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UNIT 4: ENVIRONMENT MANAGEMENT SYSTEMS
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photosynthesis plants produce carbohydrates. These feed herbivores,
which then fall prey to carnivores, whose waste is, in turn, food for
detritus organisms. Similarly, industries could reuse waste as raw
material and reuse or recycle end products after they have been
consumed. In this way materials and waste would move round in
closed circuits.
• Ecosystems have built-in methods for optimising the use of materials
and energy. Similarly, dematerialisation is about doing more with less:
optimising the use of raw materials and extending the service life of
end products. An additional benefit in extending service life is that it
creates new job opportunities, especially in maintenance and repair.
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Industrial Ecology in Practice
One of the best examples of industrial ecology in practice is the case of the
Danish town Kalundborg.
Kalundborg has four main industries:
• Asnaes Power Station, a coal-fired plant;
• Novo Nordisk, producing enzymes and pharmaceuticals;
• Gyproc, a plasterboard manufacturer;
• Statoil, an oil refinery.
The evolving industrial ecosystem works as follows:
• Asnaes produces steam and heat while generating electricity, and
sends some of its steam to Statoil and Novo Nordisk. Statoil, which
gets 40% of its steam requirements from Asnaes, uses the steam to
heat pipes and tanks. Novo Nordisk gets 100% of the steam it needs
from Asnaes, and uses it as a source of heat and pressure.
• Asnaes also pipes excess heat to local fish farms and some homes.
Plans are underway to expand this to all homes in Kalundborg by 2005.
This process of heat and steam recycling has raised the efficiency of
coal burning from 40% to over 90%.
• Asnaes’ waste steam and the by-product gypsum (produced in the
scrubbers which reduces sulphur dioxide emissions) are used by
Gyproc to make plasterboard. The remaining gypsum is sent to local
cement producers.
• At the Statoil Refinery, flue gas is created as a by-product of oil
refining. The gas first goes through a de-sulphurisation process. The
hot, liquid sulphur captured is sold to the Kemira Acid Plant in Jutland.
Statoil’s sulphur-free flue gas goes to Asnaes and Gyproc, instead of
being burned off. Asnaes thus saves 30,000 tonnes of coal a year.
Statoil’s flue gas meets nearly 95% of Gyproc’s gas needs.
• Novo Nordisk gives its nitrogen-rich sludge to local farmers via
pipeline or truck. This is reported to save each farmer about US$50,000
a year in fertiliser costs.
• This evolving symbiotic scheme is also being extended to water use.