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The +34 inch raw coal goes directly to the <br /> heavy media circuit. This consists of a heavy media vessel, <br /> several rinse screens, and magnetic separator . A suspension of <br /> pulverized magnetite in water fills the vessel . The specific <br /> gravity of the medium is maintained at 1 .35 . When the coal is <br /> fed into the vessel, the clean coal , having a low specific gravity, <br /> floats in the heavy medium and the heavier refuse materials sink <br /> to the bottom. The clean coal overflows the heavy media vessel <br /> and is rinsed and d.ewatered on screens and conveyed directly to <br /> the clean coal bins . A chain conveyor scrapes the refuse out of <br /> the bottom of the vessel onto a rinse screen from whence it is <br /> transferred to the refuse belt . Rinse water from the screens is <br /> passed over a magnetic separator where the magnetite is reclaimed <br /> and returned to the heavy medium suspension. <br /> All -34 inch raw coal material enters a sump <br /> and is pumped as a slurry to a distributor ahead of the deister <br /> tables (second circuit) . A deister table is a large nearly flat <br /> table that oscillates . Ridges run diagonally across the table. <br /> Because of the shaking action of the table, the materials strati- <br /> fy in the water medium with the lighter clean coal on top. The <br /> coal is washed over the ridges to the side of the table and the <br /> heavier refuse follows the ridges to the end of the table. The <br /> refuse material is dewatered and conveyed to the refuse pile. <br /> The clean coal overflows the side of the tables opposite the feed <br /> well . It is then passed over 11 millimeter sieve bends . The +28 <br /> mesh clean coal proceeds directly into a centrifugal dryer . <br /> After mechanized drying the +28 mesh clean coal is conveyed to <br /> the thermal dryer for final evaporation of excess surface moisture. <br /> �D <br />