Thermal performance analysis of a low-cost and eco-friendly rotary desiccant wheel dehumidification system with recycled materials

Abstract

Conventional rotary desiccant wheel dehumidification systems often present challenges regarding practicality, cost, size, and usability. This study experimentally investigates the performance of a novel, low-cost (∼$100) dehumidification system featuring a 2 cm thick silica gel desiccant wheel. The system's optimal operating conditions are determined under various regeneration temperatures (40 °C, 50 °C, and 60 °C) and fan speeds (2 m/s and 4 m/s), establishing baseline parameters for traditional rotary desiccant systems. Experimental results demonstrated a maximum dehumidification coefficient of performance of 0.312 at 50 °C regeneration temperature and 2 m/s fan speed, decreasing to 0.254 at 60 °C and 4 m/s. Moisture removal and release rates were quantified across various operating conditions. At a regeneration temperature of 60 °C, moisture removal/release rates were 4.55/1.16 g/kg(d.a.) and 3.97/0.42 g/kg(d.a.) for fan speeds of 2 m/s and 4 m/s, respectively. Corresponding values at 50 °C were 3.48/0.54 g/kg(d.a.) and 2.77/0.28 g/kg(d.a.). Finally, at 40 °C, these rates were 1.53/0.09 g/kg(d.a.) and 0.59/0.05 g/kg(d.a.) for 2 m/s and 4 m/s, respectively. These results indicate optimal operating conditions of 50 °C at 2 m/s and 60 °C at 4 m/s fan speed. Recognising that optimal conditions may vary with ambient humidity, this study provides valuable insights into the relationship between moisture removal and DCOP for each tested scenario. This innovative, cost-effective system demonstrates promising results for rotary desiccant dehumidification and offers the potential for integration with traditional air conditioning systems to enhance energy efficiency.