Absorption is a thermal separation operation in which a selective liquid (scrubbing liquid, absorbing agent) absorbs a component (absorbed substance) of a gas mixture.
The objectives of absorption are:-
In addition, however, absorption also finds application in the extraction of a commercial product (e.g. absorption of NH3 in water , production of hydrochloric acid and nitric acid etc). Depending on the nature of the absorption process, a distinction is made between scrubbing liquids which have a physical and chemical action. In many cases absorption plants mean high investment costs. It is all the more critical that such plats have a long service life, low maintenance and service costs and as great a flexibility as possible in relation to changing applications.