Pyrolysis characteristics and kinetics of pine trees

I&EC 41

Young-Hun Park, chemisonic@khu.ac.kr1, Jinsoo Kim, jkim21@khu.ac.kr1, and Seung-Soo Kim, sskim@kipeq.or.kr2. (1) College of Environment and Applied Chemistry, Kyung Hee University, 1 Seochen-dong Giheung-gu, Yongin, 449-701, South Korea, (2) Research Center, Korea Institute of Petroleum Quality, 653-1, Yangcheong-ri, Ochang-eup, Cheongwon-gun, Chungcheongbuk-do, 363-883, South Korea
Pine trees are one of the renewable resources in Korea, which can be converted to bio-oil, gas and char through pyrolysis. In this research, pyrolysis characteristics of pine trees were investigated using thermogravimetric analysis (TGA) at heating rates of 5~20ºC/min. Most of the materials were decomposed at the temperature range from 330ºC to 370ºC depending on the heating rate. Apparent activation energies increased from 145 kJ/mol to 302 kJ/mol, respectively, when the pyrolytic conversion increased from 5% to 95%. The kinetics of pine trees have been studied experimentally and mathematically. Experiments were carried out in a tubing reactor at a temperature of 330 ~ 370ºC and reaction times of 2 ~ 10 minutes. A lump model of combined series and parallel reactions for bio-oil and gas formation was proposed. Conversion data fitted first order kinetics for gas, bio-oil and pine (char). The kinetic parameters were determined by nonlinear least-square regression of the experimental data. It was found from the reaction kinetic constants that the predominant reaction pathway was A (pine) to gas (C1 ~ C4) formation rather than A to bio-oil formation at a temperature of 330~370ºC.