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Encyclopedia of Physical Science and Technology EN012I-591 July 26, 2001 15:54

594 Pollution Prevention from Chemical Processes

The traditional approach to process design has been in describing their approach to the environment. The shift
to first engineer the process and then to engineer the from 20–50 years of conventional pollution control to a
treatment and disposal of waste streams. However, with preventative approach was dramatic because of the rever-
increasing regulatory and societal pressures to eliminate sal in priorities.
emissions to the environment, disposal and treatment costs The adoption of pollution prevention as a clearly differ-
have escalated exponentially. As a result, capital invest- entiated approach to environmental improvement began
ment and operating costs for disposal and treatment have in U.S. industry and policy during the late 1970s. While
become a larger fraction of the total cost of any manu- examples of improved efficiency and hence less waste had
facturing process. For this reason, the total system must existed since the start of the Industrial Revolution, the dis-
now be analyzed simultaneously (process plus treatment) tinct explosion of successes in pollution prevention did not
to find the best economic option. occur until the mid-1980s. Figure 1 shows an approximate
Experience in all industries teaches that processes time line of this period.
which minimize waste generation at the source are the The early creation at the 3M Corporation of money-
most economical. For existing plants, the problem is even saving innovations that reduced chemical losses to air,
more acute. Even so, experience has shown that waste gen- water, or land was widely publicized. However, propaga-
eration in existing facilities can be significantly reduced tion into other large corporations was almost nonexistent.
(greater than 30% on average), while at the same time The efforts through university research and state programs
reducing operating costs and new capital investment. (beginning in North Carolina) to illustrate the benefits of
In this article, we present a broad overview of the path pollution prevention, and a steady presentation of princi-
to an effective pollution prevention program. The phases ples such as the creation of the pollution prevention hierar-
and individual steps of this proven methodology are ap- chy and roadmaps, extended over the early to mid-1980s.
plicable to both large-scale and small-scale problems. The In 1986–1988, the improved information regarding chem-
focus of the methodology is on identifying pollution pre- ical losses to the environment as a part of the U.S. EPA
vention engineering technologies and practices that will Toxic Release Inventory (TRI) Program precipitated ac-
change what is happening inside the pipes and vessels tion. A number of CEOs of large corporations challenged
of the manufacturing process, rather than just on simple their companies, in a very public fashion, to reduce these
procedural or cosmetic changes. In fact, many of the tech- chemical losses. As the autocatalytic effect spread to other
niques and tools that support the methodology can be eas-
ily applied by chemists, process engineers, and project
engineers to individual waste streams within a process
or facility. For example, the methodology has been and
continues to be successfully practiced inside the DuPont
Company. We present a list of pollution prevention en-
gineering technologies and practices that nicely comple-
ments the methodology and provides a useful knowledge
base for quickly identifying possible process changes that
reduce waste generation and emissions.

II. HISTORY OF POLLUTION PREVENTION

No single dimension of the solutions for environmental
problems has captured the imagination of engineers, sci-
entists, policy-makers, and the public like pollution pre-
vention. In the space of two decades (1980–2000), the
philosophical shift and the record of accomplishment has
made pollution prevention a fundamental means for envi-
ronmental management. This effort actually began during
1976–1980 when 3M Corporation initiated the 3P pro-
gram and North Carolina adopted waste minimization as
a state-wide priority for managing emissions from indus-
try. By 1990, virtually all of the Fortune 1000 U.S. cor- FIGURE 1 General historical sequence for growth of cleaner
porations had pollution prevention as the first emphasis technology in United States.