Abstract
Most of the previous industrial water network models use freshwater as a vital water supply source without defining the origin of freshwater. However, in practice, the freshwater can be obtained from many water resources (e.g., municipal water, groundwater, surface water, municipally treated water, and seawater), after necessary Pre-treatment. Also, the effluents from the desalted water station, power station, and cooling water station can be used in other water using processes by satisfying the contaminant limits. Nevertheless, the existing water system design model does not apply directly to the design of effective industrial water systems. In order to overcome the above limitation, this paper proposed an innovative property based mathematical superstructure model for the industrial water network, consisting of water pre-treatment, water utility, water-using, and wastewater treatment systems. The proposed mathematical model provides appropriate water resource selection to acquire freshwater for the industrial water network and integrates all possible functional designs for water treatment, reuse, and recycling. The design model comprises the related equations, flow rate, and property constraints between the different water sources and sinks. The proposed model is framed as a nonlinear programming (NLP) algorithm and resolved using commercial software GAMS. The proposed model is validated by a case study of the simplified water system of the Chinese industrial chemical complex. Results show a substantial reduction of 8.39 % and 21.75 % in the total annualised cost and freshwater demand.
