Chromium Industry Developments
History of chromium
Chromium was discovered and named by the French chemist, Louis Nicolas Vauquelin (1763-1829) in 1797, during the years of the French Revolution. The following year, he isolated the metal by reduction of the Siberian red lead ore (crocoite, PbCrO4 ) with carbon. The brilliant hue of this chromate mineral inspired Vauquelin to give the metal its current name (from Greek chrōmos, “colour”).
Chromium is chemically inert, and has a high melting point, 1907°C. It is said that the first use of chromium as an alloying agent in the manufacture of steel took place in France in the 1860s. About three quarters of the chromium produced is used in the production of stainless steel.
Chromium demand is dominated by stainless steel
World chromium consumption was 7.1 Mt in 2017 (Roskill, 2018), from 29.8 Mt of chromite. The market share of chromium is divided as follows: – 77% stainless steel – 17% other steel alloys – 3.2% chemical applications – 2.7% foundry and refractory applications. The growth in the world steel industry determines the demand for chromium (as ferrochromium).
Chromite leading producing countries
Chromite ore production has grown in many countries including South Africa (12 Mt), Kazakhstan (3.7 Mt), India (3.5 Mt), Turkey (2.6 Mt). Most of the chromite ore production was smelted in electric-arc furnaces to produce ferrochromium for the metallurgical industry.
Chromite and Ferrochromium prices follow similar trends because both are impacted by the same macro-economic factors. Most chromite is used to produce ferrochrome, and most ferrochrome is used to produce stainless steel. Chromite accounts for one third of the production cost of ferrochrome. The value (represented by price) increases dramatically as chromium is beneficiated from chromite to ferrochromium to stainless steel.
Chromite production in South Africa
During the oil crisis of the 1970s, South Africa’s plentiful and cheap coal-based thermal power helped to grow the ferro-alloys industry. South Africa has the largest known reserves of chromium ores – Bushveld Complex (PGMs, Cr, V, Ti) – close to surface, but has a lower chromium to ferrochrome ratio (about 1.6) than many other countries. The country contains the largest known layered igneous complex of its type in the world – 350 km west to east; 250 km north to south.
Southern Africa hosts about 90% of the world’s chromite reserves and resources, and accounts for close to 60% of global chromite production. South Africa has reserves of about 3.1 billion tons, and a further estimated resource of 5.5 billion tons. The country is by far the largest producing country for chromite, accounting for 54% of world output. By comparison, Kazakhstan accounts for 13%, and India 12%. In 2017, six countries produced more than 1 Mt/a of chromite (South Africa, Kazakhstan, India, Turkey, Finland and Zimbabwe). Most primary ore comes from the LG6 (Lower Group) or MG (Middle Group) chromite seams, while lower-grade chromite is recovered from the UG2 (Upper Group), which is an abundant by-product from platinum production.
Over the past decade, UG2 chromite has formed a growing proportion of the world’s chromite supply. Over the past two decades the supply of UG2 ores has risen to account for over a quarter of the annual South African chromite supply. UG2 chromite is highly reducible, and solid-state pre-reduction is feasible. UG2 chromite has lower energy requirement (per unit of ferrochromium, and per unit of chromium content).
The minerals boom of the early 2000s was driven primarily by the urbanization of China. China produces more than half of the world’s stainless steel, with demand growing at over 4% per annum. By 2006, 90% of the chromite that South Africa produced was converted to ferrochromium in South Africa, making SA by far the world’s largest producer of this ferro-alloy.