EVAPORATION OF A BINARY-LIQUID MIXTURE

An apparatus was designed to measure the evaporation rates of the components comprising a binary liquid mixture, from a horizontal surface, under conditions of turbulent air flow. Evaporation studies were conducted on the ethanol-water system. The effects on the evaporation rate of air velocity and liquid composition were investigated. The experimental evaporation rates were shown to depend on vapour pressure driving force. For the pure component, the evaporation exhibited a direct linear relation to air velocity. For ethanol-water mixtures the total and ethanol component evaporation increased with increasing ethanol concentration, while that of the water component remained virtually constant. Such behaviour was shown to be the direct result of the vapour pressure characteristics of the system.