Characterization and energy evaluation analysis of agro biomass briquettes produced from Gloriosa superba wastes and turmeric leave wastes using cassava starch as binder

The production chain of Gloriosa superba trimming (G) and turmeric leaf trimming (T) is a potential source of biomass residue, leading to high productivity and value-added product generation. Gloriosa superva waste and residues from turmeric leaf production are incinerated, which can lead to potential environmental problems. However, briquetting this waste would serve as an alternative process to produce a relatively high-energy fuel. In this study, Gloriosa superba waste and turmeric leaves were mixed in different ratios such as 0:100 (GT1), 25:75 (GT2), 50:50 (GT3), 75:25 (GT4) and 100:0 (GT5) with 20% cassava starch added as a binder. The produced briquettes were analysed for close-up analysis, physical properties, SEM analysis, elemental analysis, differential scanning calorimetry, thermogravimetric analysis and XRD analysis. The densities of the GT briquettes ranged from 840.33 to 1176.5 kg/m3. EDAX analysis revealed that the major elements in the briquettes samples of gloriosa superva waste and turmeric leaf waste were carbon and oxygen, 56.56% and 36.062%, respectively. The spontaneous combustion properties were reconfirmed by TGA and DSC analyses of the briquettes. The total calorific value of the briquettes produced varies between 11.66 and 15.64 MJ/kg. The briquettes had an ignition time of 3.3–4.0 s and a burning time of 20–28 min. Thus, briquettes made from Gloriosa superba waste and turmeric leaves containing 20% cassava starch proved to be an alternative energy source due to their low moisture and ash content and associated high calorific value.