The role of physical-chemical treatment in wastewater reclamation and reuse

Amid the heightened public health concerns for emerging microorganisms such as cryptosporidium and enteropathogenic E. coli in the water environment, there have been many instances where optimization of chemical coagulation-flocculation processes and filtration of wastewater was not achieved in practice, resulting in waste of coagulant chemicals and breach of the multiple barriers to pathogen removal and inactivation; thus, unnecessarily endangering public health. In addition, lack of information on the optimization of these processes has hampered the establishment of alternative and more cost-effective wastewater reclamation methods for tertiary and advanced wastewater treatment. Thus, the purpose of this paper is to evaluate the basic factors affecting the optimization of chemical coagulation-flocculation and filtration processes in municipal wastewater reclamation and reuse, based on the theoretical developments and practical applications. Reference is also made to the wastewater treatment processes and operations that can produce reclaimed water with an extremely small probability of enteric virus contamination.