A method and apparatus for purifying gas where gas is treated in a multistage treatment having at least two ejector stages, a motive medium including liquid, steam or gaseous agent at high pressure injected by an ejector of the ejector stage, and the gas is sucked into the same ejector and mixed with the motive medium for forming a mixture, at least a part of gas and/or liquid phase of the mixture is supplied to a second ejector stage having so that a second motive medium which includes liquid, steam or gaseous agent is injected to the ejector and the gas and/or the liquid phase is sucked into the same ejector in which the gas and/or liquid phase is mixed with the second motive medium for forming a second mixture, at least one of the mixtures includes an additive for removing impurities of the gas, and a purified gas is formed.

Puncture elements and methods for using the same are disclosed. The puncture elements according to the disclosed concept include a cutting edge or a sharp and are composed of a mineral loaded polymer. The minerals of the mineral loaded polymer include an active agent, such as a desiccant. Optionally, the puncture elements are used to puncture a cover (e.g., foil seal) of a package.

A fuel cell system for removing CO.sub.2 from anode exhaust gas includes a fuel cell having an anode that outputs anode exhaust including H.sub.2, CO, CO.sub.2, and water; a shift reactor that receives a first portion of the anode exhaust and performs a water-gas shift reaction to produce an output stream primarily including H.sub.2 and CO.sub.2; an anode gas oxidizer (AGO); and an absorption system including an absorber column that absorbs the CO.sub.2 from the output stream in a solvent and outputs a resultant gas including H.sub.2 and a hydrocarbon that is at least partially recycled to the anode, and a stripper column that regenerates the solvent and outputs a CO.sub.2-rich stream. The AGO is configured to oxidize at least a portion of the CO.sub.2-rich stream and an AGO input stream that includes one of a second portion of the anode exhaust or a portion of the output stream.

A hydrophilized material has a surface provided with surface roughness that arithmetic mean roughness is 0.3 m to 1.0 m and mean width of roughness profile elements is 0.1 mm or less. A hydrophilized member that contacts a liquid is at least partially made of the hydrophilized material. The hydrophilized member is applicable to a gas-liquid contact apparatus having a gas-liquid contact section, a liquid supply system, and a gas supply system, to constitute the gas-liquid contact section as a packing element. Wettability imparted due to the surface roughness is exhibited continuously.

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.

An absorbent for selective removal of hydrogen sulfide over carbon dioxide from a fluid stream comprises an aqueous solution of a) a tertiary amine, b) a sterically hindered secondary amine of the general formula (I)

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in which R.sub.1 and R.sub.2 are each independently selected from C.sub.1-4-alkyl and C.sub.1-4-hydroxyalkyl; R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently selected from hydrogen, C.sub.1-4-alkyl and C.sub.1-4-hydroxyalkyl, with the proviso that at least one R.sub.4 and/or R.sub.5 radical on the carbon atom bonded directly to the nitrogen atom is C.sub.1-4-alkyl or C.sub.1-4-hydroxyalkyl when R.sub.3 is hydrogen; x and y are integers from 2 to 4 and z is an integer from 1 to 4; where the molar ratio of b) to a) is in the range from 0.05 to 1.0, and c) an acid in an amount, calculated as neutralization equivalent relative to the protonatable nitrogen atoms in a) and b), of 0.05 to 15.0%. One preferred amine of the formula I is 2-(2-tert-butylaminoethoxy)ethanol. The absorbent allows a defined H.sub.2S selectivity to be set at pressures of the kind typical in natural gas processing.

A carbon dioxide removal system includes: an absorption system including a first absorption stage and a second absorption stage. The first absorption stage includes: a first compressor configured to receive and compress a first carbon dioxide-containing exhaust stream from an anode of a fuel cell, and a first direct contact absorption cooling tower configured to absorb carbon dioxide from the compressed first exhaust stream and lower a temperature of the compressed first exhaust stream using a first solvent stream containing a physical solvent, to generate a second exhaust stream. The second absorption stage includes: a second compressor configured to receive and compress the second exhaust stream from the first absorption stage, and a second direct contact absorption cooling tower configured to absorb carbon dioxide from the compressed second exhaust stream and lower a temperature of the compressed second exhaust stream using a second solvent stream containing a physical solvent.

In a crude oil purification process including phase separators, a vapor recovery unit (VRU), and dew pointing/dehydration and CO.sub.2 removal membranes, instead of compressing the low boiling point (i.e., C.sub.1-5) hydrocarbon vapor stream from the VRU along with the main portion of gas from the separation train and feeding it to the membranes, it is compressed and dehydrated along with the H.sub.2O/C.sub.3+ hydrocarbon enriched permeate from the dew pointing and dehydration membranes.

Disclosed in certain embodiments are processes for heavy hydrocarbon removal that implement a regeneration loop that introduces an absorbent into a regeneration gas stream, and systems for implementing the same.

A water-lean carbon dioxide absorbent according to the present invention comprises a cyclodiamine and a polyalkylene glycol alkyl ether and further comprises an alkanolamine, wherein the absorbent shows an excellent reaction rate with carbon dioxide, is resistant to degradation due to oxygen and heat, and can greatly reduce energy consumption due to latent heat of water when regenerated, and thus leads to a water-lean carbon dioxide absorbent with improved regeneration efficiency.