Post-combustion Capture of CO₂: Results from the Solvent Absorption Capture Plant at Hazelwood Power Station Using Potassium Carbonate Solvent

Post-combustion capture of CO2 from flue gas generated in a 1600 MW brown-coal-fired power station has been demonstrated using a solvent absorption process. The plant, located at International Power’s Hazelwood power station in Victoria’s Latrobe Valley, was designed to capture up to 25 tons/day of CO2 (expandable to 50 tons/day of CO2). The design of the capture plant was based on a proprietary solvent (BASF PuraTreat F). The main focus of this work, however, is to describe the performance of the plant using an unpromoted 30 wt % potassium carbonate (K2CO3) solution. The CO2-capture plant was successfully operated using both BASF PuratTreat F and K2CO3, during which performance data were collected and analyzed. Although the plant only absorbed 20–25% of CO2 from the flue gas when using the potassium carbonate solvent, valuable operating data were collected, which enabled process simulations to be compared to real plant data. Aspen Plus software was used to predict the performance of the plant while operating with potassium carbonate. In general, the model shows a slight difference (within ±5%) compared to the pilot-plant results. This benchmarked model is an important part of the ongoing development of novel precipitating potassium carbonate processes for large-scale post-combustion CO2 capture.