Methods for the prevention or mitigation of fouling in amine-treating systems comprising providing circulating aqueous amine solution and a hydrocarbon stream comprising at least one acid gas; and interacting the circulating aqueous amine solution with the hydrocarbon stream comprising the at least one acid gas to remove the acid gas from the hydrocarbon stream and entrain the acid gas into the aqueous amine solution. The circulating aqueous amine solution comprises entrained acid gas comprises foulant precursors; and polysulfide ions are introduced to react with the foulant precursors to decrease the rate of fouling within the circulating aqueous amine solution.

The present disclosure includes systems and methods that integrate a flare gas recovery process with a gas sweetening process used in oil and gas refining. A flare gas recovery system includes a primary gas sweetening unit and a liquid-driven ejector in continuous fluid communication with the primary gas sweetening unit. The ejector includes an inlet configured to receive a motive fluid including a regenerable amine solvent in a lean state from the primary gas sweetening unit, a gas inlet configured to receive a suction fluid including a gas, and a fluid outlet configured to either directly or indirectly discharge to the primary gas sweetening unit a two-phase fluid including a mixture of the suction fluid and the amine solvent in a rich state.

Sulfur-containing compounds are removed from crude CO.sub.2 by conversion to elemental sulfur in a Claus process and subsequently by hydrogenation of the Claus tail gas to convert residual sulfur-containing compounds into H.sub.2S which, after cooling to knock out water and then compressing, is removed, together with any other sulfur-containing impurities, either by physical separation or by chemical reaction with a solid metal oxide to form solid metal sulfide with subsequent oxidative regeneration to produce purified CO.sub.2 and a recycle gas comprising at least one sulfur-containing compound which is recycled to the Claus process. Some H.sub.2S in the Claus tail gas may be removed initially by selective and/or non-selective amine absorption(s) in a tail gas treatment unit prior to removal of residual H.sub.2S and any other residual sulfur-containing impurities by the physical separation or the chemical reaction steps.

An acid gas absorbing mixture and a process for the removal of acid gases from gaseous mixtures containing them, such as natural gas, air and flue gases and an absorbent mixture usable for the removal of acid gases from gaseous mixtures containing them includes at least one diol of general formula R(OH).sub.2 having a normal boiling point equal to or greater than 100 C.; at least one organic base having a pK.sub.b (in water) lower than or equal to 3; and a polar aprotic solvent having a dielectric constant F at 25 C. greater than or equal to 30, a viscosity p at 25 C. lower than or equal to 40 cP (centipoise). The organic base/diol weight ratio is lower than or equal to 0.6, and the aprotic solvent/diol weight ratio is between 0.05 and 0.6.

The invention relates to a method for purifying a gaseous, liquid or aerosol composition, containing at least one pollutant consisting of a volatile inorganic compound (VIC), a siloxane and/or a functional volatile organic compound (Pollution Trap Concept or P.T.C. System).

An acid gas removal apparatus includes a reclaimer control device that performs: first supply water control in which at least one of reflux water, steam condensate, and desalinated water is supplied to a reclaimer as first supply water, at non-volatile component removal reclaiming; second supply water control in which at least one of the reflux water, the steam condensate, and the desalinated water is supplied to the reclaimer, and a washing liquid including an acid gas absorbing liquid is supplied to the reclaimer as second supply water, at an initial stage of finish reclaiming; and third supply water control in which supply of the second supply water is stopped and at least one of the reflux water, the steam condensate, and the desalinated water is supplied as the first supply water, at a later stage of the finish reclaiming.

Processes and systems for oxygen-enhanced Claus carbon dioxide recovery are disclosed. Oxygen is fed to a sulfur recovery unit instead of air. The tail gas is fed to a tail gas treatment unit which produces a treated tail gas, and the treated tail gas is processed in a carbon dioxide recovery unit to produce a carbon dioxide product. A method for retrofitting an existing sulfur recovery unit and tail gas treatment unit so as to recover the carbon dioxide product is also disclosed.

An absorbent liquid which absorbs at least one of CO.sub.2 and H.sub.2S from a gas, including a secondary linear monoamine; a tertiary linear monoamine or a sterically hindered primary monoamine; and a secondary cyclic diamine, wherein a concentration of each of the secondary linear monoamine, the tertiary linear monoamine or the sterically hindered primary monoamine; and the secondary cyclic diamine is less than 30% by weight.

An acid gas removal apparatus includes a reclaimer control device that performs: first supply water control in which at least one of reflux water, steam condensate, and desalinated water is supplied to a reclaimer as first supply water, at non-volatile component removal reclaiming; second supply water control in which at least one of the reflux water, the steam condensate, and the desalinated water is supplied to the reclaimer, and a washing liquid including an acid gas absorbing liquid is supplied to the reclaimer as second supply water, at an initial stage of finish reclaiming; and third supply water control in which supply of the second supply water is stopped and at least one of the reflux water, the steam condensate, and the desalinated water is supplied as the first supply water, at a later stage of the finish reclaiming

The invention relates to the field of membrane gas separation. A method of removing components of gas mixtures which is based on passing the components of a gas mixture through a nanoporous membrane and subsequently selectively absorbing them with a liquid absorbent that is in contact with the nanoporous membrane, wherein to prevent the gas from getting into the liquid phase of the absorbent and the liquid phase of the absorbent from getting into the gas phase, a nanoporous membrane with homogeneous porosity (size distribution less than 50%) and a pore diameter in the range of 5-500 nm is used, and the pressure differential between the gas phase and the liquid absorbent is kept below the membrane bubble point pressure. An acid gas removal performance of more than 0.3 nm.sup.3/(m.sup.2 hour) in terms of CO.sub.2 is achieved at a hollow-fiber membrane packing density of up to 3200 m.sup.2/m.sup.3, which corresponds to a specific volumetric performance of acid gas removal of up to 1000 nm.sup.3 (m.sup.3 hour). The technical result is that of providing effective extraction of undesirable components from natural and process gas mixtures.