[en] The mechanical properties of faecal sludge (FS) influence its moisture retention characteristics to a greater extent than other properties. A comprehensive fundamental characterisation of the mechanical properties is scarcely discussed in the literature. This research focused on bulk and true densities, porosity, particle size distribution and zeta-potential, extracellular polymeric substances, rheology and dilatancy, microstructure analysis, and compactibility in the context of using the FS as a substitute for soil in land reclamation and bioremediation processes. FSs from different on-site sanitation systems were collected from around Durban, South Africa. The porosity of the FSs varied between 42% and 63%, with the zeta-potential being negative, below 10 mV. Over 95% of the particles were <1000 µm. With its presence in the inner part of the solid particles, tightly bound extra-cellular polymeric substances (TB-EPSs) influenced the stability of the sludge by tightly attaching to the cell walls, with the highest being in the septic tank with the greywater sample. More proteins than carbohydrates also confirmed characterised the anaerobic nature of the sludge. The results of the textural properties using a penetrometer showed that the initial slope of the positive part of the penetration curve was related to the stiffness of the sludge sample and similar to that of sewage sludge. The dynamic oscillatory measurements exhibited a firm gel-like behaviour with a linear viscoelastic behaviour of the sludges due to the change in EPSs because of anaerobicity. The high-TS samples exhibited the role of moisture as a lubricating agent on the motion of solid particles, leading to dilatancy with reduced moisture, where the yield stress was no longer associated with the viscous forces but with the frictional contacts of solid–solid particle interactions. The filtration–compression cell test showed good compactibility, but the presence of unbound moisture even at a high pressure of 300 kPa meant that not all unbound moisture was easily removable. The moisture retention behaviour of FS was influenced by its mechanical properties, and any interventional changes to these properties can result in the release of the bound moisture of FS.
Disciplines :
Chemical engineering
Author, co-author :
Rayavellore Suryakumar, Arun Kumar ; WASH R&D Centre, University of KwaZulu-Natal, Durban 4000, South Africa
Léonard, Angélique ; Université de Liège - ULiège > Department of Chemical Engineering > PEPs - Products, Environment, and Processes
Pocock, Jonathan; WASH R&D Centre, University of KwaZulu-Natal, Durban 4000, South Africa ; Department of Chemical Engineering, University of KwaZulu-Natal, Durban 4000, South Africa
Septien, Santiago; WASH R&D Centre, University of KwaZulu-Natal, Durban 4000, South Africa
Language :
English
Title :
Mechanical Properties of Faecal Sludge and Its Influence on Moisture Retention
Diener S. Semiyaga S. Niwagaba C.B. Muspratt A.M. Gning J.B. Mbéguéré M. Ennin J.E. Zurbrugg C. Strande L. A value proposition: Resource recovery from faecal sludge—Can it be the driver for improved sanitation? Resour. Conserv. Recycl. 2014 88 32 38 10.1016/j.resconrec.2014.04.005
Mallory A. Holm R. Parker A. A review of the financial value of faecal sludge reuse in low-income countries Sustainability 2020 12 8334 10.3390/su12208334
Muoghalu C. Semiyaga S. Manga M. Faecal sludge emptying in Sub-Saharan Africa, South and Southeast Asia: A systematic review of emptying technology choices, challenges, and improvement initiatives Front. Environ. Sci. 2023 11 1097716 10.3389/fenvs.2023.1097716
Tasnim G. Khan M.D. Farooqi I.H. Basheer F. Management of Wastewater and Sludge. Sources, Characteristics, Treatment Technologies and Disposal Methods for Faecal Sludge. Manag Wastewater Sludge New Approaches Routledge London, UK 2023 297 337 10.1201/9781003202431-16
Semiyaga S. Okure M.A.E. Niwagaba C.B. Nyenje P.M. Kansiime F. Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums: Faecal sludge pre-treatment by dewatering Int. J. Environ. Sci. Technol. 2016 14 151 164 10.1007/s13762-016-1134-9
Bourgault C. Lessard P. Remington C. Dorea C.C. Experimental determination of moisture sorption isotherm of fecal sludge Water 2019 11 303 10.3390/w11020303
Rose C. Parker A. Jefferson B. Cartmell E. The characterization of feces and urine: A review of the literature to inform advanced treatment technology Crit. Rev. Environ. Sci. Technol. 2015 45 1827 1879 10.1080/10643389.2014.1000761 26246784
Gold M. Harada H. Therrien J.-D. Nishida T. Cunningham M. Semiyaga S. Fujii S. Dorea C. Nguyen V.-A. Strande L. Cross-country analysis of faecal sludge dewatering Environ. Technol. 2018 39 3077 3087 10.1080/09593330.2017.1374472
Stone R. Ekwue E. Clarke R. Engineering Properties of Sewage Sludge in Trinidad J. Agric. Eng. Res. 1998 70 221 230 10.1006/jaer.1998.0266
Gold M. Dayer P. Faye M.C.A.S. Clair G. Seck A. Niang S. Morgenroth E. Strande L. Locally produced natural conditioners for dewatering of faecal sludge Environ. Technol. 2016 37 2802 2814 10.1080/09593330.2016.1165293
Arlabosse P. Nzihou A. Oakley S. Sauceau M. Tribout C. Wang F. Sludge Handbook on Characterization of Biomass, Biowaste and Related by-Products Nzihou A. Springer International Publishing Cham, Switzerland 2020 939 1083
Kuśnierz M. Wiercik P. Analysis of particle size and fractal dimensions of suspensions contained in raw sewage, treated sewage and activated sludge Arch. Environ. Prot. 2016 42 67 76 10.1515/aep-2016-0031
Xie S. Wu Y. Wang W. Wang J. Luo Z. Li S. Effects of acid/alkaline pretreatment and gamma-ray irradiation on extracellular polymeric substances from sewage sludge Radiat. Phys. Chem. 2014 97 349 353 10.1016/j.radphyschem.2013.07.026
Dai Q. Ma L. Ren N. Ning P. Guo Z. Xie L. Gao H. Investigation on extracellular polymeric substances, sludge flocs morphology, bound water release and dewatering performance of sewage sludge under pretreatment with modified phosphogypsum Water Res. 2018 142 337 346 10.1016/j.watres.2018.06.009
Faye M.C.A.S. Zhang K.K. Peng S. Zhang Y. Sludge dewaterability: The variation of extracellular polymeric substances during sludge conditioning with two natural organic conditioners J. Environ. Manag. 2019 251 109559 10.1016/j.jenvman.2019.109559
Yang S.-F. Li X.-Y. Influences of extracellular polymeric substances (EPS) on the characteristics of activated sludge under non-steady-state conditions Process Biochem. 2008 44 91 96 10.1016/j.procbio.2008.09.010
Li X. Yang S. Influence of loosely bound extracellular polymeric substances (EPS) on the flocculation, sedimentation and dewaterability of activated sludge Water Res. 2007 41 1022 1030 10.1016/j.watres.2006.06.037
Sheng G.-P. Yu H.-Q. Li X.-Y. Extracellular polymeric substances (EPS) of microbial aggregates in biological wastewater treatment systems: A review Biotechnol. Adv. 2010 28 882 894 10.1016/j.biotechadv.2010.08.001 20705128
FAO, Quality Assurance for Animal Feed Analysis Laboratories FAO Animal Production and Health Manual No. 14 FAO Rome, Italy 2011
Nzihou A. Handbook on Characterization of Biomass, Biowaste and Related By-Products Springer Berlin/Heidelberg, Germany 2020
Pambou Y.-B. Influence du Conditionnement et de la Déshydratation Mécanique sur le Séchage des Boues D’épuration Université de Liège Liège, Belgium 2016
Pambou Y. Fraikin L. Salmon T. Crine M. Léonard A. Sludge dewatering and drying: About the difficulty of making experiments with a non-stabilized material Desalination Water Treat. 2016 57 13841 13856 10.1080/19443994.2015.1060534
Agoda-Tandjawa G. Dieudé-Fauvel E. Girault R. Baudez J.-C. Using water activity measurements to evaluate rheological consistency and structure strength of sludge Chem. Eng. J. 2013 228 799 805 10.1016/j.cej.2013.05.012
Mouzaoui M. Baudez J. Sauceau M. Arlabosse P. Experimental rheological procedure adapted to pasty dewatered sludge up to 45% dry matter Water Res. 2018 133 1 7 10.1016/j.watres.2018.01.006
Zhang Y. Lian G. Dong C. Cai M. Song Z. Shi Y. Wu L. Jin M. Wei Z. Optimizing and understanding the pressurized vertical electro-osmotic dewatering of activated sludge Process. Saf. Environ. Prot. 2020 140 392 402 10.1016/j.psep.2020.05.016
Deng W. Li X. Yan J. Wang F. Chi Y. Cen K. Moisture distribution in sludges based on different testing methods J. Environ. Sci. 2011 23 875 880 10.1016/S1001-0742(10)60518-9
Li S. Wang C. Zhang X. Zou L. Dai Z. Classification and characterization of bound water in marine mucky silty clay J. Soils Sediments 2019 19 2509 2519 10.1007/s11368-019-02242-5
Lin B. Cerato A.B. Applications of SEM and ESEM in microstructural investigation of shale-weathered expansive soils along swelling-shrinkage cycles Eng. Geol. 2014 177 66 74 10.1016/j.enggeo.2014.05.006
Olböter L. Vogelpohl A. Influence of particle size distribution on the dewatering of organic sludges Water Sci. Technol. 1993 28 149 157 10.2166/wst.1993.0037
Karczmarek A.M. Gaca J. Effect of two-stage thermal disintegration on particle size distribution in sewage sludge Pol. J. Chem. Technol. 2013 15 69 73 10.2478/pjct-2013-0047
Kumar A. Suryakumar R. Mercer E. Pocock J. Septien S. Determination of Unbound-Bound Moisture Interface of Faecal Sludges from Different On-Site Sanitation Systems Heliyon 2024 10.2139/ssrn.4934796
Cetin S. Erdincler A. The role of carbohydrate and protein parts of extracellular polymeric substances on the dewaterability of biological sludges Water Sci. Technol. 2004 50 49 56 10.2166/wst.2004.0532 15580994
Marsalek R. Particle size and Zeta Potential of ZnO APCBEE Procedia 2014 9 13 17 10.1016/j.apcbee.2014.01.003
Comte S. Guibaud G. Baudu M. Effect of extraction method on EPS from activated sludge: An HPSEC investigation J. Hazard. Mater. 2006 140 129 137 10.1016/j.jhazmat.2006.06.058 16879910
Peng S. Hu A. Ai J. Zhang W. Wang D. Changes in molecular structure of extracellular polymeric substances (EPS) with temperature in relation to sludge macro-physical properties Water Res. 2021 201 117316 10.1016/j.watres.2021.117316
Peng G. Ye F. Li Y. Investigation of extracellular polymer substances (EPS) and physicochemical properties of activated sludge from different municipal and industrial wastewater treatment plants Environ. Technol. 2012 33 857 863 10.1080/09593330.2011.601763
Houghton J.J. Quarmby J. Stephenson T. Municipal wastewater sludge dewaterability and the presence of microbial extracellular polymer Water Sci. Technol. 2001 44 373 379 10.2166/wst.2001.0792 11548008
Léonard A. Blandin G. Crine M. Importance of Rheological Properties When Drying Sludge in a Fixed Bed Lab. Chem. Eng. Univ. 2014 III 102 150
Azeddine F. Sergio P.A. Angélique L. El Khadir L. Ali I. El Houssayne B. Rheological Behavior and Characterization of Drinking Water Treatment Sludge from Morocco Clean Technol. 2023 5 259 273 10.3390/cleantechnol5010015
Li B. Wang F. Chi Y. Yan J.H. Adhesion and Cohesion Characteristics of Sewage Sludge During Drying Dry. Technol. 2014 32 1598 1607 10.1080/07373937.2014.910522
Hil A. Judenne E. Remy M. The effect of lime treatment on sludge rheological properties Technology 2005 59 1 6
Mezger T. The Rheology Handbook Vincentz Network Hannover, Germany 2020
Rodríguez N.H. Ramírez S.M. Varela M.B. Guillem M. Puig J. Larrotcha E. Flores J. Re-use of drinking water treatment plant (DWTP) sludge: Characterization and technological behaviour of cement mortars with atomized sludge additions Cem. Concr. Res. 2010 40 778 786 10.1016/j.cemconres.2009.11.012
Liu Y. Zhuge Y. Chow C.W. Keegan A. Li D. Pham P.N. Huang J. Siddique R. Utilization of drinking water treatment sludge in concrete paving blocks: Microstructural analysis, durability and leaching properties J. Environ. Manag. 2020 262 110352 10.1016/j.jenvman.2020.110352
Dignac M.-F. Ginestet P. Rybacki D. Bruchet A. Urbain V. Scribe P. research, and undefined Fate of Wastewater Organic Pollution During Activated Sludge Treatment: Nature of Residual Organic Matter Elsevier Amsterdam, The Netherlands 2000
Ling Y.P. Tham R.-H. Lim S.-M. Fahim M. Ooi C.-H. Krishnan P. Matsumoto A. Yeoh F.-Y. Evaluation and reutilization of water sludge from fresh water processing plant as a green clay substituent Appl. Clay Sci. 2017 143 300 306 10.1016/j.clay.2017.04.007
Li H. Zou S. Li C. Liming Pretreatment Reduces Sludge Build-Up on the Dryer Wall during Thermal Drying Dry. Technol. 2012 30 1563 1569 10.1080/07373937.2012.697947
Léonard A. Royer S. Blandin G. Salmon T. Fraikin L. Crine M. Importance of Mixing Conditions During Sludge Liming Prior to Their Convective Drying Proceedings of the EuroDrying’2011: III European Drying Conference Palma de Mallorca, Spain 26–28 October 2011 26 28
Huron Y. Salmon T. Crine M. Blandin G. Léonard A. Effect of liming on the convective drying of urban residual sludges Asia-Pac. J. Chem. Eng. 2010 5 909 914 10.1002/apj.421
Benlalla A. Elmoussaouiti M. Cherkaoui M. Ait Hsain L. Assafi M. Characterization and valorization of drinking water sludges applied to agricultural spreading J. Mater. Environ. Sci. 2015 6 1692 1698
Malkin A.Y. Derkach S.R. Kulichikhin V.G. Rheology of Gels and Yielding Liquids Gels 2023 9 715 10.3390/gels9090715 37754396
Ruiz T. Wisniewski C. Correlation between dewatering and hydro-textural characteristics of sewage sludge during drying Sep. Purif. Technol. 2008 61 204 210 10.1016/j.seppur.2007.07.054
Jiang J. Wu J. Poncin S. Li H.Z. Rheological characteristics of highly concentrated anaerobic digested sludge Biochem. Eng. J. 2014 86 57 61 10.1016/j.bej.2014.03.007
Zhang S. Liang J. Huang J. Huang S. Zheng L. Sun S. Zhong Z. Zhang X. Yu X. Guan Z. Analysis of the relationship of extracellular polymeric substances to the dewaterability and rheological properties of sludge treated by acidification and anaerobic mesophilic digestion J. Hazard. Mater. 2019 369 31 39 10.1016/j.jhazmat.2019.02.012 30763797
Feng G. Hu Z. Ma H. Bai T. Guo Y. Hao Y. Semi-solid rheology characterization of sludge conditioned with inorganic coagulants Water Sci. Technol. 2019 80 2158 2168 10.2166/wst.2020.022 32198333
Sollich P. Soft Glassy Rheology Molecular Gels Weiss R.G. Terech P. Springer Dordrecht, The Netherlands 2006 10.1007/1-4020-3689-2_6
Vaxelaire J. Olivier J. Conditioning for municipal sludge dewatering. From filtration compression cell tests to belt press Dry. Technol. 2006 24 1225 1233 10.1080/07373930600838090
Scales P. Dixon D. Harbour P. Stickland A. The fundamentals of wastewater sludge characterization and filtration Water Sci. Technol. 2004 49 67 72 10.2166/wst.2004.0610 15259939
Wu B. Dai X. Chai X. Critical review on dewatering of sewage sludge: Influential mechanism, conditioning technologies and implications to sludge re-utilizations Water Res. 2020 180 115912 10.1016/j.watres.2020.115912 32422413
Raynaud M. Vaxelaire J. Olivier J. Dieudé-Fauvel E. Baudez J.-C. Compression dewatering of municipal activated sludge: Effects of salt and pH Water Res. 2012 46 4448 4456 10.1016/j.watres.2012.05.047
Raynaud J.-C. Vaxelaire M. Heritier J. Baudez P. Activated sludge dewatering in a filtration compression cell: Deviations in comparison to the classical theory Technology 2009 7 743 753 10.1002/apj.407
