System and method for purifying vanadium pentoxide

A system for purifying vanadium pentoxide, comprising a feeding device, a low temperature chlorination fluidized bed, a rectification and purification device, a plasma oxidation device, a tail gas washing absorber, an induced draft fan and a chimney;

• wherein the feeding device comprises an industrial grade vanadium pentoxide hopper, an industrial grade vanadium pentoxide screw feeder, a carbon powder hopper and a carbon powder screw feeder;
• the low temperature chlorination fluidized bed comprises a chlorination bed feeder, a chlorination fluidized bed body, a chlorination bed cyclone separator, a flue gas heat exchanger, a flue gas condenser, a chlorination bed acid-seal tank and a chlorination bed spiral slag-discharging device;
• the rectification and purification device comprises a distilling still, a rectifying column, a distillate condenser, a reflux liquid collecting tank, a silicon-containing vanadium oxytrichloride storage tank, a rectification section acid-seal tank, a high-purity vanadium oxytrichloride condenser, and a high-purity vanadium oxytrichloride storage tank;
• the plasma oxidation device comprises an air filtration purifier, a reactant nozzle, a plasma reactor, a primary cyclone separator, a secondary cyclone separator, a rotary-vane pump and a gas compressor;
• wherein a feed outlet at the bottom of the industrial grade vanadium pentoxide hopper is connected with a feed inlet of the industrial grade vanadium pentoxide screw feeder;
• a feed outlet at the bottom of the carbon powder hopper is connected with a feed inlet of the carbon powder screw feeder;
• and a feed outlet of the industrial grade vanadium pentoxide screw feeder and a feed outlet of the carbon powder screw feeder are both connected with a feed inlet of the chlorination bed feeder through a pipeline;
• a feed discharge opening of the chlorination bed feeder is connected with a feed inlet at the upper part of the chlorination fluidized bed body through a pipeline;
• a gas inlet at the bottom of the chlorination bed feeder is connected with a nitrogen gas source main pipe through a pipeline;
• the chlorination bed cyclone separator is provided at the center of the top of the expansion section of the chlorination fluidized bed body;
• a gas outlet at the top of the chlorination bed cyclone separator is connected with a hot flue gas inlet of the flue gas heat exchanger through a pipeline;
• a cold flue gas outlet of the flue gas heat exchanger is connected with a gas inlet of the flue gas condenser through a pipeline;
• a gas outlet of the flue gas condenser is connected with a gas inlet of the chlorination bed acid-seal tank through a pipeline;
• a gas outlet of the chlorination bed acid-seal tank is connected with a gas inlet of the tail gas washing absorber through a pipeline;
• a slag-discharge opening at the lower part of the chlorination fluidized bed body is connected with a feed inlet of the chlorination bed spiral slag-discharging device through a pipeline;
• a gas inlet at the bottom of the chlorination fluidized bed body is connected with a hot gas outlet of the flue gas heat exchanger through a pipeline;
• and a cold gas inlet of the flue gas heat exchanger is connected with a chlorine gas source main pipe, the nitrogen gas source main pipe and a compressed air main pipe through pipelines, respectively;
• a liquid outlet at the bottom of the flue gas condenser is connected with a feed inlet of the rectifying column through a pipeline;
• a steam outlet of the distilling still is connected with a steam inlet of the rectifying column through a pipeline;
• a reflux inlet of the distilling still is connected with a liquid reflux outlet at the bottom of the rectifying column through a pipeline;
• a gas outlet at the top of the rectifying column is connected with a gas inlet of the distillate condenser through a pipeline;
• a liquid outlet of the distillate condenser is connected with a liquid inlet of the reflux liquid collecting tank through a pipeline;
• a reflux liquid outlet of the reflux liquid collecting tank is connected with a reflux liquid inlet at the top of the rectifying column through a pipeline;
• a feed discharge opening of the reflux liquid collecting tank is connected with an inlet of the silicon-containing vanadium oxytrichloride storage tank through a pipeline;
• an exhaust gas outlet of the silicon-containing vanadium oxytrichloride storage tank is connected with a gas inlet of the rectification section acid-seal tank through a pipeline;
• a gas outlet of the rectification section acid-seal tank is connected with a gas inlet of the tail gas washing absorber through a pipeline;
• a rectificate outlet of the rectifying column is connected with a gas inlet of the high-purity vanadium oxytrichloride condenser through a pipeline;
• a liquid outlet of the high-purity vanadium oxytrichloride condenser is connected with a liquid inlet of the high-purity vanadium oxytrichloride storage tank through a pipeline;
• and an underflow outlet is provided at the bottom of the distilling still;
• a gas inlet of the air filtration purifier is connected with the compressed air main pipe through a pipeline;
• a gas outlet of the air filtration purifier is connected with an air inlet of the reactant nozzle and a gas inlet of the secondary cyclone separator through pipelines, respectively;
• a liquid outlet of the high-purity vanadium oxytrichloride storage tank is connected with a chloride inlet of the reactant nozzle through a pipeline;
• the reactant nozzle is provided at the center of the upper part of the plasma reactor;
• a feed outlet at the bottom of the plasma reactor is connected with a gas inlet of the primary cyclone separator through a pipeline;
• a gas outlet of the primary cyclone separator is connected with a gas inlet of the rotary-vane pump through a pipeline;
• a gas outlet of the rotary-vane pump is connected with a gas inlet of the gas compressor through a pipeline;
• a gas outlet of the gas compressor is connected with a cold gas inlet of the flue gas heat exchanger through a pipeline;
• a feed discharge opening at the lower part of the primary cyclone separator is connected with a gas inlet of the secondary cyclone separator through a pipeline;
• a gas outlet at the top of the secondary cyclone separator is connected with a gas inlet of the tail gas washing absorber through a pipeline;
• and a feed outlet at the bottom of the secondary cyclone separator is connected with a high-purity vanadium pentoxide product hopper through a pipeline;
• a gas outlet of the tail gas washing absorber is connected with a gas inlet of the induced draft fan through a pipeline;
• and a gas outlet of the induced draft fan is connected with a gas inlet at the bottom of the chimney through a pipeline.