Environmental Engineering Reference
In-Depth Information
from a tomato factory where there was no pollution treatment going on.
You can see the factory wastes going directly from the production process
to the sewer, to the stacks, to the dump, and to the river.
In contrast, as I pointed out earlier, today's industrial ecologists concep-
tualize industrial waste streams from the vantage point of the material and
energy flows moving through entire industrial ecosystems.As shown in fig-
ures 1 and 2, industrial material and energy flows start with the extraction
of materials and energy from the earth and proceed through various stages
of the manufacturing process and continue through to distribution and use
by end consumers. Equally important, wastes are generated at each of these
stages. These wastes move into the natural environment throughout the
industrial ecosystem from every point along the continuum from produc-
tion to consumption—not just from the end of a factory's water effluent
pipe or smokestack.
This systems perspective makes it possible for today's environmental
managers to think about pollution control in highly innovative ways.
Instead of thinking of pollution control as an end-of-pipe problem at a par-
ticular factory, they seek creative ways to minimize wastes across industrial
supply chains. Taking their cue from nature, they also seek to apply the
closed-loop model of biological ecosystems to the problem of managing
industrial waste.
What does this mean? It means a great deal. For example, I teach students
in my MBA course that we have to get away from thinking about waste
management at the plant level and start thinking about it at a systems level.
The operant industrial ecology metaphor is that of the closed-loop biolog-
ical ecosystem in which bacteria decompose the wastes of living organisms,
drawing nutrition from these wastes and returning nutrients bound up in
the organisms' excreta and dead bodies back to the soil, where they can be
absorbed again by other living organisms. Industrial ecologists urge man-
agers to find ways to turn their wastes into materials that can be utilized in
production elsewhere in an industrial system.
The classic example of this idea is “industrial symbiosis,” or waste
exchange, developed in Denmark starting in the 1970s. Figure 9 is a
schematic diagram of the Kalundborg industrial symbiosis. The most
important players are Denmark's largest electric power plant, the Asnaes
Power station; Denmark's largest oil refinery, the Statoil Refinery; a multi-
national biotech plant, Novo Nordisk; a large plasterboard factory, Gyproc;
