Techno-economic feasibility of ethanol production from fresh cassava tubers in comparison to dry cassava chips

Abstract

The use of unpeeled and peeled fresh cassava tubers for the production of ethanol indicated that the extent of liquefaction and saccharification is comparable to that of dry chips. However, the fermentation efficiencies were lower by about 13 and 2% with the use of fresh unpeeled and peeled tubers respectively. The use of unpeeled tubers can be ruled out due to viscous mass formation after saccharification and consequent resistance in solid-liquid separation. The viscosity of the hydrolysed slurry of peeled tubers was nearly the double and the recovery of hydrolysate was lower by 5% as compared to those with dry chips. Additional machinery, land and building are also essential for processing fresh tubers in harvest season. These will involve heavy depreciation and financial expenses due to idling over eight months when the plant will have to depend on dry chips. The studies establish that the gain obtainable due to differences in the cost of fresh tubers and dry chips is surpassed by various techno-economic factors.