Comparative Assessment of Carbon Capture Processes from the Perspective of Selection Criteria

The Paris Agreement of 2015 aims to keep the global average temperature increase below 2 °C above pre-industrial levels and to limit warming to 1.5 °C if possible. The European Union has set ambitious targets (-55 % by 2030 and Net-Zero by 2050) to support the European Green Deal (EGD). To reach the goals by the deadlines, extensive pre- and post-source measures are necessary. This article focuses on post-source measures and seeks to identify, quantify, and evaluate the selection criteria of the applicability of carbon capture techniques. The specific energy demand (theoretical minimum work required to separate CO2 from a gaseous mixture) of a capture process can be derived from the first and second laws of thermodynamics. There are, however, other factors that can significantly influence the decision-making process for carbon capture from a given polluting source. The first criterion group is related to the 2nd law efficiency, i.e., the proportionality between theoretical minimum work and real energy demand that can be achieved in practice, while the second group covers the specific separation cost as a primary economic parameter. The research gives comprehensive insights into the different carbon capture methodologies and analyses their dependency on CO2 concentration, the presence of impurities, and operational conditions such as temperature and pressure. Based on the analysis outcomes, selection criteria are proposed to help match mature technologies (TRL 7–9) to specific gas compositions and industrial applications, primarily for process gases from power plants, chemical industries, and cement production, supporting more efficient and context-dependent implementation and the green transition.