Back to Search
Start Over
An effective start-up of thermophilic UASB reactor by seeding mesophilically-grown granular sludge
- Source :
- Water Science & Technology; 1997, Vol. 36 Issue 6/7, p391, 0p
- Publication Year :
- 1997
-
Abstract
- After seeded with mesophilically-grown (35 deg. C) granular sludge, a laboratory-scale UASB reactor was thermophilically (55 deg. C) operated over 8 months by feeding with an alcohol distillery wastewater. Use of mesophilically-grown granules as a seed material proved to be more advantageous for rapid and stable start-up of thermophilic UASB process, compared with the use of suspended-growth sludge taken from a thermophilic anaerobic digester. The reactor accommodated successfully a COD loading 30 kgCOD7m<superscript>-3</superscript>7d<superscript>-1</superscript>, with a COD removal efficiency of 85%. However, during a period of 30 kgCOD7m<superscript>-3</superscript>7d<superscript>-1</superscript>, propionate accumulated in the effluent up to 300-600 mgCOD7l<superscript>-1</superscript>. Thermophilic cultivation caused a drastic increase of methanogenic activities (55 deg. C) of the retained sludge: 4.4 times for acetate, 4.6 times for propionate, and 3.5 times for hydrogen as large as those of the seed sludge. A considerably low value of propionate-fed methanogenic activity, i.e. only 1/5 of acetate-fed activity and only 1/23 of hydrogen-fed activity, suggested that the propionate degradation is subject to be a rate-limiting stepin thermophilic anaerobic processes. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 02731223
- Volume :
- 36
- Issue :
- 6/7
- Database :
- Complementary Index
- Journal :
- Water Science & Technology
- Publication Type :
- Academic Journal
- Accession number :
- 8405074
- Full Text :
- https://doi.org/10.1016/S0273-1223(97)00547-7