Study of the interrelations of blowing parameters, options of electric influence and nature of liquid spraying by physical modeling

The main and decisive factor of blowing in oxygen converters  is interaction of high-speed oxygen jet with a molten bath. The features of this interaction determine hydrodynamics and level of metal  losses with slopping and spitting. Their study is most accessible with  cold modeling. The paper presents results of laboratory studies on the  physical model of a 160 ton converter manufactured at a scale of 1:30  to study the influence of blowing modes on character of liquid spraying.  It is blown through a lance with five nozzle tips at 10 horizons in model  height on three zones of working volume of converter model: area near  lance, area near the wall and out-of-model area. That in practice corresponds to intensity of formation of skull on the lance, on converter  mouth and on elements of the fume gas collecting system. It was found  that the total amount of liquid sprays carried out of the model is extreme  and depends on level of lance position, with a noticeable decrease in  the amount of sprays at zero height above the liquid, and above certain  values. The possibility of reducing of the intensity of splashing formation and the level of liquid loss within the investigated zones was  determined by applying a low-voltage electric potential: with negative  polarity in the area near the lance and near the walls, and with positive  polarity – out of the model.  It was revealed that beginning of practical  influence of the potential and the maximum value of “useful” power  allocated in the sublance zone is determined by specific combination of  pressure before the nozzle and the level of tip of the lance: the higher  the pressure in front of the nozzle is, the higher lance position is needed  to reach maximum values of “useful” power. The experiments, conducted on physical model during blowing of saline solutions with gases  at using of electric potentials, have shown possibility of extending the  scope of developed method to processes not related to metallurgy.

1. Kharakhulakh V.S., Lesovoi V.V., Mel’nik V.M. Condition of steelsmelting production at the enterprises of “Metallurgprom” and prospects of its development till 2015. Metallurgicheskaya i gornorudnaya promyshlennost’. 2010, no. 7, pp. 4–9. (In Russ.).

2. Okhotskii V.B. Hydrodynamic model of BOF. Izvestiya VUZov. Chernaya metallurgiya = Izvestiya. Ferrous Metallurgy.  1996,  no.  3, pp. 10–14. (In Russ.).

3. Chernyatevich A.G., Shishov B.I. Distribution of oxygen streams  in working space of BOF. Izvestiya VUZov. Chernaya metallurgiya = Izvestiya. Ferrous Metallurgy. 1981, no. 1, pp. 28, 29. (In Russ.).

4. Chernyatevich  A.G.,  Zarvin  E.Ya.,  Volovich  M.I.  Observation  through the transparent wall over the behavior of converter bath during blowing. Izvestiya VUZov. Chernaya metallurgiya = Izvestiya. Ferrous Metallurgy. 1975, no. 2, pp. 37–42. (In Russ.).

5. Yavoiskii A.V., Taranovskii G.А. Research, development and application of gas streams in converter processes of steel production. In:  Problemy teorii i praktiki staleplavil’nogo proizvodstva [Problems  of the theory and practice of steel production]. Moscow: Metallurgiya, 1991, pp. 126–148. (In Russ.).

6. Medzhibozhskii  M.Ya.  Osnovy termodinamiki i kinetiki staleplavil’nykh protsessov [Fundamentals of thermodynamics and kinetics of steel-smelting processes]. Kiev: Vishcha shkola, 1979,  277  p. (In Russ.).

7. Baptizmanskii V.I. Teoriya kislorodno­konverternogo protsessa [Theory of BOF process]. Moscow: Metallurgiya, 1975, 376 p. (In Russ.).

8. Kolpakov S.V., Starov R.V., Smoktii V.V., Lebedev V.I. etc. Tekhnologiya proizvodstva stali v sovremennykh konverternykh tsekhakh [Technology of steel production in modern converter shops]. Moscow: Mashinostroenie, 1991, 464 p. (In Russ.).

9. Okhotskii V.B., Kozachenko D.A. Metal yield in steel smelting process. BOF. Metallurgicheskaya i gornorudnaya promyshlennost’.  2006, no. 2, pp. 17–19. (In Russ.).

10. Okhotskii V.B. Emissions at converter processes. Metall i lit’e Ukrainy. 2013, no. 3, pp. 26–32. 

11. Semykin S.I., Polyakov V.F., Borisov Yu.N. etc. Application of low  power electric energy at steel smelting in converters. In: Trudy pervogo s”ezda metallurgov, Moskva, 12 – 15 noyabrya, 1992 [Proc.  of the 1st Congress of Metallurgists, Moscow, November 12–15,  1992]. Moscow: Chermetinformatsiya, 1993, pp. 55–57. (In Russ.).

12. Martin M., Rendueles M., Diaz M. Hydrodynamics and mass transfer in steel converters using cold models. In: Proceedings 5th European Oxygen Steelmaking Conference. 26­28 June 2006, Aachen, Germany. Dusseldorf: Verlag Stahleisen GmbH, 2006, pp. 577–580.

13. Martin M., Diaz M. Gas-liquid and gas-liquid-liquid reactors with  top and bottom blowing: I. Fluid dynamic regimes. Chemical Engineering Communications. 2002, vol. 189, Iss. 4, pp. 543–570.

14. Mats Brämming, Bo Björkman. Avoiding sloppy BOS process behavior. Iron & Steel Technology. 2010, vol. 7, no. 11, pp. 66–75. 

15. Brahma Deo, Aart Overbosch, Bert Snoeijer etc. Control of slag formation, foaming, slopping, and chaos in BOF. Transactions of the Indian Institute of Metals. 2013, vol. 66, Iss. 5, pp. 543–554.

16. Stepanov V.P. Mezfaznye yavleniya v ionnykh solevykh rasplavakh [Interphase phenomenon at ionic soline melts]. Ekaterinburg: Nauka, 1993, 316 p. (In Russ.).

17. Stepanov E.M., D′yachkov B.G. Ionizatsiya v plameni i elektricheskoe pole [Ionization in flame and electrical field]. Мoscow: Metallurgiya, 1968, 312 p. (In Russ.).

18. Vanyukov A.V., Kirillin I.I., Zaitsev V.Ya. Double electric layer at  the interface of metallurgical melts. Tsvetnye metally. 1970, no. 3,  pp. 22–26. (In Russ.).

19. Sharov A.F., Stepanov V.P. Dependence between the charge density  and the leap of potential at the interface between liquid metals and  molten salts. Trudy instituta elektrokhimii AN SSSR. 1974, no. 21,  pp. 39–43. (In Russ.).

20. Semykin S.I. Research in 1,5 – t converter of oxidation character of  hot metal impurities at imposition of low voltage to the steel smelting bath. Fundamental’nye i prikladnye problemy chernoi metallurgii. 2005, no. 11, pp. 96–105. (In Russ.).