Superstructure Optimisation of a WaterMinimisation Network with an Embedded Multi-Contaminant Electrodialysis Model

摘要

The water-energy nexus considers the relationship between water and energy resources. The increase in environmental regulations and social pressures has made it necessary to develop processes that are conservative with respect to both these resources. This work outlines the development of an optimisation model of a water network comprised of water sources, water sinks and an electrodialysis unit for the partial purification of contaminated water. The optimisation model is based on a superstructure framework, where the objective is to minimise freshwater consumption, wastewater production, energy consumption and the operating and capital costs involved in the process integration. A comparison was done between the developed model and the more common black box model, which simplifies regeneration units to linear expressions. The results show that the black box approach can lead to inaccuracies of up to 85% in the costing of regeneration units. Furthermore, it is shown that there are significant environmental and financial benefits in the simultaneous minimisation of water and energy in water networks.