Optimization of water network integrated with process models

In this paper, a novel approach for the synthesis of water network incorporated with process models is introduced. The process models are utilized to relate the variables (i.e., flow rate and concentration) of process output (typically defined as internal water source) with those of process input (i.e., water sink). A generalized water network superstructure is developed to embed all possible process units and all the connections among resources, interceptors, process units, and wastes. The problem is formulated as four optimization problems (minimum freshwater flow rate, intercepted flow rate, intercepted mass load, and number of connections), and the four models are solved in sequence to locate the targets. A literature case is used to validate the proposed approach. Moreover, a sour water network of a practical refinery plant is presented to illustrate the applicability and effectiveness of the proposed approach.