Petrographical properties and unusual features of Kangal coals, Sivas-Turkey

Abstract

In Turkey, low-rank coal is used in three sectors: power generation industry, and household and commercial heating. Due to poor quality, coal is suitable for thermal power generation only. Kangal coal is of low-rank being mostly used in a thermal power station. Kangal coal basin, located in Eastern-central Turkey, formed in a Pliocene aged fresh-water lacustrine depositional environment and includes Kalburcayiri, Hamal and Etyemez Fields. Approximately 202.6 Mt of coal reserve, with calorific values between 1010 and 3420 kcal/kg are hosted in the area. Kalburcayiri Field is the only open pit production site in the basin. Fifty two channel samples were collected from different sites. The composite profile samples of the seams were taken into considerations. The content and depositional properties as well as some chemical and physical properties of the main coal seams are compared. Detailed organic petrographic and chemical analyses were applied for this study. All coal samples tend to have similar coal petrographic properties and were deposited in a lacustrine basin. Later, they were affected by faulting. As a result, there are variations in the properties and rank of the coal samples. The most abundant maceral group is huminite and the most abundant maceral is gelinite. Liptinite and inertinite contents of the coal are low and the maceral assemblage of the coals show extremely unusual. Broken and deformed maceral contents tend to be more abundant, considering the other Turkish coals. The maceral contents, textures and the unusual appearances imply that the coals were formed as in a hypautochtonous way. The reflectance measurements indicate the rank of the coals to be mostly as sub bituminous, although some chemical analyses exhibit inefficient results. (C) 2011 Elsevier B.V. All rights reserved.