Geology Reference
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already arrived to Thanatia (this is why incidentally in Fig. 4.1, “Stock in Landfills”
is overlapped with “Thanatia”).
That said however, the so called “urban mining” (Sec. 14.4), defined as the
recovery of secondary resources from technospheric stocks (Brunner and Rechberger,
2004) offers an opportunity to recover minerals before they are completely lost
forever. Yet the fact remains that it is far from an attractive solution, given its
energy intensity, especially when compared to recycling - a process found earlier in
the cycle. Mathematically, the material's cycle of Fig. 4.1 can be expressed as in
Eq. (4.1):
Mat. Input - Mat. Output + Recycling = Stock variation + Dissipation (4.1)
By extracting the ore from a mine, the quality (or exergy) of the ore increases,
even though an even greater amount of external exergy (effort) is spent in the pro-
cess. The raw material backpack has thus two components: one is the overall impact
of a given mineral's extraction and the other, the debt generated in provoking dis-
persion. Each particular raw material has an environmental cost associated with
its dispersal
2
. So anything that reduces new extraction is positive: substitution
3
,
miniaturisation, recycling, material use and extraction e
ciency, as will be exten-
sively discussed in Chap. 16. From the standpoint of future generations having
raw material in a “store” instead of in the mine would be a good inheritance. All
associated environmental impacts would then simply be a matter of the past. This
is something similar to the ancients leaving of the pyramids or the cathedrals for
humanity's future enjoyment.
The problem for the future generations, seeing as minerals are not placed in
stores, arises with dispersion. Anything which ends up dispersed coupled with an
increased demand requires replacement, either by recycling or yet more extraction.
Each time Man draws on non-renewable resources, without replenishing them, they
become irreversibly lost. Yet there is no way of appraising which valuable ma-
terials mankind has already lost or set to lose forever. This is because scarcity
and the effort needed to replace non-renewable resources is absent in conventional
accounting methodologies.
Dispersion is thus the key to understanding the pathway of raw materials and
the need to develop new and more robust accounting systems and methodologies.
But dispersion of raw materials has not been su
ciently considered in economic
analyses. It has been ignored as a materials availability loss and it is viewed as a
pollution problem, more than anything else. Dispersion is thus only accounted by
material balance (as occurs with heat in energy balances):
Extraction + Recycling - Societal stock = Dispersion (4.2)
2
Dissipation also occurs in previous stages of a mineral's (i.e. in the manufacturing as well as
the use stages).
3
Under this light, substitution of a raw material for another would make sense if both parts of
the backpack decrease.
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