The Mineral Beneficiation Group is engaged in R & D in beneficiation of low grade ores and minerals. It has developed expertise and facilities towards carrying out studies on development of process flow-sheets for beneficiation of low and lean grade ferrous, non-ferrous, non-metallic, industrial, refractory, strategic, fertilizer minerals, precious metals, coals and mine/industrial wastes. The laboratory /bench scale beneficiation facilities ranges from size reduction (crushing and grinding), classification, gravity (conventional and enhanced gravity), magnetic (high and low intensity/ dry and wet type), electrostatic separation, froth flotation, column flotation and dewatering (thickening/ filtration) units. Similarly, the pilot scale beneficiation facilities consist of state-of-art equipment with treatment capacity of 0.5 to 5 tph. The plant is divided into different sections, viz. Crushing and Screening; Scrubbing, Washing & Classification; Grinding; Gravity concentration comprising Tabling, Spiraling Jigging, Magnetics Separation, Flotation; De-watering comprising thickening, filtration and drying.
Mineral Beneficiation Group has focused on development of process flowsheet for ferrous, non-ferrous ores, industrial and strategic minerals, coals and mine/industrial wastes. During the past six decades, over 900 R & D studies have been successfully completed after systematic research on beneficiation of a large variety of indigenous and foreign ore and mineral samples. Based on the studies carried out a large number of commercial beneficiation plants have been commissioned and the Group is continued to gives support to mineral based industries.
The presently the Mineral Beneficiation Group is focusing on the following areas:
i) Mathematical modeling and simulation
Simulation studies will be useful in predicting the optimum operating conditions of the circuit and therefore retrofitting the circuit. The process of developing a model for crushing circuit and simulating it regularly will optimize the parameters affecting the circuit performance.
ii) Dry beneficiation
CSIR-NML has developed expertise and facility for dry beneficiation of non-coking coal. Process flow sheet was developed for reducing ash in non-coking coal for application in thermal power plant and DRI based on the
studies carried-out at CSIR-NML. With this expertise developed, CSIR-NML is working on development of technology for dry beneficiation of Indian high ash non-coking coal from different coalfields in collaboration with coal industries.
iii) Processing of Mine/industrial wastes
The management of tailings from iron ore mines is an important issue not only from the point of view of pollution control but also of the conservation of resources. As per the guidelines of IBM the iron content in the tailing should be below 45%. In view of the above, CSIR-NML had undertaken study on characterization and beneficiation study of iron ore slime from eastern part of India and developed process technology for recovering of iron values from slimes.
iv) Beneficiation of strategic minerals
MNP division of CSIR-NML is working in physical beneficiation of strategic minerals like tungsten. A project on extracting tungsten values from gold tailings is being carried at CSIR-NML presently.