A comparative study on thermochemical decomposition of lignocellulosic materials for energy recovery from waste: Monitoring of evolved gases, thermogravimetric, kinetic and surface analyses of produced chars

Increased waste generation caused by the growth of urbanisation rate forces scientists and policymakers to rapidly develop and implement optimal waste management strategies. Since there are many ways to waste treatment and each waste material has different physicochemical properties, they should be investigated separately. This paper presents the results of an experimental investigation on the thermal decomposition of the spent coffee grounds (SCG) and textiles under various atmospheres using a vertical tube furnace. In the study, different analytical techniques are used, such as gas chromatography (GC), gas adsorption for surface area and porosity determination, Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Results indicated that SCG sample yielded more calorific pyrolytic gas (209.8 kJ/mol). than TEX (198.7 kJ/mol). O₂/CO₂ atmosphere fasten the fuel decomposition. Concerning biochar, it can be concluded that fast pyrolysis influenced their combustion performance, for example, its ignition temperature, TEX_slow (475.4 °C) > SGS_slow (470.5 °C) and TEX_fast (469.6 °C) > SGS_fast (415.0 °C), maximum weight loss rates and reactivity. This study will provide a better understanding of thermochemical degradation of waste and allows for developing optimal routes of waste utilisation.