Mendeleyev University of Chemical Technology of Russia (Moscow, Russia):

E. N. Kuzin, Cand. Eng., Department of Environmental Engineering, E-mail: e.n.kuzin@mail.ru
N. E. Kruchinina, Dr. Eng., Head of Faculty of Biotechnology and Environmental Engineering, Head of Department of Environmental Engineering, E-mail: krutch@muctr.ru

The main goal of waste water treatment of metallurgical production is to return water to the circulating water supply system. The main pollutant of most process effluents are suspended substances, or suspensions. The key parameter for evaluating the cleaning efficiency is the residual content of suspended substances, which should not exceed 1–10 mg/l, depending on the technological purpose of the water. The most promising reagents for physic-chemical water treatment are complex coagulants that combine salts of two or more metals. Such reagents are free from the disadvantages of traditional coagulants, and large-scale wastes from various industries can be used as raw materials for their production. Complex coagulants based on aluminum salts, when aluminium is modified by the products of hydrolysis of titanium compounds, have proven to be highly effective in treatment processes of waste water of various origins. Testing of the complex coagulant obtained in the process of modifying of traditional aluminum sulfate by the products of hydrolysis of titanium compounds was carried out on waste water from gas cleaning plants for coal preparation, coking plants and electric arc furnaces for steelmaking. In terms of its effectiveness, the complex coagulant exceeded traditional aluminum sulfate and was as close as possible to the more expensive and modern aluminum oxychloride. The increased efficiency of the complex coagulant is due to flocculation and nucleation phenomena occurring on the surface of titanium compounds compared with aluminum sulfate. The complex coagulant was less sensitive to fluctuations in the pH of the treated water than pure aluminum sulfate. As a result of water treatment, it was possible to achieve a reduction in the content of suspended substances below 1 mg/l, which will positively affect the economy of the water treatment process. The rate of flake deposition and filtration of treated water, using complex coagulant, significantly exceeded both samples of the most common coagulants. Increased sediment density will reduce reagent costs for its dehydration, as well as the area required for its placement.

1. Drainage of settlements and industrial enterprises: directory for designer. Edited by V. N. Samokhin. 2nd edition. Moscow. Stroyizdat. 1981. 639 p.
2. Enlarged regulations for water consumption and water disposal for different industries. Moscow. Stroyizdat. 1982.
3. Kuznetsov M. S., Glazunov G. P. Erosion and soil protection. Manual. Moscow. Izdatelstvo MGU. 1996. 335 p.
4. Babenkov E. D. Water cleaning by coagulants. Moscow. “Nauka”. 1977. 356 p.
5. Komarova L. F., Kormina L. A. Engineering methods for environment protection. Technique of atmosphere and hydrosphere protection from industrial pollution. Manual. Barnaul. Izdatelstvo “Altay”. 2000. 395 p.
6. Ainetdinov R. M., Vasilyev A. L., Mukhina E. V. Practice of application of thin-walled dehydrating boxes for waste water purification at galvanizing production facilities. Sovremennoe stroitelstvo i arkhitektura. 2016. No. 1. pp. 5-6. DOI: 10.18454/mca.2016.01.1.
7. Zhao Y. X., Gao B. Y., Zhang G. Z., Qi Q. B., Wang Y., Phuntsho S., Kim J.-H., Shon H. K., Yue Q. Y., Li Q. Coagulation and sludge recovery using titanium tetrachloride as coagulant for real water treatment: A comparison against traditional aluminum and iron salts. Separation and Purification Technology. 2014. Vol. 130. pp. 19–27. DOI: 10.1016/j.seppur.2014.04.015.
8. Zhao Y., Phuntsho S., Gao B. et al., Preparation and Characterization of Novel Polytitanium Tetrachloride Coagulant for Water Purification. Environ. Sci. Technol. 2013. Vol. 47. pp. 12966–12975. DOI: 10.1021/es402708v.
9. Okour Y., Shon H. K., El Saliby I. Characterisation of titanium tetrachloride and titanium sulfate flocculation in wastewater treatment. Water Science and Technology. 2009. No. 59(12). pp. 2463–2473. DOI: 10.2166/wst.2009.254.
10. Zhao Y., Gao B., Shon H., Cao B., Kim J. H. Coagulation characteristics of titanium (Ti) salt coagulant compared with aluminum (Al) and iron (Fe) salts. J. Hazard. Mater. 2011. No. 185. pp. 1536-1542. DOI: 10.1016/j.jhazmat.2010.10.084.
11. Z hao Y. X., Gao B. Y., Cao B. C., Yang Z. L., Yue Q. Y., Shon H. K., Kim J.-H. Comparison of coagulation behavior and floc characteristics of titanium tetrachloride (TiCl₄) and polyaluminum chloride (PACl) with surface water treatment. Chem. Eng. J. 2011. No. 166. pp. 544-550. DOI: 10.1016/j.jhazmat.2010.10.084.
12. Kruchinina N. E., Kuzin E. N., Azopkov S. V., Chechikov I. A., Petrukhin D. Yu. Modification of titanium coagulant via sulphate method. Ekologiya i promyshlennost. 2017. No. 2. pp. 24–27. DOI: 10.18412/1816-0395-2017-2-24-27.
13. Kuzin E. N., Kruchinina N. E. Obtaining of the hardened forms of aluminium-silicate coagulants and their use in water purification and water treatment. Tsvetnye metally. 2016. No. 10. pp. 8–13. DOI: 10.17580/tsm.2016.10.01.
14. Galloux J., Chekli L., Phuntsho S., Tijing L. D., Jeong S., Zhao Y. X., Gao B. Y., Park S. H., Shon H. K. Coagulation performance and floc characteristics of polytitanium tetrachloride and titanium tetrachloride compared with ferric chloride for coal mining wastewater treatment. Sep. Purif. Technol. 2015. No. 152. pp. 94–100. DOI: 10.1016/j.seppur.2015.08.009/
15. Wang T.-H., Navarrete-López A. M., Li S., Dixon D. A., Gole J. L. Hydrolysis of TiCl4: Initial steps in the production of TiO₂. J. Phys. Chem. 2010. A 114 (28). pp. 7561–7570.
16. Luchinskiy G. P. Titanium chemistry. Moscow. Izdatelstvo “Khimiya”. 1971. 471 p.
17. Evmenova G. L. Development of the evaluation method for electric surfacial properties of coal dispersions. Vestnik KuzGTU. 2006. No. 5. pp. 51–53.
18. Shabanova N. A., Popov V. V., Sarkisov P. D. Chemistry and technology of nanodispersed oxides. Manual. Moscow. IKTs “Akademkniga”. 2007. 309 p.
19. Draginskiy V. L., Alekseeva L. P., Getmantsev S. V. Coagulation in purification technology of natural water. Moscow. Nauch. Izd. 2005. 576 p.
20. Getantsev S. V., Nechaev I. A., Gandurina L. V. Purification of industrial waste water by coagulants and flocculants. Moscow. ASV. 2008. 271 p.
21. Sulimova M. A., Sizyakov V. M., Litvinova T. E., Vasilyev V. V. On possibility of the use of metallurgical production wastes as a sorbent in the industrial water cycle. Chernye metally. 2016. No. 8. pp. 43-49.
22. Shon H., Vigneswaran S., Kandasamy J., Zareie M., Kim J., Cho D., Kim J. H. Preparation and characterization of titanium dioxide (TiO₂) from sludge produced by TiCl₄ flocculation with FeCl₃, Al₂(SO₄)₃ and Ca(OH)₂ coagulantaids in wastewater. Sep. Sci. Technol. 2009. Vol. 44. pp. 1525–1543. DOI: 10.1080/01496390902775810.
23. Algermissen D., Cankarevich C., Rekersdrees T., Sliephake H., Zehn T. Waste-free strategy at GMH based on four “R” principles. Chernye metally. 2018. No. 6. pp. 46–52.
24. Butorina I. V., Butorina M. V. Issues of implementing the best available technologies in the steel industry of the Russian Federation. Chernye metally. 2019. No. 1. pp. 43–48.