No.1-7 Characteristics and Self-heating Behavior of Moatize Coals, Moatize Coal Basin, Mozambique

抄録

Mozambique has a great potential in terms of coal deposits, the most important is Moatize Coal Basin (MCB) located in Tete Province, Moatize district. The MCB has estimates reserves of about 2.5 billion tons, with thick coal seams allowing the open-pit exploitation. It is well known throughout the world that Moatize basin is a world class deposit for coking and thermal. However, recently, occurrences of spontaneous combustion are being resisted in both in situ coal seams and stockpiles of washed products (coking coal and thermal coal). Spontaneous combustion is a direct result of self-heating and it is a global issue affecting environment, economy and human health.

In this study, petrographic and chemical properties of samples of raw coal (in situ layers), coking coal and thermal coal were studied using image analysis through oil immersion microscopy and elemental and proximate analyzers (CHN, CS and TGA-DTA) respectively, to predict the propensity of self-heating. The microscopic characterization revealed important features such as changes in vitrinite reflectance, oxidation rims, micropores and cracks mainly on in situ coal and some signs of weathering and oxidation on thermal coal which are related to their reactivity and potential to self-heating leading later to spontaneous combustion