Depletion of the coal reserve in the main mine, which is the main fuel source for providing continuous operation of the Thermal Power Plant (TPP) Bitola, imposes the necessity of providing certain coal quantities from the new mines near to the old one. Since the new and old coal deposits have different coal quality, the processes of mixing of and inter-changing between coals from the mines, influence the system for coal preparation, in particular mills and their wheels, ducts for air-mixture, convective heat surfaces, etc. Regular reports the coal technical analysis continuously provide an insight of these changes in the coal quality and its influence of the boiler elements in Unit 1. In this paper, calculated is the Abrasion Index of coals following an empirical expression developed by Raask, where influential variables are the relative weight contents of quartz, pyrites and ash found in the coal sample. In accordance with the results, classification of the coals is performed, as well as diagrams that indicate the impact of coal ash content on the coal abrasiveness and its repercussion concerning the mills, associated system components and convective heat surfaces. Further, pointed out are several recommendations regarding improving the protection of the systems from coal abrasion.
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How to cite this paper
Influence of Coal Quality on Boiler Elements Abrasion
How to cite this paper: Lidija Joleska Bureska. (2021) Influence of Coal Quality on Boiler Elements Abrasion. Journal of Electrical Power & Energy Systems, 5(1), 1-7.