Abstract
Excess sludge reduction in activated sludge plants can, inter alia, be achieved by the integration of sludge disintegration technology in the recycle stream of activated sludge treatment plants. In previous research by Lambert et al. (2016), a long-term experimental study of 120 days at a biodiesel production plant demonstrated that ultrasonic sludge disintegration can result in a substantial reduction of waste sludge of about 45%, and this at a relatively low specific energy. Moreover, it was revealed from this pilot experiment that the efficiency of the excess sludge reduction, indicated as SRE (Sludge Reduction Efficiency), increases when the activated sludge plant is operated at a higher sludge retention time (SRT). This is an important finding, because this would mean that the ultrasonic technology can be operated more cost efficiently at a higher sludge retention time. To confirm this finding and to give a deeper insight into the underlying mechanisms and long-term effects that promote the excess sludge reduction, lab-scale aerobic digestion experiments were performed. Both the endogenous respiration rate and the VSS concentration were monitored during the 30 days’ experimental period, and could give more information about the fate and the biodegradation of the particulate COD in activated sludge. Modeling the batch tests indicated a higher endogenous residue decay rate (bXE) and a clear instantaneous change in the active biomass concentration, of nearly 50%, which can be directly assigned to the ultrasonic pre-treatment. This has ultimately led to a more thorough VSS reduction at the end of the digestion period.
References
Courchaine RJ (1968) Significance of nitrification in stream analysis: effects on the oxygen balance. J Water Pollut Control Fed 40(5):835–847
Dold PL, Ekama GA, Marais G (1980) A general model for the activated sludge process. Prog Water Technol 12(6):47–77
Lambert N, Van Eyck K, Feremans J, Van den Broeck R, Smets I, Dewil R (2016) Ultrasonic sludge disintegration in nutrient deficient activated sludge wastewater treatment plants. In: 2nd IWA conference on holistic sludge management, Malmö, Sweden, 7–9 June 2016
Lee SH, Chung CW, Yu YJ, Rhee YH (2009) Effect of alkaline protease-producing Exiguobacterium sp. YS1 inoculation on the solubilization and bacterial community of waste activated sludge. Biores Technol 100(20):4597–4603
Mahmood T, Elliott A (2006) A review of secondary sludge reduction technologies for the pulp and paper industry. Water Res 40(11):2093–2112
Marais G, Ekama GA (1976) The activated sludge process part I-steady state behaviour. Water SA 2(4):164–200
Mohammadi AR, Mehrdadi N, Bidhendi GN, Torabian A (2011) Excess sludge reduction using ultrasonic waves in biological wastewater treatment. Desalination 275(1):67–73
Ramdani A, Dold P, Déléris S, Lamarre D, Gadbois A, Comeau Y (2010) Biodegradation of the endogenous residue of activated sludge. Water Res 44(7):2179–2188
Tamis J, Van Schouwenburg G, Kleerebezem R, van Loosdrecht MCM (2011) A full scale worm reactor for efficient sludge reduction by predation in a wastewater treatment plant. Water Res 45(18):5916–5924
van Haandel AC, Catunda PF, Araujo LDS (1998) Biological sludge stabilisation Part 1: Kinetics of aerobic sludge digestion. Water SA 24(3):223–230
Van Loosdrecht MC, Henze M (1999) Maintenance, endogeneous respiration, lysis, decay and predation. Water Sci Technol 39(1):107–117
Wei Y, Van Houten RT, Borger AR, Eikelboom DH, Fan Y (2003) Minimization of excess sludge production for biological wastewater treatment. Water Res 37(18):4453–4467
Yang SS, Guo WQ, Zhou XJ, Meng ZH, Liu B, Ren NQ (2011) Optimization of operating parameters for sludge process reduction under alternating aerobic/oxygen-limited conditions by response surface methodology. Biores Technol 102(21):9843–9851
Zhang X, Tian Y, Wang Q, Chen L, Wang X (2012) Heavy metal distribution and speciation during sludge reduction using aquatic worms. Biores Technol 126:41–47
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Work supported in part by the IWT 090186 and IWT 110171 TETRA-projects.
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Lambert, N., Van Aken, P., Smets, I., Dewil, R. (2017). Effect of Sludge Retention Time on the Efficiency of Excess Sludge Reduction by Ultrasonic Disintegration. In: Mannina, G. (eds) Frontiers in Wastewater Treatment and Modelling. FICWTM 2017. Lecture Notes in Civil Engineering , vol 4. Springer, Cham. https://doi.org/10.1007/978-3-319-58421-8_20
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DOI: https://doi.org/10.1007/978-3-319-58421-8_20
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