dhana reddy

Iron is the most important of all metals and ~ 98% of it, in the form of iron ore/pellets, is used as the key raw material in making steel, with its per-capita consumption often seen as an Index for a nation's Prosperity. Salient aspects of the industries of iron ore mining and steel-production are presented. These include deposittypes and grades of iron-ore, iron ore minerals with Fe-contents, major producing-exporting-importing countries, international/ national prices of iron ore; and major producing countries of steel, international/national production figures, processes of steelmaking, including recent hydrogen-energy based green steel/iron ore under de-carbonisation. The less available high-grade Fe ore (> 63.5% Fe), as compared to that of the benchmark or standard grade (62% Fe) and low-grade (< 59% Fe) iron ores, has many beneficial features in steel-making, carries a premium price of US $ 1-2/tonne for every 1% increase in Fe-grade over that of the standard grade and, hence, is much sought after. In this communication, two low-cost, potential alternatives to the highgrade Fe ore for steel-making are proposed from the mineral sand industry. These are: (i) placer magnetite-sand, with an example from the coastal Nizampatnam heavy mineral sand deposit in Andhra Pradesh, and (ii) by-product Fe, generated during the beneficiation of ilmenite-sand for high Ti-products such as synthetic rutile/anatase, titanium dioxide pigment, Ti-sponge, Ti-metal etc. A brief account of the mineral sand deposits, including the processes to obtain the above proposed alternatives and the consequent multiple benefits for both the steel and mineral sand industries, is presented in this paper.

Critical minerals (CMs) are metals and non-metals which are vital for the economic well-being of society. However, their supply may be at risk due to geological scarcity, geopolitics, trade policy, vulnerability and other factors. CMs include REEs, PGEs, Li, Be, Ga, Ge, In, W, Co, Nb–Ta, Mo, Sb, V, Ni, Te, Cr, Sn, Th–U, Zr, Hf, Se, Te, Re, phosphate, potash, etc. They occur in three sources, viz. primary – in ore deposits; secondary – in waste, like the electronic (e)-waste, and tertiary – in imports. Currently, many CMs (like REEs, PGMs, Cr, W, Co, Cd, Ge, Se, Te and Re) are recovered primarily during the mineral processing of ores of major commodities, such as Cu, Pb, Zn, Ni and Au. Some CMs like Au, Ag, Pt, Co, Sn and Al are being recovered and reused by recycling the environmentally hazardous, but valuable e-waste that contains ~50 chemical elements. The CMs thus recovered are in much demand in diverse industries based on conventional, high-tech and cutting
edge technologies.
Keywords: Critical minerals, e-waste, industrial uses, ores.

 Abstract: Critical minerals (CMs: mostly metals and a few non-metals) have a global demand due to their important/strategic applications in many high-tech industries such as the green-renewable energy (for decarbonisation to minimise the disastrous effects of climate change), electricals and electronics, telecommunications, superalloys, nuclear, space, artificial intelligence, defence etc. The list of CMs is dynamic and depends upon the availability and perspective of each country, based upon the issues like geological scarcity, geopolitical considerations, trade policy, problems in supply-chain and other factors. CMs can be broadly grouped into: (i) REEs; (ii) Battery Metals (Li, Co, Ni, Mn, Graphite); (iii) Alloy Metals (Ti, V, Cr, Ni, Nb-Ta, Sn); (iv) Nuclear Metals (U, Th, Zr-Hf, Be); (v) Precious Metals (Au, Ag, PGMs); (vi) Toxic Metals (Pb, As) and (vii) Fertiliser Commodities (Phosphate, Potash). Geologically, they are recoverable from diverse materials of rocks, ore minerals, mineral concentrate, sands, etc., with their sources being either primary or secondary. The primary sources for CMs were deposited during period(s) of mineralisation in a wide variety of rock types. When such primary sources of rocks and ore deposits (constitute a provenance) were subjected to alteration, due to weathering or other surficial processes resulting from descending surface waters, gave rise to the secondary sources of CMs like the supergene deposits of laterite, overburden, conglomerate and placers of different types. A brief note on the recovery and extraction of CMs is presented. Indian examples of the primary and secondary geological sources for the CMs, and their recovery and extraction are added.  Keywords: Critical minerals, geo-sources, recovery, processing, Indian examples. 

As the global generation of waste (i) is of the order of &gt; 2 billion tons per year and is expected to reach ~ 3.5 billion tons annually by 2050 and (ii) has a critical bearing on the worldwide problems of pollution control (PC), global warming (GW) and climate change (CC), a government-aided and monitored, and peopleparticipated waste management (WM) is desirable for a hygienic, healthy and sustainable society. Aiming this and targetting for zero-waste, the WM has been undertaken in India ̶ from the collection of waste at source to its minimal, safe and monitored disposal in a landfill, with intermediate stages of transportation, segregation and recycling for value-added products ̶ , under the Swatchh Bharat Ayojan (Clean India Mission) programme. All the above stages of WM have been adopted in various ways in both the urban and rural areas. Based on a yearly evaluation of the WM, some cities and states have been designated as “clean”. An account of the presently followed methods...

 Exploitation of different kinds of mineral deposits is currently addressed to recover mostly the main product from an ore, with little effort either for its co-/by-products or for value-addition and creation of wealth from waste. Presently, mineral industry is facing many problems that make it less attractive for old and new entrepreneurs. To overcome them, there is a need for ‘Mega-, Micro- and Nano (10-9)-Scale’ (MMNS) investigations on both working and potential ore deposits. Salient aspects of these multi-disciplinary and multi-faceted, both field- and laboratory-based, investigations, together with their main objectives, during different stages of ‘Mineral Exploration and Exploitation’ (MEE) are presented. Brief description of some major explored and exploited ore deposits in India, along with their possible, high-value by-products, and waste from a few mining industries, both recommended for research, are listed. Nano-scale mineral technology, presently in its initial stage, ...

Exploitation of different kinds of mineral deposits is currently addressed to recover mostly the main product from an ore, with little effort either for its co-/by-products or for value-addition and creation of wealth from waste. Presently, mineral industry is facing many problems that make it less attractive for old and new entrepreneurs. To overcome them, there is a need for 'Mega-, Micro-and Nano (10-9)-Scale' (MMNS) investigations on both working and potential ore deposits. Salient aspects of these multidisciplinary and multi-faceted, both field-and laboratory-based, investigations, together with their main objectives, during different stages of 'Mineral Exploration and Exploitation' (MEE) are presented. Brief description of some major explored and exploited ore deposits in India, along with their possible, high-value by-products, and waste from a few mining industries, both recommended for research, are listed. Nano-scale mineral technology, presently in its initial stage, may be effectively used to isolate valuable elements or molecules from ore and gangue minerals as well as has the potentiality for 'Recycling and Reusing' (R & R) of waste material, thereby serving the twin concept of value-addition and creation of wealth from waste. Some pertinent problems of mineral industry, which can be tackled by comprehensive MMNS studies, and some requiring future Research and Development (R & D), as well as expected results of such research are given. The objectives of these studies on ore deposits are (i) maximum recovery of both the main and valuable co-/by-products from ores for value-addition, (ii) utilization of their waste material for creation of wealth from waste and (iii) expansion and cost-effective development of mineral resources in mining and industrial areas of India.