Ashleigh Cousins

Process Implications of CO2 Capture Solvent Selection

In the development of energy efficient solvents for advanced CO2 capture processes, it has often been the case that potentially excellent solvents are overlooked or set aside because of perceived process difficulties or extra costs due to the physical, chemical or thermodynamic properties of the solvent. This chapter considers the process implications of solvent selection with the objective of selecting and designing the process to suit the solvent rather than forcing the solvent into an existing process. The chapter discusses the design, modelling and costing of conventional amine processes insofar as advanced energy efficient solvents still rely on this process. Individual solvent properties, including reaction kinetics, thermodynamics and physical properties are outlined and their impact on design are discussed. Aspects such as degradation products, corrosivity and environmental considerations will impact the selection of process equipment and materials of construction. The impact of these properties of energy efficient solvents on individual unit operations are also discussed in some detail.

26 – Pilot plant operation for liquid absorption-based post-combustion CO2 capture

Pilot-scale operation is often used when developing new technologies or processes for commercial application. It allows collation of realistic operating and engineering data at a smaller scale, and hence a smaller cost, than would be achieved at a full-size facility. Liquid absorbent-based removal of CO2 from process gas streams is not a new technology, having been used in applications such as natural gas processing. However, it has only recently been used to treat combustion flue gases. Research and commercial organizations worldwide have now constructed and operated pilot-scale post-combustion CO2 capture facilities operating on both synthetic and real combustion flue gases. This chapter considers the design and operation of these facilities, and also reviews the results achieved at several CO2 capture pilot plants.