Beneficiation of a High Sillica Limestone(Sample No.CG1)from Yeotmal Dt., Maharashtra

Abstract

A sample of silicious limestone designated CG1 from Yeotmal Dt., Maharashtra was received from the Director of Mines and Geology, Govt. of Maharashtra, for beneficiation studies in National Metallurgical Laboratory so as to make it suitable for cement manufacture. The sample assayed 43, 44% CaO, 17.5% Si02, 1. 45% Mg0, 2.0 Al203 and 34, 14 %CO2. Quartz constituted the principal gangue and grinding the sample to -150 mesh was necessary to produce a cement grade of concentrate from it, Flotation after grinding to 94, 5% -200 mesh and employing sodium silicate and oleic acid emulsion, followed by one cleaning of the rougher float yielded a refloat concentrate assaying 48. 73% CaO and 12. 06% Si02 with a recovery of 82.5 Ca O. This concentrate is of a grade suitable for cement use, Even better grades of limestone concentrates analyzing from 53.2% CaO to 48,93 %CaO, with recoveries ranging from 69. 4% CaO to 88. 0% Ca0 respectively could be produced, depending upon the number of cleanings to which the rougher float is subjected to.