Alumina: Calcination Control and Smelting Use
Specific surface area should be used as the standard method for qualifying the degree of calcination of smelter-grade alumina. It is a property which is sensitive to temperature change in the calciner. The analytical method is precise, rapid, and operator-insensitive. It is thus a practical method for use in calciner control. Furthermore, for the smelter operator it is a direct measure of the performance of the alumina in a dry-scrubbing system.
It is, however, a one number average property. Aluminas can vary in the spread of the degree of calcination and this can have significant effects on its behavior in use. Smelter operators should be aware of this fact and attempt to determine if the alumina is as uniform as they expect.
KeywordsCalcination International Standard Organization Calcination Process Rotary Kiln Refractive Index Distribution
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- 1.L.N. Less, “The Crusting Behavior of Smelter Aluminas,” in Light Metals 1976, edited by S. R. Leavitt, The Metallurgical Society of AIME, Warrendale, Pennsylvania, 1982, pp. 315–331.Google Scholar
- 2.W.D. Lamb, and J.W.J. Burck, “Dry Scrubbing of Aluminum Cell Gases: An Index for System Performance,” in Light Metals 1982, edited by J.E. Anderson, The Metallurgical Society of AIME, Warrendale, Pennsylvania, 1982, pp. 1089–1104.Google Scholar
- 3.Benny E. Raahange, Paul H. Hansen, Kirsten Theisen, and Joachim Nickelsen, “Application of Gas Suspension Calciner in Relation to Bayer Hydrate Properties,” in Light Metals 1981, edited by Gordon M. Bell, The Metallurgical Society of AIME, Warrendale, Pennsylvania, 1981, pp. 229–249.Google Scholar
- 4.L. Reh, “The Lurgi-VAW Circulating Fluid-Bed Process for Calcining Aluminum Trihydrate,” Tecno-Germa, 1975, Peking sep. 5–18.Google Scholar
- 5.International Organization for Standardization.Google Scholar
- 7.W.D. Lamb, “A Study of the Equilibrium Adsorption of Hydrogen Fluoride on Smelter-Grade Aluminas,” in Light Metals 1978, edited by John J. Miller, The Metal-lurgical Society of AIME, New York, pp. 425–444.Google Scholar
- 8.J.W. Colpitts, “Evaluation of Aluminas for the Alcoa 398 Process,” in Environmental Control, edited by Carl Rampacek, The Metallurgical Society of AIME, 1972, pp. 259–278.Google Scholar
- 9.W. Muhlrad, and A. Chauvineau, “Pechiney/Prat Daniel Process for Control of Fluorine Compounds Released by Aluminum Reduction Pots,” in Light Metals 1973, edited by A. V. Clack, The Metallurgical Society of AIME, 1973, pp. 209–222.Google Scholar
- 10.R. DeMarco, and M. Baverez, “A Study of the Adsorption of Hydrogen Fluoride on Certain Smelter Grade Aluminas,” in Light Metals 1979, edited by Warren S. Peterson, The Metallurgical Society of AIME, Warrendale, Pennsylvania, 1979, pp. 909–926.Google Scholar
- 11.A.R. Johnson, “Alumina Crusting and Dissolution in Molten Electrolyte,” in Light Metals 1981, edited by Gordon M. Bell, The Metallurgical Society of AIME, Warrendale, Pennsylvania, 1981, pp. 373–387.Google Scholar