Mass exchange networks optimization approach

Another problem of significance is the optimum policy of water recycling. This subject is in itself substantial and cannot be handled here. An economical approach involves optimal allocation of streams, both as flow rates and contaminant concentration. The analysis may be performed systematically with tools based on the concept of water pinch and mass-exchange networks . This subject is treated thoroughly in specialized works, as in the books of El-Halwagi [19] and Smith [20]. A source-sink mapping technique developed around the acrylonitrile plant may be found in the book of Allen and Shoppard [21]. 

Kirthick, R., Kumaraprasad, G. and Sruti, B. (2010) Hybrid optimization approach for water allocation and mass exchange network. Resources, Conservation and Recycling, 54 (11), 783—792. 

This paper has presented and tested a design philosophy for the synthesis of mass exchange networks whereby an MINLP approach is integrated with pinch analysis tools. At the heart of the integration is the use of pinch-based total cost targets to evaluate the optimality of MINLP solutions and driving force diagrams to identify different initial solution structures. 

The approach followed in the remainder of this chapter consists of establishing an algorithm for designing a heat- (mass-) exchanger network that consumes the minimum amount of utilities and requires the mininium number of exchangers (MUMNE). Although this network may not be optimal in an economic sense, it does represent a feasible solution and will often be close to the optimum... 

Synthesis of subsystems. The main objective of this approach so far has been the reduction and optimization of energy, including thermal pinch, distillation sequences, and mass and heat exchange networks, which will be described in a Httle more detail later in the chapter (In addition, see chapter 4). 

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