A multi-objective mathematical programming framework for a sustainability analysis of wastewater treatment processes

Industrial processes are gradually becoming more efficient as new designs consider the effect on costs and environmental impacts and costs. However, decisions on operating costs might not always be in hand with lower environmental impacts. Therefore, innovative approaches are needed to better understand and recognise the economic and environmental effects of industrial processes. This paper presents a multi-objective mathematical programming framework for a sustainability analysis of two wastewater treatment processes: pervaporation (PERV) and steam stripping (SS). The framework comprises mass and energy balances, design specifications, equipment size and utilities consumption. In addition, the framework makes use of life cycle approaches to quantify the environmental impact of the process under a holistic perspective. As a result, optimal operating conditions, at which environmental impact and treatment cost are minimised, have been identified. The multi-objective operating curves developed as part of this paper serve as a basis for decision making geared towards sustainable process designs.