Chap. 11. Toward a Greener Anthrosphere through Industrial Ecology 289Recycling is of course one of the major objectives of a system of industrial ecology
and one in which significant progress is being made. There are some consumable items
that are not practical to recycle and for which the raw materials are abundant enough
that recycling is not required. Household detergents fall into this category. A second
group of recyclables are those that are not particularly scarce, but for which recycling
is feasible and desirable. Wood and paper fall into this category. A third category of
recyclable materials consists of metals, particularly the more valuable and scarce ones,
such as chromium, platinum, and palladium. These metals definitely should be recycled.
A third category of recyclables consists of parts and apparatus that can be refurbished
and reused.
Waste mining, the extraction of useful materials from wastes, provides more
materials while benefitting the environment. One of several important examples of waste
mining is the extraction of combustible methane gas, a low-polluting premium fossil
fuel, from municipal refuse landfills in which the biodegradation of organic matter in
the absence of oxygen generates the gas. Sulfur in sulfur dioxide extracted from the flue
gases generated in burning coal that contains sulfur can be reclaimed and used to make
sulfuric acid. Methods have been developed to extract aluminum from finely divided
coal fly ash generated in coal combustion. In this case, the finely divided, homogeneous,
dry nature of the fly ash is a definite advantage in processing it. It is anticipated that
growing scarcity of resources combined with the need to dispose of a variety of wastes
will lead to the development of additional waste mining processes in the future.
Diversity
Diversity in industrial ecosystems, tends to impart a robust character to them,
which means that if one part of the system is diminished, other parts will take its place
and keep the system functioning well. Many communities that have become dependent
upon one or just a few major enterprises have suffered painful economic crises when a
major employer leaves or cuts back. One area of vulnerability that has been manifested
in 2001 in California, Brazil, and some other areas is in the energy sector where
cutbacks in electricity production resulting especially from low precipitation required
for hydroelectric power have forced painful economic adjustments. In many parts of the
world, water supply from a single vulnerable source threatens diversity.
11.6. Kalundborg
Industrial ecosystems of various degrees of sophistication have existed ever since the
first industries were established, although they were not called industrial ecosystems or
even recognized as such until the latter 1980s. The system most commonly cited as a fully
developed industrial ecosystem is the one that developed spontaneously in Kalundborg,
Denmark. This system is centered around two very large energy enterprises. The first of
these is the ASNAES electrical plant fired by coal and with a capacity of 1,500 mega-
watts. The second enterprise is the Statoil petroleum refinery, processing 4–5 million
tons per year. The initial relationships in the Kalundborg system consisted of exchanges