stream into a liquid stream comprising heavier hydrocarbons and a recovered regeneration gas stream.

Provided is a carbon dioxide removal apparatus that enables determination of whether or not carbon dioxide has desorbed from an adsorbent without using a carbon dioxide sensor. A carbon dioxide removal apparatus includes a carbon dioxide adsorption module, a first valve provided in an intake part of the carbon dioxide adsorption module, a second valve provided in a discharge part of the carbon dioxide adsorption module, a third valve connected to the discharge part, a vacuum pump connected to the carbon dioxide adsorption module via the third valve, and a controller. The carbon dioxide adsorption module includes a pressure meter and an adsorbent, and the controller is configured to perform, based on a pressure measured by the pressure meter, at least one of determining whether carbon dioxide has desorbed from the adsorbent or detecting an abnormality.

An activated carbon device for adsorbing solvent from a flow of air is regenerated by feeding heated inert gas to the activated carbon and by applying a reduced pressure to the heated activated carbon.

A system and method for optimizing operation of a rotating packed bed desorber or regenerator wherein a rich solvent is input and CO2 product and lean solvent are output includes collecting condensed water from a regeneration section of a rotating packed bed desorber system. The collected condensed water is then repressurized and reheated to generate steam and the steam is injected into the rotating packed bed desorber or regenerator as stripping vapors while heating rich solvent.

A device for cleaning air laden with CO2 present in an enclosed space, including at least one adsorption device for adsorbing CO2 from the air supplied to the adsorption device, a desorption device associated with the adsorption device for desorbing adsorbed CO2, and a removal device for removing the desorbed CO2.

An exemplary single bed reversing blower adsorption based air separation unit is configured to follow the O.sub.2 load placed thereon by adjusting flow rates therethrough and power consumption. At least one and preferably multiple pressure sensors sense O.sub.2 pressure within an O.sub.2 storage region downstream of an adsorber vessel. These sensed pressures are utilized to generate control signals controlling flow rates at locations upstream of the compressor, such as at a reversible blower and an output compressor. Control loops for the blower and the compressor are independent of each other and have different time constants. Effective following of the O.sub.2 load is thus achieved without driving the air separation unit into operational conditions outside of design and also maintaining optimal power consumption for the O.sub.2 produced, such that efficiency is maintained over a large turndown ratio.

A system for recovering nitrogen during regeneration of a treater, the system including an adsorbent bed downstream of the treater, wherein the adsorbent bed comprises an adsorbent operable to adsorb at least one impurity from a treater bed regeneration effluent stream comprising nitrogen to provide a nitrogen product having a higher nitrogen purity than a nitrogen purity of the treater bed regeneration effluent stream. A method for recovering nitrogen during regeneration of a treater is also provided.

A process for treating a natural gas stream comprising sending said gas stream through at least one multi-layered adsorbent bed comprising at least one layer of an adsorbent preferentially adsorbing C8+ hydrocarbons and aromatics over other impurities, at least one layer of a zeolite preferentially adsorbing carbon dioxide over other impurities and at least one layer of a zeolite preferentially removing C7 hydrocarbons over other impurities to produce a gas stream comprising methane.

An evaporative emission control canister system comprises an initial adsorbent volume having an effective incremental adsorption capacity at 25 C. of greater than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, and at least one subsequent adsorbent volume having an effective incremental adsorption capacity at 25 C. of less than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, an effective butane working capacity (BWC) of less than 3 g/dL, and a g-total BWC of between 2 grams and 6 grams. The evaporative emission control canister system has a two-day diurnal breathing loss (DBL) emissions of no more than 20 mg at no more than 210 liters of purge applied after the 40 g/hr butane loading step.

A method of providing a breath to a human patient. The patient has a patient connection connected, by a patient circuit, to a ventilator having a first ventilator connection and a different second ventilator connection. Each of the first and second ventilator connections are in fluid communication with the patient circuit. The method includes identifying, with the ventilator, initiation of an inspiratory phase of the breath, delivering a bolus of oxygen to the first ventilator connection before or during the inspiratory phase, and delivering breathing gases comprising air to the second ventilator connection during the inspiratory phase. The ventilator isolates the bolus of oxygen delivered to the first ventilator connection from the breathing gases delivered to the second ventilator connection.