Innovations in Microalgae-Based Wastewater Treatment and Biomass Valorization: An Integrated Circular Economy Approach

One of the main critical environmental concerns is water pollution. This is caused by various contaminants, including heavy metals, organic pollutants such as dyes, and excess nutrients, leading to adverse ecological as well as health effects. Conventional treatment strategies, such as chemical precipitation, membrane filtration, and other techniques employed are often expensive and have limitations and thus necessitating sustainable and cost-effective alternatives. Microalgal-based biosorption has gained significant attention as an eco-friendly approach for water bioremediation owing to its high efficiency in adsorbing pollutants. Moreover, in addition to wastewater treatment, the harvested microalgal biomass holds extensive potential for valorization in various industrial applications. This chapter covers the importance of microalgal-based treatment strategies to mitigate pollutants in wastewater and highlighting its biomass utilization in biofuel production, biofertilizers, and other value added products. With perspectives of cost effective strategy, this chapter provides the key role of cultivating microalgae in wastewater as a synthetic medium. This integration of microalgal-based biosorption into wastewater treatment systems aligns with sustainable development goals, reducing environmental pollution while generating bio-based products. It also covers the challenges in optimizing biosorption efficiency and large-scale implementation. Thus, microalgal biosorbents present a promising, sustainable, and circular approach for water treatment and biomass valorization, bridging the gap between pollution control and sustainability.