Synthesis of Combined Heat and Reactive Mass-Exchange Networks CHARMEN

2 Synthesis of Combined Heat and Reactive Mass-Exchange Networks CHARMEN  

Heretofore, the presented MEN/REAMEN synthesis techniques were applicable to the cases where mass-exchange temperatures are known ahead of the synthesis task. Mass-exchange equilibrium relations are dependent upon temperature and the selection of optimal mass-exchange temperatures is an important element of design. In selecting these temperatures, there is a tradeoff between cost of MSAs and cost of heating/cooling utilities. 

2 Combined heat- and reactive mass-exchange networks CHARMEN  

The CHARMEN synthesis problem can be stated as follows Given a number Nr of waste (rich) streams and a number Ns of lean streams (frtiysical and reactive MSAs), it is desired to synthesize a cost-effective network of physical and/or reactive mass exchangers which can preferentially transfer certain undesirable species from the waste streams to the MSAs. Given also are the flowrate of each waste stream, G,, its supply (inlet) composition, yf, and target (outlet) composition, y/, and the supply and target compositions, Xj and jc for each MSA. In addition, available for service are hot and cold streams (process streams as weU as utilities) that can be used to optimize the mass-exchange temperatures. 

Due to the interaction of mass and heat in the CHARMEN, one should synthesize the MEN and the HEN simultaneously. This section presents an optimization based method for the synthesis of CHARMEN s . Two key assumptions are invoked  

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