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A Continuous Dielectric Separator for Mineral Beneficiation.

Jordan CE; Sullivan GV; Davis BE; Weaver CP
MISSING :18 pages
Under its program of advancing minerals technology, the federal Bureau of Mines has invented a laboratory apparatus for continuous separation of minerals based on differences in dielectric properties. The separator consists of a rotating drum electrode and a wire screen electrode positioned 3 mm apart. A high voltage applied across the electrodes that are immersed in a dielectric fluid produces a high-gradient electric field. The high-dielectric- constant (k) minerals are attracted to and conveyed through the separator by the rotating drum electrode, while the low k minerals settle through the screen electrode. Several design and operating parameters, such as electrode configurations, the dielectric liquid and its dielectric constant, electrical voltage and frequencies, feed rates, and particle sizes were studied. In addition, 28 different mineral mixtures were tested with the dielectric separator. In typical tests, a sample of rutile and quartz gangue containing 10-percent rutile was concentrated to 62-percent rutile with 94-percent rutile recovery. A second-stage dielectric separation of the rutile concentrate produced a 92-percent-rutile concentrate. The overall rutile recovery for the two-stage dielectric separation was 86 percent.
Publication Date
Document Type
IH; Report of Investigation;
Fiscal Year
Identifying No.
RI 8437
NIOSH Division
Source Name
Page last reviewed: November 26, 2021
Content source: National Institute for Occupational Safety and Health Education and Information Division