Role of Water Activity of Liquid in Controlling Evaporation Rate of Low-Viscosity Liquids

Abstract

Viscosity of liquid is normally the most critical factor when operating an evaporator in an industrial process. This study shows that the dewatering capacity during evaporation for a low-viscosity peptone solution was reduced 40% for water activity (a w ) = 0.8 and 80% for a w = 0.45. Designers of evaporators should be aware of this phenomenon if the aim is to get a high degree of dry matter concentration in the liquid.