From the Conventional Biological Wastewater Treatment to Hybrid Processes, the Evaluation of Organic Micropollutant Removal: A Review

Because of the recalcitrance of some micropollutants to conventional wastewater treatment systems, the occurrence of organic micropollutants in water has become a worldwide issue, and an increasing environmental concern. Their biodegradation during wastewater treatments could be an interesting and low cost alternative to conventional physical and chemical processes. This paper provides a review of the organic micropollutants removal efficiency from wastewaters. It analyses different biological processes, from conventional ones, to new hybrid ones. Micropollutant removals appear to be compound- and process- dependent, for all investigated processes. The influence of the main physico-chemical parameters is discussed, as well as the removal efficiency of different microorganisms such as bacteria or white rot fungi, and the role of their specific enzymes. Even though some hybrid processes show promising micropollutant removals, further studies are needed to optimize these water treatment processes, in particular in terms of technical and economical competitiveness.