Lignite

Lignite
For other uses, see Lignite (disambiguation).
Lignite
Lignite briquette
Strip mining lignite at Tagebau Garzweiler near Grevenbroich, Germany

Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad, is a soft brown fuel with characteristics that put it somewhere between coal and peat. It is considered the lowest rank of coal; it is mined in Germany, Russia, the United States, India, Australia and many European countries, and it is used almost exclusively as a fuel for steam-electric power generation. Up to 50% of Greece's electricity and 24.6%[1] of Germany's comes from lignite power plants.

Characteristics

Lignite is brownish-black in color and has a carbon content of around 25-35%, a high inherent moisture content sometimes as high as 66%, and an ash content ranging from 6% to 19% compared with 6% to 12% for bituminous coal.[2]

The energy content of lignite ranges from 10 - 20 MJ/kg (9-17 million BTU per short ton) on a moist, mineral-matter-free basis. The energy content of lignite consumed in the United States averages 15 MJ/kg (13 million BTU/ton), on the as-received basis (i.e., containing both inherent moisture and mineral matter). The energy content of lignite consumed in Victoria, Australia averages 8.4 MJ/kg (6.5 million BTU/ton). When reacted with quaternary amine, amine treated lignite (ATL) forms. ATL is used in drilling mud to reduce fluid loss.

Lignite has a high content of volatile matter which makes it easier to convert into gas and liquid petroleum products than higher ranking coals. However, its high moisture content and susceptibility to spontaneous combustion can cause problems in transportation and storage. However, it is now known that efficient processes that remove latent moisture locked within the structure of brown coal will relegate the risk of spontaneous combustion to the same level as black coal, will transform the calorific value of brown coal to a black coal equivalent fuel while significantly reducing the emissions profile of 'densified' brown coal to a level similar to or better than most black coals.[3]

Uses

Because of its low energy density and typically high moisture content, brown coal is inefficient to transport and is not traded extensively on the world market compared with higher coal grades. It is often burned in power stations constructed very close to any mines, such as in Australia's Latrobe Valley and Luminant's Monticello plant in Texas. Primarily because of latent high moisture content of brown coal, carbon dioxide emissions from traditional brown coal fired plants are generally much higher than for comparable black coal plants, with the world's highest emitting being Hazelwood Power Station, Victoria.[4] The operation of traditional brown coal plants, particularly in combination with strip mining, can be politically contentious due to environmental concerns.[5][6]

Geology

Lignite is geologically younger than higher-grade coals, originating mainly in the Tertiary period.

The Latrobe Valley in the state of Victoria, Australia contains estimated reserves of some 200,000 million tonnes (Mt) of brown coal. The deposit is equivalent to 25% of known world reserves. The coal seams are generally of considerable thickness (to 300 metres) and are covered by very little overburden (2 to 5 metres).[7]

Types

Lignite can be separated into two types. The first is xyloid lignite or fossil wood and the second form is the compact lignite or perfect lignite.

Although xyloid lignite may sometimes have the tenacity and the appearance of ordinary wood it can be seen that the combustible woody tissue has experienced a great modification. It is reducible to a fine powder by trituration and if submitted to the action of a weak solution of potash it yields a considerable quantity of ulmic acid.[8]

Production

Lignite mined in millions of metric tons[citation needed]
Country 1970 1980 1990 2000 2001 2011
 Germany 369.3 388.0 356.5 167.7 175.4
 Russia 127.0 141.0 137.3 86.4 83.2
 United States 5.4 42.3 82.6 83.5 80.5
 Australia 24.2 32.9 46.0 65.0 67.8
 Greece 8.1 23.2 51.7 63.3 67.0
 Poland 32.8 36.9 67.6 61.3 59.5
 Turkey 4.4 15.0 43.8 63.0 57.2
 Czech Republic 67.0 87.0 71.0 50.1 50.7
 People's Republic of China 13.0 22.0 38.0 40.0 47.0
 SFR Yugoslavia 26.0 43.0 60.0 - -
 Serbia and Montenegro - - - 35.5 35.5
 Romania 14.1 27.1 33.5 17.9 29.8
 North Korea 5.7 10.0 10.0 26.0 26.5
Total 804.0 1,028.0 1,214.0 877.4 894.8

Reserves

Lignite reserves metric tons
Country 2011
 Kosovo[9] 14,000 billion[10]
 Germany -
 Russia -
 United States -
 Australia -
 Greece -
 Poland -
 Turkey -
 Czech Republic -
 People's Republic of China -
 Serbia and Montenegro -
 Romania -
 North Korea -
Total 14

See also

Crystal energy.svg Energy portal

References

  1. ^ "Nuclear power? Um, maybe". The Economist. 2010-09-02. http://www.economist.com/node/16947258. Retrieved 2010-09-05. 
  2. ^ Ghassemi, Abbas (2001). Handbook of Pollution Control and Waste Minimization. CRC Press. pp. 434. ISBN 0824705815. 
  3. ^ George, A.M.. State Electricity Victoria, Petrographic Report No 17. 1975; Perry, G.J and Allardice, D.J. Coal Resources Conference, NZ 1987 Proc.1, Sec. 4.. Paper R4.1
  4. ^ "Hazelwood tops international list of dirty power stations". World Wide Fund for Nature Australia. http://www.wwf.org.au/news/n223/. Retrieved 2008-10-02. 
  5. ^ "The Greens Won't Line Up For Dirty Brown Coal In The Valley". Australian Greens Victoria. 2006-08-18. http://www.vic.greens.org.au/news/media-releases-2006/the-greens-won-t-line-up-for-dirty-brown-coal-in-the-valley. Retrieved 2007-06-28. 
  6. ^ "Greenpeace Germany Protests Brown Coal Power Stations". Environment News Service. 2004-05-28. Archived from the original on 2007-09-30. http://web.archive.org/web/20070930203414/http://www.ens-newswire.com/ens/may2004/2004-05-28-02.asp. Retrieved 2007-06-28. 
  7. ^ Australian Mines Atlas
  8. ^ Mackie, Samuel Joseph (1861). The Geologist. Original from Harvard University: Reynolds. pp. 197–200. http://books.google.com/books?id=SzsFAAAAYAAJ&pg=PA199&dq=Xyloid+coal#PPA198,M1. 
  9. ^ http://www.forexpros.com/news/stock-market-news/interview-canada%27s-avrupa-targets-kosovo-lead,-zinc-201638
  10. ^ http://www.forexpros.com/news/stock-market-news/interview-canada%27s-avrupa-targets-kosovo-lead,-zinc-201638

External links

v · d · eCoal in nature
Coal by grade
Coal combustion
Coal mining
Coal types are ordered by grade. 1: peat is considered a precursor to coal, while graphite is only technically considered a coal type

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  • lignite — [ liɲit ] n. m. • 1765; lat. lignum « bois » ♦ Charbon fossile, noir ou brun, compact, composé à 70% de carbone, riche en débris ligneux. Gisement de lignite. Lignite noir et brillant. ⇒ jais. ● lignite nom masculin (latin lignum, bois) Charbon… …   Encyclopédie Universelle

  • Lignite — Lignite, ND U.S. city in North Dakota Population (2000): 174 Housing Units (2000): 111 Land area (2000): 0.139831 sq. miles (0.362161 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.139831 sq. miles (0.362161… …   StarDict's U.S. Gazetteer Places

  • Lignite, ND — U.S. city in North Dakota Population (2000): 174 Housing Units (2000): 111 Land area (2000): 0.139831 sq. miles (0.362161 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.139831 sq. miles (0.362161 sq. km) FIPS …   StarDict's U.S. Gazetteer Places

  • Lignite — Lig nite (l[i^]g n[imac]t), n. [L. lignum wood: cf. F. lignite.] (Min.) Mineral coal retaining the texture of the wood from which it was formed, and burning with an empyreumatic odor. It is of more recent origin than the anthracite and bituminous …   The Collaborative International Dictionary of English

  • lignite — imperfectly formed coal, 1808, from French, from L. lignum wood (see LIGNI (Cf. ligni )). Brown coal that still shows traces of the wood it once was. Probably directly from Lithanthrax Lignius, name given to woody coal by Swedish chemist Johan… …   Etymology dictionary

  • lignite — s. f. Carvão fóssil …   Dicionário da Língua Portuguesa

  • lignite — ► NOUN ▪ soft brownish coal, intermediate between bituminous coal and peat. ORIGIN from Latin lignum wood …   English terms dictionary

  • lignite — [lig′nīt΄] n. [Fr: see LIGNEOUS & ITE1] a usually soft, brownish black coal in which the texture of the original wood can often still be seen: in the process of coalification it represents the intermediate stage in density and amount of carbon… …   English World dictionary

  • Lignite — Le lignite est une roche sédimentaire composée de restes fossiles de plantes (vient de Lignine). C est une roche intermédiaire entre la tourbe et la houille …   Wikipédia en Français

  • lignite — lignitic /lig nit ik/, adj. /lig nuyt/, n. a soft coal, usually dark brown, often having a distinct woodlike texture, and intermediate in density and carbon content between peat and bituminous coal. [1800 10; LIGN + ITE1] * * * Yellow to dark… …   Universalium

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