| Title: | The influence of temperature and SRT on high-solid digestion of municipal sewage sludge |
| Author(s): | Jahn L; Baumgartner T; Svardal K; Krampe J; |
| Address: | "Institute for Water Quality, Resource and Waste Management, Vienna University of Technology, Karlsplatz 13/226-1, Vienna 1040, Austria E-mail: ljahn@iwag.tuwien.ac.at" |
| ISSN/ISBN: | 0273-1223 (Print) 0273-1223 (Linking) |
| Abstract: | "The influence of temperature and solids retention time (SRT) on high-solid digestion of municipal sewage sludge was investigated in laboratory-scale reactors. Digestion with high-solid concentration reduces the required digestion volume and is advantageous for urban areas. The experimental conditions comprised total suspended solids (TSS) in digested sludge between 4.0 and 4.6%, temperatures in a range of 33 to 41 degrees C and the SRT between 10 and 25 d. High-solid digestion operates with increased NH4-N concentrations released from organic compounds. The anaerobic process can be limited by high NH4-N concentration and toxic NH3. In this study a stable digestion was observed up to 2,000 mg L(-1) NH4-N and 75 mg L(-1) NH3. Volatile suspended solids (VSS) and chemical oxygen demand removal was 53% and 57% respectively. However, digestion with 10 d SRT led to a declined VSS removal of 49%. The removal at 41 and 37 degrees C showed minor differences, while reduced NH4-N release and reduced methane production were observed at 33 degrees C. For economic reasons, high-solid digestion at 41 degrees C is not recommended, but will not impair VSS removal. The outcomes of this study confirm that digestion with up to 7.8% TSS in the feed is feasible for the tested temperatures and SRT down to 15 d" |
| Keywords: | Ammonia/chemistry Biological Oxygen Demand Analysis *Bioreactors Organic Chemicals Sewage/*chemistry *Temperature Time Factors; |
| Notes: | "MedlineJahn, L Baumgartner, T Svardal, K Krampe, J eng England 2016/08/18 Water Sci Technol. 2016; 74(4):836-43. doi: 10.2166/wst.2016.264" |
