Page 125 - Materials Chemistry, Second Edition

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Sustainable Industrial Design and Waste Management
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• In 1989, Novo Nordisk switched from Lake Tisso to well water.
• In 1989 Asnaes power station started fish farming to solve the prob-
lem of thermal pollution. The sea water used to cool the condenser
of the thermal power plant was utilized to develop an artificial fish
farm that makes the fish grow faster in such a warm temperature.
– Driving force: Economic benefits.
• In 1990, Statoil began selling molten sulfur to Kemira in Jutland.
Excess gas from the operations at the Statoil refinery was treated to
remove sulfur, which was sold as raw material for the manufactur-
ing of sulfuric acid at Kemira, and the clean gas was then supplied to
Asnaes power station and to Gyproc as an energy source.
– Driving force: Economic benefits.
• In 1991, Statoil sent treated wastewater to Asnaes for utility use.
Due to community pressure as well as related regulations, Statoil
invested in a wastewater biological treatment plant to supply clean
water to Asnaes.
– Driving force: Enforcing regulation and economic benefits.
• In 1992, Statoil sent desulfurized waste gas to Asnaes.
• In 1993, Asnaes supplied gypsum to Gyproc. Asnaes power station
installed a desulfurization unit to remove sulfur from its flue gases,
which allowed it to produce calcium sulfate (gypsum). This is the
main raw material in the manufacture of plasterboard at Gyproc. By
purchasing synthetic “waste” gypsum from Asnaes power station,
Gyproc were able to replace the natural gypsum imported from Spain.
– Driving force: Enforcing regulation and economic benefits.

In summary, materials and energy are being exchanged in the city of Kalundborg
among different companies and with the community in a closed loop such
that the waste or byproduct of one company is taken as the raw material for
another. It all started in 1961 with the need to use the surface water from
Lake Tisso for a new oil refinery (Statoil) to save groundwater. Originally,
there was no planning of the overall network; it just evolved as a collection
of one-on-one deals between different industries that resulted in economic
benefits for both partners in each deal. Figures 3.1 to 3.3 illustrate the net-
work of companies in the symbiosis, showing the extent of the material and
energy exchanges.

Material and energy flow analysis
Material and energy exchanges and savings started in Kalundborg in 1961 as
the Statoil refinery began using water from Lake Tisso instead of ground-
water, saving around 2 million cubic meters of water per year. Then Gyproc
located its facility in Kalundborg to take advantage of the fuel gas available
from Statoil. By the early 1970s, Statoil refinery agreed to provide its excess
gas (byproduct) to Gyproc instead of burning it, which has been considered by
Gyproc to be a source of low cost fuel. Later on as Statoil supplied both its