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ENVIRONMENT AND ENERGY
The extent and nature
of industrial wastewater
production (Part 2)
In the previous issue, we described the extent and nature of industrial
wastewater production, highlighting the opportunities from the use and
recycling of wastewater, as well as the recovery of energy and useful
by-products when addressing natural resource challenges in the context of
sustainable industrial development. This is the second part of that report.
Extracted from United Nations World Development Report
INDUSTRIAL SYMBIOSIS
One notable opportunity for industrial wastewater use
and recycling is the cooperation between plants in
industrial symbiosis (SSWM, n.d.). This can involve the
exchange of process water or the recycling of treated
wastewater for purposes similar to in-plant recycling.
Examples include steam or hot wastewater, or
wastewater that contains organic material and
nutrients, and unconverted raw materials that may be
economic to recover: oil, used solvents, starch and other
substances that can be traded or recycled, perhaps by
employing waste registers between adjacent industries
(WWAP, 2006). The treatment technology options are
similar to those for in-plant purposes and may employ
decentralised systems.
These may involve a dedicated centralised wastewater
treatment plant that services all the industries.
ECO-INDUSTRIAL PARKS
Industrial symbiosis is best seen in eco-industrial parks
which strategically locate industries adjacent to one
another to take convenient advantage of wastewater
management and recycling.
January 2019 Volume 25 I Number 1
For SMEs, this can be a significant way to save
on wastewater treatment costs. Important factors
are the sharing of information to match needs,
reasonable proximity, and reliability of supply in
terms of quantity and quality. Combined Heat and
Power Plants (CHP, or cogeneration), which require
substantially less cooling water than conventional
generation, are more efficient when they are located
near to the demand for heat and power such as
an industrial complex and as decentralised power
supply (Rodríguez et al., 2013).
Interesting examples of eco-industrial parks are found
in many countries, for example the Shanghai Chemical
Industrial Park in China (WWAP, 2015). The Kalundborg
Industrial Symbiosis is an ‘industrial ecosystem’ where
the by-products of one enterprise are used as a resource
by other enterprises, in a closed cycle.
It began in 1961 with the development of a new project
to use surface water from Lake Tissø for a new oil
refinery with the aim of saving the limited supplies of
groundwater. The City of Kalundborg was in charge of
building the pipeline while the refinery was responsible
for the financing.
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