Industrial excess heat driven post-combustion CCS: The effect of stripper temperature level

摘要

The implementation of post-combustion CCS provides an opportunity for the oil refining sector to drastically decrease its CO2 emissions. Previous studies have shown that the largest cost is the heat supply to the stripper reboiler. When performing CCS at an oil refinery it could therefore prove economically beneficial to utilize the excess heat from refinery processes to meet this demand for heat. The present study investigates the heat demand in a stripper reboiler at different temperature levels from 120 degrees C down to 90 degrees C. At temperatures lower than 120 degrees C the heat demand increases, but the availability of excess heat also increases. A case study that connects heat demand results with data from an oil refinery shows that if only excess heat is utilized as a heat source, the amount of CO2 that can be separated is largest when the temperature in the stripper reboiler is 90 degrees C. If, however, CCS with a capture rate of 85% were applied to the four largest chimneys at the refinery, the external heat demand would be the lowest for the standard temperature of 120 degrees C