Aussie sugar looks to go fossil fuel free

RESEARCHERS have received A$5.7m (US$4.4m) to test new biogas technologies with the aim to replace fossil fuels in Australia’s sugar industry.

The project, developed at the Queensland University of Technology (QUT), will use anaerobic digestion processes that use micro-organisms to digest sugarcane waste and surplus bagasse. Using a number of biochemical processes to break down the organic material in the absence of oxygen produces biogas, which can be upgraded to biomethane to replace diesel in both the farming and transportation of sugarcane, and replace coal used in factories.

Ian O'Hara, associate professor at QUT's Centre for Tropical Crops and Biocommodities, said: “While the sugar industry produces large amounts of bioenergy from sugarcane bagasse with surplus electricity exported to the grid, significant quantities of fossil-based fuels are used in the growing, harvesting and transport of sugarcane, and in certain factory operations.”

The three year project is funded by the Australian Renewable Energy Agency (ARENA) and partners including Griffith University, Sunshine Sugar and Utilitas Pty. It will involve scaling technologies from laboratory prototypes, to a renewable biocommodities pilot plant in Mackay, Australia, then onto factory scale.

“Trials will be conducted initially in laboratories at QUT and Griffith University, before being trialled at the Mackay pilot plant and on-site at the Broadwater Sugar Mill in northern NSW [New South Wales],” said O’Hara.

Australia’s sugar industry is worth around A$2bn. O’Hara said reducing greenhouse gas emitting fossil fuel usage would relieve a major cost burden to the industry.

“It is about turning a waste disposal problem into a bioenergy opportunity for the sugar industry and as a result reducing the carbon footprint of raw sugar production, and increasing income from bioenergy,” O’Hara continued.

He added that while sugarcane waste could be collected, separated, and burnt in cogeneration boilers for electricity production, research had shown it was generally not an economically viable option.