Promoting the Achievement of wastewater treatment by microalgae-based co-culture systems: From interactions mechanisms to pollution control performance

Abstract

Efficient wastewater treatment methods have been the focus and hotspot of research. Microalgae-based co-culture systems (MBSs) is regarded as a promising wastewater treatment technology due to its low economic cost, high pollutant removal efficiency, high biomass yield and environmental friendliness. However, the research summaries on the interaction mechanisms among microorganisms, pollutant removal mechanisms, and related influencing factors in MBSs are not sufficiently clear to achieve the scale-up development of MBSs. The review revealed that microorganisms in MBSs interact through O₂-CO₂ exchange, metabolite exchange, and production of EPS to realize symbiosis and remove pollutants from wastewater through biosorption, bioaccumulation, and biodegradation. Light conditions, temperature, and inoculum ratio are the main factors affecting the wastewater treatment performance of MBSs. In addition, MBSs can convert nutrients (particularly nitrogen, N and phosphorus, P) in wastewater into microalgal biomass, and further processed microalgal biomass can be converted into biofuel, which is a potential source of renewable energy. By analyzing the potential application of MBSs, MBSs are feasible in terms of pollutant removal, biomass production and reduction of economic costs. Prospects are presented for the challenges and future development of MBSs in order to increase the potential of MBSs for scale-up.