US 12,274,975 B2
Two-stage offgas scrubbing
Stephan Peitz, Oer-Erkenschwick (DE); Guido Stochniol, Haltern am See (DE); Martin Oldemeyer, Haltern am See (DE); and Matthias Böse, Raesfeld (DE)
Assigned to Evonik Oxeno GmbH & Co. KG, Marl (DE)
Filed by Evonik Oxeno GmbH & Co. KG, Marl (DE)
Filed on Dec. 22, 2021, as Appl. No. 17/560,226.
Claims priority of application No. 21151735 (EP), filed on Jan. 15, 2021.
Prior Publication US 2022/0226768 A1, Jul. 21, 2022
Int. Cl. B01D 53/02 (2006.01); B01D 53/14 (2006.01); C07C 51/12 (2006.01); C07C 51/44 (2006.01)
CPC B01D 53/1406 (2013.01) [B01D 53/1412 (2013.01); B01D 53/1425 (2013.01); B01D 53/1493 (2013.01); C07C 51/12 (2013.01); C07C 51/44 (2013.01); B01D 2252/2021 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A process for removing organic constituents from a gas stream in a two-stage scrubbing operation, wherein
the gas stream is scrubbed in a first scrubbing unit with a liquid alcoholic scrubbing medium, causing the organic constituents in the gas stream being scrubbed to pass over at least partially into the scrubbing medium, and producing a gas stream with a reduced content of organic constituents, which contains some of the alcoholic scrubbing medium as alcoholic constituents, and an alcoholic scrubbing medium laden with organic constituents; and
the gas stream with a reduced content of organic constituents is scrubbed in a second scrubbing unit with an aqueous scrubbing medium, causing the alcoholic constituents to pass over at least partially into the scrubbing medium and producing a gas stream with a reduced content of organic and alcoholic constituents and an aqueous scrubbing medium laden with alcoholic constituents;
wherein in both scrubbing units at least 0.7 kg of scrubbing medium is used per m3 of gas stream being scrubbed and at least 4 kg of scrubbing medium are used per kg of organic constituents to be removed, and in that
the alcoholic scrubbing medium laden with organic constituents is sent to a reaction in which the alcohol is used as a reactant, and the aqueous scrubbing medium laden with alcoholic constituents is sent into a process in which the water is used as a feedstock or extractant.