In this work, the production viability, physical, chemical and mechanical 10 properties of briquettes produced from mixtures of coffee shrub residues and pinewood, were 11 evaluated. The densification was carried out under constant operating conditions (temperature of 12 120 °C, pressure of 8.27 MPa) in a piston-press type laboratory-scale briquetting machine. 13Coffee shrub residues were mixed with pinewood in ratios of 25%, 50% and 75%. In addition, 14 reference briquettes of pure pinewood and of each type of coffee shrub residue were produced. 15To characterize the raw material, ash content, volatile matter, fixed carbon together with the 16 calorific value of produced samples, were measured. To characterize the suitability of the 17 briquettes produced: apparent density, energy density, tensile strength, and equilibrium moisture 18 content were determined. The highest values of energy density (19133 -19899 MJ•m -3 ), tensile 19 strength (415 -569 kgf), apparent density (1107-1163 kg•m -3 ) and favorable values of 20 equilibrium moisture content (9 -11 wt %) were obtained from a mixing ratio of 75% of 21 pinewood. The novel contribution of this research was to develop briquettes with appropriate 22 physical and mechanical parameters from new raw materials that could serve as sustainable fuel 23 sources for local firing systems. 24

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