Contents of major and trace elements in feed coals from Turkish coal-firedpower plants

This preliminary study focuses on the determination and comparison of major and trace element concentrations in feed coals from ten Turkish coal-fired power plants (Cayirhan, Seyitomer, Tuncbilek, Orhaneli, Soma, Yatagan, Yen ikoy, Elbistan, Kangal and Catalagzi). Thirteen samples of feed coal were c ollected from the units of these plants and studied using proximate and ult imate analyses, X-ray powder diffraction, inductively coupled plasma-atomic emission spectrometry, inductively coupled plasma-mass spectrometry, and s canning electron microscopy with energy-dispersive X-ray microanalysis tech niques. The feed coals have high moisture (14-47%) contents, high ash (23-6 4%) yields, and a broad range of total sulfur contents (0.4-4.8%), and gros s calorific values (1370-4980 kcal/kg). The mineral matter of the feed coal s is mainly made up of clay minerals (smectite, illite, kaolinite/chlorite) , quartz, feldspar, calcite, dolomite, pyrite and gypsum. Moreover, some li gnites such as Seyitomer, Tuncbilek and Soma contain appreciable contents o f siderite; the Elbistan low contents of aragonite; the Cayirhan high conte nts of zeolites (clinoptilolite/heulandite and analcime). Most of the feed coals proved to be enriched relative to Cr, Cs, Mo, Ni, Rb, Th, U and V. Fu rthermore, concentrations of As, Co, Cu, Ga, Mn, Li, Sc, Sn, Ta, TI and som e rare earth elements in some feed coals exceed the currently available ran ges for most world coals. (C) 2000 Elsevier Science B.V. All rights reserve d.