№83-21
Dynamics of compound formation of trace elements and their distribution in the products of coal thermal treatment
S. Pinchuk1, https://orcid.org/0009-0002-3570-4131
T. Sharabura1 https://orcid.org/0009-0002-9175-6876
1Dnipro University of Technology, Dnipro, Ukraine
Coll.res.pap.nat.min.univ. 2025, 83:230–242
Full text (PDF)
https://doi.org/10.33271/crpnmu/83.230
ABSTRACT
Purpose. To investigate the nature and dynamics of trace elementscompound formation during coal thermal treatment and to determine their distribution among the resulting products.
The methods. The study is based on theoretical research using a software package for modeling multicomponent equilibrium heterogeneous systems.
Findings. The article presents the results of investigating the formation of trace elementscompounds of the minor group (Li, Ba, Ge, Ti, Zr, Mo, Cu, Zn) during coal thermal treatment using air and oxygen as oxidizing agents. It was established that all minor elements, except germanium and zinc, are present both in the molten ashand in the gas phase. The temperature intervals of transition of individual trace elements into the gas phase weredetermined, showing that zinc actively volatilizes at temperatures below 1500 °C. Whereas most other minor elements reach their maximum concentrations in the gas phase at temperatures above 1500 °C. The degree of transition of trace elements into the gas phase was quantitatively determined depending on the type of oxidizer. It hasdemonstrateda significantincrease in the volatility of lithium, titanium, and copper (up to 83–90% and 64–75%) and a less intensive transition of barium and molybdenum (22–32% and 35–75%). The temperature of condensation of trace elements compounds from the gas phase into the liquid phase was identified. Thisprovideda basis for designing systems to recover trace elements from gaseous products.
The originality. Further development was achieved in understanding the patterns of formation and distribution of trace elements of the minor group during the thermal treatment of coal, depending on the type of oxidizing agent and the treatment temperature.The temperature intervals and transition degrees of individual trace elements into the gas phase were determined. Theyenableda more precise characterization of their volatility and behavior during gasification. The results form a scientific foundation for optimizing technologies aimed at recovering valuable trace elements from the products of coal thermal treatment.
Practical implementation. The obtained results make it possible to optimize the operating conditions of coal thermal treatment in order to enhance the extraction of valuable trace elements and reduce their losses in coal ash residues. The identified regularities of trace elements transitions into gaseous and condensed phases can be applied to improve gas-cleaningsystems and to develop technologies for comprehensive use of Ukrainian coal, thereby increasing its economic and environmental efficiency.
Keywords: coal, trace elements, compounds, thermal treatment, oxidizer flow rate coefficient, gasification, molten ash, gas phase.
References
1. Stoiko, N. (2016). Green economy – the paradigm of sustainable development of agro-ecosystems in Ukraine. International Journal of New Economics and Social Sciences, 3(1), 90–99. https://doi.org/10.5604/01.3001.0010.4709
2. Li, H., Qu, W., Yang, Z., & Zhao, J. (2019). Trace element partition in coal combustion. Emission and Control of Trace Elements from Coal-Derived Gas Streams, 63–103. https://doi.org/10.1016/b978-0-08-102591-8.00003-9
3. Wiater, J., Wojciula, A., & Szatyłowicz, E. (2021). Trace Elements in Popular Coals Burnt in Low Power Boilers. Journal of Ecological Engineering, 22(11), 178–187. https://doi.org/10.12911/22998993/143287
4. Dai, S., Yan, X., Ward, C. R., Hower, J. C., Zhao, L., Wang, X., Zhao, L., Ren, D., & Finkelman, R. B. (2020). Valuable elements in Chinese coals: a review. Coal Geology of China, 60–90. https://doi.org/10.4324/9780429449369-5
5. Rezaee, M. (2012). Development of Strategies to Minimize the Release of Trace Elements from Coal Waste Source. Theses and Dissertations--Mining Engineering, 6. https://uknowledge.uky.edu/mng_etds/6
6. Ishkov, V.V., & Koziy, Е.S. (2017). About distribution of Co, Ni, Pb, Cr and V in coal layer c4 of mine «Samarskaya» of Pavlograd-Petropavlovsk geological and industrial district. Widening our horizons: International Forum for Students and Young Researchers, 64.
7. Vasylieva,I. V. (2023). Hermanii vuhilnykh plastiv ta porodnykh vidvaliv zakhidnoho Donbasu. Materialy XI naukovo-praktychnoi konferentsii «Mineralno-syrovynni bahatstva Ukrainy: Shliakhy optymalnoho vykorystannia». https://doi.org/10.59911/conf.2023.5
8. Bulat, A.F., & Baranov, V.A (2021). Analiz stanu hermaniienosnosti vuhillia Ukrainy. Heotekhnichni problemy rozrobky rodovyshch: Materialy XIKh mizhnarodnoi konferentsii molodykh vchenykh.
9. Zajusz-Zubek,E.,&Konieczyński,J. (2014). Coal Cleaning Versus the Reduction of Mercury and other Trace Elements’ Emissions from Coal Combustion Processes. Archives of Environmental Protection, 40(1), 115–127. https://doi.org/10.2478/aep-2014-0012
10. Minchener A. J. (2005). Coal gasification for advanced power generation. Fuel, 84(17), 2222–2235. https://doi.org/10.1016/j.fuel.2005.08.035
11. Schobert, H. (2022). Gasification. Rethinking Coal, 157–173. https://doi.org/10.1093/oso/9780199767083.003.0011
12. Dı́az-Somoano, M.,&Martı́nez-Tarazona, M.R. (2003). Trace element evaporation during coal gasification based on a thermodynamic equilibrium calculation approach. Fuel, 82(2), 137–145. https://doi.org/10.1016/s0016-2361(02)00251-x
13. Mishra S. K. (2023). Coal, Trace Elements. Encyclopedia of Mineral and Energy Policy. Berlin, Heidelberg, 184–186. https://doi.org/10.1007/978-3-662-47493-8_100
date of first submission of the article to the publication – 10/01/2025
date of acceptance of the article for publication after review – 11/08/2025
date of publication – 12/29/2025