Back to Search
Start Over
Influence of effluent-recirculation condition on the process performance of expanded granular sludge bed reactor for treating low strength wastewater.
- Source :
- Water Science & Technology; 2008, Vol. 57 Issue 6, p869-873, 5p, 1 Chart, 6 Graphs
- Publication Year :
- 2008
-
Abstract
- A 2.0 L volume of EGSB reactor was operated at 208C for more than 500 days with 0.3-0.4 g COD/L of sucrose base wastewater to investigate the influence of effluent-recirculation on the process performance. At the start up period, the reactor was operated in EGSB mode with 5 m/h upflow velocity by continuous effluent recirculation. The COD loading was set to 7.2-9.6 kg COD/m3 day with HRT of 1 hour. However, in this mode, EGSB reactor exhibited insufficient COD removal efficiency, i.e., 50-60%. Therefore, UASB mode (without recirculation, 0.7 m/h upflow velocity) was used for 30 minutes in every 40 minutes cycle to increase the COD concentration in the sludge bed. As a result, an excellent process performance was shown. The COD removal efficiency increased from 65% to 91% and the reactor could maintain a good physical property of retained sludge (sludge concentration: 33.4 g VSS/L and SVI: 25 mL/g VSS). Furthermore, retained sludge possessed sufficient level of methanogenic activity at 208C. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 02731223
- Volume :
- 57
- Issue :
- 6
- Database :
- Complementary Index
- Journal :
- Water Science & Technology
- Publication Type :
- Academic Journal
- Accession number :
- 31672535
- Full Text :
- https://doi.org/10.2166/wst.2008.045