Characterization of some Nigerian coal for effective power generation and industrial utility

Abstract

Large numbers of trace elements occur in coals used for coal power plants combustion. In order to assess the environmental impact of the coal fuel cycle, coal and coal ash samples need to be analyzed for a number of toxic and radioactive elements. Six coal samples from Ridi-Awe and Lafia (Nasarawa State), Garin Maiganga (Gombe state) Nigeria coal deposit were collected. The samples were subjected to gross calorific value determination, X-ray diffraction spectrometry, X-ray fluorescence spectroscopy to determine it suitability for power generation and industrial utility. Base on the laboratory analysis and results, it is observed that the gross calorific values of Awe are 29.18MJ/kg, 30.79MJ/kg. Lafia are 26.10MJ/kg, 25.10MJ/kg and Maiganga are 25.50MJ/kg, 24.21MJ/kg respectively. The XRF results indicates the presence of transition metals and some trace element but void of elements such as Arsenic, tin and tungsten which makes it environmental and health hazard friendly. The proximate analysis revealed that the % ash content of Awe, Lafia, and Maiganga is 87, 62, 79. % moisture content of Awe, Lafia, and Maiganga is 8.7, 16.3, 8.3 and % volatile matter content of Awe, Lafia, and Maiganga coals is 4.3, 21.7 and 12.7 whereas % fixed carbon of Awe, Lafia, and Maiganga 78.3,55.8 and 71.1 respectively. However, in terms of coal rank, the Awe is bituminous high volatile C, whereas Lafia and Maiganga coal are Subbituminous A, hence the reactivity and maturity of the coal decrease in the order of Awe (A) ˂ Lafia (L) ˂ Maiganga (M). The result shows that the coal samples are void of nitrogen and dangerous radioactive elements.