MABAs can potentially be self-sufficient on gas with exchange between species.
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Attempts of zero-aeration MABA are available and can be expanded.
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Future research aspects of MABA with minimal gas input were outlined.
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Potential solutions to overcome barriers to zero-aeration MABA are needed.
Abstract
Microalgal-bacterial aggregates (MABAs) have the potential to self-sustain their gas usage. By introducing O2 from microalgae to bacteria, and supplying CO2 the opposite way, ideally the gas can be circulating within the system and no external aeration is needed if other factors, like illumination and nutrients, are not limiting the growth of each member. However, several factors including discrepancies in growth rates, metabolic inefficiencies, mass transfer resistances of gas, etc. may offset the consortium from ideal. This mini-review comprehended current research status and future directions for studying MABA for wastewater treatment, especially the niche and challenges if zero aeration is desired, including detailed discussion regarding focuses on up-to-date MABA research, prospects to expand this topic, including process parameters to be optimized, potential solutions to overcoming nutrient limitations, and enhancing gas exchanges between the microalgae and bacteria at both organism and reactor levels, to achieve MABA systems with minimal gas input.
