AUTOMATED PYROLYSIS-BASED MOBILE RETORT KILN FOR CHARCOAL PRODUCTION UTILIZING WASTE ENGINE OIL BURNER

Abstract

This study presents the design, fabrication, and performance evaluation of an automated pyrolysis‐based mobile retort kiln for charcoal production utilizing waste engine oil as fuel. The system employs an Arduino‐powered control panel with integrated sensors for real-time regulation of temperature, fuel flow, and air supply, ensuring precise control over the slow pyrolysis process even at operating temperatures around 270°C. Experimental trials conducted in a rural Philippine setting showed that each 12‐hour cycle consumed approximately 13.9 liters of waste engine oil and 2.6 kWh of electricity, achieving conversion efficiencies ranging from 15.63% to 22.15%, with an average of 18.14%. The system produced about 2.06 kg of charcoal per liter of fuel. Wood input was determined based on the Effective Kiln Wood‐Loading Volume; lower mass indicates drier wood, which enhances conversion efficiency, whereas a heavier input signifies wetter wood that requires additional energy for moisture evaporation. Emission analyses revealed reduced levels of carbon monoxide and particulate matter compared to conventional pit and earth‐mound methods. Economic evaluations demonstrated a rapid return on investment through low daily operating costs. Collectively, these results establish the system’s viability as a sustainable, efficient, and scalable alternative for rural charcoal production.