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Ch.4. Asbestos in the Environment
Introduction Properties and uses Brief history Environmental hazards
IntroductionAsbestos: asbestoz “inquenchable” “inextinguish-
able”Fibrous silicate minerals: serpentine & amphiboles
○ White, brown, blue & others
tremolite
crocidolite
chrysotile
Asbestos fibre
From http://en.wikipedia.org/wiki/Asbestos
Properties & UseProperties:
○ Mineral: insulation (heat, electricity), resistance against fire & chemical reaction, incombustibility
○ Fibre: flexibility, capability of being woven, sound-absorbing
Uses○ (See the table on the next page)
Properties Application examples
Fire resistance,flame retardance,heat insulation
Building materials- interior and outsideFire-proof materials, e.g. clothsSeals for heaters and ovensHeat insulators
Electric insulationInsulators for pipes and electrical devicesCommutators
Resistance against chemical reactions (corrosion)
Chemical filters, PaintsGasketsExperimental apparatuses
Sound absorption Sound absorbing board
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Brief HistoryB.C. ca. 3,000 Scandinavian remains – used in
porcelain and filler among the logs1C : Greek island Evvoia – Asbestos mining
querryEarly Greek-Roman: unflammable clothes and
building materialsPliny the Elder: Thought to be used for the pro-
tection from the curse
Pliny the Elder (23-79), a.k.a. Caius Plinius Secundus, Gaius Plinius Secundis. Author of the grand encyclopedia "Naturalis Historiae".
Ancient Egyptian: Used for Parao’s mummyAncient Persian: Imported from China, Used for
the cloths for deaths, thought as feather of sara-manda (phoenix)
Others: Lamp wick of tomb, Cure for itching
Saramanda on a tile from ancient Iranian heritage
http://www.metmuseum.org
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In medieval times, asbestos was frequently used for the insulation of armor
Some fraud merchants made cross with asbestos and deceive people with it as if that was a part of the cross on which Jesus Christ was nailed (hung, executed)
19C: Industrial revolution also trigger modern application of asbestos○ Used as heat insulator in USA & Canada in 1860’s○ First commercial asbestos mine in Quebec,
Canada, in 1879.20C: rapid increase of asbestos consumptionAfter 1970’s: Health threats (hazards) by as-
bestos became obvious invoke lot of regula-tions against asbestos usage. Ban of asbestos usgae Sudden decrease of asbestos con-sumption
Now, the usage of asbestos is banned or limited in most countries
For Korea,○ From 2009.09, asbestos is banned to be used in
any industrial product○ From 2007.07, any product containing asbestos is
banned to import, produce, or use.
World Asbestos Resources
Country Reserve Base
(By Principal Countries)
Brazil Moderate
Canada Large
China Large
Kazakhstan Large
Russia Large
USA Large
Zimbabwe Moderate
Other Countries Large
World Total Large
Source : Mineral Commodity Summaries, 2004.
World Asbestos Producers
Country 2001 2002 2003
(By Principal Countries) Production of Asbestos(in '000' tonnes)
Brazil 173 195 231
Canada 262 216 174
China 258 220(e) 210(e)
Kazakhstan 271 291 353
Russia 735 775(e) 878(e)
Zimbabwe 119 168 130
Other Countries 82 135 24
World Total 1900 2000 2000
Source : World Mineral Production. 1999-2003.