Selexol

Plant conditions used:

Both solvent and the feed gas are normally refrigerated, to improve absorption potential of the solvent. Selexol solvent was chilled down to 4 degC and feed gas chilled to 10 degC. Operating pressure of the Absorber was 33 bar-g, and operating temperature of the Selexol reboiler/regenerator was 151 degC @ 1.5 bar-g.

Differential pressure across the Selexol absorber depends on the number of stages (= number of trays or height of packing) required to achieve product gas specification. and design/actual gas and liquid loadings in the column. Selexol towers are known as quite tall towers, but you will rarely see deltaP across the tower exceeding 0.2 - 0.3 bar under normal circumstances.

2,000mm diameter Selexol absorber handling flow of 1,185 kgmole/hr of solvent with average Mol Weight of 175 (mixture of Selexol and water).