A mathematical programming model is proposed in this paper for determining
the optimal water usage and treatment network (WUTN) in any chemical plant,
which features the least amount of fresh water consumption and/or minimum
wastewater treatment capacity. In particular, because design equations of a
ll wastewater treatment facilities and all units which utilize either proce
ss or utility water are included in the model, more comprehensive integrati
on on a plant-wide scale can be achieved. In comparison with the available
technologies, the proposed method is more reliable, more accurate, and much
faster in synthesizing the WUTNs. Furthermore, more cost-efficient alterna
tives may be identified in certain design cases.