Large-scale continuous attrition grinding of coarse kaolin.
Davis-EG; Collins-EW; Feld-IL
Tuscaloosa, AL: U.S. Department of the Interior, Bureau of Mines, RI 7771, 1973 Aug; :1-22
Large-scale ultrafine grinding tests of a coarse kaolin were made using the Bureau of Mines-developed attrition grinding process in continuous open- and closed-circuit systems. A 20-inch-diameter attrition grinder, designed and constructed at the Tuscaloosa Laboratory, was used. Studies included single- and multiple-stage open-circuit grinding, and also continuous grinding tests in closed-circuit with a 6-inch-diameter solid bowl centrifuge. Clay feed, containing 9.0 percent minus-2 micrometer ESD, was used at rates up to 840 pounds per hour. Multistage grinding tests gave better results than single-stage treatment when equivalent clay feed rates were used. Closed-circuit grinding tests yielded ground products containing slightly more minus-2-micrometer-ESD clay than the open-circuit grinding when using the same clay feed. Energy consumption was lower in closed-circuit grinding than in batch or open-circuit grinding. A modified two-stage closed-circuit grinding system gave the best grade of product and amount of minus-2-micrometer-ESD clay produced per pound of clay feed. The ground product from this test contained 88.5 percent minus-2-micrometer-ESD material and electrical energy consumption was 327 kilowatt-hours per ton of minus-2-micrometer-ESD material produced. Work done in cooperation with the University of Alabama.
IH; Report of Investigations
NTIS Accession No.
Tuscaloosa, AL: U.S. Department of the Interior, Bureau of Mines, RI 7771
University of Alabama