Energy Conversion and Management: X (Apr 2024)
Yield and energy outputs analysis of sawdust biomass pyrolysis
Abstract
The use of alternative energy sources has become increasingly imperative due to the increasing demand for global energy and the depletion of fossil fuel reserves. Biomass stands as a key player in addressing both current and forthcoming energy challenges, serving as a promising solution to fulfill the heightened need for energy resources. This study focused on investigating the impact of temperature variation during the pyrolysis process on the resultant yield (syngas, bio-oil, biochar), as well as examining the physicochemical characteristics of energy, and exergy output. To accomplish this, a cylindrical pyrolysis reactor was specifically designed and utilized for the experimentation, employing wood sawdust with particle sizes ranging from 0.1 to 30 mm as the primary feedstock. The experimental investigations and subsequent thermodynamic analyses were conducted through a temperature range of 250 to 450 °C, employing a heating rate of 10 °C/min. The findings revealed a direct correlation between the increase in pyrolysis temperature and the enhanced output of bio-oil and syngas. Optimal yields were observed at different temperature values, with bio-oil peaking at 450 °C (55 %) and biochar at 250 °C (60 %). Furthermore, bio-oil yield notably reached 47 % with particle sizes below 0.1 mm. The viscosity of the produced bio-oil averaged between 2.06 and 3.55 mPa s, while the density consistently approximated 1.05 g/cm3 across all cases. Detailed analyses including chemical and physical characteristics were conducted utilizing Fourier-transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GC–MS), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDX). The observation and quantification of CO, H2, CH4, and CO2 were part of the analytical process. This study shed light on the significance of temperature control in optimizing the output of valuable energy products from biomass pyrolysis, the potential for sustainable energy production, and the involved interplay of variables influencing the process.
