Toxic properties and hydraulic activity of dump blast furnace slag

Metallurgical slags accumulate in large quantities. For further disposal, they must have the certain technical properties. Among the main factors there are chemical and mineral compositions of slags, which affect their final properties. Elemental composition of Zaporozhstal dump blast furnace slag, determined by electron probe microanalysis, makes it possible to characterize the slag fractions in terms of toxicity. Potassium, sodium, sulfur, chlorine, copper and titanium, which are not part of the minerals, are recorded by scanning electron microscope; this suggests that they are sorbed by mineral particles surface. The maximum content of potassium, sodium and titanium is typical for the 2.5 – 5.0 mm fraction. Slag contains an insignificant (less than 1 %) amount of metals – iron, titanium and copper, which belong to the third hazard class of the substance; this does not impede further use of the slag. The third hazard class of dump blast furnace slag has been identified. Volume activities and effective volume activities of granulometric slag fractions have been determined by gammaspectrometric method. ⁴⁰K, ²²⁶Ra and ²³²Th natural radio nuclides have been found. It has been proven that slag and its individual fractions belong to the first class of radiation hazard and can be used in construction without restrictions. Zaporozhstal dump blast furnace slag is characterized by high hydraulic activity with an increase in absorption of calcium oxide CaO over time. Dump blast furnace slag can be recommended for production of binders (Portland cement and slag Portland cement) in terms of combination of chemical parameters: to moderately hazardous production wastes of the first class of radiation hazard with manifestation of high hydraulic activity.

dump blast furnace slag, elemental composition, toxicity, hazard class of a substance, radioactivity, natural radionuclides, hydraulic activity

1. Motz H., Geiseler J. Products of steel slags an opportunity to save natural resources. Waste Management. 2001, vol. 21, no. 3, pp. 285‒293.

2. Khobotova E.B., Graivoronskaya I.V. Secondary use of metallurgical slags as sorbents in wastewater treatment. Chernye metally. 2019, no. 7, pp. 55–61. (In Russ.).

3. Tossavainen M., Engstrom F., Yang Q. etc. Characteristics of steel slag under different cooling conditions. Waste Management. 2007, vol. 27, no. 10, pp. 1335‒1344.

4. Baricová D., Pribulová A., Futáš P. etc. Change of the chemical and mineralogical composition of the slag during oxygen blowing in the oxygen converter process. Metals. 2018, vol. 8, no. 10, pp. 844‒857.

5. Ulubeyli G.C., Artir R. Sustainability for blast furnace slag: Use of some construction wastes. World Conference on Technology, Innovation and Entrepreneurship, Procedia ‒ Social and Behavioral Sciences. 2015, vol. 195, pp. 2191–2198.

6. Ochoa Díaz R. Blast furnace dust and phosphorous slag, new materials for use in road engineering. IOP Conference Series: Journal of Physics. 2017, vol. 935, article 012003.

7. Pribulova A., Futas P., Petrík J., Pokusová M. Comparison of cupola furnace and blast furnace slags with respect to possibilities of their utilization. Archives of Metallurgy and Materials. 2018, vol. 63, no. 4, pp. 1865‒1873.

8. Khobotova E.B., Kalmykova Yu.S. Environmental and chemical grounds for the utilization of blast furnace slag in the production of binders. Russian Journal of General Chemistry. 2012, vol. 82, no. 13, pp. 2180–2188.

9. Bobrova Z.M., Il’ina O.Yu., Khokhryakov A.V., Tseitlin E.M. Use of waste from mining and metallurgical industries for rational use of natural resources. Izv. Ural’skogo gosudarstvennogo gornogo universiteta. 2015, vol. 40, no. 4, pp. 16‒26. (In Russ.).

10. Kravchenko V.P. Assessment of hydraulic activity of blast-furnace slag. Vestnik Priazovskogo gosudarstvennogo tekhnicheskogo universiteta. Seriya: Tekhnicheskie nauki. 2010, no. 20, pp. 44‒47. (In Russ.).

11. Wang H., Cui S.P., Wang Y.L. Influence of cooling ways on the structure and hydraulic activity of blast furnace slag. Key Engineering Materials. 2015, vol. 633, pp. 234‒239.

12. Wang H., Cui S.P., Wang Y.L. Influence of process conditions on the structure and hydraulic activity of air-cooling blast furnace slag. Materials Science Forum. 2015, vol. 814, pp. 476‒482.

13. Chang P.-K., Lim Y. Effect of chemical composition on the latent hydraulic activity of blast furnace slag. Journal of the Korean Ceramic Society. 2000, vol. 37, no. 5, pp. 453‒458.

14. Bougara A., Lynsdale C., Milestone N.B. Reactivity and performance of blastfurnace slags of differing origin. Cement & Concrete composites. 2010, vol. 32, no. 4, pp. 319‒324.

15. Bellmann F., Stark J. Activation of blast furnace slag by a new method. Cement and Concrete Research. 2009, vol. 39, no. 8, pp. 644–650.

16. Kalmykova Yu.S., Khobotova E.B., Larin V.I. Rational ways of using dump blast furnace slag. Energetika: ekonomіka, tekhnologії, ekologіya. 2016, no. 1, pp. 44‒50. (In Russ.).

17. Molin F.D. Characterization of radioactivity arising from the integrated steelworks in the UK and assessment of occupational exposure situations. A thesis submitted in fulfillment of the requirements of the University of Surrey for the degree of doctor of philosophy, 2018, 281 p.

18. Ene A., Pantelică A. Characterization of metallurgical slags using low-level gamma-ray spectrometry and neutron activation analysis. Romanian Journal of Physics. 2011, vol. 56, no. 7-8, pp. 1011–1018.

19. Johnson W.J. The effect of chemical composition of blast-furnace slag on compressive strength and durability properties of mortar specimens. Graduate theses and dissertation, 2017, 83 p.

20. Kasina M., Michalik M. Iron metallurgy slags as a potential source of critical elements ‒ Nb, Ta and REE. Mineralogia. 2016, vol. 47, no. 1-4, pp. 15‒28.

21. Piatak N.M., Parsons M.B., Seal II R.R. Characteristics and environmental aspects of slag: A review. Applied Geochemistry. 2015, vol. 57, pp. 236‒266.

22. Sasmita C., Biswajit P., Manish K. Short-term leaching study of heavy metals from LD slag of important steel industries in Eastern India. Journal of Material Cycles and Waste Management. 2017, vol. 19, no. 2, pp. 851–862.

23. Proctor D.M., Fehling K.A., Shay E.C. etc. Physical and chemical characteristics of blast furnace, basic oxygen furnace, and electric arc furnace steel industry slags. Environmental Science and Technology. 2000, vol. 34, no. 8, pp. 1576‒1582.

24. Żak A., Isajenko K., Piotrowska B. etc. Natural radioactivity of wastes. Nukleonika. 2008, vol. 55, no. 3, pp. 387–391.

25. GOST 22688 – 77. Izvest’ stroitel’naya. Metody ispytanii [GOST 22688 – 77. Building lime. Test methods]. Moscow, 1977, 19 p. (In Russ.).

26. Khobotova E.B., Ignatenko M.I., Storchak O.G., Kalyuzhnaya Yu.S., Graivoronskaya I.V. Mineral composition of dump blast furnace slag. Izvestiya. Ferrous Metallurgy. 2019, vol. 62, no. 10, pp. 774‒781. (In Russ.).

27. DSanPіN 2.2.7.029–99. Gіgієnіchnі vimogi shchodo povodzhennya z promislovimi vіdkhodami ta viznachennya їkh klasu nebezpeki dlya zdorov’ya naselennya [DSanPiN 2.2.7.029 – 99. Hygienic requirements for industrial waste management of and determining their hazard class for public health]. Kiev, 1999, 21 p. (In Ukr.).

28. Khobotova E.B., Kalmykova Yu.S., Ignatenko M.I., Larin V.I. Natural radionuclides of blast furnace slags. Chernye metally. 2017, no. 1, pp. 23–28. (In Russ.).

29. Normy radiatsionnoi bezopasnosti Ukrainy (NRBU-97) i osnovnye sanitarnye pravila raboty s radioaktivnymi veshchestvami i drugimi istochnikami ionizirovannykh izluchenii [Radiation safety standards of Ukraine (NRBU-97) and basic sanitary rules for working with radioactive substances and other sources of ionized radiation]. Kiev, 1998, 159 p. (In Russ.).