Flotation Studies on Low Grade Magnesite Deposits from Sujikonda near Daroji Bellary district, Karnataka State

Abstract

Magnesite, an important basic refractory raw material, has been in short supply in recent years. To find an alte-rnative to high costlow boron containing sea water magne-site, users have been looking more towards sources of a natural magnesite. Magnesite ( MgCO3 ) is commonly found in granular, compact earthy masses occurring as amorphous or crystalline deposits. The amorphous type of deposits are the most common variety found as veins in serpentine rocks. The low grade ores produced do not meet the chemical purity required by the consuming industries (Table-1). The low grade ores have to be upgraded by physical benefi-ciation methods to render them usable, besides, conserving high grade reserves of magnesite. in view of the proposed Vijayanagara steel plant in Toranagallu, the occurrence of Sujikonda magnesite deposit close to the steel plant attains greater significance. The magnesite deposit of Sujikonda area is of low grade with MgO = 29:60 wt.% ; Ca0 = 5.61 wt. %; Si02 = 3.84 wt. %; and R2 03 = 31.04 wt. %. In the present investigation the authors carried out experiments to understand the flotation behaviour of low grade magnesite.