Recycling Solutions - Thanatia: The Destiny of the Earth's Mineral Resources - page 437

necessarily located near urban areas (Johansson et al., 2013). In this way, to de-
scribe the multiple sources where resources can be recovered, technospheric mining
is subdivided into six categories, covering in-use, hibernation, dissipation, landfill,
slag and tailing mining (Fig. 14.4). Concerning their size, in-use stock constitutes
by far the largest reservoir (estimated to comprise at least 50% of the total amount
in the technosphere (Brunner and Rechberger, 2004; Graedel et al., 2010)). Land-
fills and tailing ponds could constitute up to 10% of the technospheric resources,
whereas slag heaps, hibernating stocks and dissipated metal resources are consid-
ered to be the smallest sinks of metals making up 1-5% of the total technospheric
stocks (Johansson et al., 2013).

ec no p eric minin (Ur an minin )

andfill minin

Secondary minin

n u e i erna ion Di ipa ion andfill Sla ailin

Wa e minin

Fig. 14.4 Existing mining concepts and their connection with different stocks in the technosphere.
Adapted from Johansson et al. (2013)

In-use mining could refer to the strategic relocation of those metals already
in-use due to changed market conditions, where such metals, despite their own-
ership and present purpose, are moved toward more needed purposes (Johansson
et al., 2013). Hibernating stocks meanwhile are accumulations of obsolete materials,
that even now could be made accessible for recovery, such as those derived from
old water supply and sewage networks, gas, power and telecommunication grids or
decommissioned military and industrial structures (Krook et al., 2011). Landfill
mining refers to the extraction, processing, treatment and/or recovery of deposited
materials (Frändegard et al., 2013). Extraction from tailings and slags meanwhile
refers to the reclaiming of raw materials that are discarded during the mining and
metallurgical processes (see Sec. 14.6.1). For instance, according to Graedel et al.
(2004), around 2% of the global production of copper was obtained from reworked
tailings. Johansson et al. (2013) also cites a few examples of slag recovery from slag
heaps derived from copper and steel production, although these are very limited due
to the complexity associated with slag leaching. The final subcategory, dissipation
mining, is the most di cult to achieve. In this case, secondary metals have dissi-
pated back into the environment and with the consequence of uncertain location
and low concentrations in sea, land, and air (Johansson et al., 2013). Drawing a
parallel, the authors of this topic would refer to it as “mining from Thanatia”. Sub-
sequently, dissipation mining is rather unrealistic since it would involve a massive
use of energy.