Influence of the Physical Properties of Liquids and Diameter of Bubble on the Formation of Liquid Column at the Interfac
- PDF / 1,428,021 Bytes
- 9 Pages / 593.972 x 792 pts Page_size
- 103 Downloads / 253 Views
INTRODUCTION
INCREASING the reactivity between the metal and slag in a refining process of steel-making is desired. The formation of metal or slag particles, respectively, in slag or metal phase at the agitated interface of molten metal and slag phases in steel-making processes has been reported.[1–4] The formation of metal emulsion in the slag phase would increase the reaction rate between the metal and slag. When a gas passes through the interface, gas bubbles covered by the lower liquid film are formed at the interface. It has been reported that small particles are formed and entrapped in the upper layer by the rupture of this thin film at the interface.[2,3] Alternatively, it has been observed that the bubbles leave the interface covered with the film of the lower liquid, and a metal
MASANORI TANNO is with JFE steel, Okayama 7128511, Japan. JIANG LIU is with the Laboratory for Advanced Nuclear Energy, Tokyo Institute of Technology, Tokyo 1528550, Japan. XU GAO, SHIGERU UEDA, and SHIN-YA KITAMURA are with the Institute of Multidisciplinary Research of Advanced Materials, Tohoku University, Sendai 9808557, Japan. Contact e-mail: tie@ tohoku.ac.jp SUN-JOONG KIM is with the Department of Materials Science & Engineering, Chosun University, Gwanju 61452, Korea. Manuscript submitted June 14, 2017.
METALLURGICAL AND MATERIALS TRANSACTIONS B
column is formed through falling the film of lower liquid from the bubble, or through the lower liquid following the bubble in the upper layer; subsequently, droplets are formed from the column.[4] The formation of the column is related to the rupture of the film of the lower liquid. The rupture phenomenon of thin films formed on the surface of spheres such as bubbles has been researched as the film drainage problem.[5,6] It was demonstrated that the rupture of the liquid film is influenced by the interfacial tension, specific gravity of liquid, and wetting angle; further, the shape of the liquid column varies depending on the interface energy, particle size of the bubble, and specific gravity of the lower layer.[7,8] Many experiments have been performed to investigate the relationship between these phenomena and physical properties at room temperature by using mercury–water, mercury–oil, water–cyclohexane, and glycerol water–cyclohexane systems. However, the physical properties of the system employed in these experiments were different from those of the melt formed in the smelting process such as metal–slag and matt–slag systems. Compared with the actual system, the specific gravity of the aqueous solution–oil system is low. An in situ observation of emulsion formed in the metal–salt system was conducted by Song et al.,[9] wherein the physical properties of the system were similar to those of the metal–slag systems. Yoshida et al. determined that when the bubbles pass through the interface in this
system, both behaviors of liquid film rupture at the interface and in the upper layer after bubble rising occur simultaneously.[10] The former generates a tiny droplet of metal, and the latter for
Data Loading...