Effect of the Tower Type on the Gas Sweetening Process

Abstract

The removal of acid gases, CO₂ and H₂S from natural gas streams is essential for environmental and health reasons. In this work, the simulated gas sweetening unit with Methyl-DiEthanolAmine (MDEA) solvent was studied to improve quality. Firstly, the effect of trays types and then, the effect of various packing and the effect of the packing size were considered on the flow rate of CO₂ and H₂S in the main streams. Results show that with considering the different trays types in the regenerator tower, the flow rate of CO₂ in the sweet gas stream with bubble cap tray is lower than other trays types. Also, with considering the different trays types in the absorber tower, the flow rate of CO₂ in the sweet gas stream with bubble cap tray is lower than other trays types in the absorber tower. In considering with different types of packing, results show that the flow rate of CO₂ with ballast ring packing and the flow rate of H₂S with Raschig ring packing are lower than other types of packing. However, in some types such as cascade miniring, Intalox Saddles and pall ring, there is no difference for the flow rate of CO₂ or H₂S. In all cases, with increasing the size of the packing, the flow rate of CO₂ and H₂S in the sweet gas stream increases, however, this increasing in the metal packing is very small.