ANODE GAS DYNAMICS IN HIGH-TEMPERATURE CRYOLITE MELT-ALUMINA SLURRY
https://doi.org/10.17073/0021-3438-2017-1-13-18
Abstract
The paper shows the results of simulating physical behavior of bubbles formed by oxygen electrowinning on an inert anode during hightemperature alumina slurry electrolysis in a fluoride melt. As part of the study, similarity criteria were calculated with experiments conducted on a water-based model of a cell with vertical electrodes, and the data on bubble behavior in slurry was obtained by video recording. The 20 % aqueous sulfuric acid solution with 30 vol.% alumina content was used as electrolyte for the model. Experiments were conducted in the electric current density range from 0,05 to 0,25 A/cm2. The video was recorded using the Nikon D3100 camera with 30 frames per second rate. The motion pattern of bubbles was obtained along with the quantitative data describing coalescence and bubble rise velocity. 125 bubbles with a thickness of 0,8 to 2,3 mm were analyzed to determine the average bubble rise velocity. Bubbles rose in a slug regime at 1,0–2,3 cm/s. The thickness of a bubble layer was about 5 mm. Further studies will be conducted to obtain new data on the bubble behavior at different solid contents, current densities, electrodes inclination angles, and particle size distributions.
About the Authors
A. S. Yasinsky
Siberian Federal University
Russian Federation
Russian Federation
postgraduate student at Department of non-ferrous metals,
660025, Krasnoyarsk, Krasnoyarskii rabochii, 95
P. V. Polyakov
Siberian Federal University
Russian Federation
Russian Federation
Dr. Sci. (Chem.), prof., professor-consultant at Department of non-ferrous metals,
660025, Krasnoyarsk, Krasnoyarskii rabochii, 95
A. B. Klyuchantsev
Siberian Federal University
Russian Federation
Russian Federation
senior researcher at Department of non-ferrous metals
660025, Krasnoyarsk, Krasnoyarskii rabochii, 95
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Review
For citations:
Yasinsky A.S., Polyakov P.V., Klyuchantsev A.B. ANODE GAS DYNAMICS IN HIGH-TEMPERATURE CRYOLITE MELT-ALUMINA SLURRY. Izvestiya. Non-Ferrous Metallurgy. 2017;(1):13-18. (In Russ.) https://doi.org/10.17073/0021-3438-2017-1-13-18
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