Method for removing vanadium impurity in titanic chloride by forced assisted-circulation heating

Abstract

The invention provides a method for removing impurity vanadium in titanium tetrachloride by forced external circulation heating, which comprises the following steps: coarse titanium tetrachloride enters an evaporator for vanadium removing reaction from a coarse titanium tetrachloride storage tank, reacts with mineral oil from a mineral oil storage tank to generate low valance vanadium chloride like vanadium oxychloride and the like and carbon, and is transported to a forced circulation heat interchanger through a submerged sludge pump by pressurizing, titanium tetrachloride passes through a tube pass, while heating medium passed through a shell pass; titanium tetrachloride flows at high speed under high pressure in the tube pass, flows out of the heat interchanger, and is sprayed into the evaporator for vanadium removing reaction, afterward, a part of the titanium tetrachloride is gasified and led into a vanadium removing tower, while ferric trichloride in the coarse titanium tetrachloride, low valance vanadium chloride like vanadium oxychloride and the like and carbon generated by reaction remains in the evaporator for vanadium removing reaction in a suspended state. As forced external circulation heating is adopted, titanium tetrachloride flows at high speed under high pressure, which prevents suspended substances from depositing and scarring on the wall of the heating tube, improves the heating efficiency by 20 percent-30 percent, and prolongs the service life of the heat interchanger.

Description

Technical field: [0001] The invention belongs to the production technology of titanium tetrachloride, in particular to a method for removing vanadium impurities in titanium tetrachloride. Background technique: [0002] During the production of titanium tetrachloride, the vanadium oxide in the titanium-rich material undergoes a chlorination reaction to generate vanadium oxytrichloride. Since the boiling point of vanadium trichloride is close to that of titanium tetrachloride, they cannot be effectively separated by simple distillation; only the reduction of vanadium trichloride to low-valent vanadium chloride such as vanadium dichloride with a high melting point , and then evaporated to remove it from titanium tetrachloride. At present, there are two kinds of chemical vanadium removal processes used in China: copper removal of vanadium and mineral oil removal of vanadium. The cost of vanadium removal from copper is high, the yield of titanium tetrachloride is low, the effic...

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Problems solved by technology

[0003] In order to solve the problem that the titanium tetrachloride in the evaporator contains vanadium oxychloride, carbon and ferric chloride suspended matter in the process of removing vanadium from titanium tetrachloride, which will cause scaling or scarring on the heat exchanger coil and affect the heating efficiency. As well as the air pollution problem caused by dismantling the heat exchanger with serious scarring, a method of forcing external circulation heating to remove vanadium impurities in titanium tetrachloride was proposed

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