Production of fuel briquettes from olive refuse and paper mill waste

Some processes have been widely applied to biomass in order to take advantage of its energy potential. In particular, these processes are based on pyrolysis or gasification. In this study, briquetting was applied to olive refuse and paper mill waste to form fuel briquettes. For this purpose, the particle sizes of both biomass samples were decreased to −250 μm and then they were briquetted in a steel die under pressure between 150 and 250 MPa at ambient temperature. Effects of the moisture content of the biomass samples and briquetting pressure on the shatter index, compressive strength, and water resistance of the briquettes obtained were investigated. This study showed that the mechanical strength of the briquettes produced only from the olive refuse was not high enough. On the other hand, strong briquettes were produced using paper mill waste. When olive refuse was blended with fibrous paper mill waste, briquettes with sufficiently high mechanical strength could be produced. Burning profiles of the samples were derived applying derivative thermogravimetry technique under dynamic dry air atmosphere up to 1273 K with a heating rate of 40 K·min−1 and then combustion characteristics of the briquettes were compared.