Adsorption of ethanol on activated carbon fiber - Simulation and experimental investigations

The performance of low temperature waste heat driven adsorption cooling systems depends on the thermophysical properties of the adsorbent/refrigerant pair as well as the performance of the adsorb/desorber heat exchanger. For the optimum design of the adsorber, it is essential to clarify the local heat and mass transfer phenomena during the adsorption process. This study deals with the adsorption characteristics of activated carbon fiber (ACF) of type A-20 and ethanol pair. Adsorption equilibrium has been measured and Dubinin-Radushkevich (D-R) equation is used to fit the experimental data. The study also presents a one-dimensional transient numerical simulation to investigate the performance of adsorber such as cooling capacity and optimum adsorption cycle time. Adsorber bed temperature, evaporator temperature, ACF bed thickness and apparent density control the heat and mass transfer phenomena in the adsorber/desorber bed. It is found that the cooling capacity can be enhanced by optimizing ACF bed thickness. Simulation results also show that the temperatures of adsorber and evaporator do not have significant effects on the optimum adsorption cycle time.