Lime (mineral)




Lime is a general term for various naturally occurring calcium predominate.

These materials are used in large quantities as building and engineering materials (including chemical feedstocks, among other uses. Lime industries and the use of many of the resulting products date from prehistoric periods in both the Old World and the New World.

The rocks and minerals from which these materials are derived, typically calcium hydroxide, Ca(OH)2), the process of which is called slaking of lime.

When the term is encountered in an agricultural context, it probably refers to quicklime or burnt lime.

Lime production process

  • Limestone is extrated from quarries or mines.
  • Part of the extracted stone, selected according to its chemical composition and granulometry, is calcinated at about 1000°C in different types of kiln, fired by such fuels as natural gas, coal, fuel oil, lignite, etc..
Quicklime is produced according to the reaction : CaCO3 + heat --> CaO + CO2
  • Quicklime can be hydrated, i.e. combined with water.
Hydrated lime is produced according to the reaction : CaO + H2O --> Ca(OH)2
  • Animation presentating the lime production process

Main lime producers

Lhoist, Carmeuse, Graymont, Mississippi Lime, Felswerke, Nordkalk, Schaefer Kalk, PPC Lime...

See also

  • calcium hydroxide
  • gypsum: a similar mineral.
  • sascab: a building and paving material (Central America).
  • hydraulic lime
  • J.A.H. Oates, Projet de. Lime and Limestone – Chemistry and Technology, Production and Uses. Wiley-VCH, ISBN 3-527-29527-5 (1998)
  • US Geological Survey

Sources

  • The National Lime Association (US & Canada)
  • Carmeuse Group website
  • Glossary by Robert W. Piwarzyk, Santa Cruz Public Libraries, Ca


 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Lime_(mineral)". A list of authors is available in Wikipedia.