Review of sugarcane trash recovery systems for energy cogeneration in South Africa

Biomass is a potential sustainable source of energy. Approximately one-third of the energy available from sugarcane is contained in the tops and leaves (trash), which are generally either burnt prior to harvesting or are not recovered from the field. Based on results reported in the literature and assuming a 50% trash recovery efficiency, it is estimated that 1.353 million tons of trash is available annually for cogeneration in South Africa, which could potentially produce 180.1MW over a 200 day milling season. Studies in Brazil and Australia have shown that the most efficient way of recovering the tops and leaves for cogeneration of power at sugar mills is to use a chopper harvester with the separation of cane stalks and trash on the harvester either fully or partially turned off. In South Africa more than 90% of the sugarcane crop is burnt and manually harvested and hence new systems are proposed to recover the trash and to transport the material to the mill.