Combined magnetic, electrostatic, and gravity separation techniques for recovering strategic heavy minerals from beach sands

A combination of unit operations like gravity, magnetic, and electrostatic separation techniques were applied to separate strategic heavy minerals from bulk samples taken from two coastal stretches of Kappil-Varkala (KV) and Shanghumugham-Kovalam (SK) in Thiruvananthapuram, south Kerala, India. On processing the feed, the concentrate obtained contains 67.3% THM for KV and 65.15% THM for SK, out of which ilmenite predominantly exists with a yield of 45.55 and 43.6% in weight followed by other minerals like sillimanite, monazite, zircon, rutile, leucoxene, and garnet. Analysis indicates that judicious combination of unit operations like gravity, magnetic, and electrostatic separation techniques can efficiently recover heavy mineral species even from placers of smaller deposit.