Abstract:
In this study briquettes prepared from four types of abundantly available crop residue (i.e., wheat straw, rice straw, maize straw and cotton sticks). These were optimized and tested to evaluate the enhancement in their properties including durability, bulk density, compression strength and calorific value. The briquettes were prepared using indigenously designed mechanical piston press briquettes forming machine. Briquettes formation was initially tested for three operational input material parameters i.e., moisture content, particle size and mould/die temperature from the four selected straws to find out their suitable ranges. Briquettes thus prepared were then statistically analyze using a 3-factor factorial design under CRD (completely randomized design) atthree levels of three independent variables including moisture content (15, 20 and 25%), particle size (9, 12 and 15 mm) and temperature (200, 250 and 300°C) respectively. Ultimately, the best quality and economical briquettes were achieved at 20% moisture content, 12mm particle size and at 300 °C temperature from all types of crop residue. It was also noted that the best quality briquettes were achieved from maize straw while rice straw produce least quality. Considering the calorific value, study showed a range of 15.3 –18.2 MJ/kgfor selected briquettes. Ultimate results of the study can provide the guidelines to the farmers. So, they can set the input parameters according to crop residue type to obtain the best quality briquettes with enhanced economic benefits.
