Journal of Sustainable Metallurgy

, Volume 5, Issue 1, pp 97–106 | Cite as

Separation of Mill Scale from Flume Wastewater Using a Dynamic Separator Toward Zero Wastes in the Steel Hot-Rolling Process

  • Naiyang MaEmail author
  • Billi J. McDowell
  • Joseph Blake Houser
  • Marcelo W. Andrade
  • Dale E. Heinz
Research Article


Along with the production of hot-rolled steel, a large amount of mixture of mill scale, water, and oil is constantly generated. It is of great importance to thoroughly separate these components from one another to make them recyclable. In the current research work, an industrial trial was carried out at an ArcelorMittal hot-rolling mill for producing clean mill scale with negligible oil by separating the mill scale from flume wastewater using a dynamic separator. A slip stream of wastewater was continuously pumped from a roughing mill flume into a tangentially motivated dynamic separator. The mill scale particles settled to the bottom of the separator and continuously moved with the water into a classifier, where the mill scale was removed and dewatered. Results of the trial show that compared to the conventional practice of sedimentation and reclamation of the mill scale in the pits, using the new method, the mill scale is more than five times cleaner with negligible oil, and the effluent water is more than three times cleaner with much less total suspended solids. As a result, after separation with the new method, the mill scale and the wastewater are more recyclable. In addition, the new technology can also lead to recovery of more waste oil and significant reduction of oily mill scale sludge.


Mill scale Recycling Separation Oil Wastewater 



The authors wish to thank the ArcelorMittal management team for permission to publish this paper. Thanks also go to Luke A. Wood, David H. Gross, D. Gregory Hill, Blake E. Crisman, Homero Ortiz, William J. Sammon, Jeffrey A. Cox, and Jay Koch for their contributions in the development of this technology.

Compliance with Ethical Standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


  1. 1.
    Basabe VV, Szpunar JA (2004) Growth rate and phase composition of oxide scales during hot rolling of low carbon steel. ISIJ Int 44:1554–1559CrossRefGoogle Scholar
  2. 2.
    de Oliveira Lima Júnior S, Bellon JC, da Souza Júnior PA, da Silva Araújo FG, Cota AB (2010) Effect of processing parameters on scale formation during hot steel strip rolling. Mater Res 13:11–14CrossRefGoogle Scholar
  3. 3.
    Vlaicu G, Bancuta I, Stihi C, Gheboianu AI (2010) The study of scale formation on hot rolled ingots and billets. J Sci Arts 12:161–164Google Scholar
  4. 4.
    Bowers A, Eckenfelder WW (2003) Industrial wastewater and best available treatment technologies: performance, reliability, and economics. DEStech Publications Inc., LancasterGoogle Scholar
  5. 5.
    Ray S (2016) Principles and applications of metal rolling. Cambridge University Press, DelhiGoogle Scholar
  6. 6.
    Wallin KMF, Schlitter W (2007) Techniques for reclamation of water and scale. Iron and Steel Eng 74:64–68Google Scholar
  7. 7.
    Vervaet B, Avedian D, Pesci C (2010) New lubrication technology for the hot strip mill. Rev Métall 107:237–244CrossRefGoogle Scholar
  8. 8.
    Yu Q, Beard A (2014) Application of hot rolling lubrication on a reversing coil/plate mill. Iron Steel Technol: 52–60Google Scholar
  9. 9.
    Remus R, Monsonet MAA, Roudier Ð, Sancho LD (2013) Best available techniques (BAT) reference document for iron and steel production. Publications Office of the European Union, LuxembourgGoogle Scholar
  10. 10.
    Smil V (2016) Still the iron age: iron and steel in the modern world. Butterworth-Heinemannn, OxfordGoogle Scholar
  11. 11.
    Chatziaras N, Psomopoulos CS, Themelis NJ (2016) Use of waste derived fuels in cement industry: a review. Manag Environ Qual Int J 27:178–193CrossRefGoogle Scholar
  12. 12.
    Shatokha VI, Gogenko OO, Kripak SM (2011) Utilising of the oiled rolling mill scale in iron ore sintering process. Resour Conserv Recycl 55:435–440CrossRefGoogle Scholar
  13. 13.
    Więcek M, Mróz J (2014) Characteristics of fine-grid iron-bearing materials dusts, sludges, mill-scale sludges. In: Acta Metall. Slovaca Conf, pp 106–113Google Scholar
  14. 14.
    Siemens VAI (2007) Sinter solutions. Siemens web. Accessed 26 July 2018
  15. 15.
    Torftech (2018) Process reactor technologies. Torftech web. Accessed 26 July 2018
  16. 16.
    Liu B, Zhang SG, Tian JJ, Liu Y, Volinsky AA (2013) Recycle of valuable products from oily cold rolling mill sludge. Int J Miner Metall Mater 20:941–946CrossRefGoogle Scholar
  17. 17.
    Gaballah NM, Zikry AF, Khalifa MG, Farag AB, El-Hussiny NA, Shalabi MEH (2013) Production of iron from mill scale industrial waste via hydrogen. OJINM:23–28Google Scholar
  18. 18.
    Hu X, Yang Q, Ökvist LS, Björkman B (2016) Thermal analysis study on the carbothermic reduction of chromite ore with the addition of mill scale. Steel Res Int 87:562–570CrossRefGoogle Scholar
  19. 19.
    Kumar DS, Sah R, Sekhar VR, Vishwanath SC (2017) Development and use of mill scale briquettes in BOF. Ironmak Steelmak 44:134–139CrossRefGoogle Scholar
  20. 20.
    Michishita H, Tanaka H (2010) Prospects for coal-based direct reduction process. Kobelco Technol Rev 29:69–76Google Scholar
  21. 21.
    Mohanty MK, Mishra S, Mishra B, Sarkar S, Samal SK (2016) A novel technique for making cold briquettes for charging in blast furnace. IOP Conf Ser Mater Sci Eng 115:12–20Google Scholar
  22. 22.
    Paswan D, Malathi M, Minj RK, Bandopadhyay D (2015) Mill scale: a potential raw material for iron and steel making. Steel World 21:54–56Google Scholar
  23. 23.
    Saberifara S, Jafari F, Kardi H, Jafarzadeh MA, Mousavi SA (2014) Recycling evaluation of mill scale in electric arc furnace. J Adv Mater Process 2(3):73–78Google Scholar
  24. 24.
    Supino S, Malandrino O, Testa M, Sica D (2016) Sustainability in the EU cement industry: the Italian and German experiences. J Clean Prod 112:430–442CrossRefGoogle Scholar
  25. 25.
    Umadevi T, Brahmacharyulu A, Karthik P, Mahapatra PC, Prabhu M, Ranjan M (2012) Recycling of steel plant mill scale via iron ore sintering plant. Ironmak Steelmak 39:222–227CrossRefGoogle Scholar
  26. 26.
    Yang Q, Holmberg N, Björkman B (2009) EAF smelting trials of waste-carbon briquettes at Avesta works of Outokumpu stainless AB for recycling oily mill scale sludge from stainless steel production. Steel Res 80:422–428Google Scholar
  27. 27.
    Ma NY (2012) In-process separation of mill scale from oil at steel hot rolling mills. In: Zhang L et al (eds) EPD congress 2012. Wiley, Hoboken, pp 323–329CrossRefGoogle Scholar
  28. 28.
    Ma NY, Houser JB, Wood LA (2018) Production of cleaner mill scale by dynamic separation of the mill scale from the fast moving flume water at a hot rolling mill. J Clean Prod 176:889–894CrossRefGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  1. 1.ArcelorMittal Global R&D – East Chicago LaboratoriesEast ChicagoUSA
  2. 2.ArcelorMittal Burns HarborBurns HarborUSA

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