Optimal design of multicomponent VOC condensation systems

Abstract

The objective of this work is to address the problem of optimally selecting and designing condensation systems for the recovery of volatile organic compounds (VOCs) from gaseous emissions. In a typical VOC condensation system, numerous refrigerants may be technically feasible for achieving the desired VOC recovery. The task of selecting the most economical refrigeration system is a challenging one. All potentially appli- cable refrigerants ought to be simultaneously screened so as to select the best separation system. Such an optimal system may be a hybrid process which includes more than one refrigeration unit. This paper presents a systematic design technique for optimizing the selection of refrigeration systems for gaseous emissions with multiple VOCs. The technique developed involves a three-stage targeting approach. The first stage identifies a VOC condensation network which possesses the minimum annual operating cost. The second stage involves the minimization of the fixed cost of the refrigeration units so as to achieve the minimum operation cost determined in stage one. Stage three entails the determination of the final refrigeration network, whereby tradeoffs between operating and fixed costs are considered. A case study covering the recovery of multiple VOCs from the gaseous emission of a magnetic tape manufacturing plant will be solved using the design methodology.