Exploring the limits of anaerobic biodegradability of urban wastewater by AnMBR technology

[EN] Anaerobic membrane bioreactors (AnMBRs) can achieve maximum energy recovery from urban wastewater (UWW) by converting influent COD into methane. The aim of this study was to assess the anaerobic biodegradability limits of urban wastewater with AnMBR technology by studying the possible degradation of the organic matter considered as non-biodegradable as observed in aerobic membrane bioreactors operated at very high sludge retention times. For this, the results obtained in an AnMBR pilot plant operated at very high SRT (140 days) treating sulfate-rich urban wastewater were compared with those previously obtained with the system operating at lower SRT (29 to 70 days). At 140 days SRT the organic matter biodegraded by the AnMBR system accounted for 64.4% of the influent COD (45.9% was removed by sulfate reducing bacteria (SRB), and only 18.5% was converted into methane, highlighting the strong competition between SRB and methanogenic archaea (MA) when treating sulfate-rich wastewater). Almost half of the methane produced (46%) was dissolved in the permeate and most of it was recovered by a degassing membrane. The organic matter biodegraded by the AnMBR system was similar to the influent anaerobic biodegradability determined by wastewater characterization assays (68.5% of the influent COD), indicating that nearly all the influent's biodegradable organic matter had been removed. This percentage of degraded COD was similar to that obtained in previous studies working at 70 days SRT, showing that the limit of anaerobic biodegradability was already reached in this SRT. The organic matter considered as non-biodegradable according to wastewater characterization assays therefore was not seen to degrade in the AnMBR pilot plant, even at very high SRT. Once the biodegraded COD is close to the influent's anaerobic biodegradability, increasing the SRT is not justified as it only leads to higher operational costs for the same biogas production. These findings support the use of mathematical models for AnMBR design since they accurately represent the behaviour of these systems in a wide range of operating conditions.This research project was supported by the Spanish Ministry of Economy and Competitiveness (MINECO, Project CTM2014-54980-C2-2-R). The authors are also grateful for the support received from the Generalitat Valenciana via CPI-16-155 fellowships.Seco Torrecillas, A.; Mateo-Llosa, O.; Zamorano-López, N.; Sanchis-Perucho, P.; Serralta Sevilla, J.; Martí Ortega, N.; Borrás Falomir, L.... (2018). Exploring the limits of anaerobic biodegradability of urban wastewater by AnMBR technology. Environmental Science: Water Research & Technology. 4(11):1877-1887. https://doi.org/10.1039/c8ew00313kS18771887411Li, W.-W., & Yu, H.-Q. (2011). From wastewater to bioenergy and biochemicals via two-stage bioconversion processes: A future paradigm. Biotechnology Advances, 29(6), 972-982. doi:10.1016/j.biotechadv.2011.08.012Shin, C., & Bae, J. (2018). Current status of the pilot-scale anaerobic membrane bioreactor treatments of domestic wastewaters: A critical review. Bioresource Technology, 247, 1038-1046. doi:10.1016/j.biortech.2017.09.002EEA , Performance of water utilities beyond compliance (Technical report No. 5/2014) , Luxemburg , 2014Martin, I., Pidou, M., Soares, A., Judd, S., & Jefferson, B. (2011). Modelling the energy demands of aerobic and anaerobic membrane bioreactors for wastewater treatment. 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Dissolved methane recovery from anaerobic effluents using hollow fibre membrane contactors. Journal of Membrane Science, 502, 141-150. doi:10.1016/j.memsci.2015.12.037Hatamoto, M., Yamamoto, H., Kindaichi, T., Ozaki, N., & Ohashi, A. (2010). Biological oxidation of dissolved methane in effluents from anaerobic reactors using a down-flow hanging sponge reactor. Water Research, 44(5), 1409-1418. doi:10.1016/j.watres.2009.11.021Pretel, R., Robles, A., Ruano, M. V., Seco, A., & Ferrer, J. (2013). Environmental impact of submerged anaerobic MBR (SAnMBR) technology used to treat urban wastewater at different temperatures. Bioresource Technology, 149, 532-540. doi:10.1016/j.biortech.2013.09.060Lubello, C., Caffaz, S., Gori, R., & Munz, G. (2009). A modified Activated Sludge Model to estimate solids production at low and high solids retention time. Water Research, 43(18), 4539-4548. doi:10.1016/j.watres.2009.08.001L. Cabrera , F.García-Usach , J.Ribes , A.Seco , J. J.Morenilla , F.Llavador and J.Ferrer , Estudio de la producción de fangos en bioreactores de membranas aerobios con elevados valores de tiempo de retención celular, Fangos y lodos , 2009 , vol. 7 , pp. 1–3Giménez, J. B., Robles, A., Carretero, L., Durán, F., Ruano, M. V., Gatti, M. N., … Seco, A. (2011). Experimental study of the anaerobic urban wastewater treatment in a submerged hollow-fibre membrane bioreactor at pilot scale. Bioresource Technology, 102(19), 8799-8806. doi:10.1016/j.biortech.2011.07.014Robles, Á., Durán, F., Ruano, M. V., Ribes, J., Rosado, A., Seco, A., & Ferrer, J. (2015). Instrumentation, control, and automation for submerged anaerobic membrane bioreactors. Environmental Technology, 36(14), 1795-1806. doi:10.1080/09593330.2015.1012180R. E. Moosbrugger , M. C.Wentzel , G. A.Ekama and G. 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The Domain-specific Probe EUB338 is Insufficient for the Detection of all Bacteria: Development and Evaluation of a more Comprehensive Probe Set. Systematic and Applied Microbiology, 22(3), 434-444. doi:10.1016/s0723-2020(99)80053-8C. W. Gellings and K. E.Parmenter , Energy efficiency in fertilizer production and use. In Knowledge for Sustainable Development , Encyclopedia of Life Support Systems (EOLSS), Eolss Publisher , Oxford , 2004 , vol. II , pp. 419–450J. B. Giménez , Estudio del tratamiento anaerobio de aguas residuales urbanas en biorreactores de membrana (Doctoral Thesis) , Universitat de València , Valencia , 2014Giménez, J. B., Martí, N., Robles, A., Ferrer, J., & Seco, A. (2014). Anaerobic treatment of urban wastewater in membrane bioreactors: evaluation of seasonal temperature variations. Water Science and Technology, 69(7), 1581-1588. doi:10.2166/wst.2014.069Robles, A., Ruano, M. V., Ribes, J., & Ferrer, J. (2012). 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Resource recovery from sulphate-rich sewage through an innovative anaerobic-based water resource recovery facility (WRRF)

[EN] This research work proposes an innovative water resource recovery facility (WRRF) for the recovery of energy, nutrients and reclaimed water from sewage, which represents a promising approach towards enhanced circular economy scenarios. To this aim, anaerobic technology, microalgae cultivation, and membrane technology were combined in a dedicated platform. The proposed platform produces a high-quality solid- and coliform-free effluent that can be directly discharged to receiving water bodies identified as sensitive areas. Specifically, the content of organic matter, nitrogen and phosphorus in the effluent was 45 mg COD.L-1 , 14.9 mg N.L-1 and 0.5 mg P.L-1 , respectively. Harvested solar energy and carbon dioxide biofixation in the form of microalgae biomass allowed remarkable methane yields (399 STP L CH 4.kg(-1) CODinf ) to be achieved, equivalent to theoretical electricity productions of around 0.52 kWh per m 3 of wastewater entering the WRRF. Furthermore, 26.6% of total nitrogen influent load was recovered as ammonium sulphate, while nitrogen and phosphorus were recovered in the biosolids produced (650 +/- 77 mg N.L-1 and 121.0 +/- 7.2 mg P.L-1).This research was supported by the Spanish Ministry of Economy and Competitiveness (MINECO, Projects CTM2014-54980-C2-1-R and CTM2014-54980-C2-2-R) jointly with the European Regional Development Fund (ERDF), which are gratefully acknowledged. This research was also supported by the Spanish Ministry of Education, Culture and Sport via two pre-doctoral FPU fellowships (FPU14/05082 and FPU15/02595) and by the Spanish Ministry of Economy and Competitiveness via two pre-doctoral FPI fellowships (BES-2015-071884, BES-2015-073403) and one Juan de la Cierva contract (FJCI-2014-21616). The authors would also like to acknowledge the support received from Generalitat Valenciana via two VALithornd post-doctoral grants (APOSTD/2014/049 and APOSTD/2016/104) and via the fellowships APOTI/2016/059 and CPI-16-155, as well as the financial aid received from the European Climate KIC association for the 'MAB 2.0' Project (APIN0057_ 2015-3.6-230_ P066-05) and Universitat Politecnica de Valencia via a pre-doctoral FPI fellowship to the seventh author.Seco Torrecillas, A.; Aparicio Antón, SE.; Gonzalez-Camejo, J.; Jiménez Benítez, AL.; Mateo-Llosa, O.; Mora-Sánchez, JF.; Noriega-Hevia, G.... (2018). Resource recovery from sulphate-rich sewage through an innovative anaerobic-based water resource recovery facility (WRRF). Water Science & Technology. 78(9):1925-1936. https://doi.org/10.2166/wst.2018.492S19251936789Bair, R. A., Ozcan, O. O., Calabria, J. L., Dick, G. H., & Yeh, D. H. (2015). Feasibility of anaerobic membrane bioreactors (AnMBR) for onsite sanitation and resource recovery (nutrients, energy and water) in urban slums. Water Science and Technology, 72(9), 1543-1551. doi:10.2166/wst.2015.349Barat, R., Serralta, J., Ruano, M. V., Jiménez, E., Ribes, J., Seco, A., & Ferrer, J. (2013). Biological Nutrient Removal Model No. 2 (BNRM2): a general model for wastewater treatment plants. Water Science and Technology, 67(7), 1481-1489. doi:10.2166/wst.2013.004Batstone, D. J., Hülsen, T., Mehta, C. M., & Keller, J. (2015). Platforms for energy and nutrient recovery from domestic wastewater: A review. Chemosphere, 140, 2-11. doi:10.1016/j.chemosphere.2014.10.021Bilad, M. R., Arafat, H. A., & Vankelecom, I. F. J. (2014). Membrane technology in microalgae cultivation and harvesting: A review. Biotechnology Advances, 32(7), 1283-1300. doi:10.1016/j.biotechadv.2014.07.008Carrington E.-G. 2001 Evaluation of Sludge Treatments for Pathogen Reduction. http://europa.eu.int/comm/environment/pubs/home.htm.Cookney, J., Mcleod, A., Mathioudakis, V., Ncube, P., Soares, A., Jefferson, B., & McAdam, E. J. (2016). Dissolved methane recovery from anaerobic effluents using hollow fibre membrane contactors. Journal of Membrane Science, 502, 141-150. doi:10.1016/j.memsci.2015.12.037De Morais, M. G., & Costa, J. A. V. (2007). Biofixation of carbon dioxide by Spirulina sp. and Scenedesmus obliquus cultivated in a three-stage serial tubular photobioreactor. Journal of Biotechnology, 129(3), 439-445. doi:10.1016/j.jbiotec.2007.01.009Giménez, J. B., Robles, A., Carretero, L., Durán, F., Ruano, M. V., Gatti, M. N., … Seco, A. (2011). Experimental study of the anaerobic urban wastewater treatment in a submerged hollow-fibre membrane bioreactor at pilot scale. Bioresource Technology, 102(19), 8799-8806. doi:10.1016/j.biortech.2011.07.014Giménez, J. B., Martí, N., Ferrer, J., & Seco, A. (2012). Methane recovery efficiency in a submerged anaerobic membrane bioreactor (SAnMBR) treating sulphate-rich urban wastewater: Evaluation of methane losses with the effluent. Bioresource Technology, 118, 67-72. doi:10.1016/j.biortech.2012.05.019Giménez, J. B., Bouzas, A., Carrere, H., Steyer, J.-P., Ferrer, J., & Seco, A. (2018). Assessment of cross-flow filtration as microalgae harvesting technique prior to anaerobic digestion: Evaluation of biomass integrity and energy demand. Bioresource Technology, 269, 188-194. doi:10.1016/j.biortech.2018.08.052González-Camejo, J., Serna-García, R., Viruela, A., Pachés, M., Durán, F., Robles, A., … Seco, A. (2017). Short and long-term experiments on the effect of sulphide on microalgae cultivation in tertiary sewage treatment. Bioresource Technology, 244, 15-22. doi:10.1016/j.biortech.2017.07.126Martí, N., Barat, R., Seco, A., Pastor, L., & Bouzas, A. (2017). Sludge management modeling to enhance P-recovery as struvite in wastewater treatment plants. Journal of Environmental Management, 196, 340-346. doi:10.1016/j.jenvman.2016.12.074Moosbrugger R. , WentzelM. & EkamaG.1992Simple Titration Procedures to Determine H2CO3 Alkalinity and Short-chain Fatty Acids in Aqueous Solutions Containing Known Concentrations of Ammonium, Phosphate and Sulphide Weak Acid/Bases. Water. Res. Commission, Report, No. TT 57/92.Morales, N., Boehler, M., Buettner, S., Liebi, C., & Siegrist, H. (2013). Recovery of N and P from Urine by Struvite Precipitation Followed by Combined Stripping with Digester Sludge Liquid at Full Scale. Water, 5(3), 1262-1278. doi:10.3390/w5031262Pretel, R., Durán, F., Robles, A., Ruano, M. V., Ribes, J., Serralta, J., & Ferrer, J. (2015). Designing an AnMBR-based WWTP for energy recovery from urban wastewater: The role of primary settling and anaerobic digestion. Separation and Purification Technology, 156, 132-139. doi:10.1016/j.seppur.2015.09.047Pretel, R., Robles, A., Ruano, M. V., Seco, A., & Ferrer, J. (2016). Economic and environmental sustainability of submerged anaerobic MBR-based (AnMBR-based) technology as compared to aerobic-based technologies for moderate-/high-loaded urban wastewater treatment. Journal of Environmental Management, 166, 45-54. doi:10.1016/j.jenvman.2015.10.004Sharma, B., Sarkar, A., Singh, P., & Singh, R. P. (2017). Agricultural utilization of biosolids: A review on potential effects on soil and plant grown. Waste Management, 64, 117-132. doi:10.1016/j.wasman.2017.03.002Sialve, B., Bernet, N., & Bernard, O. (2009). Anaerobic digestion of microalgae as a necessary step to make microalgal biodiesel sustainable. 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Maximizing resource recovery from urban wastewater through an innovative facility layout

[EN] This research work proposes an innovative layout for urban wastewater treatment based on anaerobic technology, microalgal cultivation and membrane technology. The proposed Water Resource Recovery Facility (WRRF) system can treat urban wastewater efficiently, complying with legal discharge limits and allowing for resource recovery, i.e. energy, nutrients and reclaimed water. In addition, the proposed layout produces less solid wastes than a conventional wastewater treatment plant (WWTP) and it is possible to recover energy as biogas, not only from the original wastewater sources but also from the biomass generated in the WRRF system

Experimental sulphide inhibition calibration method in nitrification processes: A case-study

[EN] Sulphide is one of the inhibitors in the nitrification process in WWTP in regions with sulphate rich soils. As little information is currently available on sulphide nitrification inhibition, the aim of this study was to develop a method based on a modification of the Successive Additions Method to calibrate the effect of sulphide on the activity of ammonia-oxidising bacteria (AOB) and nitrite-oxidising bacteria (NOB). The developed method was then applied to activated sludge samples from two WWTPs with different influent sulphide concentrations. In both cases, sulphide had a greater inhibitory effect on NOB than AOB activity. The sulphide inhibition was found to be lower in the activated sludge fed with sulphide-rich wastewater. The AOB and NOB activity measured at different sulphide concentrations could be accurately modelled with the Hill inhibition equation.This research was supported by Universitat Politècnica de València via FPI fellowship for the first author and by the Spanish Ministry of Science and Innovation via a pre-doctoral FPI fellowship (BES-2015-073403) for the second author.Noriega-Hevia, G.; Mateo-Llosa, O.; Maciá, A.; Lardín, C.; Pastor, L.; Serralta Sevilla, J.; Bouzas, A. (2020). Experimental sulphide inhibition calibration method in nitrification processes: A case-study. Journal of Environmental Management. 274:1-7. https://doi.org/10.1016/j.jenvman.2020.111191S17274Arp, D., Sayavedra-Soto, L., & Hommes, N. (2002). Molecular biology and biochemistry of ammonia oxidation by Nitrosomonas europaea. Archives of Microbiology, 178(4), 250-255. doi:10.1007/s00203-002-0452-0Bejarano-Ortiz, D. I., Huerta-Ochoa, S., Thalasso, F., Cuervo-López, F. de M., & Texier, A.-C. (2015). Kinetic Constants for Biological Ammonium and Nitrite Oxidation Processes Under Sulfide Inhibition. Applied Biochemistry and Biotechnology, 177(8), 1665-1675. doi:10.1007/s12010-015-1844-3Bejarano Ortiz, D. I., Thalasso, F., Cuervo López, F. de M., & Texier, A.-C. (2012). Inhibitory effect of sulfide on the nitrifying respiratory process. Journal of Chemical Technology & Biotechnology, 88(7), 1344-1349. doi:10.1002/jctb.3982Beristain-Cardoso, R., Gómez, J., & Méndez-Pampín, R. (2010). The behavior of nitrifying sludge in presence of sulfur compounds using a floating biofilm reactor. Bioresource Technology, 101(22), 8593-8598. doi:10.1016/j.biortech.2010.06.084Choi, O., Das, A., Yu, C.-P., & Hu, Z. (2010). Nitrifying bacterial growth inhibition in the presence of algae and cyanobacteria. Biotechnology and Bioengineering, 107(6), 1004-1011. doi:10.1002/bit.22860Claros, J., Jiménez, E., Borrás, L., Aguado, D., Seco, A., Ferrer, J., & Serralta, J. (2010). Short-term effect of ammonia concentration and salinity on activity of ammonia oxidizing bacteria. Water Science and Technology, 61(12), 3008-3016. doi:10.2166/wst.2010.217Delgado Vela, J., Dick, G. J., & Love, N. G. (2018). Sulfide inhibition of nitrite oxidation in activated sludge depends on microbial community composition. Water Research, 138, 241-249. doi:10.1016/j.watres.2018.03.047Kapoor, V., Elk, M., Li, X., Impellitteri, C. A., & Santo Domingo, J. W. (2016). Effects of Cr(III) and Cr(VI) on nitrification inhibition as determined by SOUR, function-specific gene expression and 16S rRNA sequence analysis of wastewater nitrifying enrichments. Chemosphere, 147, 361-367. doi:10.1016/j.chemosphere.2015.12.119Moussa, M. S., Lubberding, H. J., Hooijmans, C. M., van Loosdrecht, M. C. M., & Gijzen, H. J. (2003). Improved method for determination of ammonia and nitrite oxidation activities in mixed bacterial cultures. Applied Microbiology and Biotechnology, 63(2), 217-221. doi:10.1007/s00253-003-1360-1Sánchez-Ramírez, J. E., Seco, A., Ferrer, J., Bouzas, A., & García-Usach, F. (2015). Treatment of a submerged anaerobic membrane bioreactor (SAnMBR) effluent by an activated sludge system: The role of sulphide and thiosulphate in the process. Journal of Environmental Management, 147, 213-218. doi:10.1016/j.jenvman.2014.04.043Sears, K., Alleman, J. E., Barnard, J. L., & Oleszkiewicz, J. A. (2004). Impacts of reduced sulfur components on active and resting ammonia oxidizers. Journal of Industrial Microbiology & Biotechnology, 31(8), 369-378. doi:10.1007/s10295-004-0157-2Subbarao, G. V., Kishii, M., Nakahara, K., Ishikawa, T., Ban, T., Tsujimoto, H., … Ito, O. (2009). Biological nitrification inhibition (BNI)-Is there potential for genetic interventions in the Triticeae? Breeding Science, 59(5), 529-545. doi:10.1270/jsbbs.59.529Tang, H. L., & Chen, H. (2015). Nitrification at full-scale municipal wastewater treatment plants: Evaluation of inhibition and bioaugmentation of nitrifiers. Bioresource Technology, 190, 76-81. doi:10.1016/j.biortech.2015.04.063Urgun-Demirtas, M., Pagilla, K. R., Kunetz, T. E., Sobanski, J. P., & Law, K. P. (2008). Nutrient removal process selection for planning and design of large wastewater treatment plant upgrade needs. Water Science and Technology, 57(9), 1345-1348. doi:10.2166/wst.2008.223Wan, Z., Li, M., Bao, Y., & Jiang, Y. (2017). Study on the effect of sulfate in the treatment of high ammonia organic wastewater. DESALINATION AND WATER TREATMENT, 98, 98-107. doi:10.5004/dwt.2017.21674Wang, F., Ding, Y., Ge, L., Ren, H., & Ding, L. (2010). Effect of high-strength ammonia nitrogen acclimation on sludge activity in sequencing batch reactor. Journal of Environmental Sciences, 22(11), 1683-1688. doi:10.1016/s1001-0742(09)60306-