Studies on thermal beneficiation of low grade rock phosphate

Rock phosphate sample of Rajasthan containing 17.49% P2O5 has been tested for enrichment of P2O5 content by calcination followed by desliming. Process parameters like calcination temperature, calcination time and particle size of rock phosphate for enrichment of P2O5 content are optimised and reported in this paper. Maximum enrichment of 37.2% P2O5 content has been accomplished in the concentrate on calcining -12.5 mm size of rock phosphate at 950°C for 120 minutes resulting 82% recovery of P2O5 and 38% yield of sand.