(57f) Techno-Economic Analysis of Post-Combustion Carbon Capture with a 3rd Generation Water-Lean Solvent
Aqueous amines offer one of the most competitive, mature and scalable technology platforms for post-combustion carbon capture. However, the high costs associated with both energy penalties and the necessary capital investments limit its economic viability. The significant energy required to regenerate aqueous amines is due to the high water content. The reason is that the water content increased the condenser duty and this, in turn, increases the reboiler duty. Therefore water-lean solvents have the potential to significantly reduce the reboiler duty. CO2-Binding Organic Liquids (CO2BOLs) comprise a class of water-lean solvents being developed at PNNL. These solvents have shown considerable promise towards reducing the carbon capture energy consumption by reducing the solvent water content. The energetic benefits of CO2BOLs can be further realized through advanced process configurations, which have been intensively studied for aqueous amines, but not yet for water-lean solvents. Indeed, due to the physical and thermodynamic property differences between aqueous and water-lean solvents, viable configurations for aqueous amines may not be optimal for water-lean solvents. Further, expensive construction materials, such as stainless steels, which are required to prevent corrosion for many aqueous amines, may not be required for CO2BOLs due to their weaker corrosiveness and unique wetting properties. This opens up the option of replacing stainless steel packing with plastics, which would result in a considerable saving of capital cost. With the above motivations, equivalent work calculations and techno-economic analysis were conducted to quantitatively evaluate different process configurations for post-combustion carbon capture using a 3rd generation CO2BOL. In this presentation, we identify the advantages and limitations of this CO2BOLs solvent, and the opportunities to reduce the cost of carbon capture.