Performance of multiple effect diffusion stills

Abstract Experimental testing of a three-effect diffusion still is carried out. The experiment is designed to test the effect of the heating fluid temperature input to the still T h and the feed rate of desalinated water to the still F on the performance of the still. The results produced several empirical relations to predict the following in terms of the T h and F : the average temperature of each effect, the rate of distillate produced by each effect, and the performance ratio of the still. In addition, a mathematical simulation is given for the n -effect diffusion still. The mathematical model is verified by comparing its results with the experimental results of the three-effect diffusion still. The model is further used to predict the performance of a ten-effect diffusion still at the following parametric conditions: various values of the dimensionless parameters N 3 and N 4 , various heating medium temperatures input to the still, and various feed rates to the still.