Briquettes Obtained from Lignocellulosic Hemp (Cannabis sativa spp.) Waste, Comparative to Oak (Quercus robur L.) Ones

In order to expand the raw material base of lignocellulosic briquettes, and due to the shortage of wood materials, the use of lignocellulosic residues from the agricultural sector (such as hemp waste) became the main objective of this research. In order to state the significant differences between these briquettes, the lignocellulosic briquettes were obtained from hemp core waste and oak sawdust on the same hydraulic briquetting installation. The main properties of the two categories of briquettes were determined; we obtained a bulk density of about 450 kg/m3 for hemp core waste and 530 kg/m3 for oak sawdust. Also, the calorific values of the two categories of materials were about 18.2 MJ/kg and 17.5 MJ/kg, high calorific values (HCV) for hemp core waste/oak sawdust, and the calcined ash content was 5.8% for hemp and 0.8% for oak sawdust briquettes. As a general conclusion, through their physical–mechanical, calorific and chemical properties, it can be stated that the remains of the core obtained when obtaining hemp fibers can be used successfully to make fuel briquettes.