Influence of impeller shape on the gas bubbles dispersion in aluminium refining process

• Autorzy: Saternus M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The most popular method of aluminium refining is blowing of refining gas through the liquid metal. The way the refining gas is introduced to the liquid metal significantly influences the time and course of degassing process. Rotary impellers seem to be the best solution, especially taking into account reaching good level of gas dispersion in the liquid aluminium. However, the construction of impellers also influences the obtained gas dispersion in liquid metal, especially considering the processing parameters such as flow rate of refining gas and rotary impeller speed. Design/methodology/approach: To observe the phenomena occurring during the aluminium refining process physical modelling was applied. Test stand for such modelling was built at 1:1 scale with the transparent tank to observe the level of gas dispersion in the liquid. The built model has to fulfill the rules coming from the theory of similarity. Findings: The choice of optimal parameters is very important to the particular type of impeller. As a result of research the processing parameters were chosen to the appropriate type of gas dispersion. The most desirable type of dispersion is an uniform dispersion. According to the research the best impeller seems to be impeller No 1. Research limitations/implications: There are differences between results coming from modelling research and industrial test. So, the further research should be conducted with a chosen impeller in industrial conditions. Practical implications: From industrial point of view it is important to test the impeller construction and their geometry in laboratory before industrial test. It gives some ideas how the particular impeller will behave in industry. To control the process of aluminium refining and conducting it optimally it is really important to know its mechanism better. Originality/value: This paper presents original modelling research of aluminium refining process conducted in URO-200 reactor.

Słowa kluczowe

EN

metallic alloys; aluminium; physical modelling

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2012
• Tom: Vol. 55, nr 2
• Strony: 285--290
• Opis fizyczny: Bibliogr. 26 poz., rys., tab.

Twórcy

autor

Saternus M.

• Metallurgy Department, Silesian University of Technology, Faculty of Materials Engineering and Metallurgy, ul. Krasińskiego 8, 40-019 Katowice, Poland

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