Characterization of fuel briquettes made from a blend of rice husk and palm oil mill sludge

Abstract

In this study, the physical and combustion properties of briquettes produced from a blend of palm oil mill sludge (POMS) and rice husk were investigated. The POMS was blended with rice husk in the ratios of 1:10, 1:5, 3:10, 2:5, 1:2, 3:5, 7:10, 4:5, 9:10, and 1:1. The result showed that the increased addition of palm oil mill sludge in rice husk sample significantly influenced (p < 0.05) the physical and combustion properties of the briquettes produced. The mean values recorded for the compressed and relaxed densities, durability rating, and the water resistance were all observed to increase while the relaxation ratio decreased. The moisture content, volatile matter, heating value, and the elemental composition of the rice husk-POMS briquette blend also increased while the fixed carbon and the ash content decreased. The 1:1 blending ratio presented the best quality within the range of the blending ratios considered. The physical properties of the briquette at the 1:1 blending ratio were compressed density (1044.93 kg/m3), relaxed density (498.55 kg/m3), relaxation ratio (2.10), durability rating (99.61 %), and water resistance (25.24 h). The combustion properties were moisture content (10.42 % w.b.), volatile matter (76.23 %), ash content (15.13 %), fixed carbon (8.64 %), heating value (21.68 MJ/kg), carbon (40.19 %), hydrogen (5.18 %), oxygen content (38.91 %), sulfur (0.39 wt%), and nitrogen (1.61 wt%).