Energy & Fuels, Vol.30, No.8, 6570-6577, 2016
Experimental Investigation of Precombustion CO2 Capture Using a Fixed Bed of Coal Particles in the Presence of Tetrahydrofuran
This work presents a hybrid, gas adsorption and hydrate formation process for CO2 capture from fuel gas (40 mol % CO2/H-2) using a fixed bed reactor (FBR) of coal particles. To better understand the CO2 capture performance of this hybrid process, the effects of particle size and tetrahydrofuran (THF) concentration on gas consumption and CO2 selectivity were experimentally investigated at 100% liquid saturation of the fixed bed. The experiments were conducted at 274.2 K with the initial pressure fixed at 3.0 MPa. The results indicated that medium-sized coal particles (0.5-1.0 mm) are more favorable than small (0.1-0.5 mm) and large (1.0-3.0 mm) coal particles as higher gas uptake, CO2 recovery, and separation factor were obtained in the FBR filled with medium-sized coal particles. Gas uptake was observed to increase while increasing THF concentration from 1.0 to 5.6 mol %, but the optimum CO2 selectivity was obtained at 1.0 mol % THF. The gas uptake obtained at 1.0 mol % THF in the FBR of coal particles was comparable with that obtained at 5.53 mol % THE in the FBR of silica sand at the same temperature and pressure conditions. Therefore, the FBR of coal particles saturated by 1.0 mol % THF solution can be used as a viable format for CO2 capture from fuel gas when considering gas uptake and CO2 selectivity at the same time.