Energy & Fuels, Vol.11, No.5, 972-977, 1997
Analysis of Pyrolysis Reactions of Various Coals Including Argonne Premium Coals Using a New Distributed Activation-Energy Model
A simple method presented by the author for estimating both f(E) and k(0) in the distributed activation energy model (DAEM) was applied to analyze the pyrolysis reactions of 19 different coals, including 8 Argonne premium coals, First, f(E) and k(0) for the changes in total volatiles were estimated using the thermogravimetric curves measured at three different heating rates for all the coals, It was found that f(E) curves were significantly dependent an coal rank, whereas the k(0) vs E relationships were found to be little dependent on coal rank, This suggests the similarity of the pyrolysis reactions for all the coals. For the Argonne premium coals, the peak E value of f(E) curves shifted from 215 to 275 kJ/mol in accordance with the coal rank, The validity of the method was clarified by comparing the predicted thermogravimetric curves with the experimental ones, Next, f(i)(E) and k(0i) for the changes in the evolution of gas components and tar were also estimated using the formation rates measured and the k(0) vs E relationships estimated above.
Keywords:DEVOLATILIZATION;KINETICS