Abstract
Bentonites vary in their ability to absorb water. The plate water absorbance (PWA) test measures the amount of water that a bentonite can absorb. Plant operators disagree on whether or not the PWA value is a good predictor of how a bentonite will perform as a binder. In this study, experiments were conducted to determine the relationship between the bentonite PWA value and the dry compressive strengths of iron ore pellets. Pellet strength correlated poorly with the standard PWA test results, where bentonites are allowed to absorb distilled water for 18 hours. Correlations improved, but remained marginal, when PWA was measured in water having high concentrations of cations, representative of the water that remains in the iron ore during pelletization.
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References
ASTM E382-97, 1998, “Standard test method for determination of the crushing strength of iron ore pellets,” 1996 Book of ASTM Standards, Vol. 3.06, pp. 57–58 (Metals Test Methods and Analytical Procedures).
ASTM E946-92, 1996, “Standard test method for water absorption of bentonite by the porous plate method,” Annual Book of ASTM Standards, Vol. 3.06, pp. 276–277 (Metals Test Methods and Analytical Procedures).
Bleifuss, R.L., 1999, “Bentonite Survey, Iron Ore Cooperative Research Committee Report,” Coleraine Minerals Research Laboratory, Natural Resources Research Institute, Project#5697116 October 20, 49 pp.
CCI-CMSC, 1994, “Empire Laboratory Green Ball Tests Evaluating the Effect of Wash Water On Bentonite Performance with Viceroy Concentrate,” Cleveland-Cliffs Inc. (CCI) — Cliffs Mining Services Company (CMSC), Memorandum No. 5453, March 31, 10 pp.
Dixon, W.J., and Massey, F.J., 1983, Introduction to Statistical Analysis, 4th ed., McGraw-Hill, New York, NY, pp. 83–84 and Table A5.
Elzea, J., and Murray, H.H., 1994, “Bentonite,” Industrial Minerals and Rocks, D.D. Carr, ed., Society for Mining, Metallurgy, and Exploration, pp. 223–246.
Engesser, J., 2000a, “The Effect of Water Chemistry on Pre-fired Pellet Quality,” Presentation at Michigan Technological University, January 30.
Engesser, J., 2000b, “Bentonite Quality — The Effect of Water Chemistry and Antifreeze Agents on Bentonite Binder Characteristics,” Coleraine Minerals Research Laboratory, Project #5600108, October 17.
Fuerstenau, D.W., and Clark, S.W., 1981, “Interpretation of the role of montmorillonite in the pelletizing of iron ore concentrates,” Preprints of the Third International Symposium on Agglomeration, Numberg, May 6–8.
Grim, R.E., 1968, Clay Mineralogy, 2nd ed., McGraw-Hill, New York, p. 79.
Iwasaki, I., 1999, Personal communication (Senior Research Associate, University of Minnesota, Coleraine Minerals Research Lab)
Railey, R., 2001, Personal communication, (Chemical Engineer, CMSC Research Lab).
Reisch, Franz J., 2000, Personal communication (Manager of Minerals Devel-opment. American Colloid Co.).
Rice, D.A. and Stone, R.L., 1972, “Influence of plant water chemistry on the strength of unfired pellets,” SME/AIME Trans., Vol. 252, March, pp. 1–6
Ripke, S.J. and Kawatra, S.K., 2002, “Effect of cations on magnetite pellet strength,” Minerals & Metallurgical Proc, Accepted for publication, 6 pp.
Ripke, S.J., and Kawatra, S.K., 2000a, “Can fly-ash extend bentonite binder for iron ore agglomeration?” International Journal of Mineral Processing, Elsevier Press, December, Vol. 60, pp. 181–198.
Ripke, S.J. and Kawatra, S.K., 2000b, “Iron ore pellet binding mechanisms pozzolanic vs. physical binders,” Proceedings of the XXI International Mineral Processing Congress, Rome, Italy, July 23–27, Elsevier Press, pp. A4 120–127.
Ripke, S.J. and Kawatra, S.K., 2000c, “Fibrous bonding mechanisms for reducing bentonite dosage,” American Foundry Society Transactions, Vol. 108, pp. 101–104.
Smiernow, G.A., Doheny, E.L., and Kay, J.G., 1980, “Bonding mechanisms in sand aggregates,” AFS Transactions, Proceedings of the 84th Annual Meeting, April 21–25, pp. 659–682.
White, W.A. and Pichler, E., 1959, “Water Sorption Characteristics of Clay Minerals,” Illinois State Geological Survey, Circular, 266 pp.
Wilson, J.M.D., 1980, “The role of Binders in Iron Ore Pelletizing — A Review, Canada Centre for Mineral and Energy Technology,” Mineral Sciences Laboratories Division Report MRP/MSL 80–52 (OP&J), December, 40 pp.
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Nonmeeting paper number 02-315. Discussion of this peer-reviewed and approved paper is invited and must be submitted to SME Publications Dept. prior to Aug. 31, 2003.
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Kawatra, S.K., Ripke, S.J. Studies on the relationship between plate water absorption and unfired iron ore pellet strength. Mining, Metallurgy & Exploration 20, 15–20 (2003). https://doi.org/10.1007/BF03403109
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DOI: https://doi.org/10.1007/BF03403109
Key words
- Iron ore processing
- Taconite pellets
- Bentonite clay
- Plate water absorbance test