Charcoal iron is the substance created by the
smelting
Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron-making, iron, copper extraction, copper ...
of
iron ore
Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the f ...
with
charcoal
Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, ca ...
.
All ironmaking
blast furnaces
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being supplied above atmospheric pressure.
In a ...
were fueled by charcoal until
Abraham Darby introduced
coke as a fuel in 1709. The more economical coke soon replaced charcoal in British furnaces, but in the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
, where timber for charcoal was abundant, charcoal furnaces lingered much longer. Even after the introduction of
anthracite smelting to the US in 1839, and the development of American coke production later in the century, charcoal iron continued to find favor because of its heat-resistance, toughness, and malleability. The last charcoal furnace in the US did not close until 1945.
In Britain, the penultimate furnace built was Alderwasley in 1764, followed by Warsash Furnace in 1869. The last working furnace at
Backbarrow converted to coke in 1922.
In
Western Australia
Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...
, pig iron was made using charcoal between 1948 and 1981 at
Wundowie.
At its peak, operating two charcoal-fueled blast furnaces, the
Wundowie charcoal iron and wood distillation plant produced 52,262 tons of iron in 1960/61.
There are still charcoal-based iron and steel making operations in the Brazilian state of
Minas Gerais
Minas Gerais () is one of the 27 federative units of Brazil, being the fourth largest state by area and the second largest in number of inhabitants with a population of 20,539,989 according to the 2022 Brazilian census, 2022 census. Located in ...
.
The traditional Japanese
tatara furnace uses charcoal and
ironsand to produce a mixture of iron and steel. Small quantities are still made by the
Nittoho Tatara in Japan. The tatara smelting process involves
direct reduction read online, part I, pp. 240; 250-254; 257. (capacity 650,000 t/year).(fr) Adolf Ledebur (trans. Barbary de Langlade revised and annotated by F. Valton), ''Manuel théorique et pratique de la métallurgie du fer, Tome I et Tome II'', t. 2, Librairie ...
and—unlike a
blast furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being supplied above atmospheric pressure.
In a ...
—at no time is the product fully molten. The smelted iron remains in the furnace for an extended period until much of the iron has converted to ''
tamahagane
is a type of steel made in the Japanese tradition. The word means 'precious', and the word means 'steel'. is used to make Japanese swords, daggers, knives, and other kinds of tools.
The carbon content of the majority of analyzed Japanese s ...
'', a
steel suitable for making swords.
See also
*
Harrison Ainslie
The firm of Harrison Ainslie & Co. was a British firm of ironmasters and iron ore merchants, selling high quality haematite from their mines on Lindal Moor to smelters in Glasgow, Scotland, South Wales and the Midlands. From a 21st-century pers ...
*
Wundowie charcoal iron and wood distillation plant
References
Bibliography
*
*
{{DEFAULTSORT:Charcoal Iron
Ferrous alloys
Charcoal