Thermal conversion processes of low-rank coals from Argentinean minefields

J. OCHOA; P. R. BONELLI; M. C. CASSANELLO; A. L. CUKIERMAN

Trends in chemical engineering

RESEARCH TRENDS

Lugar: Trivandrum ; Año: 2000 vol. 6 p. 43 - 66

0972-4478

Development of efficient clean technologies based on coal conversion processes, pyrolysis, gasification, for energy generation and chemicals production requires a deep knowledge of coal features and their variations with the processes course. Also, kinetic information of these processes is vital for proper design and modeling of commercial reactors. In spite of the vast literature on the subject, the behavior of a particular coal subjected to thermal conversion is still difficult to predict appropriately from reported data. Particularly, information of South American coals is rather scarce in the open literature and it is even more restricted for the low rank coals from the several coalfields mostly located in the Southwestern region of Argentine. In an updated context of the main experimental and theorethical advances related to the subject, this work presents own experimental data and discuss the behavior of two different types of low rank coals, subbituminous and high volatile bituminous, from the most extensive Argentinean minefields, examining especially: coals features; i.e., composition, structure, morphology and surface properties (specific surface areas, pore size distributions, surface fractal dimensions) and their modifications induced by pyrolysis at different operating conditions and mineral matter removal, the behavior of coal samples subjected to pyrolysis and the kinetics of this process, the kinetics of char samples gasification, using oxygen and carbon dioxide as gasifying agents, under kinetic and diffusional control conditions.