Electrolyte viscosity and solid phase formation during aluminium electrolysis

Архипов, П. А.; Катаев, А. А.; Руденко, А. В.; Zaykov, Yury

doi:10.1016/j.elecom.2020.106893

Cited by 9 publications

(3 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Aluminum metallurgy refers to the production of refining Al products by smelting, electrolysis, casting, or melting of bauxite or waste Al [ 29 , 30 ]. It includes alumina, electrolytic Al, and secondary Al metallurgy, with alumina production primarily following the Bayer method.…”

Section: Resultsmentioning

confidence: 99%

Characteristics of solid waste from common generation source in nonferrous smelting industry reveal a new classification method

Li,

Yang,

Die

et al. 2023

Heliyon

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 99%

Characteristics of solid waste from common generation source in nonferrous smelting industry reveal a new classification method

Li,

Yang,

Die

et al. 2023

Heliyon

View full text Add to dashboard Cite

“…The activation energy of viscosity for some oxide-fluoride cryolite melts is given in Table 2 . It was calculated using the equation for the viscosity proposed in our papers [ 30 , 31 ]: η = 71.75 − 1.33·10 −1 ·(T − 273) − 8.21·10 −3 ·C (Al 2 O 3 ) + 3.33·10 −1 ·CR + 0.0796·C (CaF 2 ) −0.625·10 −5 ·T 2 − 2.08·((C (CaF 2 )+ C (Al 2 O 3 ))/C (Al 2 O 3 ) 1.5 + 8.12·10 −5 ·C (Al 2 O 3 ) 3 where T is the temperature (K), C (Al 2 O 3 ), and C (CaF 2 ) are the concentrations of components (wt%), the CR is the cryolite ratio. The equation is true in the temperature range from the liquidus to 1300 K, CR ranges from 2.1 to 2.5, the Al 2 O 3 and CaF 2 content is up to 6 and 8 wt%, respectively.…”

Section: Resultsmentioning

confidence: 99%

The Electrical Conductivity of Molten Oxide-Fluoride Cryolite Mixtures

Архипов¹

2021

Materials

Self Cite

View full text Add to dashboard Cite

A new way to reduce the energy consumption during the operation of powerful aluminum reduction cells is suggested via reducing the resistance of the electrolyte, i.e., increasing its electrical conductivity. The electrical conductivity of molten cryolite mixtures NaF-AlF3-CaF2-Al2O3 with cryolite ratio (CR) of 2.1–3.0 and content of CaF2 and Al2O3, up to 8 wt%, was measured at the temperatures from liquidus to 1300 K. Based on the experimental results, a multifunctional equation for the electrical conductivity of oxide-fluoride cryolite melts was evaluated. The experimental and calculated values of the electrical conductivity agree within 1.5%. The activation energy of the electrical conductivity of the NaF-AlF3-CaF2-Al2O3 melts was estimated. The activation energy of electrical conductivity for molten NaF-AlF3 mixtures with CR 3.0 and 2.1, determined by the most mobile cations Na+, increased from 15.8 kJ/mol up to 18.5 kJ/mol. It was found that CR had a greater impact on the activation energy than the changes in the Al2O3 or CaF2 concentrations. Based on the ratio of the activation energies of the electrical conductivity and the viscous flow, the correlation between the electrical conductivity and viscosity of molten cryolite mixtures NaF-AlF3-CaF2-Al2O3 was illustrated.

show abstract

“…По данным разных авторов, величина вязкости криолитоглиноземных электролитов промышленного состава NaF-AlF 3 -CaF 2 -Al 2 O 3 с криолитовым отношением КО = 1,8÷2,6 в интервале температур t = 945÷970 °С изменяется от 1 до 5 мПа•с [11,[18][19][20][21][22][23]. В работе [11] проведен сравнительный анализ имеющихся в литературе экспериментальных данных по вязкости расплавленного криолита Na 3 AlF 6 (КО = 3) и термодинамических расчетов, выполненных авторами.…”

Section: Introductionunclassified

Viscosity of conventional cryolite-alumina melts

Руденко

Катаев

Zaykov

et al. 2021

Izv.VUZ. Tsvet. Met.

View full text Add to dashboard Cite

The study covers the viscosity of NaF–AlF3–CaF2–Al2O3 conventional cryolite-alumina melts with a cryolite ratio CR = 2.3 depending on the CaF2, Al2O3 content and temperature. The viscosity of cryolite-alumina electrolyte samples prepared under laboratory conditions and electrolyte samples of industrial electrolytic cells was measured by the rotary method using the FRS 1600 rheometer («Anton Paar», Austria). The laminar flow region of the melt determined according to the dependence of viscosity on shear rate at a constant temperature was 10–15 s–1 for all the studied samples. The temperature dependence of cryolite-alumina melt viscosity was measured at a shear rate of 12 ± 1 s–1 in the temperature range from liquidus to 1020 °C. It was shown that the change in the viscosity of all samples in the investigated temperature range (50–80 °С) can be described by a linear equation. The average temperature coefficient of linear equations describing the viscosity of cryolite-alumina electrolytes prepared in laboratory conditions was 0.005 mPа· s/°С, which is 2 times less compared to industrial cell electrolytes. Thus, the change in the viscosity of industrial cell electrolytes with increasing temperature is more significant. Both alumina and calcium fluoride additives increase the cryolite melt viscosity. The viscosity of samples prepared with the conventional composition NaF–AlF3–5%CaF2–4%Al2O3 (CR = 2.3) is equal to 3.11 ± 0.04 mPа· s at an electrolysis operating temperature of 960 °C, while the viscosity of industrial cell electrolytes with the same cryolite ratio is 10–15 % higher and falls in the range of 3.0–3.7 mPа· s depending on the electrolyte composition.

show abstract

Electrolyte viscosity and solid phase formation during aluminium electrolysis

Cited by 9 publications

References 7 publications

Characteristics of solid waste from common generation source in nonferrous smelting industry reveal a new classification method

Characteristics of solid waste from common generation source in nonferrous smelting industry reveal a new classification method

The Electrical Conductivity of Molten Oxide-Fluoride Cryolite Mixtures

Viscosity of conventional cryolite-alumina melts

Contact Info

Product

Resources

About