Page 171 - Sustainability in the Process Industry Integration and Optimization

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targeting stage and a selection stage. The approach uses the Network
Pinch Analysis to determine whether and where enhancements
should be applied in the conceptual design. One limitation of this
technique is that heat transfer enhancement is used only for taking
the place of additional area.

6.8 Locally Integrated Energy Sectors and
Extended Total Sites

Total Site targeting has established a method for analyzing the heat
sources and sinks of multiple processes and how heat can be
transferred from one process to another via a carrying medium,
such as steam (Klemeš et al., 1997). This methodology has also been
used to demonstrate the concept of a locally integrated energy sector
for distributing heat among small-scale industrial plants and
domestic, business, and social premises while integrating renewable
energy sources (Perry, Klemeš, and Bulatov, 2008). A conceptual
overall design for an energy sector that involves both heat and power
is illustrated in Figure 6.21. In this scenario, demands for heating/
cooling and electricity in units (e.g., dwellings, offices, hospitals,
schools) can be met locally by renewable energy sources such as
wind, solar cells, heat pumps, and/or excess heat and power from
the local industry. Locally installed boilers that consume traditional
fossil-based fuels, biomass, or waste can also be used to help meet
these requirements when demand is high or other sources are
unavailable. Heating or cooling and power that is not required by
one unit can be fed to a grid system and then passed to another unit

Electricity Grid
Renewables Fossil Fuels Nuclear

Steam Gas Wind Sun Heat pump
turbine turbine
Fossil fuels
Bio-fuels Electricity
(including Steam
waste) Hot water
Cooling utility
Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6 Unit 7
Fossil fuels Fossil Fossil
fuels fuels
Bio-fuels
(including waste)
FIGURE 6.21 Locally integrated energy sector with heat and power.