Integrating algal consortia into domestic wastewater biorefineries: Mechanisms, efficiency, and circular economy perspectives

Abstract

Urbanization is occurring on a large scale at an unprecedented pace. In this context, algal consortia represent a sustainable and environmentally friendly solution for domestic wastewater remediation. This review focuses on mixed algal consortia as a treatment approach for domestic wastewater containing organic and inorganic pollutants, including nitrogen, phosphorus, heavy metals, and other chemicals. These consortia demonstrate enhanced pollutant removal efficiencies through synergistic biosorption, bioaccumulation, and biodegradation mediated by multiple algal species. Indeed, algal biomass can be valorized in biorefineries to produce a range of resources, including biofuels, biopolymers, and organic phyco-fertilizers, thereby advancing the circular bioeconomy. Overall, this review positions algal consortia as a potentially low-cost platform that integrates wastewater remediation with bioresource recovery, promoting the transformation of urban ecosystems toward a greener, more resilient future.

Keywords

Algal consortia / Phycoremediation / Domestic wastewater / Biorefinery / Circular bioeconomy / Biosorption / Bioaccumulation / Sustainable wastewater treatment

Funding

This work was supported by grants from the University Grants Commission, India (A.M. Fellow ID: 191620246470, Dec 2019) and CSIR-HRDG (S.C. Fellow ID: 09/0028(17403)/2024-EMR-I).

Conflict of interest

The authors declare that they have no competing interests.

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