lignite

Traductions

• anglais

  Auteur : World (The) Energy Conference, 1978

  Définition

  Combustible, solid, black to brown, fossil carbonaceous sedimentary deposit. Until reliable parameters for differentiation of brown and hard coals are worked out and confirmed, coals considered in each country as brown, on the basis of a number of other characteristics, should be classified as brown coals regardless of their calorific value, i.e. including the cases when the gross calorific value of the coal in equilibrium with air at 30 °C and 96% relative humidity is more than 24 MJ/kg on the ash-free basis.

  Notes :

  In view of the difficulty of differentiating in borderline cases between hard coal, defined ((under hard coal)), the following further identification reactions may be applied: Streak colour: light to dark brown. Humic acid reaction with KOH: brown. Lignin reaction with HNO₃: orange to reddish.
  
  Conventional use of the terms "hard coal", "brown coal" and "lignite" varies from country to country. Taking the naturally occurring solid fuels by rank, namely, wood, pear, lignite/brown coal, sub-bituminous coal, bituminous coal, semi-bituminous coal, semi-anthracite and anthracite, in the USA and Canada, anthracite is considered to be hard coal, bituminous coal is considered to be soft coal, and sub-bituminous coal is synonymous with black lignite; under the above-mentioned international classification the term hard coal includes both anthracite and bituminous coal.

  Terme :

  1. brown coal

  Terme associé :

  1. lignite