Advancements in high-rate algal pond technology for enhanced wastewater treatment and biomass production: A review

This review examines recent advances in high-rate algal pond (HRAP) technology for wastewater treatment and the production of microalgae-rich biomass. It highlights the latest methods developed to enhance the efficiency and sustainability of these systems. Notably, these methods include two-stage cultivation, biomass recirculation, and strategies that collectively improve algal productivity and treatment efficacy, such as the implementation of hybrid systems. Hybrid systems combine HRAPs with other wastewater treatment technologies, such as biofilm reactors. By optimizing these configurations, HRAPs demonstrate effectiveness in nutrient removal, biomass production, and harvesting, enhancing their potential as a scalable and adaptable solution for effluent treatment and biomass production. Additionally, this study reviews HRAP performance in removing emerging contaminants, an important aspect in the context of current effluent treatment. This review establishes a significant advancement in HRAP technology, promoting its adoption as a sustainable and real-scale wastewater treatment option. [Display omitted] •96 experimental results were used to discuss sanitary sewage treatment in HRAP.•Standardized designing methods should be further encouraged.•Using HRAPs as tertiary units is the recommended approach.•CO2 supply is a promising strategy to overcome the impacts of NH3 volatilization.•HRAPs have a high potential as decentralized and rural treatment units.