Optimization of Aeration Strategies in Moving Bed Biofilm Reactor for Hospital Wastewater Treatment
Main Article Content
Abstract
The growing complexity of hospital wastewater presents significant challenges for traditional treatment methods, highlighting the need for innovative and energy-efficient alternatives. This study investigated the effect of different aeration strategies on the biological removal efficiency of carbon and nitrogen in a laboratory-scale moving bed biofilm reactor (MBBR). The system was operated under three aeration conditions: continuous aeration and two intermittent aeration regimes. The results show that intermittent aeration enhanced nitrogen removal through simultaneous nitrification-denitrification (SND) while maintaining high organic matter degradation efficiency. In Phase I (continuous aeration), carbon removal efficiency reached 87.4%, whereas total nitrogen removal remained below 20% due to the absence of anoxic conditions. In contrast, intermittent aeration in Phases II and III significantly improved nitrogen removal to 82.5% and 87.8%, respectively, while achieving comparable carbon removal rates. The most effective operational mode involved a 40-min aeration period followed by 20 min without aeration, facilitating denitrification and minimizing energy consumption. Furthermore, the system maintained stable biofilm development, with mixed liquor suspended solids (MLSS) concentrations ranging from 1.9 to 3.3 g/L. Despite the low MLSS concentration, the system consistently exhibited high treatment performance, underscoring the robustness of biofilm-based processes in MBBR systems. These findings highlight the potential of optimized aeration strategies in MBBR systems to enhance treatment efficiency while reducing operational costs. This study provides valuable guidance for designing sustainable hospital wastewater treatment systems that meet stringent regulatory standards.
Article Details

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Copyright Transfer Statement
The copyright of this article is transferred to Current Applied Science and Technology journal with effect if and when the article is accepted for publication. The copyright transfer covers the exclusive right to reproduce and distribute the article, including reprints, translations, photographic reproductions, electronic form (offline, online) or any other reproductions of similar nature.
The author warrants that this contribution is original and that he/she has full power to make this grant. The author signs for and accepts responsibility for releasing this material on behalf of any and all co-authors.
Here is the link for download: Copyright transfer form.pdf
References
Accinelli, C., Saccà, M. L., Mencarelli, M., & Vicari, A. (2012). Application of bioplastic moving bed biofilm carriers for the removal of synthetic pollutants from wastewater. Bioresource Technology, 120, 180-186. https://doi.org/10.1016/j.biortech.2012.06.056
Almomani, F., & Bohsale, R. R. (2020). Optimizing nutrient removal of moving bed biofilm reactor process using response surface methodology. Bioresource Technology, 305, Article 123059. https://doi.org/10.1016/j.biortech.2020.123059
APHA. (2017). Standard methods for the examination of water and wastewater (23rd Ed.). American Public Health Association.
Bhandari, G., Chaudhary, P., Gangola, S., Gupta, S., Gupta, A., Rafatullah, M., & Chen, S. (2023). A review on hospital wastewater treatment technologies: Current management practices and future prospects. Journal of Water Process Engineering, 56, Article 104516. https://doi.org/10.1016/j.jwpe.2023.104516
Boavida-Dias, R., Silva, J. R., Santos, A. D., Martins, R. C., Castro, L. M., & Quinta-Ferreira, R. M. (2022). A comparison of biosolids production and system efficiency between activated sludge, moving bed biofilm reactor, and sequencing batch moving bed biofilm reactor in the dairy wastewater treatment. Sustainability, 14(5), Article 5. https://doi.org/10.3390/su14052702
Cao, Y., Zhang, C., Rong, H., Zheng, G., & Zhao, L. (2017). The effect of dissolved oxygen concentration (DO) on oxygen diffusion and bacterial community structure in moving bed sequencing batch reactor (MBSBR). Water Research, 108, 86-94. https://doi.org/10.1016/j.watres.2016.10.063
Dai, W., Pang, J.-W., Ding, J., Wang, Y.-Q., Zhang, L.-Y., Ren, N.-Q., & Yang, S.-S. (2023). Study on the removal characteristics and degradation pathways of highly toxic and refractory organic pollutants in real pharmaceutical factory wastewater treated by a pilot-scale integrated process. Frontiers in Microbiology, 14, Article 1128233. https://doi.org/10.3389/fmicb.2023.1128233
Derco, J., Urminská, B., Kovács, A., & Šimkovič, K. (2017). Biological nutrient removal in an intermittently aerated bioreactor. Chemical and Biochemical Engineering Quarterly, 31(2), 179-185. https://doi.org/10.15255/CABEQ.2016.1026
Di Bella, G., & Mannina, G. (2020). Intermittent aeration in a hybrid moving bed biofilm reactor for carbon and nutrient biological removal. Water, 12(2), Article 492. https://doi.org/10.3390/w12020492
Eapen, J. V., Thomas, S., Antony, S., George, P., & Antony, J. (2024). A review of the effects of pharmaceutical pollutants on humans and aquatic ecosystem. Exploration of Drug Science, 2(5), 484-507. https://doi.org/10.37349/eds.2024.00058
Eshamuddin, M., Zuccaro, G., Nourrit, G., & Albasi, C. (2024). The influence of process operating conditions on the microbial community structure in the moving bed biofilm reactor at phylum and class level: A review. Journal of Environmental Chemical Engineering, 12(4), Article 113266. https://doi.org/10.1016/j.jece.2024.113266
Fonseca, D. L., & Bassin, J. P. (2019). Investigating the most appropriate methods for attached solids determination in moving-bed biofilm reactors. Bioprocess and Biosystems Engineering, 42(11), 1867-1878. https://doi.org/10.1007/s00449-019-02182-x
Gupta, B., Gupta, A. K., Ghosal, P. S., Lal, S., Saidulu, D., Srivastava, A., & Upadhyay, M. (2022). Recent advances in application of moving bed biofilm reactor for wastewater treatment: Insights into critical operational parameters, modifications, field-scale performance, and sustainable aspects. Journal of Environmental Chemical Engineering, 10(3), Article 107742. https://doi.org/10.1016/j.jece.2022.107742
Henze, M., Gujer, W., Mino, T., & van Loosedrecht, M. (2006). Activated sludge models ASM1, ASM2, ASM2d and ASM3. IWA Publishing. https://doi.org/10.2166/9781780402369
Hibiya, K., Terada, A., Tsuneda, S., & Hirata, A. (2003). Simultaneous nitrification and denitrification by controlling vertical and horizontal microenvironment in a membrane-aerated biofilm reactor. Journal of Biotechnology, 100(1), 23-32. https://doi.org/10.1016/S0168-1656(02)00227-4
Hidaka, T., Yamada, H., Kawamura, M., & Tsuno, H. (2002). Effect of dissolved oxygen conditions on nitrogen removal in continuously fed intermittent-aeration process with two tanks. Water Science and Technology, 45(12), 181-188. https://doi.org/10.2166/wst.2002.0425
JSWA. (1997). Japanese Standard Methods of the Examination of Wastewater. Japanese Sewage Works Association.
Jiang, Q., Ngo, H. H., Nghiem, L. D., Hai, F. I., Price, W. E., Zhang, J., Liang, S., Deng, L., & Guo, W. (2018). Effect of hydraulic retention time on the performance of a hybrid moving bed biofilm reactor-membrane bioreactor system for micropollutants removal from municipal wastewater. Bioresource Technology, 247, 1228-1232. https://doi.org/10.1016/j.biortech.2017.09.114
Kawan, J. A., Suja’, F., Pramanik, S. K., Yusof, A., Rahman, R. A., & Hasan, H. A. (2022). Effect of hydraulic retention time on the performance of a compact moving bed biofilm reactor for effluent polishing of treated sewage. Water, 14(1), Article 81. https://doi.org/10.3390/w14010081
Kumari, A., Maurya, N. S., & Tiwari, B. (2020). Hospital wastewater treatment scenario around the globe. In R. D. Tyagi, B. Sellamuthu, B. Tiwari, S. Yan, P. Drogui, X. Zhang, & A. Pandey (Eds.). Current developments in biotechnology and bioengineering. Environmental and health impact of hospital wastewater (pp. 549-570). Elsevier. https://doi.org/10.1016/B978-0-12-819722-6.00015-8
Madan, S., Madan, R., & Hussain, A. (2022). Advancement in biological wastewater treatment using hybrid moving bed biofilm reactor (MBBR): A review. Applied Water Science, 12(6), Article 141. https://doi.org/10.1007/s13201-022-01662-y
McQuarrie, J. P., & Boltz, J. P. (2011). Moving bed biofilm reactor technology: Process applications, design, and performance. Water Environment Research, 83(6), 560-575. https://doi.org/10.2175/106143010x12851009156286
Metcalf & Eddy. (2014). Wastewater engineering: Treatment and resource recovery (5th Ed.). McGraw-Hill.
Muttaqin, R., Ratnawati, R., & Slamet, S. (2022). Batch electrocoagulation system using aluminum and stainless steel 316 plates for hospital wastewater treatment. IOP Conference Series: Earth and Environmental Science, 963(1), Article 012056. https://doi.org/10.1088/1755-1315/963/1/012056
Nourredine, H., & Barjenbruch, M. (2024). Graywater treatment efficiency and nutrient removal using moving bed biofilm reactor (MBBR) systems: A comprehensive review. Water, 16(16), Article 2330. https://doi.org/10.3390/w16162330
Pan, D., Shao, S., Zhong, J., Wang, M., & Wu, X. (2022). Performance and mechanism of simultaneous nitrification–denitrification and denitrifying phosphorus removal in long-term moving bed biofilm reactor (MBBR). Bioresource Technology, 348, Article 126726. https://doi.org/10.1016/j.biortech.2022.126726
Ruiz, G., Jeison, D., Rubilar, O., Ciudad, G., & Chamy, R. (2006). Nitrification–denitrification via nitrite accumulation for nitrogen removal from wastewaters. Bioresource Technology, 97(2), 330-335. https://doi.org/10.1016/j.biortech.2005.02.018
Satoh, H., Ono, H., Rulin, B., Kamo, J., Okabe, S., & Fukushi, K.-I. (2004). Macroscale and microscale analyses of nitrification and denitrification in biofilms attached on membrane aerated biofilm reactors. Water Research, 38(6), 1633-1641. https://doi.org/10.1016/j.watres.2003.12.020
Sindhi, Y., & Shah, M. J. (2015). Lab scale study on moving bed biofilm reactor- an effective perspective in biological wastewater treatment. https://www.academia.edu/100528893/Lab_Scale_Study_on_Moving_Bed_Biofilm_Reactor_An_Effective_Perspective_in_Biological_Wastewater_Treatment?uc-sb-sw=111004353
Tchobanoglous, G., Burton, F. L., Stensel, H. D., & Metcalf & Eddy. (2003). Wastewater engineering: Treatment and reuse (4th Ed). McGraw-Hill.
Ugoeze, K., Alalor, C., Ibezim, C., Chinko, B., Owonaro, P., Anie, C., Okoronkwo, N., Mgbahurike, A., Ofomata, C., Alfred-Ugbenbo, D., & Ndukwu, G. (2024). Environmental and human health impact of antibiotics waste mismanagement: A review. Advances in Environmental and Engineering Research, 5(1), Article 005. https://doi.org/10.21926/aeer.2401005
Van Loosdrecht, M. C. M., & Jetten, M. S. M. (1998). Microbiological conversions in nitrogen removal. Water Science and Technology, 38(1), 1-7. https://doi.org/10.1016/S0273-1223(98)00383-7
Verlicchi, P., Galletti, A., Petrovic, M., & BarcelÓ, D. (2010). Hospital effluents as a source of emerging pollutants: An overview of micropollutants and sustainable treatment options. Journal of Hydrology, 389(3-4), 416-428. https://doi.org/10.1016/j.jhydrol.2010.06.005
Wang, J., Yang, D., Qing, Q., Zhang, Y., Zhu, J., & Wang, L. (2024). A study of the system performance and the microbial community composition of chemical wastewater in an AO-MBBR treatment process. Sustainability, 16(9), Article 3625. https://doi.org/10.3390/su16093625
Wang, K.-K., Song, S., Jung, S.-J., Hwang, J.-W., Kim, M.-G., Kim, J.-H., Sung, J., Lee, J.-K., & Kim, Y.-R. (2020). Lifetime and diffusion distance of singlet oxygen in air under everyday atmospheric conditions. Physical Chemistry Chemical Physics, 22(38), 21664-21671. https://doi.org/10.1039/D0CP00739K
Yamagiwa, K., Yoshida, M., Ito, A., & Ohkawa, A. (1998). A new oxygen supply method for simultaneous organic carbon removal and nitrification by a one-stage biofilm process. Water Science and Technology, 37(4), 117-124. https://doi.org/10.1016/S0273-1223(98)00093-6
Zhang, X., Yan, S., Chen, J., Tyagi, R. D., & Li, J. (2020). 3 - Physical, chemical, and biological impact (hazard) of hospital wastewater on environment: Presence of pharmaceuticals, pathogens, and antibiotic-resistance genes. In R. D. Tyagi, B. Sellamuthu, B. Tiwari, S. Yan, P. Drogui, X. Zhang, & A. Pandey (Eds.). Current Developments in Biotechnology and Bioengineering (pp. 79-102). Elsevier. https://doi.org/10.1016/B978-0-12-819722-6.00003-1