THE DEVELOPMENT OF A PROTOTYPE FACTORY-BASED TRASH SEPARATION PLANT

Cane leaf residue (trash) left in the field after harvest constitutes a large, currently untapped source of available biomass. Harvesting the whole cane plant and subsequently separating the trash from the cane stalk in the cane supply entering the factory could potentially double the amount of fuel available for power generation. The Queensland Treasury (Office of Energy), Stanwell Corporation Ltd, and the NSW Sugar Milling Co-operative are funding the development by SRI of a commercial scale prototype cane cleaning plant. Funding by the Australian Greenhouse Office will assist with the installation of a fully commercial cane cleaning plant at Condong Mill. Preliminary trials carried out at SRI in July and August 2000 provided much of the basic information for the design of the prototype cleaning plant. Construction at Condong Mill of the prototype trash separation plant was completed by, and initial commissioning began, in early December 2000. Extensive testing and further development of the plant was continued through 2001. The performance testing program showed that the plant was able to achieve high levels of trash separation at low levels of cane loss (less than 1%), at commercial pour rates. Trials with an industry standard shredder indicated that the shredder could reduce the trash to approximate bagasse like consistency, but with a power requirement of the order of 12 kW/tonnes trash per hour. Conventional cyclone technology was shown to remove at least 99% of the air-borne trash which flowed from the cleaning chamber.