Experiments on waste hot water fed still operating with stirring turbulence

Abstract

ABSTRACT The present work experimentally analyzes the performance of a novel waste hot water fed (WHWF) still for potable water production. In contrast to conventional solar stills, in this still hot water flows over the basin and the mass flow rate of water has been utilized to rotate four small alphabet S-shaped rotors provided at the basin. This rotation induces the stirring turbulence in hot water to enhance the evaporation rate. The non-dependency on solar energy provides the characteristic of continuous (both day and night) water production in all weathers. The variation in thermo-exergic and economic parameters has been studied for varying room temperature in the range of 22–30°C and mass flow rate of hot water in range 150–50 kg/h. The cumulative yield at 22°C is 8–21% and at water mass flow rate of 50 kg/h it is about 7–13% more in comparison of other considered room temperature and mass flow rate values. The improvement in exergy efficiency up to 45.7% is observed in the study. The average cost of potable water is Rs 0.92 (0.012 $) and average payback period is 0.9 year for the WHWF still.