Iron Ore production & Distribution around the World

  • Iron ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, deep purple, to rusty red.

  • The iron itself is usually found in the form of magnetite, hematite, goethite, limonite or siderite.

  • Ores containing very high quantities of hematite or magnetite (greater than ~60% iron) are known as “natural ore” or “direct shipping ore”.

  • Iron ore is the raw material used to make pig iron, which is one of the main raw materials to make steel.

Beneficiation of Iron – ore

  • Lower-grade sources of iron ore generally require beneficiation, using techniques like crushing, milling, gravity or heavy media separation, screening, and silica froth flotation to improve the concentration of the ore and remove impurities.

  • The results, high quality fine ore powders, are known as fines.

Magnetite

  • Magnetite is magnetic, and hence easily separated from the gangue minerals and capable of producing a high-grade concentrate with very low levels of impurities.

  • Mining of banded iron formations involves coarse crushing and screening, followed by rough crushing and fine grinding to comminute the ore.

  • Generally most magnetite banded iron formation deposits must be ground to between 32 and 45 micrometers in order to produce a low-silica magnetite concentrate.

  • Magnetite concentrate grades are generally in excess of 70% iron by weight and usually are low phosphorus, low aluminium, low titanium and low silica and demand a premium price.

Hematite

  • Due to the high density of hematite relative to associated silicate gangue, hematite beneficiation usually involves a combination of beneficiation techniques.

  • One method relies on passing the finely crushed ore over a slurry containing magnetite or other agent such as ferro silicon which increases its density.

  • When the density of the slurry is properly calibrated, the hematite will sink and the silicate mineral fragments will float and can be removed.

Smelting

  • Iron ores consist of oxygen and iron atoms bonded together into molecules.

  • To convert it to metallic iron it must be smelted or sent through a direct reduction process to remove the oxygen.

  • Smelting is a process of converting ore to metal by removing impurities.

Commonly found impurities in Iron Ore

Silica

  • Silica is almost always present in iron ore. Most of it is slagged off during the smelting process.

  • At temperatures above 1300°C some will be reduced and form an alloy with the iron.

  • The hotter the furnace, the more silicon will be present in the iron.

  • It is not uncommon to find up to 1.5% Si in European cast iron from the 16th to 18th centuries.

Phosphorus

  • Phosphorus (P) has 4 major effects on iron: (i) increased hardness and strength, (ii) lower solidus temperature, (iii) increased fluidity, and (iv) cold shortness.

  • The strength and hardness of iron increases with the concentration of phosphorus.

  • It affects the ductility and resistance to shock or bad impact.

Aluminium

  • Small amounts of aluminium (Al) are present in many ores including iron ore, sand and limestone.

  • The former can be removed by washing the ore prior to smelting.

  • Aluminium is very hard to reduce. As a result, aluminium contamination of the iron is not a problem.

Sulfur

  • Sulfur (S) is a frequent contaminant in coal. It is also present in small quantities in many ores, but can be removed by calcining.

  • The effects of even small amounts of sulfur are immediate and serious.

Iron ore productionList of countries by iron ore production in Tabular form
Rank Country Iron ore production
(thousand tonnes)
year
  World

3,320,000

2015
1 China

1,380,000

2015
2 Australia

824,000

2015
3 Brazil

428,000

2015
4 India

129,000

2015
5 Russia

112,000

2015
6 Ukraine

68,000

2015
7 South Africa

80,000

2015
8 United States

43,000

2015
9 Canada

39,000

2015
10 Sweden

37,000

2015
Tabular form of Pig iron production (million metric tons):
Rank Country 1980 2013 2015
  World

506

1,168 1,180
1 People’s Republic of China

38

709 710
2 Japan

87

84 84
3 India

8.5

50 54
4 Russia

n/a

50 51
5 South Korea

5.6

41 47
6 Brazil

13

26 30
7 Germany

36

27 28
8 United States

62

30 26
9 Ukraine

n/a

29 25
10 United Kingdom

6.2

9.4 9
  other countries

246

91 101
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