EFFECT OF SOME ADDITIVES ON MASS-TRANSFER COEFFICIENT AT A VIBRATING HORIZONTAL SCREEN

The object of the present work is to study the effect of drag-reducing additives like Polyox WSR 301 and sodium lauryl sulfate (anionic surf actant) on the rate of mass transfer at a vibrating horizontal screen, an electrochemical technique which involved measuring the limiting cu rrent of the cathodic reduction of potassium ferricyanide. Variables s tudied were the concentration of polymer and surfactant, frequency of vibration and amplitude of vibration. II was found that a decrease in the mass transfer coefficient occurs in the presence of surfactant whi ch ranged from 3 to 61.8% depending on the concentration of the surfac tant. The addition of a Polyox leads to a decrease in the mass transfe r coefficient which ranged from 20 to 74.4% depending on the concentra tion of the polymer.