Uses of nickel
What is nickel?
Nickel is the 5th most common element on earth. It is a naturally occurring element that exists mainly in the form of sulphide, oxide, and silicate minerals. Nickel is an extremely important commercial element, playing a key role in global industrial development and outpacing almost all other industrial metals.
The factors which make nickel and its alloys valuable commodities include strength, corrosion resistance, high ductility, good thermal and electric conductivity, magnetic characteristics and catalytic properties.
Ferronickel is an alloy containing nickel and iron - approximately 35% nickel and 65% iron.
The use of nickel is dominated by the production of ferronickel for stainless steel (66%). However, it is also used in the production of non-ferrous alloys (12%), alloy steels (5%), plating (7%), foundry (3%) and batteries (2%).
Ferronickel is primarily used in the manufacture of Austenitic stainless steels (known as 200 and 300 series). These are non-magnetic and contain between 8.5%-25% nickel, enhancing their corrosion resistance. They are the most widely used group of stainless steels, accounting for between 70%-75% of global stainless output. Ferritic stainless steels (known as 400 series) contain no ferronickel.
Today, ferronickel plays a key role in all developed and developing economies. It is used in numerous applications in all sectors: engineering, transport, electrical and electronic, building and construction, metal goods and tubular products. It also enables the production of vital products with special properties - magnetic, electronic, controlled expansion, catalytic and battery-related.
Ferronickel enables efficient telecommunications, safe transportation, effective oil and gas production, clean and reliable energy generation, hygienic processing of foods and drinks, safe and reliable medical equipment, water treatment and delivery and emission-reducing equipment from gas scrubbers to hybrid vehicles.
Ferronickel use has been highly innovative, with added value more than compensating for its relatively high cost. With this proven track record of innovation, ferronickel will play an even more important role in future society than it does today.
How ferronickel is produced
Exploration In Greece, all geological studies are performed primarily by the Institute of Geology and Mineral Exploration which provides general information on size, location and quality of various mine ores in Greece and secondary from Universities.
LARCO then conducts its own large scale geological and mineral research that includes geological surveys, mapping, sampling, deposit studies and core sampling drills, using modern drilling equipment. This exploration programme gives us vital precision in planning and opening a pit. In the last five years, the annual average number of drill holes carried out was 182, by which LARCO covered an area of 1,200,000 m2 annually.
Based on our data, nickel laterite mineral resources exceed 250 million tonnes and are mainly spread over three large areas of Greece:
- Central Euboea
- Neo Kokkino area and the county of Viotia
- Northern Greece, in the area of Kastoria.
Our aim for the future is to systematically explore nickel bearing areas both in Greece and abroad, where we possess mining rights, to find more exploitable sources, via the processes of pyrometallurgy and of heap leaching.
The two main types of nickel deposit
Nickel laterite deposits are found in two general types:
- the first is the much rarer in Greece ‘in situ’ laterites; deposits formed by chemical weathering of ultramafic rocks (ophiolites), under certain environmental conditions. Kastoria mine is an example of this.
- the second is the transported (sedimentary) type – laterites that have been eroded and transported away by gravity or water, then re-deposited in new locations. This type is more uniform and thus more easily extracted but with correspondingly lower nickel content. Agios Ioannis mines and Euboea mines are examples of this type.
Nickel is extracted through both underground and surface mining.
Underground mining uses a sub-level caving method. Access to the deposit is carried out with horizontal calcareous galleries and spiral ramps. The main phases are the drilling, the charging the drills with explosives and their firing, the collection of the produced ore and the support of the galleries. The produced ore is transported to the surface by electric railroad.
Surface mining combines open and closed pits. The height of the benches varies between 12 and 15 m, with the width depending on whether they are active benches or close to decommissioning. To begin, they are around 25 metres wide, decreasing to around 12m before decommissioning. Stripping is performed by use of explosives while cutting with bulldozers and other mechanical equipment.
Extracted ore is stored temporarily in piles before transporting for crushing and separating. The magnetic portion of the ore (concentrate) is led to the stacker system and on to the homogenization yard. The homogenized ore is loaded and transported to the smelting plant, where it is weighed and fed to the kilns for further processing.
The smelting plant is located in Larymna. The basic production line consists of 4 rotary kilns, 5 electrical furnaces and 2 OBM-type converters, with a capacity of 50 tons of metal each.
There are also secondary installations, such as 2 units for the production of oxygen and nitrogen, grinding units, and magnetic separation units. The plant operates 24 hours a day, 365 days a year, producing high-purity, low-carbon ferronickel granules, used exclusively in stainless steel production.
Click here for more on the smelting process
This end product is then transported to LARCO’s dedicated harbour for shipping.