Desalination technologies and their environmental impacts: A review

Abstract

The rapid increase in population growth and subsequent urbanization and industrialization has led to a global water demand. Hence, due to the challenges associated with accessing fresh water, desalination is increasingly being adopted to meet the global water demand. About 61% of the world's desalination capacity is made up of seawater desalination, whilst 30% is made up of brackish water desalination. Half of the world's desalination capacity is accounted for by membrane desalination, which mostly uses reverse osmosis desalination. The remaining half is primarily utilized for thermal desalination, which uses multi-stage flash distillation and multi-effect distillation. Although desalination plays an indisputable role in providing a steady supply of water in regions where freshwater resources are limited, it has diverse effects on the environment. Depending on the type of feed-water used, the desalination method employed, and how waste brine is managed, the desalination process has distinct and variable environmental consequences. The aim of this review was to provide comprehensive information on desalination technologies and their environmental impacts. To achieve this, the current global water demand and desalination production capacity were analyzed. This review contains important information for understanding and choosing environmentally friendly desalination technologies for the provision of a sustainable and environmentally friendly water supply.