Studying working space form effect on electrolyzer MHD parameters at aluminum production

The article deals with the study of the influence of the electrolysis cell working space form (in particular, the hearth accretion buildup length) on the bath magnetohydrodynamic parameters under aluminum production by the electrolysis of cryolite-alumina melts. The methods of mathematical modeling with the use of Blums v5.07 and MHD-Valdis programs were applied to analyze the effect of the accretion buildup length on the electrolysis bath magnetohydrodynamic (MHD) stability resource and the maximum density of the horizontal currents arising in the metal melt. The models of the S-8BM electrolyzer were built in the program Blums v5.07 for different hearth accretion lengths (depending on the service life of the electrolysis cell). 13 variants of horizontal current distribution were calculated for the baths with accretion buildup length from 30 cm to 150 cm with a 10 cm pitch. The obtained results are presented in the form of dependences of the MHD stability resource and maximum density of horizontal currents on the accretion buildup length formed in the electrolysis cell during operation. The results of calculated variants of horizontal currents distribution have showed that high horizontal currents can be formed both in the case of accretion buildup spreading under the anode and in the case of a small just originating accretion buildup. Dependences of the MHD stability resource and maximum current density in the metal melt on the accretion buildup length were obtained. It has been determined that the probability of MHD instability occurrence in S-8BM electrolysis cells during the accretion buildup originating is much lower (the difference in the values of MHD stability resource is 500 mV) than in the period when the electrolyzer has long spreading beyond the anode projection accretion buildups.

primary aluminum production, electrolysis cell, electrolysis bath service life, workspace form, magnetohydrodynamics (MHD), mathematical modeling

1. Mann V., Buzunov V., Pitercev N., Chesnyak V., Polykov P. Reduction in Power Consumption at UC Rusal's Smelters 2012-2014 // Light Metals. 2015. Р. 757-762.

2. Бегунов А.И. Газогидродинамика и потери металла в алюминиевых электролизерах. Иркутск: Изд-во Иркутского университета, 1992. 286 с.

3. Kdkhodabeigi M., Saboohi Y. A New Wave Equation for MHD Instabilities in Aluminum Reduction Cells // Light Metals. 2007. Р. 345-349.

4. Sørlie M., Øye H. Cathodes in Aluminium Electrolysis (3 rd edition). Dusseldorf: Aluminium-Verlag. 2010. 662 р.

5. Urata N. Magnetics аnd Metal Pad Instability // Light Metals. 1985. Р. 581-589.

6. Segatz M., Droste С. Analysis оf Magnetohydrodynamic Instabilities in Aluminium Reduction Cells // Light Metals. 1994. Р. 313-322.

7. Davidson P.A., Lindsay R.I. A New Model Of Interfacial Waves in Aluminium Reduction Cells // Light Metals. 1997. Р. 437-444.

8. Droste C., Segatz M., Vogelsang D. Magnetohydrodynamics Instability Analysis in Reduction Cells // Light Metals. 1998. Р. 419-427.

9. Davidson P.A., Lindsay R.I. Stability of interfacial waves in aluminum reduction cells // J. of Fluid Mechanics, 362. 1998. P. 273-295.

10. Panaitescu A., Moraru A. Research on the Instabilities in the Aluminum Electrolysis Cell // Light Metals. 2003. Р. 359-366.

11. Радионов Е.Ю., Немчинова Н.В., Третьяков Я.А. Моделирование магнитогидродинамических процессов в электролизерах при получении первичного алюминия // Вестник Иркутского государственного технического университета. 2015. № 7 (102). С. 112-120.

12. Bojarevics V. Practical modelling of MHD stability in aluminium reduction cells // Цветные металлы и минералы-2016: сборник тезисов докладов Восьмого междунар. конгресса: сборник тезисов докладов Восьмого междунар. конгресса (г. Красноярск, 13-16 сентября 2016 г.). Красноярск, 2016. C. 61.

13. Bojarevics V. MHD of Aluminium Cells with the Effect of Channels and Cathode Perturbation Elements // Light Metals. 2013. Р. 609-614.

14. Shaoyong R., Feiya Y., Dupuis M., Bojarevics V., Jianfei Z. Production Application Study on Magneto-hydro-dynamic Stability of a Large Prebaked Anode Aluminum Reduction Cell // Light Metals, 2013. Р. 603-607.

15. Пингин В.В., Третьяков Я.А., Радионов Е.Ю., Губин А.А. Исследование влияния положения анодной рамы на запас МГД-стабильности электролизера С-8БМЭ // Цветные металлы-2012: сборник научных статей (г. Красноярск, 5-7 сентября 2012 г.). Красноярск, 2012. С. 431-434.

16. Пат. № 2517623, РФ, МПК C25C 3/12 Способ обслуживания алюминиевого электролизера с самообжигающимся анодом / В.В. Пингин, Я.А. Третьяков, А.А. Губин, Е.Ю. Радионов; заявитель и патентообладатель ООО «Объединенная Компания РУСАЛ Инженерно-технологический центр». № 2012158363, заявл. 29.12.2012, опубл. 27.05.2014.