Performance evaluation of various fiber paper matrix desiccant wheels coated with nano-adsorbent for energy efficient dehumidification

This paper investigates the dehumidification performance of desiccant wheel (DW) with different fiber paper (FP) substrates such as wood pulp, glass fiber, ceramic fiber, Nomex fiber, and brown wood pulp FP, coated with nano SiO2 as adsorbent for energy efficient air dehumidification. The FP substrates are coated with SiO2 nano-adsorbent by impregnation-dip coating method to the thickness of 5 mils. The adsorption capacity for all the FP substrates was evaluated at temperature of 28 degrees C and 70% relative humidity. It was found that the adsorption capacity increases with increasing the desiccant coatings. The adsorption capacity of GFP was high with a value of 57.6 g center dot m(-2) and thermal conductivity was improved from 0.038 W center dot m(-1)center dot K-1 to 0.094 W center dot m(-1)center dot K-1 with desorption temperature of 45 degrees C after coating with SiO2 nano-adsorbent. Among varying regeneration temperature from 50-90 degrees C, the desiccant wheel GFP-SiO2-DW has high dehumidification capacity and dehumidification coefficient of performance (DCOP) of 2.1 g center dot kg(-1) and 2.2 respectively at 50 degrees C. The results confirm that less energy is necessary for the regeneration heater which can be supplied from a low-grade energy source thus reducing the energy consumption for regeneration of the desiccant wheel.