Secondary separation of coking coal middlings in spiral separators

Abstract

The results of recovery by secondary separation tests of coking coal middlings are presented. The gravitational separation method, based on the differences in densities among the feed grains in the stream of flowing water, was used in the tests. Coking coal middlings, obtained in the three-product separation process in the coal fines jig of the processing plant of the coking coal mine in the Silesian Voivodeship, were tested. The following spiral separators were used during the separation process: Reichert LD-4 and Krebs 2.85. Based the test results, the most advantageous feed density was determined for each separator. Using the above-mentioned feed density, the concentrate of the lowest ash content and the highest waste output was obtained. The process was repeated for the optimal density to check how the grain classes of the feed separate in the secondary separation products containing coking coal interlayers.