Improving Energy Efficiency of Carbon Capture Processes with Heat Pumps

Carbon capture based on chemical absorption in amine-based solvents is the most relevant technology option to reduce CO2 emissions from hard-to-abate industrial CO2 sources and power plants. Because of the energy consumption of the carbon capture process, which is mainly attributed to heating the desorber, carbon capture has a negative impact on the efficiency of the process where CO2 is removed. Heat pumps allow for heat recovery and provide high temperature process heat. Due to recent developments, heat pumps are now capable of supplying steam and providing high temperatures enabling new applications. This contribution investigates the integration of heat pumps into the carbon capture process of a furnace for steel processing to determine the most suitable heat sources and sinks and the achievable energy savings. The energy consumption of the carbon capture process can be lowered by 50% due to the integration of steam generating heat pumps. The cost analysis shows that the costs of steam have the highest influence on the costs of captured CO2.