Page 304 - Sustainability in the Process Industry Integration and Optimization

CHAPTER 12

Typical Pitfalls and

How to Avoid Them

rocess Integration (PI) has proven to be a powerful optimization
tool for designing processes that are energy-efficient,
Penvironmentally friendly, and sustainable. The methodology
provides clear insight into the design process, but this direct
simplicity is sometimes misunderstood by potential users. Once
proper data are made available, the procedure generates an excellent
lead for the design process. But just as with all optimization tools,
potential pitfalls when using PI include improper formulation of the
problem and incorrect data extraction.
Even when the most efficient and well-developed methodology
is used to solve an optimization problem with high precision, the
results may be suspicious unless we have been solving the right
problem. In other words, has the problem been formulated in a way
that closely reflects the real process under consideration and
(especially) has the correct data been extracted? Negative answers to
these questions explain such published statements as: “Pinch
technology [or process integration] did not work for this problem.”
When these problems are revisited it usually becomes obvious that
the PI methodology is not at fault; rather, an inexperienced or
overconfident user is typically the cause.
Therefore, this chapter is devoted to various mistakes that a
designer might unwittingly make. The most basic issue concerns
how one starts a PI-based project and how it is run. Kemp (2007)
summarized the key steps listed below, which have been further
developed based on the authors’ experience. These steps are
specifically related to Heat Integration; however, they apply with
only small adjustments to mass, water, and other integration as
well.

1. Become familiar with the analyzed process. The most efficient
way is to closely liaise with the process designer and/or plant
manager, especially if the plant is already operating.

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