Valorization of Bio-Briquette Fuel by Using Spent Coffee Ground as an External Additive

• Published in: Energies (Basel) 2020-01, Vol.13 (1), p.54
• Main Authors: Brunerová, Anna, Roubík, Hynek, Brožek, Milan, Haryanto, Agus, Hasanudin, Udin, Iryani, Dewi, Herák, David
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Ash; Biodiesel fuels; Biomass; Briquets; Bulk density; Calorific value; Coffee; Coffee industry; Composition; Durability; Hardwoods; Investigations; Lignin; Mass ratios; Mechanical properties; Particle size; Raw materials; Sawdust; Shavings; Waste materials
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en13010054

The present study investigates the quality changes of wood bio-briquette fuel after the addition of spent coffee ground (SCG) into the initial feedstock materials (sawdust, shavings) in different mass ratios (1:1, 1:3). Analysis of SCGs fuel parameter proved great potential for energy generation by a process of direct combustion. Namely, level of calorific value (GCV = 21.58 MJ∙kg−1), of ash content (Ac = 1.49%) and elementary composition (C = 55.49%, H = 7.07%, N = 2.38%, O = 33.41%) supports such statement. A comparison with results of initial feedstock materials exhibited better results of SCG in case of its calorific value and elementary composition. Bulk density ρ (kg·m−3) and mechanical durability DU (%) of bio-briquette samples from initial feedstock materials were following for sawdust: ρ = 1026.39 kg·m−3, DU = 98.44% and shavings: ρ = 1036.53 kg·m−3, DU = 96.70%. The level of such mechanical quality indicators changed after the addition of SCG. Specifically, SCG+sawdust mixtures achieved ρ = 1077.49 kg·m−3 and DU = 90.09%, while SCG + shavings mixtures achieved ρ = 899.44 kg·m−3 and DU = 46.50%. The addition of SCG increased wood bio-briquettes energy potential but decreased its mechanical quality. Consequently, the addition of SCG in wood bio-briquette has advantages, but its mass ratio plays an important key role.