Optimisation of Wastewater Treatment and Recovery Solutions in Industrial Parks

A considerable amount of carbon-containing and nutrient-rich waste resources are generated globally each year, which could be converted via various routes to bioenergy and other value-added bio-products. In an industrial park setting in which multiple waste-streams of different compositions along with various treatment/recovery technologies may be present, significant opportunities for symbiotic interaction exist through appropriate coordination. To enable such a shift, this work introduces an optimisation framework suitable for handling such a problem, thus providing the potential for significant reductions in the environmental and financial costs associated with the wastewater treatment process. A superstructure is proposed whereby different waste streams of varying flow rates and compositions are input and acted on by a combination of different treatment/recovery technologies to produce a set of treated output streams. The process is captured within a Mixed-Integer Linear optimisation formulation (MILP), in which a combined set of (typically competing) objectives capturing the financial, energy and environmental considerations associated with the problem, is minimised. Variables representing design and operational decisions as well as time-varying flow rates and compositions are included, while the physical limitations of the system and the design requirements of the outputs are also captured.