Development and performance evaluation of briquettes made from a mixture of sugarcane bagasse and corn cobs

Abstract

The quest for alternative energy sources is gradually shifting from natural fossil fuel to alternative bio-resources especially agricultural waste products due to their reduced pollution risk and sustainability. The objectives of this study were therefore to characterize bagasse and corn cob wastes from selected sugarcane and maize varieties in Uganda, to develop the bagasse - corn cob briquettes using different mixture ratio and to characterize the bagasse-corn cob briquettes. The agricultural wastes investigated were corn cobs and sugarcane bagasse from selected corn and sugarcane varieties. The agricultural wastes were characterized by proximate and calorimetry analyses to determine the physical properties and heating values. In this study bagasse-cob briquettes were developed with cassava binder using low pressure. The briquettes were produced after carbonization of corn cobs and bagasse. The resulting bio-char was mixed with 50 grams of cassava starch binder for each mixture ratio of corn cobs and bagasse bio-char. Thermo-physical properties of the briquettes were determined using thermo-gravimetric analysis. A Bomb calorimeter was used to determine the higher heating values of the briquettes. Thermal characteristics were determined by observing the flame temperature during combustion. The mechanical integrity of the briquettes was determined using the drop test method. The higher heating values for the briquettes were between 20.3 and 26.5 MJ/kg. The result showed that the bagasse – cob briquettes (70:30, bagasse:corn cobs) combination had the most desirable properties with a higher heating value of 26.5 MJ/Kg. The study reiterates that corn residues and sugarcane bagasse good bio-fuels and should be encouraged to address the current energy shortfalls.