Research progress of microbial immobilization technology in aquaculture wastewater treatment

Background With the continuous expansion of aquaculture scale in China, the discharge of nitrogen, phosphorus and other pollutants in aquaculture wastewater has increased dramatically, resulting in increasingly serious eutrophication problems of water bodies and seriously restricting the sustainable development of the industry. Traditional wastewater treatment methods have limitations in efficiency, cost and secondary pollution, so it is urgent to develop efficient and economical treatment technologies. Microbial immobilization technology significantly improves the density, activity and system stability of functional microorganisms or microalgae by immobilizing them on carrier materials, providing new ideas for aquaculture wastewater treatment. Progress At present, the research has expanded from single bacteria and algae to mixed flora and algae-bacteria symbiosis system, which has significantly improved the removal efficiency of pollutants. Carrier materials have developed from traditional inorganic and organic carriers to new materials such as composite carriers and magnetic nanomaterials, metal-organic frameworks, and biomass-derived carriers. Immobilization methods have also evolved from traditional embedding adsorption to electrospinning, 3D printing, and biomimetic mineralization. New technologies such as mineralization have achieved precise regulation of the spatial distribution and metabolic activity of microorganisms. Outlook In the future, we should focus on the research and development of efficient functional bacteria and algae and intelligent responsive carriers, deepen the research on the symbiotic mechanism of algae and bacteria, and optimize the large-scale process. Through multi-disciplinary innovation, this technology will be promoted from laboratory research to industrial application, and a new economical, efficient and stable aquaculture wastewater treatment system will be built. Significance This technology provides a feasible path for realizing efficient purification and resource utilization of aquaculture wastewater, and has both environmental and economic benefits. Its further development, popularization and application will promote the green transformation of aquaculture, protect the water ecological environment and achieve sustainable development goals are of great significance.