The physical absorption of CO2 in water containing different types of particles was studied in a micro-channel operated under Taylor flow. The maximum enhancement factors of 1.43-2.15 were measured for activated carb...The physical absorption of CO2 in water containing different types of particles was studied in a micro-channel operated under Taylor flow. The maximum enhancement factors of 1.43-2.15 were measured for activated carbon (AcC) particles. The analysis shows that the enhancement effect can be attributed to the shuttle mechanism. Considering the separate contributions of mass transfer from bubble cap and liquid film, a heterogeneous enhance- ment model is developed. According to this model, the enhancement factors Ecap, EFilm and Eov are mainly determined by mass transfer coefficient gL (gL Cap and KL Film), adsorptive capacity of particles m, and coverage fraction of particles at gas-liquid interface (. With both effects of particle-to-interface adhesion and apparent viscosity included, the model nredicts the enhancement effect of AcC varticles reasonably well.展开更多
Based on analysis of energy dissipation in the core region of gas-solid fluidized bed risers, a simplified model for determination of core-annulus solids mass transfer coefficient was developed according to turbulent ...Based on analysis of energy dissipation in the core region of gas-solid fluidized bed risers, a simplified model for determination of core-annulus solids mass transfer coefficient was developed according to turbulent diffusion mechanism of particles. The simulation results are consistent with published experimental data. Core-annulus solids mass transfer coefficient decreases with increasing particle size, particle density and solids circulation rate,but generally increases with increasing superficial gas velocity and riser diameter. In the upper dilute region of gas-solid fluidized bed risers, core-annulus solids mass transfer coefficient was found to change little with the axial coordinate in the bed.展开更多
基金Supported by the National'Natural Science Foundation of China (20706041, 20876109), and the Natural Science Foundation of Tianjin, China (09JCYBJC06500).
文摘The physical absorption of CO2 in water containing different types of particles was studied in a micro-channel operated under Taylor flow. The maximum enhancement factors of 1.43-2.15 were measured for activated carbon (AcC) particles. The analysis shows that the enhancement effect can be attributed to the shuttle mechanism. Considering the separate contributions of mass transfer from bubble cap and liquid film, a heterogeneous enhance- ment model is developed. According to this model, the enhancement factors Ecap, EFilm and Eov are mainly determined by mass transfer coefficient gL (gL Cap and KL Film), adsorptive capacity of particles m, and coverage fraction of particles at gas-liquid interface (. With both effects of particle-to-interface adhesion and apparent viscosity included, the model nredicts the enhancement effect of AcC varticles reasonably well.
文摘Based on analysis of energy dissipation in the core region of gas-solid fluidized bed risers, a simplified model for determination of core-annulus solids mass transfer coefficient was developed according to turbulent diffusion mechanism of particles. The simulation results are consistent with published experimental data. Core-annulus solids mass transfer coefficient decreases with increasing particle size, particle density and solids circulation rate,but generally increases with increasing superficial gas velocity and riser diameter. In the upper dilute region of gas-solid fluidized bed risers, core-annulus solids mass transfer coefficient was found to change little with the axial coordinate in the bed.