Conceptualising a Model to Assess the Optimum Water Flow of Industrial Symbiosis (IS)

Industrial Symbiosis (IS) has obtained worldwide concern as a new initiative for achieving collaborative benefits through the exchange of resources including water among industries. Even though these initiatives became prominent as successful projects in the early stages, many of them have resulted in failures in the long term due to the absence of the prior evaluation and optimisation of identified water synergies in IS planning. Further, the main attention has been given to achieving cost reductions in individual plants rather than analysing the environmental benefits of IS networks that can be achieved through the maximum recovery of wastewater. The existing evaluation emphasises the need to have a standardised way to assess the optimum water flow of IS. Thus, the purpose is to conceptualise a model to assess the optimum water flow of IS based on secondary data analysis. A desk study and a detailed literature review were selected as suitable methods for reviewing the existing literature relating to water exchange in IS networks, water input and output flow, and optimisation methodologies. As the key findings derived through analysis, water inputs and outputs, a boundary for the selection of industrial entities, typical water synergies, and optimisation formulas were established. Finally, a conceptual model was developed to assess the optimum water flow of IS, which was evaluated through expert interviews to identify further improvements. The developed model forms a unique foundation for assessing the optimum water flow of IS, applying in any context subject to context-specific enhancements. Most importantly, the novelty can be highlighted as the consideration given to maximum wastewater recovery in achieving the reduction in the freshwater utilisation of industrial entities within the IS network. Nevertheless, this conceptual model is still at its early development stage, and it is subjected to more empirical testing and research for its practicality and further refinement as a way forward for the research.