Understanding Chrome

Chromite Ores General Information

Chromium was first discovered as a metal in the 17th century, but it was only in the 18th century before it was used commercially.

In the 20th century, the use of chromium exploded due to the industrialization and surge in demand for stainless steel. Chromium usage can be divided into 3 categories:

Chromite ores are converted into ferro chrome through smelting with carbon or silicon. Metallurgical ferro chrome major usage is the production of stainless steel.

Chromium biggest benefit in the metallurgy ferro chrome usage is its corrosion resistance, hardness, strength and bright furnish. These benefits allows ferro chrome to be used in the production of stainless steels, and heat resistant steel. In the production of stainless steel, the use of ferro chrome has no substitute, so as long as stainless steels are being produced worldwide, the demand for chromite ores will exist. Up to 25% of the weight of stainless steel is ferro chrome.

South Africa is the largest producer of chromite ores, where over 70% of world chromite ore reserves are believed to be located. Today South Africa supplies approximately 50% of world's supplies of chromite ores.

Other countries playing a significant role in the supply of chromite ores are Kazakhstan, India, Turkey, Zimbabwe, Russia, Brazil, Finland, Australia, Iran and Oman. The total worldwide production of chromite ore is approximately 20 million metric tons per year.

Ferrochrome

Ferrochrome is a corrosion-resistant alloy of chrome and iron containing between 50% and 65% chrome. It is a finishing material which contains about 50-70% (depending on ore used a the producer) chromium alloyed with iron. Most of the world's ferrochrome is produced in South Africa, Kazakhstan and India, which have large domestic Cr Ore resources. Increasing amounts coming from Russia and China.

Over 80% of the world's ferrochrome is utilised in the production of stainless steel. Stainless steel depends on chrome for its appearance and its resistance to corrosion. The average chrome content in stainless steel is approximately 18%. It is also used when it is desired to add chromium to carbon steel. FeCr from Southern Africa know as 'charge chrome' produced from a Cr containing ore with a low Cr content is most commonly used in stainless steel production, where as High Carbon FeCr produced from high grade ore found in Kazakhstan is more commonly used in specialist applications such as engineering steels where a high Cr to Fe ratio and minimum levels of other elements such as Sulfur, Phosphorus and Titanium are important and production of finished metals takes place in small electric arc furnaces compared to large scale blast furnaces.

Ferrochrome production is essentially a carbothermic reduction operation taking place at high temperatures. Cr Ore (an oxide of chromium and iron) is reduced by coal and coke to form the iron-chromium alloy. The heat for this reaction can come from several forms, but typically from the electric arc formed between the tips of the electrodes in the bottom of the furnace and the furnace hearth. This arc creates temperatures of about 2800°C. In the process of smelting, huge amounts of electricity are consumed making production in countries with high power charges very costly.

Tapping of the material from the furnace takes place intermittently. When enough smelted ferrochrome has accumulated in the hearth of the furnace, the tap hole is drilled open and a stream of molten metal and slag rushes down a trough into a chill or ladle. The ferrochrome solidifies in large castings, which is crushed for sale or further processed.

Ferrochrome is often classified by the amount of carbon and chrome it contains. The vast majority of FeCr produced is charge chrome from Southern Africa. With high carbon being the second largest segment followed by the smaller sectors of low carbon and intermediate carbon material.

Ferrochrome Production

Surging demand for ferrochrome used in making ferroalloy, which in turn is used in making stainless steel, has led to a severe shortage of chromite. Such supply condition is driving up prices of chrome ore.

Ferrochrome production for metallurgical applications uses up more than 90% of the worlds chromite output of about 19 M tonnes/y. Non-metallurgical applications consume only a fraction of chromite production, with the refractory industry accounting for only about 1% and 3% each for the foundry and chemical industries.

The non-metallurgical industry is dependent on chromite requirements of the metallurgical industry as most chromite is manufactured by vertically integrated ferrochrome producers.

Major traders of non-metallurgical chromite from South Africa provide more than half of global chromite supply. The declining availability of chromite is becoming alarming, especially when non-metallurgical applications are indicating increased demand for the material. The International Chromium Development Association noted that the metallurgical and foundry sectors both achieved an increase of about 10% in chromite consumption in 2005. Refractory consumption rose by 19.5% from 101,000 tonnes to 125,000 tonnes in 2005, while the chemical industry's chromite use dropped 21% from 752,000 tonnes to 595,000 tonnes.

The supply shortage is mainly attributed to the booming stainless steel industry, which consumes more than 90% of the world's ferrochrome supply. Prices have also soared, with non-metallurgical chromite consumers compelled to match metal prices to ensure supply.

Prices recently climbed further due to several developments, including a new tariff imposed by India on chromite exports; and speculations that South Africa is considering a new legislation that would ban the export of unbeneficiated chromite. South Africa accounts for about 50% of global chromite production, followed by India and Kazakhstan with about 20% and 15%, respectively. Demand for chromite and ferrochrome is expected to remain strong mainly due to the continued growth of China's stainless steel industry