(481a) Integration of Post-Combustion Capture with Compression and Liquefaction Process of CO2

Along with the worldwide efforts to reduce the greenhouse gases, Carbon Capture and Storage/Sequestration (CCS) has emerged as one of the most promising technologies in South Korea. Capture process is known to occupy 70 to 80 percent of the overall energy demands in CCS technology, and consequently, most of up-to-date research has been dedicated to this aspect by developing innovative CO₂ absorbents or modifying the process itself to reduce the regeneration energy of the absorbent. Each constituent of the technology can then be integrated with one another in order to mitigate the overall energy consumption. However, there is no possible candidate for CO₂ storage site in Korea at this time, so the capture process must be integrated with an intermediate compression process instead which is always required to transport CO₂from capture plant to the storage site.

In this study, a process simulation including both post-combustion capture of CO₂ using MEA absorbent and multi-stage compression was performed using Aspen Plus®. Different physical property methods were selected for each process to allow more stable and accurate simulation. [1] It was assumed that the compressed (liquefied) CO₂ will be transported via CO₂ carrier, which requires appropriate specifications of CO₂ for ship loading. [2] In addition, 4-stage compression system with intercooling was adopted where both cold and hot utilities are available from compression as well as isenthalpic expansion. A quantitative analysis of how these utilities can be used was carried out so that the energy required for capture as well as the overall process was reduced.

This research was supported by a grant from the LNG Plant R&D Center funded by the Ministry of Land, Transportation and Maritime Affairs (MLTM) of the Korean government.

References:

[1] Van Wagener, D.H., Rochelle, G.T., 2011. Stripper configurations for CO₂capture by aqueous monoethanolamine, Chem. Eng. Res. Des. 89, 1639-1646.

[2] Aspelund A., Jordal, K., 2007. Gas Conditioning–The interface between CO₂ capture and transport, Int. J. Greenhouse Gas Control, 1(3), 343-354.