Chemie Ingenieur Technik, Vol.84, No.6, 849-858, 2012
A New Chemical System Solution for Acid Gas Removal
An energy-efficient absorbent formulation for separating acid gases (e.g. CO2, H2S) from gas streams such as natural gas, syngas or flue gas is important for a number of industrial applications. In many cases, a substantial share of their costs is driven by the operational expenditure (OPEX) of the CO2 separation unit. One possible strategy for reducing OPEX is the improvement of the absorbent performance. Although a number of absorbents for the separation of CO2 from gas streams exist, there is still a need to develop CO2 absorbents with an improved absorption performance, less corrosion and foaming, no nitrosamine formation, lower energy requirement and therefore less OPEX. Selected performance results of a new family of amine-based CO2 absorbents are summarized. High cyclic capacities in the range of 2.9 to 3.2?mol?CO2?kg1 absorbent and low absorption enthalpies of about 30?kJ?mol1 allow for significant savings in the regeneration energy of the absorbent. Calculations with the modified Kremser model indicated a reduction in the specific reboiler heat duty of 45?%. Furthermore, the absorbents developed show much lower corrosion rates than state-of-the-art solutions that are currently employed.
Keywords:Absorption;Carbon capture;Chemical industry;Energy efficiency;Operational expenditure;Separation;Sustainability