Geology Reference
In-Depth Information
Exergy cost, kWh
x after
beneficiation
x in waste
rock or in
tailings
x mine
Fig. 14.5 How the mining process either concentrates or disperses minerals, once extraction has
been completed
amongst other metals including iron, stainless steel, precious metals, as well as
solder, PbO and BaO glass, phosphorous powder, ceramics, wood, various plastics,
epoxy and electronics when evaluating the waste cycle. The CRT is one case where
a widely spread global technology came to an abrupt and somewhat unforeseen
end very quickly. Substituted by LCD flat panels, amongst others, it is now a
dead technology having been withdrawn from the consumer market completely since
2006
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. The superior technology of LCDs over CRTs, whilst providing sharper
quality pictures and thinner, lightweight designs may appear “greener” but does
in fact come at an environmental price, inducing higher consumptions of scarcer
metals such as In and Sn. Such innovations could then run the risk of, what the
authors' refer to as the material rebound effect
12
.
In fact, after a set of extremely complex recovering unit operations, a CRT could
potentially provide the following materials: Al;Mg;Si;PbO;Fe
2
O
3
, Fe
3
O
4
;ZnO;
Sb
2
O
3
;W;Cr;ZnS;Y
2
O
3
;Eu;Ag;Au; Pt;Pd;Rh;Pb, Cu;Bi;Ni;Co;As;Sb;Sn,
Se;Te;ln; Zn;Fe;S;Cd, Hg;Tl;F;Cl; Br, Al
2
O
3
;CaO; SiO
2
;MgO, Cr
2
O
3
;BaO;
TiO
2
, Na
2
O;Ta;SrO, [C
3
H
6
]n , [C
2
H
3
Cl]n, [C
11
H
22
N
2
O
4
]n, epoxy and
wood. Should no recycling occur, these materials in the worst possible scenario
will enter into landfill before becoming eventually dispersed. Urban mining could
however be ultimately used for reclaiming them from waste and thus closing the
material's cycle.
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For more information, see: http : ==www:standard:co:uk=news=the future is flat
as dixons withdraws sale of big box televisions 7081231:html and http :
==usatoday30:usatoday:com=tech=products=gear=2006 10 22 crtdemise_x:htm.
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The rebound effect which is also commonly known as the Jevons Paradox expresses the fact that
an improvement in e
ciency paradoxically results in additional consumption. A thorough study
of the rebound effect may be consulted in Sorrell (2007).
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