The Heaton process is one of the 18th century processes for refining pig iron without the use of charcoal.
Inventors
John Heaton developed this process using
nitrate
Nitrate is a polyatomic ion
A polyatomic ion, also known as a molecular ion, is a covalent bonded set of two or more atoms, or of a metal complex, that can be considered to behave as a single unit and that has a net charge that is not zer ...
s to oxidize the 2-5% carbon in cast iron and convert it to steel.
Process
In 1869, when John Heaton published 'Heaton's Process for the Treatment of Cast Iron and the Manufacture of Steel',
cast iron
Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
was a readily available material, but converting it to
steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
was a slow, expensive, laborious process. At the time, there was an already-known laboratory-scale process of adding "
nitre
Niter or nitre is the mineral form of potassium nitrate, KNO3. It is a soft, white, highly soluble mineral found primarily in arid climates or cave deposits.
Historically, the term ''niter'' was not well differentiated from natron, both of w ...
" to cast iron in order to produce oxygen and burn off the carbon, producing steel. John Heaton formalized a process (specifying
sodium nitrate
Sodium nitrate is the chemical compound with the formula . This alkali metal nitrate salt is also known as Chile saltpeter (large deposits of which were historically mined in Chile) to distinguish it from ordinary saltpeter, potassium nitrate. T ...
instead of potassium) and designed equipment which made the comingling of the nitrate and the liquid cast iron reliable and repeatable, something that had until then been impractical. Combined, these improvements became the Heaton process. Another English
metallurgist
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys.
Metallurgy encompasses both the sc ...
,
Henry Bessemer
Sir Henry Bessemer (19 January 1813 – 15 March 1898) was an English inventor, whose steel-making process would become the most important technique for making steel in the nineteenth century for almost one hundred years from 1856 to 1950. He ...
had just created the
Bessemer process
The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron before the development of the open hearth furnace. The key principle is steelmaking, removal of impurities from the iron by ox ...
of blowing air or pure
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
through liquid cast iron to burn off the carbon.
Heaton conducted a long and protracted legal battle with
Henry Bessemer
Sir Henry Bessemer (19 January 1813 – 15 March 1898) was an English inventor, whose steel-making process would become the most important technique for making steel in the nineteenth century for almost one hundred years from 1856 to 1950. He ...
who believed that the Heaton Process was included in the Bessemer process through some early patent applications. Eventually the courts found in favor it Heaton, but it was Bessemer's process that won out in the end.
Adoption
As of 1869 it was not clear, if it was "sufficiently economical" to justify the conversion of existing plants
It was soon eclipsed by the
Bessemer process
The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron before the development of the open hearth furnace. The key principle is steelmaking, removal of impurities from the iron by ox ...
.
See also
*
Bessemer process
The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron before the development of the open hearth furnace. The key principle is steelmaking, removal of impurities from the iron by ox ...
*
Puddling
*
Potting and stamping Potting and stamping is a modern name for one of the 18th-century processes for refining pig iron without the use of charcoal.
Inventors
The process was devised by Charles Wood of Lowmill, Egremont in Cumberland and his brother John Wood of We ...
References
{{reflist
Steelmaking