Abstract
We present a steady-state, optimization-based techno-economic study of a continuous fluidized temperature-swing adsorption (TSA) system for post-combustion CO2 capture from biomass-derived flue gas, using two adsorption stages and one desorption stage with integrated heat-pump thermal management. The GAMS/CONOPT4 model couples molar and energy balances, Toth adsorption equilibrium, fluidized-bed hydrodynamics and literature cost correlations. Optimization yields CO2 purity of 96% v/v and 95.5% recovery at low, safe pressures with particle Reynolds numbers of 2-11, indicating near-minimum-fluidization operation. The nominal capture cost is 87 USD/tonCO2 with an internal rate of return of 42%; utilities comprise 49% of annualized costs and the adsorption compressor dominates equipment capital. Disabling the heat pump increases modeled capture cost to 124 USD/tonCO2, highlighting the heat pump's decisive role in reducing energy demand and costs. Adding adsorption stages lowers modeled cost further but produces impractically shallow beds, revealing a trade-off between mass-transfer performance and feasible bed geometry. A sensitivity analysis demonstrated a linear positive correlation between electricity cost and capture cost, with capture costs potentially as low as 50 USD/tonCO2 and an internal rate of return as high as 64%. While results demonstrate the technical and economic plausibility of a heat-pump-assisted fluidized TSA under the stated assumptions, the study recommends including flue contaminants, refined heat-exchanger and pressure-drop models, and experimental validation for scale-up.