Skip to main content
Top

Hint

Swipe to navigate through the articles of this issue

Published in: Metallurgist 1-2/2022

02-07-2022

Technology of Ash and Slag Waste Processing by Сhloridizing Roasting

Authors: N. K. Dosmukhamedov, E. E. Zholdasbay

Published in: Metallurgist | Issue 1-2/2022

Login to get access
share
SHARE

Abstract

Chloridizing processing of accumulated ash and slag waste of the Kazakhstan CHP plants has been studied. The possibility of separating iron from ash by magnetic separation to obtain a commercial iron-containing product (≈50% Fe) is demonstrated. It is shown that the residual iron content in the non-magnetic ash fraction is minimal (1.2%), while the aluminum content is about 98%. In the mullite composition, silica is mainly present in the non-magnetic ash fraction (≈97%). The silicon content in the non-magnetic fraction obtained after wet separation increased from 27.7 to 29.5 wt.%. It has been established that the complete decomposition of mullite occurs when the non-magnetic ash fraction is roasted at 1,100°C for 60 minutes, and the CaCl2 consumption is twice the stoichiometric value required for the decomposition of mullite. An increase in the degree of aluminum extraction into a cinder is caused by a change in the phase composition of ash during roasting, which occurs as a result of dehydration of low-solubility compounds. The resulting cinder contains the gelenite and anorthite phases, which are highly soluble in HCl. It has been found that the quantitative gelenite-to-anorthite ratio in the cinder, obtained under the optimal roasting conditions, is 5:1. For practical purposes, it is essential to provide for the charge mixing conditions during the ash roasting process in the presence of CaCl2, for example, by using a tubular rotary furnace. This will improve the contact between the ash particles and calcium chloride, while creating favorable conditions for the complete breakdown of mullite and formation of highly soluble aluminum compounds in the form of anorthite and gelenite.
Literature
1.
go back to reference E. Roth et al., “Distributions and extraction of rare earth elements from coal and coal by-product,” Proc. World Coal Ash Conf., Lexington, May 9–11 (2017). E. Roth et al., “Distributions and extraction of rare earth elements from coal and coal by-product,” Proc. World Coal Ash Conf., Lexington, May 9–11 (2017).
2.
go back to reference A. Dwivedi and M. Kumar Jain, “Fly ash — waste management and overview: a review,” Recent Research in Science and Technology, 6 (1), 30–35 (2014). A. Dwivedi and M. Kumar Jain, “Fly ash — waste management and overview: a review,” Recent Research in Science and Technology, 6 (1), 30–35 (2014).
3.
go back to reference T. G. Cherkasova, E. V. Cherkasova, A. V. Tikhomirova, A. A. Bobrovnikova, A. V. Nevedrov, and A. V. Papin, “Coal waste as a raw material for obtaining rare and trace elements,” Bull. Kuzbass State Tech. Univ., 185, No. 6, 185–188 (2016). T. G. Cherkasova, E. V. Cherkasova, A. V. Tikhomirova, A. A. Bobrovnikova, A. V. Nevedrov, and A. V. Papin, “Coal waste as a raw material for obtaining rare and trace elements,” Bull. Kuzbass State Tech. Univ., 185, No. 6, 185–188 (2016).
4.
go back to reference A. U. Akhmedyanov, K. Kirgizbaeva, and G. I. Turekhanova, “Recycling of waste (ash and slag) of industrial enterprises,” Materiály VIII mezinárodní vědecko — praktická konference “Aktuální vymoženosti vědy — 2012”, Díl 22, Technické vědy, Tělovýchova a sport: Education and Science, Praha (2012), pp. 37–40. A. U. Akhmedyanov, K. Kirgizbaeva, and G. I. Turekhanova, “Recycling of waste (ash and slag) of industrial enterprises,” Materiály VIII mezinárodní vědecko — praktická konference “Aktuální vymoženosti vědy — 2012”, Díl 22, Technické vědy, Tělovýchova a sport: Education and Science, Praha (2012), pp. 37–40.
5.
go back to reference Z. T. Yao et al., “A comprehensive review on the applications of coal fly ash,” Earth-Science Reviews, 141, 105–121 (2015). CrossRef Z. T. Yao et al., “A comprehensive review on the applications of coal fly ash,” Earth-Science Reviews, 141, 105–121 (2015). CrossRef
6.
go back to reference A. Zacco et al., “Review of fly ash inertisation treatments and recycling,” Environ. Chem. Lett., 12, 153–175 (2014). CrossRef A. Zacco et al., “Review of fly ash inertisation treatments and recycling,” Environ. Chem. Lett., 12, 153–175 (2014). CrossRef
7.
go back to reference J. Lopez-Cuevas, D. Long-Gonzalez, C. A. Gutierrez-Chavarria, et al., “Pech-Canul alumina extraction from Mexican fly ash,” Abstracts of the 18 th Int. Mater. Research Congress, Cancun, Mexico (2009), code 85958. J. Lopez-Cuevas, D. Long-Gonzalez, C. A. Gutierrez-Chavarria, et al., “Pech-Canul alumina extraction from Mexican fly ash,” Abstracts of the 18 th Int. Mater. Research Congress, Cancun, Mexico (2009), code 85958.
8.
go back to reference N. Nayak, “Aluminium extraction and leaching characteristics of Talcher thermal power station fly ash with sulphuric acid,” Fuel, 89 (1), 53–58 (2010). CrossRef N. Nayak, “Aluminium extraction and leaching characteristics of Talcher thermal power station fly ash with sulphuric acid,” Fuel, 89 (1), 53–58 (2010). CrossRef
9.
go back to reference P. W. Zhu, H. Dai, et al., “Aluminum extraction from coal ash by a two-step acid leaching method,” J. of Zhejiang University: Sci. A, 16 (2), 161–169 (2015). CrossRef P. W. Zhu, H. Dai, et al., “Aluminum extraction from coal ash by a two-step acid leaching method,” J. of Zhejiang University: Sci. A, 16 (2), 161–169 (2015). CrossRef
10.
go back to reference J. A. Eisele, “Bench-scale studies to recover alumina from clay by a hydrochloric acid process,” Industrial and Engineering Chemistry Product Research and Development, 22 (1), 105–110 (1983). CrossRef J. A. Eisele, “Bench-scale studies to recover alumina from clay by a hydrochloric acid process,” Industrial and Engineering Chemistry Product Research and Development, 22 (1), 105–110 (1983). CrossRef
11.
go back to reference C. Bazin, “Sequential leaching for the recovery of alumina from a Canadian clay,” Hydrometallurgy, 88 (1–4), 196–201 (2009). C. Bazin, “Sequential leaching for the recovery of alumina from a Canadian clay,” Hydrometallurgy, 88 (1–4), 196–201 (2009).
12.
go back to reference R. Boudreault, S. Alex, and F. Biasotto, “Extraction method of aluminum and iron from aluminous ores,” RF patent No. 2471010, IPC C 22 B21/00; appl. May 27, 2008; publ. December 27, 2012; Bul. 36. R. Boudreault, S. Alex, and F. Biasotto, “Extraction method of aluminum and iron from aluminous ores,” RF patent No. 2471010, IPC C 22 B21/00; appl. May 27, 2008; publ. December 27, 2012; Bul. 36.
13.
go back to reference Z. Guo, C. Wei, P. Zhang, J. Han, J. Chi, Y. Sun, and Y. Zhao, “Method for preparing metallurgical-grade alumina by using fluidized bed fly ash,” RF Patent No. 2510365, IPC C 01 F7/02; appl. April 27, 2011; publ. March 27, 2014; Bul. 9. Z. Guo, C. Wei, P. Zhang, J. Han, J. Chi, Y. Sun, and Y. Zhao, “Method for preparing metallurgical-grade alumina by using fluidized bed fly ash,” RF Patent No. 2510365, IPC C 01 F7/02; appl. April 27, 2011; publ. March 27, 2014; Bul. 9.
14.
go back to reference N. K. Dosmukhamedov, V. A. Kaplan, and G. S. Daruesh, “Innovative technology of integrated processing of ash from coal combustion,” Russ. Coal J., No. 1, 58–63 (2020). N. K. Dosmukhamedov, V. A. Kaplan, and G. S. Daruesh, “Innovative technology of integrated processing of ash from coal combustion,” Russ. Coal J., No. 1, 58–63 (2020).
15.
go back to reference N. K. Dosmukhamedov, V. A. Kaplan, E. E. Zholdasbay, G. S. Daruesh, and A. A. Argyn, “Extraction of iron into an iron-containing product from ash resulting from the combustion of Ekibastuz coal,” Ugol’, No. 1, 56–61 (2021). N. K. Dosmukhamedov, V. A. Kaplan, E. E. Zholdasbay, G. S. Daruesh, and A. A. Argyn, “Extraction of iron into an iron-containing product from ash resulting from the combustion of Ekibastuz coal,” Ugol’, No. 1, 56–61 (2021).
16.
go back to reference N. K. Dosmukhamedov, G. S. Daruesh, and E. E. Zholdasbay, “Specifics of ash components behavior under the chloridizing roasting conditions,” Mezhdunar. Zhurn. Prikl. Fund. Issled., No. 2, 91–98 (2020). N. K. Dosmukhamedov, G. S. Daruesh, and E. E. Zholdasbay, “Specifics of ash components behavior under the chloridizing roasting conditions,” Mezhdunar. Zhurn. Prikl. Fund. Issled., No. 2, 91–98 (2020).
Metadata
Title
Technology of Ash and Slag Waste Processing by Сhloridizing Roasting
Authors
N. K. Dosmukhamedov
E. E. Zholdasbay
Publication date
02-07-2022
Publisher
Springer US
Published in
Metallurgist / Issue 1-2/2022
Print ISSN: 0026-0894
Electronic ISSN: 1573-8892
DOI
https://doi.org/10.1007/s11015-022-01315-0

Other articles of this Issue 1-2/2022

Metallurgist 1-2/2022 Go to the issue

Premium Partners