Performance of a full-scale membrane bioreactor system in treating municipal wastewater for reuse purposes.
The microbial removal efficacy of membrane bioreactor (MBR) technology in a full-scale municipal wastewater treatment plant was evaluated. Total and faecal coliforms, thermo-tolerant coliforms, Escherichia coli, enterococci, somatic coliphages, F-RNA specific bacteriophages and bacteriophages infecting Bacteroides fragilis (BFRPH) were used as bacterial and viral indicators. Reclamation and reuse of MBR effluent were considered. The average Log(10) reductions of the bacterial indicators range from 6 Log(10) for enterococci to 7 Log(10) for E. coli and faecal coliforms. The average removal of FRNA coliphages was similar to that of enterococci. Complete removal of BFRPH was observed. Log(10) reductions of somatic coliphages were significantly lower than those of all other indicators. Somatic coliphages appear to be better indicators of the microbial removal efficiency of the MBR system than faecal bacterial indicators. The quality of the MBR permeate conforms largely with the microbiological standards for urban (e.g. street cleaning, vehicle washing) and agricultural reuse.
Zanetti
Franca
F
Department of Medicine and Public Health, Division of Hygiene, University of Bologna, Via S. Giacomo, 12, 40126 Bologna, Italy.
De Luca
Giovanna
G
Sacchetti
Rossella
R
D019149:Bioreactors; D015169:Colony Count, Microbial; D008567:Membranes, Artificial; D014871:Water Microbiology; D014873:Water Pollutants
D008567:Membranes, Artificial; D014873:Water Pollutants