Performance analysis on a solar bubble column humidification dehumidification desalination system

This paper describes the performance of a solar bubble column humidification dehumidification desalination system. A solar bubble column humidifier is fabricated similar to a single slope single basin solar still, where the saline water directly gets heated by the solar energy. The air enters into the humidifier through the nozzles, mixes with the water, gets humidified, and part of the air is condensed in the glass cover and the remaining air is condensed in the dehumidifier. Preliminary experiments are carried out to study the ability of the bubble column humidifier and then the humidifier connected with a dehumidifier to analyze the overall system performance. First set of experiments are carried out to analyze the effect of direct and preheated air supply (by a solar air heater) in the humidifier. Integration of solar air heater shows considerable enhancement of specific humidity in the humidifier outlet. In second set of experiments, the humidifier is integrated with the solar air heater and studied by varying the humidifier water depth and mass flow rate of air. The experiments are continued to investigate the humidifier performance with the turbulators in solar air heater. The best humidifier water depth, air flow rate and turbulator are selected from the previous experiments and the test is continued by integrating the humidifier with the dehumidifier. The humidifier integrated with the solar air heater contains concave turbulators provide the maximum specific humidity gain of 0.187 kgwater/kgair, whereas the humidifier integrated with the solar air heater without turbulator gives the maximum specific humidity gain of about 0.11 kgwater/kgair. The peak distillate of 20.61 kg/m2 day is collected.