Performance Evaluation of Solid Desiccant Wheel Regenerated by Waste Heat or Renewable Energy

Abstract

Abstract To remove moisture, solid desiccant wheel technology presents an energy-efficient alternative to traditional systems especially when solar energy and waste heat come into play. Solid desiccant wheels can be coupled with other systems to provide desired air quality. In order to solve the problem of high energy consumption for regeneration of desiccant wheels, systems involving desiccant wheels use solar thermal energy or waste heat to regenerate desiccant material so dehumidification process is done by this technology while required energy to dehumidify air is provided by waste heat or renewable energy. The main component in these systems is desiccant wheel which should operate efficiently. In this study, performance of solid desiccant wheel is evaluated and affecting factors consisting of air humidity ratio, regeneration process and air process temperatures, mass flow rates, and wheel revolution are investigated. Software provided by Novel Aire Company is used to calculate outlet air conditions. Using the software, the performance of a rotary dehumidifier is studied based on effectiveness parameters including moisture removal capacity (MRC), sensible coefficient of performance (COPSen), latent coefficient of performance (COPLat) and total coefficient of performance (COP Total). In addition, affecting factors change as described: inlet air temperature between 15 °C to 40 °C, regeneration temperature between 65 °C to 110 °C, humidity ratio between 10 to 20 g/kg, air flow rates between 0.72 Kg/s to 1.28 m/s, and rotational speed of wheel between 10 to 40 RPH.