Biomass Briquette Investigation from Pterocarpus Indicus Twigs Waste as an Alternative Renewable Energy

Pterocarpus indicus are commonly utilized as greening and found in Surabaya city. Since this plant exists in large
number, its fallen twigs become waste and aggravating the cleanliness of the Surabaya city. This study has investigated the possibility to utilize Pterocarpus indicus twigs waste as a renewable energy source. The study investigated the effect of tapioca (binding material) proportion toward the calorific value of briquette. The investigation was conducted using biomass composition ranges from 50% to 90% with 10% increase for each trial. The result suggests that the 90% biomass material-10% binding materials blends are the ideal composition for Pterocarpus indicus twigs waste briquette. Afterward, proximate and ultimate analyses were conducted to determine the viability of Pterocarpus indicus twigs waste as fuel. Another investigation was also conducted to discover the effect of particle size and compacting pressure on briquette quality. The parameters used for assessing briquette quality include flame temperature, ignition time, burning time, and combustion rate.
The result suggested that the value of flame temperature, ignition time and burning time increase with the increase of compacting pressure and smaller particle size. Combustion rate dropped as the pressure increase and particle size reduced. The best quality for briquettes of Pterocarpus indicus is acquired with a particle size of 60 mesh and compacting pressure of 2 MPa, which have a flame temperature of 515 °C, ignition time 251 seconds, burning time of 6590 seconds, and a combustion rate of 0.00303 gr/seconds.