Scaling flowsheet optimization

At the process level, efficient flowsheet optimization strategies based on lumped parameter models are now widely used in practice (Biegler et al., 1997). At this scale, the PEFC is embedded within a power plant flowsheet model, as shown in Figure 3. The process comprises... 

However, for the practical solution of realistic, large-scale dynamic optimization problems from the field of chemical engineering, the solution methods must be tailored to the domain-specific, inherent problem structures. Also, they must be interfaced with the models generated by dynamic flowsheeting packages. In this paper, we discuss some of what is currently available, and we identify major areas for future research. 

Each chapter presents several detailed studies illustrating the application of various optimization techniques. The following matrix shows the classification of the examples with respect to specific techniques. Truly optimal design of process plants cannot be performed by considering each unit operation separately. Hence, in Chapter 15 we discuss the optimization of large-scale plants, including those represented by flowsheet simulators. 

In 2001, the SRS announced its choice of CSSX as the baseline cesium-removal technology over small-tank precipitation (a small-scale version of the ITP process) and ion exchange with CST for its Salt Waste Processing Facility (SWPF) to go into operation in 2010 [22], An optimized solvent system, model, and flowsheet were developed and demonstrated in 2001 and 2002 [37,49], and a modular concept was developed by ORNL in 2003 [68], Thus, the past decade has seen the emergence and maturation of a powerful new technology based on a macrocyclic cation receptor designed to function in solvent extraction to meet the critical need of the USDOE for a means of cleanly separating Cs from alkaline tank waste. 

The goal of conceptual process engineering is to develop a skeletal scheme for a material-making facility, as may be represented by a flowsheet, to implement the chemical conversion of available raw materials into desired product materials, fit for use, at the desired scale, safely, responsibly, economically, and on time. This flowsheet will be refined and optimized in subsequent basic and detailed engineering stages of the innovation process on the basis of additional experimental information, detailed calculations, standards, expert opinion, available equipment and construction capabilities, and other input. It is most desirable that this initial conceptual process scheme prove to be a better starting point for the remainder of the innovation process than other possible flowsheets. A flowsheet does not exist until it has been first synthesized. 

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