Solar concentration for green environmental remediation opportunity— international review: advances, constraints and their practice in wastewater treatment

ABSTRACT

Virtually water and energy security are major issues of modern societies. Massive amounts of industrial effluents are generated that include toxic and emerging contaminants. These compounds could be harmful to the ecosystem, if they are present at levels above the biological tolerance, and their control remains a significant issue. Compendium efforts have been demonstrated to tackle this waste to achieve a sustainable environment. However, conventional wastewater treatments are energy-intensive processes that depend on traditional energy forms. In this regards, advanced oxidation processes (AOPs) have gained interest in the modern era as they provide a viable wastewater remediation alternative. Utilisation of solar-driven AOPs ‘solar photocatalysis’ is a potentially sustainable option for the world’s water and energy scarcity issues. Based on the undertaken literature, this detailed review focuses on the utilisation of AOPs involving the use of natural and artificial energy sources in homogeneous and heterogeneous systems. The paper summarises most recent research based on AOPs with a focus on solar-related wastewater remediation. By collecting data and analysing performance from recent studies, the advances and challenges on solar energy application approaching photo-reactors operational characteristics are demonstrated and the treatment feasibility is also assessed and compared. Different types of solar concentrators for solar photochemical processes installed in wastewater treatment are described in detail. The high availability of solar energy would make the implementation of AOPs sufficient for real applicability especially in the developing countries, hence contributing to a cost-efficient and sustainable treatment. Future prospects regarding the sustainable wastewater development option with a multipronged approach are reviewed.

KEYWORDS:

• Wastewater treatment
• solar radiation
• solar reactor
• advanced oxidation processes
• photocatalysis

Disclosure statement

The author declares that there is no conflict of interest.