Page 146 - Sustainability in the Process Industry Integration and Optimization

CHAPTER 6

Further Applications of

Process Integration

rocess Integration, also called Pinch Technology, was initially
developed for energy and specifically for Heat Integration.
PDetails of the origin and development of Heat Integration were
given in Chapters 2 and 4. Its further development resulted in a
methodology for integrating mass transfer and water integration in
particular; this technology was described in Chapter 5. This chapter
(chapter 6) focuses on the additional applications and especially
recent developments that have expanded the generic Process
Integration ideas in various other directions. Given the rapid
development of this methodology, it is not possible to cover all recent
achievements. Nonetheless, this chapter explores several interesting
directions that have considerable potential for future development.

6.1 Design and Management of Hydrogen Networks
The evolution of Pinch Technology has allowed mass integration to
be extended to hydrogen management systems. In one of the earliest
works in this field, Alves (1999) proposed a Pinch approach to
targeting the minimum hydrogen utility. This method was based on
an analogy with process heat recovery. Just as the distribution of
energy resources in a plant can be analyzed and designed via using
Pinch Technology, so can the distribution of hydrogen resources be
handled in refineries, which typically have several potential sources
(each capable of producing a different amount of hydrogen) and
several hydrogen sinks (with varying requirements). However, the
designer has more flexibility in determining the hydrogen loads of
individual units by varying the throughput of units and operating
many processes over a range of conditions. As a result, there is
considerable potential for optimizing refinery performance.
A liquid hydrocarbon feed stream is mixed with hydrogen-rich
gas, heated, and then fed to a reactor. Part of the hydrogen is
consumed by reaction with the feed. Light hydrocarbon compounds
(methane, ethane, and propane), hydrogen sulfide (H S), and
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