Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | OPTIMAL SLUDGE RETENTION TIME FOR A BENCH SCALE MBR TREATING MUNICIPAL SEWAGE |
| Abstract | Membrane bioreactors allow for higher sludge concentrations and improved degradation efficiencies with respect to conventional activated sludge. However, in the current practice these systems are often operated under sub-optimal conditions, since so far no precise indications have yet been issued on the optimal operating conditions of MBR for municipal wastewater treatment. This paper reports some results of four years of operation of a bench scale membrane bioreactor where steady state conditions were investigated under different sludge retention times. The whole experimental campaign was oriented towards the investigation of optimal process conditions in terms of COD removal and nitrification, biomass activity and growth, and sludge characteristics. The membrane bioreactor treated real municipal sewage, and four different sludge ages were tested ( 20, 40, 60, and 80 days) and compared with previous data on complete sludge retention. The results showed that the the biology of the system, as assessed by the oxygen uptake rate, is less affected than the sludge physical parameters. In particular, although the growth yield was observed to dramatically drop for SRT higher than 80 days, the biological activity was maintained under all the tested conditions. These considerations suggest that high SRT are convenient in terms of limited excess sludge production without losses of the treatment capacity. Physical characteristics such as the viscosity and the filterability appear to be negatively affected by prolonged sludge retention times, but their values remain within the ranges normally reported for conventional activated sludge. |
| Source | Water science and technology 57 (3), pp. 319–322 |
| Keywords | Activity; Biomass yield; Filterability; Membrane bioreactors; Municipal sewage; Sludge retention time |
| Journal | Water science and technology |
| Editor | IWA Publishing, London, |
| Year | 2008 |
| Type | Articolo in rivista |
| DOI | 10.2166/wst.2008.118 |
| Authors | POLLICE A., LAERA G., SATURNO D., GIORDANO C., SANDULLI R. |
| Text | 42298 2008 10.2166/wst.2008.118 ISI Web of Science WOS 000253578800003 Activity; Biomass yield; Filterability; Membrane bioreactors; Municipal sewage; Sludge retention time OPTIMAL SLUDGE RETENTION TIME FOR A BENCH SCALE MBR TREATING MUNICIPAL SEWAGE POLLICE A., LAERA G., SATURNO D., GIORDANO C., SANDULLI R. Istituto di Ricerca Sulle Acque CNR, Viale F. De Blasio 5, 70132 Bari, Italy Universita degli Studi di Bari, Facolta di Scienze MM FF NN, I 70100 Bari, Italy Membrane bioreactors allow for higher sludge concentrations and improved degradation efficiencies with respect to conventional activated sludge. However, in the current practice these systems are often operated under sub optimal conditions, since so far no precise indications have yet been issued on the optimal operating conditions of MBR for municipal wastewater treatment. This paper reports some results of four years of operation of a bench scale membrane bioreactor where steady state conditions were investigated under different sludge retention times. The whole experimental campaign was oriented towards the investigation of optimal process conditions in terms of COD removal and nitrification, biomass activity and growth, and sludge characteristics. The membrane bioreactor treated real municipal sewage, and four different sludge ages were tested 20, 40, 60, and 80 days and compared with previous data on complete sludge retention. The results showed that the the biology of the system, as assessed by the oxygen uptake rate, is less affected than the sludge physical parameters. In particular, although the growth yield was observed to dramatically drop for SRT higher than 80 days, the biological activity was maintained under all the tested conditions. These considerations suggest that high SRT are convenient in terms of limited excess sludge production without losses of the treatment capacity. Physical characteristics such as the viscosity and the filterability appear to be negatively affected by prolonged sludge retention times, but their values remain within the ranges normally reported for conventional activated sludge. 57 http //www.iwaponline.com/wst/05703/wst057030319.htm Articolo pubblicato 2008_WatSciTech_57_3_319_322.pdf Articolo in rivista IWA Publishing 0273 1223 Water science and technology Water science and technology Water science and technology. Water sci. technol. alfieri.pollice POLLICE ALFIERI giuseppe.laera LAERA GIUSEPPE TA.P07.002.002 Sviluppo di nuovi processi di controllo dell inquinamento idrico. TA.P07.002.004 Processi biotecnologici e processi a membrana |