Experimental Analysis of Energy Savings in a Combined Rotary Desiccant Dehumidifier with a Purge Section

This study focuses on improving the performance of desiccant dehumidifiers using desiccant rotors, which are widely utilized in various industries, such as manufacturing, food, and construction, to enhance product quality and production efficiency. The combined desiccant dehumidifier can reduce energy consumption compared to traditional standard or purge dehumidifiers. The system operates in normal mode during seasons with high outdoor humidity and in purge mode during seasons with low outdoor humidity. By utilizing dampers, the air passing through the dry desiccant rotor can either be directly discharged indoors or supplied to the regeneration section, allowing the system to operate in two modes within a single unit. The first part of the study involved comparing the performance of the equipment through experiments. The second part compared the results from the dehumidifier rotor performance simulation program to check for deviations and validate its effectiveness. In the first experiment, the energy consumption of the standard desiccant dehumidifier in normal mode was compared with that of the combined desiccant dehumidifier in normal mode. In the second experiment, the energy consumption of the standard desiccant dehumidifier in normal mode was compared with that of the combined desiccant dehumidifier in purge mode. The airflow, temperature, and humidity values used in each experiment were analyzed using a dehumidification performance simulation program, and the deviation was found to be within 10%. Therefore, the performance analysis via simulation was considered valid. The dehumidification performance of the combined desiccant dehumidifier was found to be 5% more efficient than the traditional standard desiccant dehumidifier and 9.5% more efficient than the purge dehumidifier. Furthermore, energy consumption simulations were conducted for representative regions in Korea. The results showed energy reductions of 65% in Seoul, 65% in Daejeon, and 67% in Busan. The findings of this study suggest that energy savings can be achieved by appropriately adjusting the operation mode between normal and purge modes based on outdoor conditions.