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• Coal refuse from the heavy media vessels is carried by a reject screw to <br />dewatering screens which remove excess surface moisture. The dewatered <br />coarse refuse is then transferred to the reject belt which carries the <br />intermediate coal refuse to a storage hopper adjacent to the preparation <br />plant. <br />The fine fraction resulting from initial screening is transferred to a <br />distribution box which splits the flow into three separate streams which <br />feed six (6) Diester tables. The tables achieve a separation between coal <br />and reject materials through differences in specific gravity and <br />differential settling velocities. From the Diester tables fine coal is <br />transferred by a clean coal screw to the clean coal product belt. <br />As raw coal is processed through both the coarse and fine coal circuits <br />very fine coal particles (-28 mesh) mix with and are suspended in the <br />process water. In order to recover this additional coal fraction, process <br />• water is pumped to a process water sump where coal particles are allowed <br />to settle and clarified overflow is decanted from the top of the sump. <br />The resulting slurry of fine coal particles in water then goes to <br />thickening cyclones where additional water and refuse are removed, with <br />the thickened fine coal product moving to fine screens which separate the <br />28 to 80 mesh coal. The 28 to 80 mesh coal then goes to a fine coal <br />centrifuge and dewatered fine coal product is transferred to the clean <br />coal product belt. <br />The -80 mesh coal and the reject product from the cyclones is pumped as <br />a slurry to a clarifier where the coal and rejects settle out and <br />clarified process water is decanted. The thickened fine reject slurry is <br />then pumped from the bottom of the clarifier to a belt press which removes <br />excess moisture. The fine refuse cake drops from the belt press to the <br />reject belt which carries it to a storage hopper adjacent to the <br />preparation plant. - <br />~J <br />2.05.3-24 <br />