Charcoal Particles as an Absorber Medium in Non-Conventional Solar Stills

Abstract

A solar still has been built that uses charcoal as both a heat absorber and a wick. The still outperforms wick-type stills by 15%, is inexpensive, easy to build, and has the added benefits of low thermal capacity, light weight, and convenience of use. It is constructed up of a plastic outer rectangular body that allows salt water to percolate through a charcoal bed of particles that runs the length of the still, and a glass plate that covers the still at an optimal distance from the charcoal bed. An appropriate layer of sawdust is used to insulate the bottom of the still, which is fixed on a wooden frame with an adjustable inclination. The size range of the charcoal particles, the brine flow rate, and the still tilt to the horizontal has all been studied. The greatest productivities were reported at high flow rates with both coarse and intermediate particles, and at moderate flow rates with the finest charcoal. The three sizes produced almost identical productivities at low flow rates.