Model verification and evaluation of the rich-split process modification at an Australian-based post combustion CO2 capture pilot plant



The CSIRO is involved in three CO2 capture pilot plants operating at different coal-fired power stations throughout Australia. The most recently completed of these is the Tarong CO2 capture pilot plant located at Tarong power station, Nanango, Queensland. The first phase of the experimental program with this pilot plant included operation with monoethanolamine (MEA). This involved parametric studies, process modifications, and finally implementation of 24 h operation. Operation of the pilot plant has shown MEA to be effective in capturing CO2 from the flue gas from Tarong Power Station. CO2 capture efficiencies of up to 94%, and regeneration energies as low as 3.6 MJ/kgCO2 have been achieved. The design of the pilot plant was completed using a commercially available process modeling software tool. Results obtained from the pilot plant were then compared to the model predictions including temperature, solvent CO2 loading, and CO2 gas concentration profiles through the absorber column. A good match has been obtained between the modeling and pilot plant data, verifying the software can be used to predict the performance of the pilot plant when operating on MEA. During this project, the rich-split process modification was also evaluated. The results suggest that the rich-split modification can achieve some reduction in reboiler duty and a considerable reduction in the condenser duty. The amount of reduction is dependent on plant design, particularly the efficiency of the lean/rich heat exchanger. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd