A framework for optimisation and techno-economic analysis of CO ₂ pressurisation strategies for pipeline transportation

This paper presents a framework for optimisation and techno-economic analysis of various pressurisation pathways for CO 2 pipeline transportation. The pressurisation pathways include a conventional compression only case from initial to final pressure, a sub-critical compression part followed by cooling, liquefaction and pumping and also a super-critical compression part followed by cooling and dense phase pumping. The presented framework is developed based on open-source components and information available in the public domain. The framework includes a high level of flexibility to study variations in intial and final pressures, inclusion of inter-stage pressure drop, inter-stage cooling temperature, liquefaction/pumping pressure, among others. The implemented methods, i.e., the thermodynamic and economic models applied, are rigorously validated and bench-marked against literature data. Contrary to former studies that focus mainly on reduction of the work required for pressurisation, the presented method includes additional capabilities to assess CAPEX, OPEX and the levelised cost of CO 2 compression. The analysis shows that in some cases the minimum levelised cost does not coincide with the minimum work. It is also demonstrated that for some cases the super-critical compression/cooling/pumping case and the sub-critical compression/cooling/liquefaction/pumping pathways provide optimal levelised cost compared to a multi-stage compression only case.