Study on effect of scale formation in evaporators of sugar industry using experimental and mathematical modeling

Abstract

This study focuses sugar factory evaporators in Sri Lanka. Multiple effect evaporators are employed in concentrating the clarified cane juice in sugar factories in Sri Lanka. Scale formation on heat transfer surfaces in sugar factory evaporators has a highly deleterious effect on specific energy consumption and production capacity. This thesis introduces combined experimental and mathematical modeling approach to study the effect of rate of scale formation in evaporators. Prior to develop mathematical model the rate of scale formation was experimentally investigated by analyzing evaporator scale, clear juice and syrup in two sugar factories in Sri Lanka. The model was developed using MATLAB software. The built mathematical model consists of two fouling phenomenal namely, particulate fouling and chemical precipitation fouling. The model shows the development of scale in each evaporator and temperature variation in each evaporator. The model also indicates the effect of following a scale reduction technique by comparing temperature variation in each evaporator before and after using a scale reduction technique.