A NEW PARADIGM FOR ENHANCED INDUSTRY PROFITABILITY: POST-HARVEST CANE CLEANING

INCREASING HARVESTER POUR rate is a common strategy for reducing direct harvesting costs. However, high pour rates also reduce the effectiveness of harvester cleaning systems, and exacerbate cane loss at high extractor speeds. The value lost to these side effects has significantly impacted industry profitability over the past 15–20 years. Higher trashy extraneous matter (EM) levels associated with this increase in harvester pour rate increase fibre and impurity levels at the mill, resulting in reduced milling rates and extraction efficiency, increased sugar recovery losses in the process house and reduced sugar quality indicators. Simply returning to lower pour rates is not a viable strategy, as the cost of modern harvesting equipment requires high machine productivity to combat industry cost pressures. Post-harvest cane cleaning demonstrates potential to act as a ‘circuit breaker’ for this issue, allowing harvesters to remain highly productive (pour rates) and minimising cane loss in the field (reduced fan speeds), while also delivering a high quality cane product to the mill. The impact of incorporating post-harvest cleaning with high harvesting rates on recovered cane yield, load density and cane quality has been investigated at various sites in the Australian sugar industry. These trials have demonstrated the ability to avoid the losses associated with high fan speeds by adopting conservative fan settings while also achieving higher cane quality at the mill, improving total anticipated sugar recovery per hectare and the fibre:CCS ratio of cane milled. While the current payment systems deliver most benefit of enhanced sugar recovery to the grower, enhanced cane quality has significant potential benefit for the mill. While in the short term, management of the extracted trash is an issue, in the medium to longer term this is potentially a lucrative by-product.