Journal article
Improving anaerobic sewage sludge digestion by implementation of a hyper-thermophilic prehydrolysis step
Journal of environmental management, Vol.88(4), pp.881-889
2008
Handle:
https://hdl.handle.net/2376/103340
PMID: 17686567
Abstract
The present study focuses on a two-step process for treatment and stabilisation of primary sludge. The process consists of a hyper-thermophilic hydrolysis step operated at 70
°C and a hydraulic retention time (HRT) of 2 days followed by a thermophilic (55
°C) anaerobic digestion step at a HRT of 13 days. A one-step anaerobic digester operated at 55
°C and 15 days HRT was used as a reference process. The two-step process was characterized by a 12% higher organic suspended solids removal efficiency and better pathogen reduction effect than the conventional one-step digestion. The microbial community of the digester fed with pre-treated sludge was characterised by a higher activity compared to that of the digester treating raw sludge. Moreover, the pre-treatment of the primary sludge resulted up to 48% increase of the methane potential (20.09 and 13.56
mmol
CH
4
g
−
VS
−1 with and without pre-treatment, respectively) and up to 115% increase of the methane production rate. Finally it was shown that the extra energy requirements for the operation of a pre-treatment step would be covered by the energy produced from the extra methane production and in addition there would be a significant energy surplus of 2.17
kJ
d
−1 for the system tested.
Metrics
7 Record Views
Details
- Title
- Improving anaerobic sewage sludge digestion by implementation of a hyper-thermophilic prehydrolysis step
- Creators
- Jingquan LuHariklia N GavalaIoannis V SkiadasZuzana MladenovskaBirgitte K Ahring
- Publication Details
- Journal of environmental management, Vol.88(4), pp.881-889
- Academic Unit
- Chemical Engineering and Bioengineering, School of
- Publisher
- Elsevier Ltd
- Identifiers
- 99900546798301842
- Language
- English
- Resource Type
- Journal article