The thermal kinetics of Huangling coal pyrolysis

By using the thermal gravimetric technique, the decomposition process of Huangling coal at three different particle size and heating rate was investigated. The experimental results show that the coal pyrolysis process is strongly affected by heating rate and particle size. As the heating rate increases, the final weight loss decreases and the DTG peak removes toward higher temperature. As the particle size decreases, the temperature at the point where the pyrolysis rate reaches the maximum increases and the maximum rate of weight loss decreases. The apparent activation energy values of the coal pyrolysis process were calculated by Kissinger´s and Ozawa´s methods. The calculation results demonstrate that the apparent activation energies of the 0.20-0.45mm size coal sample and the 0.45-0.90mm size coal sample are the lowest and highest respectively.