Design Modification and Initial Performance Evaluation of a Multivariant Briquette Press for Multiple Biomass Feedstocks

Abstract

Biomass residues can be converted into solid fuel, but small-scale briquetting is often constrained by fixed molds and limited pressure adjustment. This study developed an initial multivariant briquette press concept using a modular mold and adjustable pneumatic compression, then evaluated briquettes produced from coconut-shell charcoal, corn-cob charcoal, and sawdust charcoal. Each formulation used 1,000 g of biomass charcoal and 100 g of tapioca binder (10% of charcoal mass). Three replicate samples per biomass were tested for moisture content, texture/hardness, and ash content. Mean moisture contents were 4.7142 +/- 0.0141% for coconut shell, 4.3147 +/- 0.5643% for sawdust, and 6.3146 +/- 1.1283% for corn cob. Coconut shell produced the highest relative texture/hardness value (3808.67 +/- 203.38) and the lowest ash content (3.1150 +/- 0.0433%). Sawdust had the lowest mean moisture content, whereas corn cob showed the lowest hardness and the greatest moisture variation. The results confirm that one press can form briquettes from different biomass feedstocks while also showing that biomass-specific control of pressure, particle size, moisture, and binder conditions is necessary for consistent product quality