A system for processing a gas stream can include a physical solvent unit, an acid gas removal unit upstream or downstream of the physical solvent unit, and an LNG liquefaction unit downstream of the acid gas removal unit. The physical solvent unit is configured to receive a feed gas, remove at least a portion of any C.sub.5+ hydrocarbons in the feed gas stream using a physical solvent, and produce a cleaned gas stream comprising the feed gas stream with the portion of the C.sub.5+ hydrocarbons removed. The acid gas removal unit is configured to receive the cleaned gas stream, remove at least a portion of any acid gases present in the cleaned gas stream, and produce a treated gas stream. The LNG liquefaction unit is configured to receive the treated gas stream and liquefy at least a portion of the hydrocarbons in the treated gas stream.

A composition for controlling ambient humidity within 45%˜55%. The composition includes at least one organic acid salt, at least one of polyol and water. The organic acid salt includes at least one of sodium lactate, potassium lactate and sodium formate. The count of carbon in the polyol is not greater than 5. The weight percentage of the organic acid salt in the composition is 30.6%-58.8%. The weight percentage of the polyol in the composition is 9.3%-26.7%. The composition can control the ambient humidity within 45%˜55% without the need to pre-adjust the objective space. The composition has a large capacity of moisture absorption and desorption, and can quickly achieve the desired humidity in the objective environment.

Disclosed is a process for regenerating a hybrid solvent used to remove contaminants from a fluid stream and to provide an improved yield of purified fluid. Said process comprises at least one purification unit (12) and at least one regeneration unit (40) wherein condensed water (72) from the regeneration unit is combined with the regenerated lean hybrid solvent (55) prior to reuse in the purification unit and none of the condensed water is recycled into the regeneration unit.

A humidity control device includes: a storage unit that stores hygroscopic liquid that contains a hygroscopic substance; a vent that is provided in the storage unit; absorption means by which air and the hygroscopic liquid are brought into contact with each other and moisture contained in the air is absorbed by the hygroscopic liquid; an ultrasonic wave generation unit that irradiates at least a part of the hygroscopic liquid, which has absorbed the moisture, with an ultrasonic wave; and removal means by which an atomized droplet that is generated is removed from the hygroscopic liquid that has absorbed the moisture, in which the storage unit suppresses an outflow of a coarse droplet whose particle size is larger than that of the atomized droplet.

Disclosed is a carbon dioxide absorbent and a carbon dioxide separation method using the same that greatly reduces energy consumption due to a small amount of latent heat required in regeneration of absorbents, enhances CO.sub.2 absorption rate, undergoes almost no thermal denaturation even at high temperatures while absorbing carbon dioxide, and results in a considerable reduction of the cost associated with absorption of carbon dioxide.

The invention is directed to a method for electrochemically reducing carbon dioxide, and an apparatus for performing the method.

The method of the invention comprises: a) contacting a carbon dioxide-containing gas stream with a capture solvent, thereby absorbing carbon dioxide from the carbon dioxide-containing gas stream to form a carbon dioxide-rich capture solvent; b) introducing at least part of the carbon dioxide-rich capture solvent into a cathode compartment of an electrochemical cell; c) applying an electrical potential between an anode and a cathode in the electrochemical cell sufficient for the cathode to reduce carbon dioxide into a reduced carbon dioxide product or product mixture in the carbon dioxide-rich capture solvent, thereby providing a carbon dioxide-poor capture solvent; and d) collecting the reduced carbon dioxide product or product mixture,
wherein the anode is separated from the cathode by a semi-permeable separator, thereby forming a cathodic compartment and an anodic compartment, and wherein the absolute pressure of the carbon dioxide-containing gas stream is 20-200 bar.

A system for processing a gas stream can include a physical solvent unit, an acid gas removal unit upstream or downstream of the physical solvent unit, and an LNG liquefaction unit downstream of the acid gas removal unit. The physical solvent unit is configured to receive a feed gas, remove at least a portion of any C.sub.5+ hydrocarbons in the feed gas stream using a physical solvent, and produce a cleaned gas stream comprising the feed gas stream with the portion of the C.sub.5+ hydrocarbons removed. The acid gas removal unit is configured to receive the cleaned gas stream, remove at least a portion of any acid gases present in the cleaned gas stream, and produce a treated gas stream. The LNG liquefaction unit is configured to receive the treated gas stream and liquefy at least a portion of the hydrocarbons in the treated gas stream.

A gas treatment method includes an absorption step in which a gas to be treated containing an acidic compound, such as carbon dioxide, is brought into contact, in an absorber, with a treatment liquid that absorbs the acidic compound; and a regeneration step in which the treatment liquid, having the acidic compound absorbed therein, is sent to a regenerator, and the treatment liquid is then heated to separate the acidic compound from the treatment liquid. In the regeneration step, a gas almost insoluble to the treatment liquid, such as hydrogen gas, is brought into contact with the treatment liquid.

The invention pertains to processes for separating water from air. The processes may employ using an LCST solution with or without subsequent reverse osmosis, nanofiltration, or ultrafiltration.

Within a glycol contactor, a glycol stream is contacted with a wet gas stream including water in order to transfer at least a portion of the water from the wet gas stream to the glycol stream. The glycol stream entering the glycol contactor includes a mixture of triethylene glycol and tetraethylene glycol. The glycol stream exiting the glycol contactor includes the portion of the water from the wet gas stream. The glycol stream exiting the glycol contactor is flowed to a glycol regeneration system. By the glycol regeneration system and using a solvent including iso-octane, the glycol stream is fractionated to remove the portion of the water from the glycol stream. The fractionated glycol stream is recycled to the glycol contactor.