Page 223 - Sustainability in the process industry

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designer to retrofit existing equipment and revamp HENs to yield
optimum performance; and (3) identifies cleaning incentives and
predicts future performance.
9.3.7 SuperTarget

SuperTarget is mainly used to improve Heat Integration in new
design and retrofit projects by reducing operating costs and optimally
targeting capital investment (Linnhoff March, 2009). SuperTarget is
also a tool for day-to-day application by novice or occasional users,
and it makes Pinch Analysis a routine part of process design. The
software features an intuitive user interface that makes the technology
accessible to users at all levels of expertise, and advanced tools are
available for expert applications. Many of the most time-consuming
tasks traditionally associated with Pinch Analysis have been partially
or fully automated.
SuperTarget takes data directly from most popular process
simulation programs through interfaces to Aspen Plus, HYSYS, and
PRO/II. Its automatic data extraction system converts raw process
data into Pinch data, although the user has the option of overriding
the extraction defaults. SuperTarget consists of three program
modules: (1) Process is the core program, which is used to optimize
energy use within a single process unit; (2) Column performs a
thermal analysis of the heat distribution in distillation columns; and
(3) Site is used to establish heat and power targets across a Total Site.

9.3.8 Spreadsheet-Based Tools
Pinch Analysis provides a comprehensive and systematic approach to
maximizing the plant energy efficiency and minimizing the use of
utilities. The Pinch technique is amenable to use with commercial
spreadsheets, which display a grid of rows and columns made up of
multiple cells, each containing alphanumeric text or numeric values.
Kemp (2007) developed an Excel spreadsheet for Pinch Analysis that
incorporates targeting calculations and plots (see Figure 9.6). The main
components of this spreadsheet are: (1) input of stream data; (2) calcu-
lation of Composite Curves (CCs), the problem table, energy targets, and
the Pinch temperature; (3) plots of CCs and the GCC; (4) plots of the
stream population over the temperature range of the problem and the
basic grid diagram; and (5) tables and graphs of the variation in energy
and Pinch temperature over a range of ΔT values.
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Neither area targeting nor cost targeting is included in the
spreadsheet because doing so would add considerable complexity.
Suitable data on heat exchanger coefficients is often lacking and most
plots of cost against ΔT could look fairly flat, which is not always
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the case when the appropriate cost scale is set. However, topology
can still be identified from the graphs of utility use and Pinch
temperature against ΔT (Kemp, 2007).
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