Technical Feasibility of an Intensified Absorption Process for Bioenergy Carbon Capture and Storage (BECCS)

Abstract: This project aims to evaluate the technical feasibility of an absorption process for carbon capture and storage (CCS). Currently, the CCS process commonly used in the industry is energy and cost-intensive, making its large-scale development a difficult task. The process under evaluation in this project is labeled as an intensified CCS process as it is more energy-efficient, theoretically, compared to the current standard process. The intensified process is based on absorption with aqueous K2CO3/KHCO3 followed by cristallization of KHCO3. The project aims to show the technical feasibility of two parts of the intensified process, the cooling crystallization in the reactor and the regeneration of carbon dioxide through calcination. The cooling crystallization was conducted at different cooling rates for two different solution compositions, while the calcination was conducted the same for all tests. Microscopic images were utilized to examine the relationship between cooling rates, solution composition, crystal size, and clustering. Thermogravimetric analysis was used to simulate the calcination and to analyze the crystals' decomposition and purity. The report concludes that none clustered selective crystallization of potassium bicarbonate and the total regeneration of carbon dioxide through calcination were achieved. A conclusive correlation between cooling rates and crystal yields could not be proven. And the relationship between crystal size and cooling rates substantially deviated from what was expected. Based on the results the intensified process is deemed technically feasible.