Exergy Analysis of Membrane Desalination Systems

Abstract

The scarcity of sustainable freshwater resources has become a worldwide concern. Hence, water desalination has been a vital solution for many decades. Thermal- and membrane-based techniques are the main types of desalination adopted globally. Thermal desalination technologies require excessive amounts of thermal and electrical energy for heating, which is considered unsustainable. Subsequently, membrane-based processes are preferred, especially reverse osmosis (RO), which operates near the thermodynamic limit. However, other processes, like membrane distillation (MD) and forward osmosis (FO), still operate far from the recommended range. Accordingly, various attempts are still required in all membrane-based processes to decrease specific energy consumption (SEC) potential. Thus, an intensive thermodynamic analysis is required in terms of the exergy aspect. This chapter introduces the most investigated approaches to membrane-based desalination systems using exergy analysis, a diagnostic tool that is used to identify the most destructive components and enhance system performance. Moreover, this chapter focuses on the integration of these membrane-based approaches with other desalination systems for reducing the overall system exergy destruction, which is sure to pique the reader's interest and open up new avenues for research and development in the field.