LAUSR

Abstract This study used Response Surface Methodology to investigate the effects of moisture content, temperature and applied pressure on the density, durability and impact resistance of millet bran briquettes. Furthermore, this study analyzed the optimum conditions for preparing the millet bran briquette using Generalized Distance Function. It was found that the density, durability and impact resistance of the millet bran briquettes increased as the temperature increased and as the moisture content decreased. As pressure increased, density, durability and impact resistance of the briquettes initially increased and then decreased. High-quality briquettes made of millet bran could be produced within the range of moisture content from 5% to 10%, temperature from 80 °C to 110 °C and pressure from 110 MPa to 130 MPa. The optimum moisture content, temperature and pressure were 5.4%, 101.9 °C, and 122.7 MPa, respectively. The density, durability and impact resistance under optimum conditions were 1.21 g cm−3, 95.7% and 99.64%, respectively. Millet bran possessed good fuel quality and could be successfully used as professional feedstock for producing solid biofuel.