Energy efficiency improvement of cane sugar factories by drying of bagasse with superheated steam

Bagasse drying with superheated steam offers the advantage of producing approximately 15% more power than with a conventional co-generation plant. Based on a fibre content of 14% on cane a power export of up to 140 kWh/t cane is achievable compared to 122 kWh/t cane in case of a conventional highly efficient co-generation plant. The operational results of a 12 t/h bagasse drier in Australia are briefly described and a concept of integrating a bagasse steam drier system in a modern highly energy efficient cane sugar plant is explained. This encompasses changes in the boiler capacity, turbogenerators and evaparation plant lay-out. Based on power export prices in the range of USD50–85/MWh the payback period of a bagasse steam drier system can be estimated with 3–6 years.