Seafood industry effluents: Environmental hazards, treatment and resource recovery

Global demand for fresh water is rising at a rapid rate and is struggling to keep pace with water requirements of increasing population. Against this scenario, the seafood industry including aquaculture routinely uses voluminous amounts of fresh water and discharges large volumes of post-process wastewater as effluents. The presence of proteins, oil, carotenoids, minerals, and other compounds in the effluents make them high in biological oxygen demand and chemical oxygen demand, and hence, responsible for significant environmental hazards. Therefore, appropriate treatments of the effluents are essential before they are discharged or disposed off to mitigate the environmental problems. Besides, there are good potentials to recover various ingredients from the effluents for uses as food additives, nutraceuticals, nutritional supplements, flavoring agents, fertilizers, plant bio-stimulants, animal and aqua feed. Recent developments in microbial technology, particularly, algal biotechnology has potentials for cost-effective and eco-friendly treatments of the effluents together with the recovery of various biomolecules. Cultivation of microalgae in the effluents provide single cell proteins (SCP) that can have applications as animal feed including feed for the rising aquaculture industry. The SCP is also sources of proteins, oils, carotenoids and other compounds. The rich contents of oil in SCP can be resource for biofuel. In addition, the treated wastewaters can also be used as fertilizer. Recent developments in effluent treatments have potentials to improve water security, protect the environment, support food and nutraceutical industries, and enhance seafood sustainability, thereby contributing an interesting value chain for a circular bioeconomy.

Automated summary

Global demand for fresh water is increasing rapidly, and the seafood industry's wastewater treatment and resource recovery are crucial for environmental impact and sustainability.