effect of flow equalisation and prefermentation on the sludge production and sludge characteristics in a BNR plant

A full-scale study investigated the influence of diurnal flow equalisation and prefermentation on the characteristics of sludge. The diurnal variations in the sludge concentration and the level of sludge blanket in the secondary clarifiers were evened out significantly with the use of an equalizatio...

Full description

Saved in:
Bibliographic Details
Published in:Water science and technology 2008-01, Vol.57 (12), p.2023-2029
Main Authors: Mikola, A, Rautiainen, J, Kiuru, H
Format: Article
Language:English
Subjects:
Activated sludge
Aeration
Biological activity
bioreactors
Clarifiers
denitrification
diurnal variation
Diurnal variations
Equalization
equipment performance
nutrients
Reproducibility of Results
Sewage - analysis
Sludge
solids
Suspended solids
Waste Disposal, Fluid - methods
wastewater treatment
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A full-scale study investigated the influence of diurnal flow equalisation and prefermentation on the characteristics of sludge. The diurnal variations in the sludge concentration and the level of sludge blanket in the secondary clarifiers were evened out significantly with the use of an equalization basin. Stable conditions in the aeration basin and in the secondary clarifiers contributed to the improvements in the performance of the BNR plant. A decrease in the waste activated sludge production and an improvement in the settleability were also observed. The low WAS yield was attributed to the low yield COD compounds produced by the prefermentation, longer sludge age and constant conditions obtained by the flow equalisation. Some evidence was found that good settling properties would be related to the amount of suspended solids fed to the biological process as well as to the good performance of the biological process.
ISSN:0273-1223
1996-9732
DOI:10.2166/wst.2008.618