A doctorate study undertaken by Stellenbosch University Department of Process Engineering student Yuda Benjamin has found that the fibres of some varieties of sugarcane had the potential to boost the production of ethanol at a reduced cost.
Benjamin said a new scientific method developed as part his research in process engineering would aid the agricultural and biofuels sectors in identifying the most cost-effective sugarcane varieties for the production of ethanol.
Ethanol, which was produced from high-cost sugars, such as the sucrose found in sugarcane or the starch found in maize and wheat, was a promising alternative fuel that could potentially one day replace petrol.
Sugar cane has been identified by the South African Biofuels Strategy as having the biggest potential for ethanol production owing to its high productivity for each unit area of land compared to other crops.
However, Benjamin pointed out that one of the largest challenges faced by the sector in processing sugarcane fibre for ethanol was cost reduction.
Further, the new method could enable the use of an entire crop for ethanol production.
“Carbohydrates in sugarcane fibre (the residue left after sweet juice extraction) can be used to increase ethanol production because of its availability and the fact that it does not have an impact on food production,” he explained.
He said almost 90% of the carbohydrates could be extracted as simple sugars from the selected varieties, compared with 72% obtained from sugar cane already existing in the market.
The selected varieties also required less pretreatment and less enzymes during enzymatic hydrolysis.