Investigation of humidification-dehumidification desalination system through waste heat recovery from household air conditioning unit

The performance of a hybrid humidification-dehumidification (HDH) desalination system operated through the waste heat recovered from vapour compression refrigeration (VCR) based household air-conditioning unit is investigated in the present study. The paper deals with the design and simulations aspects to examine the desalination system's performance for hot and medium climatic conditions considering various ranges of space conditioning temperatures (20 degrees C, 24 degrees C and 28 degrees C) respectively. The heat and mass transfer mechanisms in the various components of the system were established using TRNSYS software with experimental validation of the major components of the desalination system. The model operates using the real meteorological data to predict the performance of the hybrid HDH desalination system. Sequence of experiments was conducted and the obtained experimental results were compared with the simulated results. It was found that the average condensate production rate decreased with increase in space conditioning temperature. Further, economic analysis indicated that cost of freshwater produced from the present system is about $0.1658/kg. The obtained results depicted that the developed model could be used to design and predict the behaviour of the desalination system when installed in various meteorological conditions.