Optimal Design and Techno-Economic Analysis of 3D-Printed, Intensified Packings for Absorbers and Strippers in Solvent-Based CO 2 Capture

A potential technology for the CO2 absorption process is utilizing intensified structured packing with embedded cooling/heating channels for continuous heat exchange, which can overcome limitations of discrete methods, such as discrete intercooling and centralized reboilers, to aid in reducing energy consumption and decreasing costs. This work investigates the modeling of intensified packing (IP) for the stripper tower, extending on previous work for the absorber, which distributes heat internally within the column, improving the thermodynamics for the solvent regeneration process. The model includes submodels for steam turbine extraction to produce steam at various qualities as well as a surrogate model for calculating steam enthalpy. A cost model for a plant-scale absorption capture process was developed, allowing for the design of the plant to be optimized, subject to minimizing capture cost using two different power plant flue gas sources. In this optimization, the placement of IP in both towers is optimized to balance the trade-off between enhanced heat transfer and reduced mass transfer volume. For natural gas combined cycle flue gas, the standard process configuration had a minimum cost of 65. 40/tonne CO2, and considering IP, the minimum capture cost is reduced to 62. 73/tonne, with utilization in the stripper column, which reduces yearly costs by up to 2. 67 MM/yr. Cooling the absorber through IP, or intercoolers, was only found to be beneficial at higher capture rates, with IP in both towers having a cost of capture of 68. 08/tonne at 99. 9% capture, a reduction of 12. 64/tonne when using only intercoolers at the same capture rate. When capturing from pulverized-coal power plants, the minimum cost of capture when using IP in both towers is 44. 18/tonne (at 97% capture), while the standard configuration with and without intercoolers was 45. 69 and 47. 22 per tonne, respectively. This results in a reduction in yearly costs of 16. 98 MM/yr from the base-case configuration. At this higher CO2 concentration, cooling in the absorber from the IP becomes extremely beneficial, reducing energy consumption by up to 6%.