Elektrane (2025) [pp. 361-374]
AUTHOR(S) / AUTOR(I): Ognjen Stamenković, Goran Stupar, Dragan Tucaković
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DOI: https://doi.org/10.46793/EEP25.361S
ABSTRACT / SAŽETAK:
Heat balance and aerodynamic calculations of milling plant are utilized for determining its performances which are of crucial importance for optimal operation of coal-fired boilers furnace. Assessing drying efficiency rate of raw coal to prepared coal dust influences the mill ventilation and, thus, overall mill maximum milling capacity. One of existing procedure for evaluating the quality of drying process is given in form of graphical dependencies of coal dust moisture content on mill gaseous mixture temperature and raw coal moisture content. These dependencies generated by use of testing-based data might be utilized for prediction in narrow scope of coal and milling plants types. Also, in most of the cases, they are limited to the mill gaseous mixture temperature of 150 oC which is lower than recommended values for impact-based milling plants. In this paper, equation for calculating coal dust drying efficiency rate is proposed. Equation has been validated by use of results of testing performed on several impact-based milling plants. Identification of influential parameters is performed on the basis of elementary thermodynamic consideration. Also, existing algorithm for heat balance calculations has been updated for the needs of incorporating modelled equation. More accurate results of drying efficiency rate would lead to the better predictions of maximum milling capacity and overall milling plant performances in various operational conditions.
KEYWORDS / KLJUČNE REČI:
drying efficiency rate, coal dust, fan mill, milling plants, milling capacity.
ACKNOWLEDGEMENT / PROJEKAT:
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