(521a) Synthesis of Sustainable Property-BASED WATER Networks
This work presents a new mathematical programming model for the optimal synthesis of recycle and reuse water networks considering simultaneously the integration of the water network inside the industrial facilities and the surrounding watershed to satisfy process and environmental constraints. The model considers the optimal location of the new industrial facility to integrate its wastewater discharge to the environment with the surrounding watershed through a disjunctive formulation; therefore, the model was formulated to predict the behavior of the watershed impacted for the new polluted discharges, in this regard, the material flow analysis (MFA) technique was used. Besides, the mass integration and the model to simulate the watershed behavior are carried out based on the properties that impact the process because for wastewater streams is very difficult to characterize them in terms of the composition due to the several components contained, considering all inlet and outlet streams in the watershed (i.e., residential, sanitary, industrial discharges and extractions), therefore, when the new industrial plant discharges its wastewater to the environment, the properties are tracked throughout the watershed and the surroundings. Also, there are natural phenomena that affect the properties of the watershed (i.e., evaporation, filtration, etc), as well as, it is important to consider the effect of the chemical reactions carried out in the rivers over the properties considered. Finally, the objective function consists in minimizing the total annual cost that is constituted by the installation of the new plant cost (including the transportation for raw materials, products and services, as well as the land cost), the wastewater treatment costs (including the piping cost) and the fresh sources cost. The MINLP model was implemented in the software GAMS where the solver DICOPT was used. The proposed model was applied to a two cases of study (one in Mexico and the other one in Egypt), and the results show that the proposed approach can be very useful to reduce the environmental effects when the in-plant mass integration and the surrounding watershed are considered simultaneously.