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The examples and perspective in this article may not represent a worldwide view of the subject. Please improve this article and discuss the issue on the talk page. (December 2010) |
In Europe virtually all domestic salt is obtained by solution mining of underground salt formations although some is still obtained by the solar evaporation of sea water.[1] Salt is extracted from the Brine using vacuum pans, where brine is heated in a partial vacuum in order to lower the boiling point. In the past salt has been extracted by heating the brine in pans operating at normal atmospheric pressure, known as open pans.
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The earliest examples of pans used in the solution mining of salt date back to prehistoric times and the pans were made of ceramics known as briquetage. Later examples were small (3 ft square) pans made from lead using wood as a fuel.[2] After the middle ages the pans started to be made from iron, firstly in pans 7 ft (2.1 m) by 8 ft (2.4 m). Gradually the pans increased in size until 'common' salt pans 20 ft (6.1 m) wide and 30 ft long were the norm.[2] The change from lead to iron coincided with a change from wood to coal for the purpose of heating the brine. Brine would be pumped into the pans, and concentrated by the heat of the fire burning underneath. As crystals of salt formed these would be raked out and more brine added.
The following are historical names given to occupations in open pan salt works, primarily in Cheshire, England.[3]
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