The Peregrination of Iron Ore
From the Mines of Orissa to Industries
-Muskan Singh
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A little about mines of Orissa
Possessing an important position on India’s map, Orissa’s rich mineral resources contain 28% of Iron ore, 59%of Bauxite, 24% of Coal and 98% of chromite of total mineral deposit of India. This has attracted many metallurgical and mining companies to Orissa, such as Tata Steel, Jindal, and so on. Rayagada areas, Joda Barbil area, Rajgangpur Area, Hirakud area are some of the industrially active zones of Orissa. The districts of Mayurbhanj, Keonjhar, Sundargarh and Jajpur are rich in iron ore deposits.
Figure 1
The Jamda-koira valley of Orissa embraces one of the foremost and massive iron ore deposits of high grade hematite ore which is related to the Archean Banded Iron Formation. These deposits are unearthed in the Keonjhar–Sundergarh districts of Orissa and south of West Singhbhum district of Jharkhand. The total reserve of iron ores in this belt amounts to about 8.8 billion tons, which constitutes around 60% of India’s hematite iron ore reserve base[1].
Various forms of Iron ore
The iron ores of this region primarily embody a blend of hematite, magnetite and goethite typologies, aluminum-bearing minerals such as gibbsite and kaolinite, and quartz. Several research analyses were carried out to study the texture, mineralogy and chemical composition of iron ore found in this region to understand the composition of goethite with respect to Al2O3, Fe, P and SiO2, indispensable for upgradation of quality of iron ore and steel making.
Figure 2
The two major ores of Iron are hematite and magnetite, however, over the past few decennia, hematite ore is largely used as a raw material by the industries as magnetite ore sticks to the metallic blast furnace, owing to its relatively high magnetic properties.
Normally, steel industries require iron ores of high level of iron content and low percentage of impurities of Al2O3, S, P and SiO2. The operation of iron and steel making is more reliant on particle size of the feed and its chemical composition than on mineral abundance, texture or composition.
After the extraction of iron ore from the earth’s crust, the processing of the ore is carried out. The series of steps involved in this are crushing, screening, washing, and in a few cases, beneficiation and agglomeration. Crushing and screening are primarily used for sizing the ore and also for removal of the gangue minerals adherent to the ore. Additionally, dry and wet grinding is utilized in a few cases.
Figure 3
Different Semblance of Iron ore based on particle size
Iron ore is chiefly utilized for production of sponge iron, pig iron and steel, and for each of these types, a particular kind of iron ore is required.
After blasting the hematite ore, it is converted into lumps of size 80mm and above. Further, these lumps of iron ore are crushed to get fines of particle size range of about 5-15mm. The fines which are burnt are called “sponge iron” and are used to make steel. Sponge and fines iron ore are called calibrated iron ore. Although, in the mines of Orissa, fines are predominantly produced in three grade ranges- below 58% (low grade), above 58% and below 62 % and above 62% (high grade). Fines are transformed into sinters to maneuver in steel plants while concentrates/fines are utilized to make pellets, principally exported and employed for internal consumption in sponge iron units.
In India, the basic requirement for blast furnaces are 40mm to 10mm sized ore with iron content more than 64% and the sintering plants need 10mm to 0.15mm ore with iron content more than 63%. Iron ore with iron content more than 67% Fe and particle size less than 150mm is utilized for making pellets. In direct sponge iron making for direct reduction course, the calibrated ore of iron content more than 65% and 18 to 5mm size is used. The iron ore is characterized in terms of its grain morphology, mineralogy and microstructure, and although these parameters play a very significant role in iron making, however they are not given much importance.
Owing to the subsiding amount of lumpy iron-ore of high-grade and the availability of huge quantities of low-grade iron ores in the form of fines, numerous steel plants around the globe are adapting to agglomerates of fine ores as feedstock of blast furnaces. With elevated interest in low-grade iron ore that comprises a high percentage of Al2O3, S, P and SiO2, and due to wastage on ignition, it becomes essential to merge the mineralogical parameters to evaluate the ore properties and efficiency of the process.
Figure 4
To guarantee easy accessibility of raw substances, i.e., different forms of iron ore in the domestic market at affordable prices, the export duty of 30 % for iron content above 58% and 0% for iron content below 58% Fe was imposed on iron ore pellets.
According to a report, in several industries like Sponge Iron, Iron & Steel, Alloysteel, Ferro-alloys, Coal Washery and Cement, about 142.53 million tonnes of iron ore were engrossed. The extensive patrons of iron ore were Sponge Iron (15.7 %) and Iron & Steel (83.6%) industries. These industries were responsible for over 99.3 % consumption
Figure 5
Major Industries in Orissa
One of the most salient information about mining in Orissa is that, The Government of Orissa has leased certain zones of the Orissa mines to several major industries in order to extract the iron ore for utilizations and sale purposes. Some of these industries are-
• ADHUNIK METALIKS LIMITED
• BHUSHAN POWER & STEEL LTD.
• CONCAST STEEL & POWER LTD.
• THAKUR PRASAD SAO & SONS PVT. LTD. UNIT-IV
• JINDAL STAINLESS LIMITED
• ORISSA SPONGE IRON & STEEL LIMITED
• PATNAIK STEELS AND ALLOYS LIMITED
• RUNGTA Mines LTD.
• TATA STEEL LTD.
Overview of distinct sales prices of Iron ore
The below two graphs depict the average sale price of iron ore In Orissa by grades for which royalty is chargeable on ad valorem basis for the month of MARCH 2011.
The above graph depicts the average sale price of iron ore In Orissa by grades for which royalty is chargeable on ad valorem basis for the month of MARCH 2020.
Amidst 2016-2017, in terms of volume total export of iron ore encompasses fines of iron ore (60%), pellets of iron ore (29%), lumps of iron ore (7%), iron ore non-agglomerated concentrate (4%), and iron ore pyrites which were exported in trivial quantity. The primary Indian ports or export of iron ore are Haldia, Paradip and Vishakhapatnam. The major countries where India exports iron ore are China (96%) and Japan (2%), while the rest of the 2% of the exports are to Italy, Oman, Iran, Korea, Netherlands, Kenya, Nepal, etc.
Conclusion
In day to day life, we use numerous articles made of iron or steel but are unaware of the journey of these materials before they reach us. This work has attempted to provide insights into this journey of iron ore from the time it is extracted from the earth’s crust till before it reaches the industry.
Acknowledgement
My sincere gratitude towards Mr. Prakash Senapati, Lab Incharge at TCRC Petrolabs Bharat PVT LTD., Orissa and Mr. Vinay Singh, Mines Manager in Jindal Saw LTD., Rajasthan for assisting me in building up this article by providing beneficial information.
References:
Das B., Das K., Mishra K., Sakhtivel R., 2010, Mineralogy, Microstructure, and Chemical Composition of Goethites in Some Iron Ore Deposits of Orissa, India, Mineral Processing and Extractive Metallurgy Review: An International Journal, doi- http://dx.doi.org/10.1080/08827500903404948
Indian Minerals Yearbook 2017, (Part- III: Mineral Reviews), 56th edition, GOVERNMENT OF INDIA MINISTRY OF MINES INDIAN BUREAU OF MINES.
Department of Steel and Mines, Government of Orissa-http://www.odishaminerals.gov.in/MiningInOdisha/MineralBasedIndustries
Earth Sciences Museum, University of Waterloo- https://uwaterloo.ca/earth-sciences-museum/resources/detailed-rocks-and-minerals-articles/iron-ore
Image sources-
● Figure 1- https://dir.indiamart.com/rourkela/iron-ore-fines.html
● Figure 2- https://www.quora.com/Why-is-hematite-used-over-magnetite-Magnetite-has-more-iron-content
● Figure 3- https://dir.indiamart.com/rourkela/iron-ore-fines.html
● Figure 4- https://dir.indiamart.com/rourkela/iron-ore-fines.html
● Figure 5- Indian Minerals Yearbook 2017, (Part- III: Mineral Reviews), 56th edition, GOVERNMENT OF INDIA MINISTRY OF MINES INDIAN BUREAU OF MINES.
Muskan Singh
Muskan Singh is a third year BSc Student pursuing a major in Chemistry from St. Xavier's College, Mumbai. She is keenly Interested in ancient Indian culture, and passionate about classical music. She is also a former basketball player.
Muskan believes that everything in this universe is object- observer relative. She is engrossed in reading the life histories of leaders like Subash Chandra Bose and A.P.J. Abdul Kalam. In addition, she is a big fan of the television sitcom F.R.I.E.N.D.S.
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