Integrated process analysis and design for sustainable local resource management
Department of Engineering Science, University of Oxford, UK
Melissa Leung Pah-Hang
Centre for Environmental Strategy, University of Surrey, UK
Integration between facilities in a particular locality has been explored between industries as a way to optimize economic and physical resources, leading to lower waste generation, shared responsibility with the environment and the society. The most widely known concepts come from industrial ecology such as industrial parks and industrial symbiosis. These initiatives have primarily focused on the industrial or technological processes and how they can form symbiotic relationships and recycle loops. However, the processes in two key parts of a wider system are often dismissed: ecosystems (as ultimate resource provisioners) and consumption by the society. When considered at the local scale, these components have the potential to (and ideally they should) be included into the analysis and decision making for an efficient and sustainable management of resources. This paper reports a systems engineering approach for the integration of local processes or activities, as a way to use locally available resources (biomass, solar irradiation, water, etc.) in a more efficient manner to meet local population needs. System dynamics modelling is used to determine ecosystem constraints which are then fed into the models for water and energy integration using superstructure optimization. The tools and methods are combined into a framework to facilitate the identification of opportunities for exchange of resources between local ecosystems, production and consumption components and to analyze the performance of the resulting localised production system in respect to the level of satisfaction of the needs for food, energy and/or water.
The application of the framework will be shown in a case study for the integration of the food-water-energy nexus in the Whitehill and Bordon eco-town in the UK. The limits for the available biomass and water resources are set from a system dynamics analysis of processes in local heathlands and aquifer as the ecosystem components. Nutrient exchange occurs in the food production processes, which is in turn integrated with the water and energy processes using a superstructure optimization approach. The optimization uses the concept of cumulative exergy as unifying quantity for accounting resource consumption and it is used as the objective function to minimize. The case study shows how the integration between technological and ecological processes can be achieved through the recycling of nutrients and water within and across the various system components to keep the ecosystem functions that provide the fresh resources for the relevant production processes. The proposed framework can potentially provide guidance to practitioners and decision makers for the sustainable management of local resources.
See more of this Group/Topical: Management Division