A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance

Large quantities of sludge is generated from different sections of a wastewater treatment plant operation. Sludge can be a solid, semisolid or liquid muddy residual material. Understanding the flow behaviour and rheological properties of sewage sludge at different sections of a wastewater treatment...

Full description

Bibliographic Details
Main Authors: Hong, E., Yeneneh, A., Sen, Tushar, Ang, H., Kayaalp, A.
Format: Journal Article
Published: 2018
Online Access:http://hdl.handle.net/20.500.11937/69166
_version_ 1848761985298071552
author Hong, E.
Yeneneh, A.
Sen, Tushar
Ang, H.
Kayaalp, A.
author_facet Hong, E.
Yeneneh, A.
Sen, Tushar
Ang, H.
Kayaalp, A.
author_sort Hong, E.
building Curtin Institutional Repository
collection Online Access
description Large quantities of sludge is generated from different sections of a wastewater treatment plant operation. Sludge can be a solid, semisolid or liquid muddy residual material. Understanding the flow behaviour and rheological properties of sewage sludge at different sections of a wastewater treatment plant (WWTP) is important for the design of pumping system, mixing, hydrodynamics and mass transfer rates of various sludge treatment units, optimization of conditioning dose and for sustainable sludge management. The current article provides a comprehensive review on up to date literature information on rheological behaviour of raw primary sludge, excess activated sludge, thickened excess activated sludge, mixture of raw primary and thickened excess activated sludge (mixed sludge), digested sludge, and biosolid under the influence of different operating parameters and their impacts on process performance. The influences of various process parameters such as solid concentration, temperature, pH, floc particle size, primary to secondary sludge mixing ratio, aging and conditioning agent doses on the rheological behaviour of sludge from different treatment units of WWTPs are critically analysed here. Yield stress was reported to increase with increasing solid concentration for all types of sludge whereas viscosity showed a decreasing trend with decreasing total solid concentration and percentage of thickened excess activated sludge in the mixture. Temperature showed an inverse relationship with yield stress and viscosity. Viscosity was reported to be decreased with decrease in pH. The effect of various conditioning agents on the rheological behaviour of sludge are also discussed here. The applicability and practical significance of various rheological models such as Bingham, Power Law (Ostwald), Herschel-Bulkley, Casson, Sisko, Careau, and Cross models to experimental rheological characteristics of various sludges were presented here. The reported results on various rheological parameters such as shear stress, yield stress, flow index, infinite, zero-rate viscosity, and flow consistency index of different sludge types obtained from the best fitted model were also compiled here. Conclusions have been drawn from the literature reviewed and few suggestions for future research direction are proposed.
first_indexed 2025-11-14T10:40:22Z
format Journal Article
id curtin-20.500.11937-69166
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T10:40:22Z
publishDate 2018
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-691662020-06-15T03:57:13Z A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance Hong, E. Yeneneh, A. Sen, Tushar Ang, H. Kayaalp, A. Large quantities of sludge is generated from different sections of a wastewater treatment plant operation. Sludge can be a solid, semisolid or liquid muddy residual material. Understanding the flow behaviour and rheological properties of sewage sludge at different sections of a wastewater treatment plant (WWTP) is important for the design of pumping system, mixing, hydrodynamics and mass transfer rates of various sludge treatment units, optimization of conditioning dose and for sustainable sludge management. The current article provides a comprehensive review on up to date literature information on rheological behaviour of raw primary sludge, excess activated sludge, thickened excess activated sludge, mixture of raw primary and thickened excess activated sludge (mixed sludge), digested sludge, and biosolid under the influence of different operating parameters and their impacts on process performance. The influences of various process parameters such as solid concentration, temperature, pH, floc particle size, primary to secondary sludge mixing ratio, aging and conditioning agent doses on the rheological behaviour of sludge from different treatment units of WWTPs are critically analysed here. Yield stress was reported to increase with increasing solid concentration for all types of sludge whereas viscosity showed a decreasing trend with decreasing total solid concentration and percentage of thickened excess activated sludge in the mixture. Temperature showed an inverse relationship with yield stress and viscosity. Viscosity was reported to be decreased with decrease in pH. The effect of various conditioning agents on the rheological behaviour of sludge are also discussed here. The applicability and practical significance of various rheological models such as Bingham, Power Law (Ostwald), Herschel-Bulkley, Casson, Sisko, Careau, and Cross models to experimental rheological characteristics of various sludges were presented here. The reported results on various rheological parameters such as shear stress, yield stress, flow index, infinite, zero-rate viscosity, and flow consistency index of different sludge types obtained from the best fitted model were also compiled here. Conclusions have been drawn from the literature reviewed and few suggestions for future research direction are proposed. 2018 Journal Article http://hdl.handle.net/20.500.11937/69166 10.1016/j.cis.2018.06.002 fulltext
spellingShingle Hong, E.
Yeneneh, A.
Sen, Tushar
Ang, H.
Kayaalp, A.
A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
title A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
title_full A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
title_fullStr A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
title_full_unstemmed A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
title_short A comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
title_sort comprehensive review on rheological studies of sludge from various sections of municipal wastewater treatment plants for enhancement of process performance
url http://hdl.handle.net/20.500.11937/69166