Biomass Torrefaction Reactor with PID Controller: Design and Thermal Assessment

Abstract

Thermal pretreatment of biomass is crucial before the material can be utilized in combustion applications due to its low energy density and inherent barriers. Therefore, pretreatment technologies such as torrefaction systems are essential for enhancing the properties of the fuel. This study aims to develop a fixed-bed torrefaction system supported by PID control for maintaining temperature within the torrefaction reactor. The PID controller is connected to an electric wire heating element and a K-Type thermocouple placed within the reactor to regulate temperature. The set-point temperature in the PID controller can be reached quickly after the heater is connected to the power source. Experiments were conducted to evaluate the torrefaction performance of palm kernel shells and bamboo chips under various temperature and residence time conditions. Temperatures were set at 200, 350, and 300°C respectively, while residence times were set to 10, 20, and 30 minutes for each biomass sample. The results demonstrate that the heating performance of the torrefaction system is suitable for conducting biomass torrefaction. The properties of palm kernel shells and bamboo chips were found to be similar to coal, suggesting that biomass torrefaction can be effectively utilized in combustion applications