Elektrane (2025) [pp. 460-469]
AUTHOR(S) / АУТОР(И): Lidija Joleska Bureska
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DOI: https://doi.org/10.46793/EEP25.460JB
ABSTRACT / САЖЕТАК:
Over the time, the best coal from our mines that were basis for the design and construction of the Thermal Power Plants in Republic of Macedonia was depleted. Now there currently exists only poor coal, coal with higher mineral matter content and lower calorific values making it of inferior quality compared to the original design specifications. Utilizing such coal in boilers present several disadvantages, including reduced efficiency, limited power output, increased strain on fuel supply and preparation systems, as well as slag and ash removal systems, heightened risk of operational failures, and other related issues. To address these challenges and enhance the coal quality, a strategy involving blending the existing coal with higher-quality coal is proposed usually. This paper delves into the selection process for coal blending, coal characteristics, and the operational implications on boiler when using different coal types. Through a comprehensive analysis encompassing calculation results, ash composition, and fusion temperatures, it is evident that the selection of coal for blending should not solely focus on increasing calorific value but also consider a broader range of characteristics to ensure optimal performance and efficiency in boiler operation. The last section illustrates the consequences of choosing inappropriate types of coal for mixing.
KEYWORDS / КЉУЧНЕ РЕЧИ:
coal, boiler, efficiency, slagging etc.
ACKNOWLEDGEMENT / ПРОЈЕКАТ:
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