Effect of Flocculent On Scale Formation in Evaporators

ABSTRACT

 Scale formation has become a big burden to sugar manufacturing industries, especially in evaporators, this is because of the characteristics of cane juice which is allowed in evaporators. Evaporators are used to evaporate as much water as possible from the juice using exhaust steam from the powerhouse as the heating medium so as to concentrate the juice which is called syrup (that is the juice leaving the evaporator) and the juice entering the evaporator is termed as clear juice. Scale normally deposits inside the calandria tubes of the evaporators and this is brought by the constituents which are contained in the cane juice these include; insoluble solids, non-sugars, sulfates, gums, and waxes which are the major sources of scaling in the evaporators. The effect of scaling is to reduce the convective heat transfer between the tubes and the juice which in turn reduces the capacity of the evaporators hence reducing the efficiency of the evaporators. Therefore, this report focused on the immediate remedy of how to either stop or reduce scale formation in the calandria tubes of the evaporator so that evaporator efficiency is improved. Results show that the quantity (concentration) of flocculant used in the clarifier before allowing the juice to enter into evaporators this flocculant attracts insoluble solids forming heavy flocs which settle down the clarifier and allow only clear juice to enter the evaporator.