Submitted to: Sugar Cane Research Report
Publication Type: Monograph
Publication Acceptance Date: 3/6/2009
Publication Date: 7/8/2009
Citation: Muir, B., Eggleston, G., Barker, B. The Effect of Green Sugarcane on Downstream Processing at Two Midlands Factories. Sugar Milling Research Institute Technical Report. No. 2051:1-34. Interpretive Summary: There is a worldwide shift to green from burnt cane harvesting due to environmental pressures against open field burning and the current trend to investigate cane trash (leaves and tops) as biomass for the fuel ethanol. Since the 1940s there have been factory trials all over the world on green cane processing but none have managed to shed light on the effect on downstream processing. This paper reports for the first time the dramatic effects of harvesting green and burnt billeted cane compared to whole-stalk cane. Green cane detrimentally affected purity, sugars, ash and color and the physical properties of samples right across the factory and in refinery sugar.
Technical Abstract: There is a worldwide shift to green cane from burnt cane harvesting. In many countries including the U.S. and South Africa, certain areas are changing to green cane harvesting due to public and environmental pressures against open field burning, increasing labor costs, and the current trend to investigate sugarcane trash as biomass for the production of bio-products. Since the 1940s there have been factory trials all over the world on green cane processing but none have managed to shed light on the effect on downstream processing beyond clarification. This paper reports on the effects of harvesting green billeted and/or whole-stalk sugarcane compared to burnt billeted and/or whole-stalk sugarcane at two factories situated in the Midlands area of South Africa, which operate either a tandem mill or a diffuser. Sufficient cane of each treatment was harvested and processed at each mill to purge the extraction plant of other cane. Trash tissues, direct analysis of cane (DAC), and bagasse samples in the front end were collected and analyzed. A bulk sample of mixed juice was transported to the SMRI in Durban and further processed in the SMRI pilot plant to clarified juice, syrup, “A” massecuites, molasses, raw sugar, and affinated sugar. Various differences in physico-chemical parameters including color and ash are presented.