Parameters of pulp drying in a high-temperature drier

Sugar factories dry their pressed pulp in so-called high-temperature driers. High-temperature drying operates by evaporation, the pressed pulp being dried in direct contact with a mixture of combustion and boiler exhaust gases and fresh air. This method represents the State Of the art in the drying of molassed pressed pulp. Other methods, such as steam drying and low-temperature drying, have been employed for many years alongside of high-temperature drying, but have not replaced it. Sudzucker's Warburg factory conducted a comprehensive measuring program during the 1999/2000 campaign to determine the factors influencing energy requirements. The rate of water evaporation and dry substance level of the molassed pressed pulp were found to be the major factors impacting on specific primary energy consumption and the temperature of the mixture of gases at the entrance of the drum. The specific energy consumption and drum entrance temperature rose as the rate of water evaporation and the dry substance content increased, and also with increasing dry substance content of the molassed pressed pulp at a constant rate of water evaporation.