Synthesis of Total Water Networks for Batch Processes Considering the Impact of Contaminants

This article develops a systematic methodology to consider the impacts of contaminants on regeneration network when synthesizing the integrated water network for batch processes. The method is based on the improved state-space superstructure where full configurations of the network are incorporated and concentrate streams of two outflows regeneration modules can be reused and further purified. To bridge the gap to industrial applications, regeneration modules with variable removal efficiencies for different types of contaminants and the inhibitory impact of toxic substances on regeneration network are considered. On these basis, an overall mixed-integer nonlinear programming (MINLP) model is formulated. The results of the case study show that the further reuse of concentrate streams decreases the fresh water consumption and cost- optimal network can be achieved when considering the effects of contaminants. In addition, the toxic substances in wastewater for regeneration also lead to the integration of different regeneration technologies.