Superstructure Development, Simulation and Optimization of Desalination Systems using Aspen Custom Modeler

摘要

In this paper, Multistage Flash (MSF), Reverse Osmosis (RO) and hybrid MSF/ RO systems are modelled and simulated in Aspen Custom Modeler (ACM) V.8.4. Both steady state models include material balances; but RO focusses more on pressure differences, while MSF relies on energy balances. The model of a hybrid superstructure is developed by combining individual models of MSF and RO systems. The hybrid superstructure is developed in an optimization framework to analyse and optimize various process configurations. Operating conditions such as temperatures, pressures and process design variables such as the number of membrane elements in a pressure vessel and the number of stages in an MSF system are used as optimization variables to minimise the economic objective function. Primary results show that the hybrid MSF/ RO systems sharing common intake-outfall facilities have lower annual intake cost and can be considered in the areas where high overall product recovery and high product quality is required.