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       CODE: 511.382-010 Buy the DOT:Download/CD-ROM
TITLE(s): TUNGSTEN REFINER (smelt. & refin.) alternate titles: chemical operator
Controls chemical-processing equipment to recover tungsten oxide from ground concentrated ore:
Starts conveyor to fill reactor tank with ore. Turns valves to pump specified quantity of
hydrochloric acid into tank and to admit steam into tank jacket. Observes temperature gauge and
adjusts valves to maintain acid solution at specified temperature for specified time. Fills tank
with water to wash slurry, and drains waste-bearing water. Turns valve to pour slurry into caustic
tank. Precipitates impurities, such as chlorides and oxides, by adding ammonia and sulfuric acid to
solution. Filters solution into holding tank to remove precipitate. Adds specified amount of
hydrochloric acid to tank to crystallize solution. Dries tungsten oxide crystals by pumping them
through filter or centrifuge.
GOE: 06.02.10 STRENGTH: M GED: R3 M2 L2 SVP: 5 DLU: 77
ONET CROSSWALK: 92935 Chemical Equipment Controllers and Operators
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