Economic evaluation of Bursa-Orhaneli Lignite coalfield

Bursa-Orhaneli lignite coalfield is located in the North-West of Turkey. This coalfield has three sectors: Burmu, Çivili, and Sagirlar, having similar stratigraphic sequences in the northwest of Bursa Province. The mined coal seam is Miocene of age, and its thickness varies between 1.10-14.50 m. The pre-Neogene rocks in the area are made up of Palaeozoic aged metamorphic schists and marbles, and Upper Cretaceous aged ophiolites. The Neogene formations of detrital rocks with basal conglomerates, coal bearing marl and tuffites are found at the base, and volcanic basalt tuffs and andesite lava flows, at the top. The post-Neogene sediments are Pleistocene aged gravels and Holocene alluvium.The deposit has been worked as an open-pit mine in the Burmu and Sagirlar sectors and is going to be worked by underground mining methods in the near future. The chemical analysis have shown that the percentage of water is 22.66-27.30%, ash 24.57-44.39%, volatile matter 18.52-29.44%, fixed carbon 23.87-29.52%, and total sulphur 1.84-2.64% in the original coal, and its calorific value is 2010-3032 kcal/kg, whereas the air dried coal is composed of 5.51-10.41% water, 26.99-54.18% ash, 21.83-35.49% volatile matter, 28.10-36.03% fixed carbon, and 2.42-3.06% total sulphur, with calorific value of 2483-3938 kcal/kg. The proven and workable lignite reserves are 60,877,079 and 47,308,406 tonnes respectively. Stripping and production operations are made by a dragline, excavators and trucks. Mined coal is used both in domestic heating and the Orhaneli thermic power plant, which has a capacity of 1x210 MW