Mining & Minerals
Mining of raw beach sand containing the six heavy minerals and separation of the later in adequate purities happen to be the common activity of all the three Mineral Division namely Chavara, MK and OSCOM. As per as mining practice is concerned, they do differ from one division to other. For example at MK, all the raw sand required to operate the plant at its full capacity is collected by the fisherman of surrounding villages from near by beaches and supplied to the unit at a cost. At Chavara also beach washing is available but not in adequate quantity to meet the full requirement of the plant.
The unit therefore adopt wet mining operation involving use of Dredge and Wet Concentrator(DWC) to exploit the inland deposits away from the beaches. For example Chavara operate two DWC s of about 100 t/hr capacities to generate sand feed analyzing about 85% heavy mineral concentration.
The mineral free sand coming out of the concentrator is pumped back to the pond for the operation of DWC. In the case of OSCOM, the entire mining operations involves dredging of the mineral deposits on much larger scale (500 t/hr) augmented by smaller sized (~100) supplementary.
The heavy mineral rich sand feed either in the form of beach washings or dredge concentrate is subjected to final concentration in a facility provided with a host of spirals to enrich the feed with 97-98% heavy minerals. Such upgraded material is next dried in a fluid bed drier to take on the separation of individual minerals/ores by taking advantage of the difference in their electrical, magnetic properties as well as specific gravity.