Development of a preliminary cost estimation model for the design of K2CO3-based CO2 capture plants

Climate change has become an increasingly relevant issue in recent years, prompting industries to pay growing attention to the reduction of CO2 emissions for regulatory, economic, and reputational reasons. In several industrial sectors; however, direct modifications to the production process are not always feasible or economic; this is the case, for instance, of the glass manufacturing industry, where the delicate glass manufacturing process, unchanged for years, makes post-combustion CO2 capture a superior technology compared to fuel switching (to hydrogen, electricity, etc.), which would entail significant modifications to the furnace and, consequently, to the traditional glass production process. Within this framework, the present work was developed in collaboration with K2-CO2, a start-up company focused on the design of turnkey integrated CO2 capture plants, including upstream flue gas pretreatment and downstream liquefaction unit. Flue gas pretreatment is aimed at cleaning and cooling the flue gas, thereby making it suitable for feeding the carbon capture plant; the liquefaction unit is aimed at purifying the captured CO2, thus making it suitable for carbon capture and storage (CCS) or utilization (CCU). The carbon capture technology uses an aqueous K2CO3 solution, whose process licensor is Giammarco Technologies. The objective of this thesis is the development of a mathematical model, implemented in Microsoft Excel, for a rapid and reliable estimation of the costs associated with the design and construction of CO2 capture plants based on absorption using K2CO3. Starting from the characterization of the flue gas and from the desired target CO2 capture efficiency, the model allows the estimation of the main CAPEX and OPEX components through the sizing of the main process units and the application of economic scaling correlations from historic data of old projects. This approach enables the provision of preliminary cost estimates within short timeframes, without the need to involve external third parties, allowing the client to assess the feasibility of a subsequent detailed feasibility study. The work presents the analysis of the K2CO3 absorption process, the description of the main equipment items, the data processing methodology, the structure of the developed model, and its retrospective application to a reference project. The results demonstrate the capability of the model to provide plausible cost estimates and to significantly reduce economic evaluation times during the early stages of process design, although further validation against detailed project data is still required. Within this framework, the present work was developed in collaboration with K2-CO2, a start-up company specialized in the design of CO2 capture plants. The objective of this thesis is the development of a mathematical model, implemented in a Microsoft Excel spreadsheet, for the rapid and reliable estimation of the costs associated with the design and construction of CO2 capture plants based on absorption using K2CO3. Starting from flue gas data provided by the client and from the target CO2 capture efficiency, the model allows the estimation of the overall plant cost through the sizing of the main process units and the application of economic scaling correlations. This approach enables the provision of preliminary cost quotations within short timeframes, without the need to involve external third parties. The work presents the analysis of the K2CO3 absorption process, the description of the main equipment items, the data processing methodology, the structure of the developed model, and its validation through real industrial case studies. The results demonstrate the capability of the model to provide consistent cost estimates and to significantly reduce economic evaluation times during the early stages of process design.