A Study on Life Cycle Impact Assessment of Seawater Desalination Systems: Seawater Reverse Osmosis Integrated with Bipolar-Membrane-Enhanced Electro-Dialysis Process

Abstract

A lot of research has been carried out to improve the sustainability of seawater desalination. Despite progress, relatively few studies have analyzed the sustainability of seawater desalination processes integrated on two fronts, i.e., (i) process integration and (ii) energy integration. In addition, life cycle assessment studies on multi-stage flash (MSF) desalination often neglect the impact of the disposed brine by assuming that dilution of the discharged brine impacts on ecological systems less. The present study contributes to these omissions by exploring the environmental sustainability of seawater desalination systems using life cycle impact assessment (LCIA). More specifically, the LCIA of Seawater Reverse Osmosis (SWRO) integrated with (i) an Electro-Dialysis (EDBMED) process and (ii) solar photovoltaics (PV) is investigated. Life cycle analysis was used to identify pertinent indicators of the LCIA and their implications in SWRO. The comparative analysis reveals that the advantage of SWRO as compared to other technologies such as MSF is energy efficiency, at estimated levels of 75.0%. The study concludes that despite the technological challenges associated with sustainable desalination and sustainable brine management, integrating renewable energy into seawater desalination can contribute to the sustainability improvements of seawater desalination systems. The findings of this paper provide an initial assessment of the ecological footprints of seawater desalination systems.