An MILP model for optimizing water exchanges in eco-industrial parks considering water quality

- An optimization model that satisfies the conflicting EIP objectives is presented.
- Economic cost incorporates capital & operating costs of exchange infrastructures.
- Environmental impact incorporates volume & quality of water consumed and disposed.

Unlike other resources that may come in multiple energy forms, there is no substitute for freshwater. Therefore, Eco-Industrial Parks (EIPs) have been designed to encourage interplant water exchange networks in order to minimize the consumption of freshwater as well as the generation of wastewater. This study proposes a model that simultaneously minimizes the economic and the environmental objective functions of an EIP through goal programming. The economic costs considered integrates the necessary piping and operating costs together with the freshwater, wastewater, and treatment costs, while the environmental impact considered the volume and the quality of the water used and released by the EIP. Results showed that the considering water volume and quality in minimizing the environmental impact gave better results than considering water volume only. Economic costs and environmental impacts were also found to be dependent on the priorities given to each goal, as well as the treatment quality of the processes.