Page 17 - Sustainability in the process industry

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important tool: balancing and flowsheeting simulation as a basis for
optimization. It is on this basis that an integrated approach to
optimization, Process Integration, is introduced. This approach is then
connected to optimal process synthesis and combinatorial graphs.
The important question of how to apply the Process Integration and
Optimization Technology arises and is dealt with. This is further
tackled and analyzed in the following chapters.
Chapter 2 deals with the basic outline and definitions of Process
Integration (PI). It begins with a historical and methodological
introduction, briefly reviewing refinements and extensions of PI over
its years of development. The thermodynamic roots of the Pinch
Technology and of targeting heat recovery are introduced, followed
by one of the key graphical constructions in the PI methodology:
Composite Curves (CCs) for targeting process heat recovery.
Supertargeting, or targeting for a full-fledged Heat Exchanger
Network (HEN), is the next logical step. These tools are used to assess
modifications of the Pinch idea for HEN retrofitting. Although PI
was initially based on Heat Integration, an important spin-off was
the development of integration for mass exchange and water
networks. The chapter concludes with remarks on the role of PI in
making industry sustainable.
Chapter 3 introduces the other key methodology used for
sustainable process design and synthesis: optimization. It presents a
general framework and workflow of model building and follow-up
optimization, including models that incorporate “black boxes” or
“gray boxes.” It is critical to understand both the meaning and the
mathematical formulation of optimization. Toward this end, the
following questions are answered: What is optimization? What are
the main classes of optimization problems? How are optimization
problems formulated mathematically? What are the conditions for
local or global optimality? This is followed by introducing
deterministic algorithms for solving continuous linear and nonlinear,
constrained and unconstrained, optimization problems. The most
popular optimization methods and algorithms that employ stochastic
search are also reviewed. The middle part of Chapter 3 is devoted to
model creation. It includes a detailed description of conceptual
modeling: extracting data about the operating units, identifying
network and topology data, constructing equations to represent the
processes, and finally choosing a right objective function. The last
part of this chapter discusses how to handle complexity and
nonlinearity as well as how to apply process insight when evaluating
model adequacy and precision.
Chapter 4 covers the core topic from which the development of PI
began: improving the energy efficiency of individual processes and
the PI extension into Total Sites. The chapter starts by introducing
heat exchange, heat recovery, and heat exchange matches so that
readers will be prepared for the remaining chapter content. The