Non Strategic Value Addition
The first non-strategic value addition activities of IREL in tonnage quantities was concerned with production of composite rare earth chloride, oxide and fluoride to start and later separation of 99.9% pure oxide of individual rare earths like Ce, La, Nd and Pr by multi-stage solvent extraction and fractional precipitation techniques. Oxides of these metal in higher purities are also prepared by RED in kilo gramme quantities using ion exchange technology.
Besides chemical processing of monazite both zircon and ilmenite were found worth value addition from commercial angle.
A dry grindin mill working on the principal of self attrition was commissioned by Chavara in the year 1970 to grind the as separation zircon sand to about 4.5m size(called zirflour) for its application in the ceramic industries. Much later a wet mill with silica as grinding media was commissioned at Chavara to introduced yet another value added material called micro-zir having mesh size in the range of 1 to 3 mm finding specialized application as opacifier. In addition to such physical value addition, the MK unit had set up a small chemical plant to produce zircon frit, zirconium chloride etc. The plant, however, is limited in size and meant primarily for making supply of zircon firt to Nuclear Fuel Complex, Hydrabad. In yet another effort on value addition to zircon, a pilot plant(capacity-3.5 TPA) was set up OSCOM to produce a whole range of zirconia stabilized with CaO, MgO and rare earths.
The most talked about value addition activity of IREL is setting up of a Chemical plant at OSCOM consisting of a Synthetic Rutile Production unit an Acid Regeneration Unit. The SR ficility is equipped with two roasters, two calciners, sixteen digestors for carrying out reduction of ilmenite, leaching of reduced ilmenite with concentrated hydrocloric acid. The leached liquor is treated in the AR unit to regenerate 20% grade HCl for its recycle and reject iron as fine iron oxide powder. The SR unit was stopped in 1997 as it was not financially viable. The company now intends to use the roasters and calciners for the production of partially value added materials like reduced and metallized ilmenite.