Conceptual design of a cane white sugar factory offering maximum cogeneration

The increasing market demand for white sugar of high quality has led to the development of microfiltration and other techniques enabling the juice pur ification and sugar crystallization processes, in cane sugar factories to b e greatly simplified. When these techniques are applied together with high- pressure steam generators and condensing extraction turbogenerators, wholly electrified drives and single-line continuous process stations,the resulta nt white sugar factory can save at least 40% of the available bagasse durin g a 150 day crop, while still exporting approx. 35 kWh of electrical power per t of cane. The excess amount of bagasse can be baled during the crop an d be employed for firing the, power station during the off-season, generati ng an additional 77 kWh/t electrical power. In total, approx. 112 kWh/t of cane can be generated for export to the grid on a year-round basis, without employing any additional fuel or sophisticated methods like bagasse gasifi cation. The paper shows the conceptual design of such a factory, including an overa ll layout, summary. tables and schematics of the mass and heat balances, sh ort description of the main process features and cost estimate for a plant of 24,000 t/d capacity. At current world market white sugar prices and assu ming US$40 net revenue per MWh exported, the amount of export power generat ed will add approx 11% to the annual revenue of the factory due to sales of sugar and molasses. In a number of cane sugar producing countries this cou ld be an attractive proposition.