Management of By-Products

The mills and refineries generally operate on a closed loop system, where inputs are retained and reused as much as possible. It is a system where by-products are value added to ensure the system is the most efficient to protect the economic and environmental sustainability of our operations. The 3 main by-products are Bagasse, Mill Mud and Molasses.

Bagasse is the remaining cane fibre after the juice has been extracted during the milling process and provides the fuel required to power the mills. Bagasse can also be used to manufacture paper.

2 x 30 mega watt power stations are being constructed in Murwillumbah and Broadwater in the north of NSW. Being powered by bagasse and other renewable fuels from vegetable origins, these power stations are currently the largest renewable energy project in Australia and are due for completion in 2007 and 2008. They will provide sufficient power to run the mills and send surplus energy to the national grid. Click here for further information.

Part of the milling and refining operations separates all foreign matter from the sugar. This foreign matter predominately contains dirt that comes in with the cane during the harvest and is known as ‘Mill Mud’. Ash from the boilers (remaining from the burning of the bagasse) is added to the mill mud and this is returned to the cane farms as a soil conditioner. Mill Mud is rich in nutrients and the use of mill mud allows farmers to significantly reduce their reliance on other forms of fertilisers. Mill mud is known to contain nitrogen, phosphorous, potassium, calcium and magnesium among others. Click here for further information.

The distribution of Mill Mud from the sugar mill back to cane farms is monitored to ensure correct application rates and that run-off containing excessive nutrients is reduced to protect the local waterways.

Molasses is the dark viscous syrup remaining after all the available sugar has been removed during milling and refining. Being a good source of nutrients, molasses is popular among livestock growers for use as a stock feed. Molasses is also used in distilleries for alcohol and can be further treated for use as an ingredient in the food industry.

Other solid waste, typical of large factories, is minimised. Recyclable material is separated from general waste and collected by 3rd party contractors. Other general waste is handled through the normal trade waste system operated by local councils.