Ash residue beneficiation and processing technology

The issues connected with concentration of rare earth elements from ash residue of Chita Thermal Power Plant 2 using the methods of ore pretreatment and magnetic separation are studied. The applicability of the hydrochemical processing in recovery of rare earth elements from ash residue is determined. The processing technology is developed for ash residue, including pretreatment, magnetic separation, heavy medium separation or flotation, and leaching. The experimental research findings on the chemical composition of the test ash residue, its electromagnetic separation, as well as the contents of rare earth elements before and after leaching in nitrogen and hydrochloric acids, and in sulfuric and nitrohydrochloric acids are presented. The experimental results allow drawing a conclusion that leaching essentially reduces the content of rare earth elements in ash residue as these elements are transferred to solution and are made extractable later on. Regarding the ash residue from Chita Thermal Power Plant 2, titanium, strontium, gallium and rubidium exhibit the highest extraction ratios. The aim of the studies was mitigation of the environmental impact of ash residue from coal combustion at Chita Thermal Power Plant 2 by means of beneficiation and processing with manufacture of marketable products (rare earth elements).

Razmakhnin K. K., Khatkova A. N., Shumilova L. V., Nomokonova T. S. Ash residue beneficiation and processing technology. MIAB. Mining Inf. Anal. Bull. 2023;(10):122–135. [In Russ]. DOI: 10.25018/0236_1493_2023_10_0_122.

The study was supported by the Russian Science Foundation, Project No. 22-17-00040: Scientific Substantiation and Development of Environmentally Clean and Wasteless Technologies for Treatment of Natural and Manmade Mineral Raw Materials, 2022– 2023.

K.K. Razmakhnin¹, Dr. Sci. (Eng.), Assistant Professor, e-mail: constantin-const@mail.ru, ORCID ID: 0000-0003-2944-7642,
A.N. Khatkova¹, Dr. Sci. (Eng.), Professor, e-mail: alisa1965.65@mail.ru, ORCID ID: 0000-0001-6527-0026,
L.V. Shumilova¹, Dr. Sci. (Eng.), Professor, e-mail: shumilovalv@mail.ru, ORCID ID: 0000-0001-5991-9204,
T.S. Nomokonova¹, Graduate Student, e-mail: krutikova_1995@mail.ru, ORCID ID: 0009-0002-9096-864X,
¹ Transbaikal State University, 672039, Chita, Russia.

K.K. Razmakhnin, e-mail: constantin-const@mail.ru.

1. Myazin V. P. Methods for separating fly ash from coal combustion in Eastern Transbaikalia to extract rare elements from them. Khimiya tverdogo topliva. 2006, no. 1, pp. 75—80. [In Russ].

2. Arbuzov S. I., Ershov V. V., Potseluev A. A., Rikhvanov L. P. Redkie elementy v uglyakh Kuznetskogo basseyna [Rare elements in coals of the Kuznetsk basin], Kemerovo, 1999, 248 p.

3. Myazin V. P., Myazina V. I., Razmakhnin K. K., Shumilova L. V. Research of technogenic formations of the fuel and energy complex of Transbaikalia as complex geosystems and unconventional sources of mineral raw materials. Kulaginskie chteniya: tekhnika i tekhnologii proizvodstvennykh protsessov. T. 1 [Kulagin readings: techniques and technologies of production processes, vol. 1], Chita, ZabGU, 2017, pp. 152—159. [In Russ].

4. Zolotova I. Yu. Benchmarking of foreign experience in the utilization of solid fuel combustion products of coal thermal power plants. Innovacii i investicii. 2020, no. 7, pp. 123—128. [In Russ].

5. Heidrich C., Feuerborn H. J., Weir A. Coal combustion products: a global perspective. World of Coal Ash Conference. 2013, pp. 22—25.

6. Venktesh Sharma, Shalom Akhai Trends in utilization of coal fly ash in India: A review. Journal of Engineering Design & Analysis. 2019, vol. 2, no. 12-16, pp. 13—16.

7. Shavanov N. D., Konovalova N. A., Pankov P. P., Rush E. A. Study of the composition and properties of ash and slag mixtures for their utilization in the construction industry. Aktual'nye problemy tekhnosfernoy bezopasnosti. Sbornik tezisov nauchnykh trudov IV mezhdunarodnoy nauchno-prakticheskoy konferentsii studentov, aspirantov, molodykh uchenykh, prepodavateley, priurochennaya k 45-letnemu yubileyu kafedry «Promyshlennaya ekologiya i tekhnosfernaya bezopasnost'» [Actual problems of technosphere security. Collection of abstracts of scientific papers of the IV International scientific and practical conference of students, postgraduates, young scientists, teachers, dedicated to the 45th anniversary of the Department «Industrial Ecology and Technosphere safety»], Ul'yanovsk, UGTU, 2022, pp. 134—137. [In Russ].

8. Bespolitov D. V., Konovalova N. A., Dabizha O. N., Pankov P. P., Rush E. A. Influence of mechanoactivation of fly ash on the strength of ground concretes based on production waste. Ecology & Industry of Russia. 2021, vol. 25, no. 11, pp. 36—41. [In Russ]. DOI: 10.18412/18160395-2021-11-36-41.

9. Calderón Márquez A. J., Cassettari Filho P. C., Rutkowski E. W., de Lima Isaac R. Landfill mining as a strategic tool towards global sustainable development. Journal of Cleaner Production. 2019, vol. 226, pp. 1102—1115. DOI: 10.1016/j.jclepro.2019.04.057.

10. Huimin Chang, Haobo Tan, Yan Zhao, Ying Wang, Xuemei Wang, Yanxia Li, Wenjing Lu, Hongtao Wang Statistical correlations on the emissions of volatile odorous compounds from the transfer stage of municipal solid waste. Waste Management. 2019, vol. 87, no. 30, pp. 701—708. DOI: 10.1016/j.wasman.2019.03.014.

11. Sözer H., Sözen H. Waste capacity and its environmental impact of a residential district during its life cycle. Energy Reports. 2020, vol. 6, pp. 286—296. DOI: 10.1016/j.egyr.2020. 01.008.

12. Endzhievskaya I. G., Vasilovskaya N. G., Dubrovskaya O. G., Baranova G. P., Chudaeva A. A. The effect of mechanical activation on the stabilization of ash properties of Krasnoyarsk CHP. Journal of Siberian federal university. 2018, vol. 11, no. 7, pp. 842—855. [In Russ]. DOI: 10.17516/1999-494X-0099.

13. Fan J., Wang D., Qian D. Soil-cement mixture properties and design considerations for reinforced excavation. Journal of Rock Mechanics and Geotechnical Engineering. 2018, vol. 10, no. 4, pp. 791—797. DOI: 10.1016/j.jrmge.2018.03.004.

14. Matinde E., Simate G. S., Ndlovu S. Mining and metallurgical wastes. A review of recycling and re-use practices. Journal of the Southern African Institute of Mining and Metallurgy. 2018, vol. 118, no. 8, pp. 825—844. DOI: 10.17159/2411-9717/2018/v118n8a5.

15. Konovalova N. A., Pankov P. P., Petukhov V., Fediuk R., Amran Mugahed, Vatin N. I. Structural formation of soil concretes based on loam and fly ash, modified with a stabilizing polymer additive. Materials. 2022, vol. 15, no. 14, article 4893. DOI: 10.3390/ma15144893.

16. Semenov P. A., Uzunyan A., Davidenko A. M., Derevschikov A. A., Goncharenko Y. M., Kachanov V. A., Khodyrev V. Y., Meschanin A. P., Minaev N. G., Mochalov V. V., Melnick Y. M., Ryazantsev A. V., Vasiliev A. N., Burachas S. F., Ippolitov M., Manko V., Vasiliev A. A., Mochalov A. V., Novotny R. W., Tamulaitis G. First study of radiation hardness of lead tungstate crystals at low temperatures. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment. 2007, vol. 582, no. 2, pp. 575—580. DOI: 10.1016/j.nima.2007.08.178.

17. Sharonova O. M., Yumashev V. V., Solovyov L. A., Anshits A. G. The fine high-calcium fly ash as the basis of composite cementing material. Magazine of Civil Engineering. 2019, vol. 91, no. 7, pp. 60—72. DOI: 10.18720/MCE.91.6.

18. Vlasova V. V., Artemova O. S., Fomina E. Yu. Determination of directions for the efficient use of TPP waste. Ecology & Industry of Russia. 2017, vol. 21, no. 11, pp. 36—41. [In Russ]. DOI: 10.18412/1816-0395-2017-11-36-41.

19. Khudyakova L. I., Zalutsky A. V., Paleev P. L. Use of ash and slag waste from thermal power plants. XXI century. Technosphere safety. 2019, no. 4 (3), pp. 375—391. [In Russ]. DOI: 10.21285/2500-1582-2019-3-375-391.

20. Dave J. M. Disposal of fly ash — an environmental problem. International Journal of Environmental Studies. 1986, vol. 26, no. 3, pp. 191—215. DOI: 10.1080/00207238608710257.

21. Satpathy H. P., Patel S. K., Nayak A. N. Development of sustainable lightweight concrete using fly ash cenosphere and sintered fly ash aggregate. Construction and Building Materials. 2019, vol. 202, no. 2, pp. 636—655. DOI: 10.1016/j.conbuildmat.2019.01.034.

22. Ling Y., Wang K., Li W., Shi G., Lu P. Effect of slag on the mechanical properties and bond strength of fly ash — based engineered geopolymer composites. Composites Part B Engineering. 2019, vol. 164, pp. 747—757. DOI: 10.1016/j.compositesb.2019.01.092.

23. Krechetov O., Chernitsova A., Sharapova A., Terskaya E. Technogenic geochemical evolution of chernozems in the sulfur coal mining areas. Journal of Soils and Sediments. 2019, vol. 19, pp. 3139—3154. DOI: 10.1007/s11368-018-2010-7.

24. Barabanshchikov Y., Fedorenko I., Kostyrya S. Usanova K. Cold-bonded fly ash lightweight aggregate concretes with low thermal transmittance: Review. Advances in Intelligent Systems and Computing. 2019, vol. 983, pp. 858—866. DOI: 10.1007/978-3-030-19868-8_84.