Process Modifications for Solvent-Based Post Combustion CO2 Capture

Amine based CO2 scrubbing processes have been patented since 1930 but very few process improvements have been reported prior to the oil crisis of 1975-1980, which led to the requirement for more energy efficient processes. Nevertheless most of these patents are solvent oriented. With CO2 capture technology development, a sharp increase of process improvement patents and scientific articles can be witnessed since 2004 in parallel with the development of new solvents. In this work, a thorough review of patent database and open literature has been carried out in order to be as exhaustive as possible. The individual process modifications and patents are analyzed and then generalised into "elementary" modification groups. These elementary modifications are then sorted into main categories related to their effect on the process. In total, 20 elementary modifications have been sorted into three main categories: absorption enhancement (increasing rich loading or reducing absorption driving force difference along column height), thermal integration (minimizing the rejected heat of process and excessive thermal driving force) and heat pump effect (increasing heat quality with electricity). Figure 1 summarizes these modifications and shows an illustrative flow scheme for each of them. In the final paper, their mean of action will be described and discussed in relation to their induced complexity, flexibility, cost and expected performances. (C) 2014 The Authors. Published by Elsevier Ltd.