Thermal decomposition, kinetics and combustion parameters determination for two different sizes of rice husk using TGA

Abstract

The present study concerns the thermal pyrolysis kinetics of sieved rice husk that was classified into two sizes (38–200 μm) and (200–1000 μm) by using Thermo-Gravimetric analysis (TGA) at different heating rate (HR) values under N₂. The thermal pyrolysis analysis was presented and kinetic parameters as activation energy (E), frequency factor (A), and order of reaction (n) were determined by using three different kinetic models. The effect of heating rate (HR) and particle sizes on the chemical kinetic parameters were presented and discussed. Direct method gave lower values of E and A compared to the integral method. Results showed that as particle size increases, values of the activation energy (E) and frequency factor (A) nearly increase. The combustion characteristic parameters such as ignition, burnout and peak temperatures and their corresponding times were determined. It found that larger sizes (200–1000 μm) have a relatively lower ignition temperature, higher activation energy and noticeably lower ignition times as compared to the smaller sizes (38–200 μm).