TECHNOLOGY FOR TITANIUM SPONGE PRODUCTION


DRDO has developed a state-of-the art technology for the production of titanium sponge, which is the principal raw material for the manufacture of Ti alloys for aerospace and various corrosion resistance applications. Titanium sponge is mainly produced by high temperature magnesio-thermic reduction of titanium tetrachloride, which is prepared by carbo-chlorination of mineral concentrates. Currently, the sponge production is being practiced commercially by only a select group of four or five countries in the world.


 The indigenous technology development program involved design and development of various systems and equipment, study and fine tuning of important process parameters, and technology demonstration with adequate consistency and reproducibility of sponge quality involving the following activities of sponge production:


  • Purification of raw titanium tetrachloride (TiCl4) in two packed beds distillation columns for removing dissolved gases, low and high boiling impurities, chlorides to prepare ‘metal grade’ tetrachloride continuously at the rate of 150 kg/h.


  • Reduction of pure TiCl4 by magnesium metal followed by vacuum separation of titanium sponge to remove entrapped Mg/MgCl2 employing a twin reactor assembly made of stainless steel, and an electrical resistance furnace to produce the metal in a batch size of about 3000 kg of sponge.


  • Process automation and data logging using a Distributed Control System.


  • Ejection of titanium sponge cake from the reactor followed by a series of mechanical processing operations for careful gradation and size reduction to prepare homogenous sponge lots suitable for ingot melting.

    The technology gap hitherto prevailing in the titanium metal production has been bridged. It would pave the way for setting up of the first commercial plant for titanium sponge production in the country to gainfully exploit the vast titanium mineral reserves.