A hybrid post-combustion carbon dioxide capture system for capturing carbon dioxide from a flue gas includes a compressor adapted to produce a compressed flue gas stream, a membrane-based carbon dioxide separation unit configured to receive a first portion of the compressed flue gas stream from the compressor, and an aqueous-based carbon dioxide capture unit configured to receive a second portion of the compressed flue gas stream from the compressor whereby the compressed flue gas stream is processed in parallel by the membrane-based carbon dioxide separation unit and the aqueous-based carbon dioxide capture unit.

The use of the combination of (a) an amino compound and (b) a compound including a soft electrophilic centre to scavenge and retain acidic sulfide species at a higher temperature and/or scavenge acidic sulfide species at an increased rate compared to that achieved using the amino compound alone.

A method of scavenging acid sulfide species from an industrial or environmental material, the method comprising contacting the material with: (a) propenal and/or maleimide and/or ethyl-2-chloroacetoacetate; and (b) a base.

The embodiments provide an acidic gas absorbent kept from deterioration, an acidic gas removal method using the absorbent, and an acidic gas removal apparatus using the same. The acidic gas absorbent contains an amine compound and water, and further contains superfine bubble containing inert gas wherein an average diameter of said superfine bubble is 150 nm or less. The acidic gas removal method provided here employs that absorbent. The acidic gas removal apparatus is equipped with a unit for introducing the superfine bubbles into the absorbent.

The present invention is related to a method for determination of unit operations of a chemical plant for acid gas removal, the method carried out by a computer or a distributed computer system and the method comprising the steps of: providing (S1) a first set of parameters for the unit operations; providing (S2) a second set of parameters for the unit operations based on the provided first set of parameters and based on data retrieved from a database; determining (S3) a digital model of the chemical plant based on the first set of parameters and the second set of parameters, wherein the digital model comprises a system of equations defining the unit operations of the chemical plant; selecting (S4) starting points for an equation-based solution method of the system of equations, wherein the starting points are at least partially selected from the: —i) the first set of parameters; —ii) the second set of parameters; and —iii) the data retrieved from the database; determining (S5) resultant settings for the unit operations of the chemical plant using the equation-based solution method for the system of equations initialized by the selected starting points.

A process for producing a deacidified fluid stream from a fluid stream comprising methanol and at least one acid gas, comprising a) an absorption step in which the fluid stream is contacted with an absorbent in an absorber to obtain an absorbent laden with methanol and acid gases and an least partly deacidified fluid stream; b) a regeneration step in which at least a portion of the laden absorbent obtained from step a) is regenerated in a regenerator to obtain an at least partly regenerated absorbent and a gaseous stream comprising methanol and at least one acid gas; c) a recycling step in which at least a substream of the regenerated absorbent from step b) is recycled into the absorption step a); d) a condensation step in which a condensate comprising methanol is condensed out of the gaseous stream from step b);
wherein the regenerator additionally comprises a rescrubbing section, and the condensate from step d) is recycled into the regenerator partly in the upper region of the rescrubbing zone or above the rescrubbing zone.

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 a purification unit (12) and at least one regeneration unit (40) wherein make-up water (72) is added to the regenerated lean hybrid solvent (55) prior to reuse in the first purification unit and no water is recycled into the regeneration unit.

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 62 from the regeneration unit is recycled back into the purification unit and none of the condensed water is reintroduced into the regeneration unit.

The invention relates to an absorbent solution and to a method using this solution for removing acid compounds contained in a gaseous effluent, comprising water and at least one diamine with general formula (I) as follows: ##STR00001## wherein: radicals R.sub.1, R.sub.2, R.sub.3 are each selected indiscriminately among a methyl radical and a hydroxyethyl radical, and at least one radical among R.sub.1, R.sub.2, R.sub.3 is a methyl radical.

In a process for removing CO.sub.2 from a fluid stream by means of an aqueous absorption medium, a) the fluid stream is introduced into a first absorption zone and treated with partially regenerated absorption medium, b) the treated fluid stream is treated with regenerated absorption medium in a second absorption zone, giving a fluid stream which has been freed of CO.sub.2 and a loaded absorption medium, c) the loaded absorption medium is depressurized in a first flash vessel to a pressure of from 1.2 to 3 bar absolute, giving a sub-partially regenerated absorption medium and a first CO.sub.2-comprising gas stream, d) the sub-partially regenerated absorption medium is depressurized in a second flash vessel to a pressure of from 1 to 1.2 bar absolute, giving a partially regenerated absorption medium and a water vapor-comprising, second CO.sub.2-comprising gas stream, e) a substream of the partially regenerated absorption medium is fed into the first absorption zone and a further substream of the partially regenerated absorption medium is fed into a stripper in which the partially regenerated absorption medium is thermally regenerated, with regenerated absorption medium and a third CO.sub.2-comprising gas stream being obtained and the stripper being operated at a pressure which is at least 0.9 bar higher than the pressure in the first flash vessel, f) the regenerated absorption medium is recirculated to the second absorption zone, g) the water vapor-comprising, second CO.sub.2-comprising gas stream is compressed by means of a jet pump and brought into direct heat exchange contact with the loaded absorption medium in the first flash vessel, with the jet pump being operated by means of the third CO.sub.2-comprising gas stream. The latent heat of the water vapor-comprising gas streams remains in the process and the use of a costly compressor is dispensable.