(86b) Macroscopic Water Integration Direct Recycle Applications Within Industrial City Plots

The development of efficient strategies for managing water usage and handling wastewater discharge in industrial zones have become imperative, as a result of the intensified environmental regulations, and the scarcity of naturally-occurring freshwater reserves. In order to assist in the design process of water systems in complex industrial regions, a macroscopic optimization-based framework for water networks within an industrial city is employed. The methodology considers direct recycling strategies for wastewater re-use amongst multiple processing facilities. The primary goal is to achieve attractive water integration schemes amongst all plants operating within a given industrial city arrangement, compared to the situation of having separate water processing systems associated with individual plants.

Targeting methods that are commonly utilized for determining minimum freshwater usage and wastewater discharge were applied to an industrial area in which several water consuming and producing processes all run in parallel. Moreover, industrial city layouts have been captured in a sense that would allow for water source-sink mapping, whilst taking into consideration service corridors, and any barriers or infeasible routing scenarios. The shortest paths that would allow effective source-sink matching amongst available water streams were all extracted using Dijkstra's Algorithm, which in turn solves a single source-to-destination shortest path problem in weighted graphs. This greatly facilitates finding optimum distances that can be used for water piping layouts and construction. In doing so, water networks that aim to achieve economical piping systems at low cost within any given industrial city arrangement can be developed, whilst managing to reduce deviations from minimum fresh and waste targets.

A case study has been carried out as a demonstration to the proposed work. A total of 6 plants were assumed to be operating within the industrial city plot, with an overall number of 6 water sources and 6 water sinks distributed amongst the individual plants. Shared freshwater and wastewater mains were assumed to and from all plants. Several cases have been investigated for single and multiple contaminant scenarios that utilize different locations for fresh and waste mains. Efficient water allocation strategies that employ shortest source-to-sink routes were obtained.