Dynamic modelling of a CO2 capture and purification unit for an oxy-coal-fired power plant

Oxy-combustion is a promising pathway to capture CO2 from coal fired power plants that compete favourably with other CO2 capture technology pathways, such as post-combustion and pre-combustion. Oxy-combustion has attracted attention because it provides a CO2-enriched flue gas stream which can be further purified, if required, using a relatively simple multi-stage compression and cooling processes. Several studies have been published on the capture and purification of CO2 from oxy-combustion. However, knowledge of the dynamic behaviour of the CO2 capture and purification process is very limited. Dynamic insight is key to design suitable control schemes to ensure that this process can be operated at near optimal conditions, while maximizing CO2 recovery and meeting product quality requirements. This study aims to develop and validate a dynamic model of CO2 capture, purification and compression process for integration with oxy-fuel combustion plants. The model was developed and validated based on a study performed by the International Energy Agency Greenhouse Gas (IEAGHG) R&D programme (Dillon et al., 2005). Mathematical models are provided, steady state data are validated and case studies performed to study the transient behaviour of the process in response to process disturbances.