WSEAS Transactions on Heat and Mass Transfer
Print ISSN: 1790-5044, E-ISSN: 2224-3461
Volume 7, 2012
Performance of Desiccant wheel for Low Humidity Drying System
Authors: , , , , , ,
Abstract: Drying is an important process for preserving food and non-food products. Solar desiccant drying system has been designed and fabricated for the production of dried products. The system has controllable drying temperature, humidity and flow rate of commercial/industrial capacity in accordance with the characteristics of the material, so that it is not damaged in the drying process. This system consists of heat pipe evacuated tube, cross flow heat exchanger, desiccant wheel, hot water pump, the hot water tank, drying chamber and electrical air heater. Experiments were conducted with two modes: (1) Heat exchanger to heat the air in the regeneration process and (2) Heat exchanger to heat the air after the dehumidification process, while the regeneration process utilized an electrical air heater. Experiment on the desiccant wheel of mode (1) showed that the average effectiveness of sensible dehumidification, sensible regeneration, latent dehumidification and latent regeneration were 72.61%, 82.13%, 79.32% and 78.91% respectively. In mode (2), the average effectiveness of sensible dehumidification, sensible regeneration, latent dehumidification and latent regeneration were 71.4%, 71.99%, 66.97% and 72.8% respectively. Mode (1) was better than mode (2) with mean drying air temperature and absolute humidity were 58oC and 0.0167 kg(H2O)/kg(dry air) respectively. The system was able to evaporate 10.8 kg(H2O)/hr of water in the materials at drying efficiency of 60%.