Fundamental Study on Combustion Characteristics of Bio-briquette as Alternative Fuels for Domestic Coffee Stove

The aim of this study is to perform the effect of coffee waste blended in bio-briquette as an alternative fuel for domestic coffee stove. The sample of bio-briquette were blended with a variation of composition coffee waste, coal and polyvinyl acetate (PVAc) glue as a binder. The sample of bio-briquette was introduced in electric furnace with combustion atmosphere by using of 20% excess air condition. In the experiment, the mass reduction fraction, combustion rate, flame temperature of burning bio-briquettes was elucidated. The results obtained shows there are influenced of mass decreasing with an increasing of coffee waste blends, where the more of composition coffee wastes was added causes the faster of mass decreasing fraction of bio-briquette. The rate of combustion (K) increases with increasing percentage of coffee waste, where the largest K is obtained 6.05 (1 / second) in the composition of 90% coffee waste, while the smallest K of 4.55 (1 / second) is obtained in the composition of 30% coffee waste. The highest flame temperature occurs in the mixture of coffee waste 90% which is equal to 580 ° C and the lowest fire temperature occurs in the mixture of coffee waste 30% that is equal to 410 ° C.