Abstract

Human activities have caused a continuous increase in global temperatures due to high global
greenhouse gas emissions, especially CO2. The Intergovernmental Panel on Climate Change stated
that to reduce these emissions carbon capture and utilization (CCU) must be implemented, despite
its energy-intensive nature. In this project, various innovative approaches have been developed to
improve the performance of solvent based absorption systems and their integration with CCU. The
reduction in energy is achieved by hydrogen injection into the CO2 removal separators to act as a
stripping agent. Nine configurations (4 physical, 5 chemical) are simulated and analyzed.
Furthermore, the proposed approaches are tested for two scenarios: 1) CO2 capture from the flue
gas of a cement plant. 2) revamping the CO2 capture unit of the synthesis gas stream of an existing
ammonia plant. The results for physical absorption revealed that around 48%-77% reduction in
the net energy consumption for flue gas and syngas are achievable respectively compared to the
base case capture process and the traditional processes available in the market. As a result, the
capture cost has decreased by 10%-25%, for flue gas and syngas respectively ($80.92/$29.43 from
$89.34/$39 per tonne CO2). In the chemical case, the proposed concept is integrated with the use
of high-temperature heat pump. According to our results, a 13% improvement for flue gas and 5%
for syngas in the coefficient of performance of the heat pump is achievable. The results of this
project can be used to improve the overall performance of the CCU technologies and to be
compared with other emerging technologies.