A Fundamental Study of the Performance of a Multiple Effect Solar Still (2nd Report, Experimental Analysis on the Upward Heating Type Still under the Actual Outdoor Insolation)

Two different types of the multiple effect solar still have been designed and constructed. The difference between them exists in the different methods of collecting solar insolation. The first still (7 stages with a 1.05 m² evaporating area) is associated with the fixed and concentrated type reverse flat plate collector, whereas the second still (5 stages with a 0.41 m² evaporating area) is equipped with a heat-pipe collecting system. The results we have observed throughout the outdoor experiments show that the possible maximum total amount of daily productivity would reach about 14 kg/(m²d) for the multiple effect solar still, and we can expect an improved distillation performance over the ordinary single effect solar still by three times, while another type of multiple effect still may improve by about two times.