Experimental Evaluation and Techno-Economic Assessment of Biomass Briquettes Produced from Agricultural, Forestry and Poultry Residues

Abstract

This study investigated the physical, mechanical, fuel, and economic performances of 12 cylindrical biomass briquette formulations produced from agricultural residues, forestry sawdust, and animal waste binders. Corn straw, rice straw, crushed rice husk, mustard husk, peepal, shisham, and eucalyptus sawdust were blended with cow dung or poultry manure at a biomass-to-binder ratio of 70:30 (w/w) and compacted using a piston press. The briquettes were evaluated for dimensions, density, drying mass loss, shatter resistance, proximate composition, and calorific value. The density ranged from 0.583 to 1.488 g cm⁻³. The mixed sawdust/poultry manure formulation (SN07) resulted in the highest density, whereas the multi-residue formulation SN09 recorded the lowest drying mass loss (51.25%), lowest proximate moisture content (6.60%), and highest shatter index (98.70%). The volatile matter, ash, and fixed carbon contents ranged from 63.12–66.32%, 7.39–16.60%, and 10.11–21.39%, respectively. Shisham sawdust/cow dung briquettes (SN04) produced the highest calorific value of 3526.2 kcal kg⁻¹ (14.75 MJ kg⁻¹). At a nominal output of 400 kg h⁻¹, all formulations generated positive operating margins, and crushed rice husk/cow dung briquettes (SN03) yielded the highest estimated profit of INR 2.95 kg⁻¹. The results show that the best formulation depends on the intended priority: SN04 for heat output, SN07 for compactness, and SN09 for balanced handling, storage, and fuel characteristics.