Environmental Engineering Reference
In-Depth Information
FIGURE 7
Trickling filters at Dow Chemical Plant in Midland, Michigan. (reprinted with permis-
sion from
Industrial & Engineering Chemistry
39, © 1947 American Chemical Society)
and millions of cubic feet of vented air. During the 1920s, the 1930s, and
the 1940s, Dow developed a state-of-the-art system for treating phenols in
this wastewater stream, largely in an effort to stave off regulation. (Phenolic
waste interested regulators because it gave water a foul taste and color.) The
treatment facility included a 30-acre, 45-million-gallon settling pond, a bio-
logical oxidation clarifier, four trickling filters, an activated sludge plant
where the phenolic wastes were further oxidized, and 50 acres of effluent
ponds.
12
Clearly, then, industrial and sanitary engineers began developing tech-
nologies for managing industrial air and water pollution—and managers
invested in installing them—long before the 1970s.There is a history to the
management of industrial pollution control of which most people are
unaware.
Significantly, however, early-twentieth-century engineers had a very dif-
ferent way of thinking about what they were doing than today's industrial
ecologists.They focused on dealing with industrial air and water pollution
at the level of the individual manufacturing plant, primarily through the
development and installation of end-of-pipe pollution-abatement and
treatment technologies. Their focus on the factory is evident in industrial
waste flow diagrams drawn in the 1930s and the 1940s to describe the pol-
lution control technologies they developed. Figure 8 depicts the waste flow
