Overview of the Role of Microalgae in Wastewater Management: Challenges and Opportunities.

Abstract

Microalgae-based wastewater treatment has emerged as a sustainable approach to addressing global water pollution challenges while simultaneously producing valuable biomass. This method is based mainly on the natural nutrient uptake capabilities of microalgae to remove nitrogen, phosphorus, organic pollutants, and heavy metals from various wastewater sources, including municipal, industrial, and agricultural effluents. Scientific studies and successful implementations across different regions, such as High Rate Algal Ponds in New Zealand and microalgal systems in China and the United States, demonstrate high nutrient removal efficiencies, often exceeding 90%. The treated biomass can be used in diverse ways, including biofuel production, animal feed, and fertilizers. However, several challenges such as nutrient imbalances, variability in wastewater composition, light limitations, contamination risks, and high harvesting costs, hinder widespread adoption. Technological innovations such as advanced photobioreactors, integrated treatment systems, and genetic engineering are critical for overcoming these barriers and improving the system. Public awareness and policy support will essentially facilitate broader implementation of microalgae-based systems as well as continued innovation and collaborative efforts among researchers, industry, and policymakers. Microalgae wastewater treatment holds significant promise for advancing environmental sustainability, resource recovery, and rural development on a global scale. Future research priorities includes; optimizing operational parameters, developing cost-effective harvesting techniques and conducting comprehensive life cycle assessments to evaluate environmental and economic impacts.