Abstract: The project investigated the combustion process of different heavy oils derived from Pinus massoniana wood, eucalyptus wood and wheat straw, and their kinetics characteristics using thermogravimetric analyzer. The result showed that the combustion process of all that the three heavy oils can be divided into three stages:1) room temperature to 300 ℃, mainly the evaporation of small molecular fraction; 2) 300-480 ℃, mainly the evaporation and combustion of volatile fraction; 3) above 480 ℃, the combustion of fixed carbon. The kinetics analysis indicated that the combustion process can be described as three consecutive first-order reactions. A quite good fitting of experimental data was obtained for all samples studied. In the stage of the evaporation and combustion of volatile fraction(300-480 ℃), the activation energy and ignition temperature of heavy oil derived from wheat straw were the lowest. Moreover the corresponding weight-loss rate of 0.188%/min was faster than other two kinds of heavy oils. Thus, heavy oil derived from wheat straw was the most flammable.

Key words: biomass, heavy oil, TGA, kinetic characteristics