Alternatives for the management of pig slurry: Phosphorous recovery and biogas generation

[EN] Pig slurry is highly polluted waste stream characterized by its high nutrients content and its high organic matter concentration. In this research, two alternatives in the management of this wastewater were studied. On the one hand, removal of nutrients from piggery wastewater by struvite precipitation was evaluated. Different molar ratios Mg+2/PO4-3, pH and temperatures were tested. On the other hand, an anaerobic treatment was performed with and without previous struvite crystallization and the methane production was analyzed. Results showed that the optimal experimental conditions to achieve the highest ammonium nitrogen and phosphate removal percentages (62.01% and 66.96%, respectively) were a molar concentration ratio (Mg+2/PO4-3) of 2.8, pH of 10 and temperature of 22 degrees C. In addition, images from FE-SEM microscopy demonstrated that the struvite morphology was orthorhombic. Concerning the anaerobic digestion, the chemical oxygen demand removal efficiencies were 59.87% and 52.25% for the treatment without previous struvite precipitation and with previous struvite precipitation, respectively. Furthermore, the maximum biogas potential was found when no previous struvite precipitation was carried out, with a biogas generation around 4 mLh(-1) and a percentage of methane in the biogas between 32.37 and 59.73%.The authors wish to gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the project PROVIP.ES (RTC-2014-2239-2).Lujan Facundo, MJ.; Iborra-Clar, MI.; Mendoza Roca, JA.; Also Jesús, M. (2019). Alternatives for the management of pig slurry: Phosphorous recovery and biogas generation. Journal of Water Process Engineering. 30:1-7. https://doi.org/10.1016/j.jwpe.2017.08.011S173

Pharmaceutical compounds removal by adsorption with commercial and reused carbon coming from a drinking water treatment plant

[EN] The concern for the presence of pharmaceutical compounds in purified wastewater has grown in recent years. In this context, efficient and economically viable processes are required for their removal. In this study, adsorption was conducted to assess the removal of ibuprofen, caffeine, diazepam and acetaminophen, both as separated processes as in combination with a biological process in sequencing batch reactors. Removal efficiencies of these pharmaceutical active compounds were evaluated using two commercial activated carbons in granular and powder form and a discarded (after its use) activated carbon from a drinking water treatment plant. Concerning the biological treatment tests, simulated municipal wastewater was doped with 3¿mg/L of each pharmaceutical active compounds. Results showed that caffeine, acetaminophen and ibuprofen achieved excellent removal percentages, even without powder activated carbon addition (more than 94%); By contrast, whereas diazepam removal was low (lower than 50%); however, it was improved up to 68% with the powder activated carbon addition to the sequencing batch reactors. Regarding adsorption tests as separated process, ibuprofen was the pharmaceutical active compounds with the lowest removal percentage (around 50% for the granular activated carbon) and diazepam (around 80% for the granular activated carbon) was the compound with the maximum removal efficiency for the tested concentrations (between 0.5 and 3¿mg/L). Finally, results were very promising for the reused activated carbon since the removal efficiency of the pharmaceutical active compounds was higher than 90% (except for ibuprofen) when 0.5¿g/L of reused activated carbon was applied in powder form to solutions of 3¿mg/L of each pharmaceutical active compounds. In this way, a low cost activated carbon could be applied in wastewater treatment plants for pharmaceutical active compounds removal.This work has been carried out in the frame of the project IMIDTA/2017/73 granted to the company GECIVAL, S.L. by Instituto Valenciano de Competitividad Empresarial (IVACE) within the program for research and development projects for SMEs. This project has been co-financed (50%) by the operational program FEDER of Comunitat Valenciana 2014 2020.Lujan Facundo, MJ.; Iborra-Clar, MI.; Mendoza Roca, JA.; Alcaina-Miranda, MI. (2019). Pharmaceutical compounds removal by adsorption with commercial and reused carbon coming from a drinking water treatment plant. Journal of Cleaner Production. 238:1-9. https://doi.org/10.1016/j.jclepro.2019.117866S1923

Simultaneous concentration of nutrients from anaerobically digested sludge centrate and pre-treatment of industrial effluents by forward osmosis

[EN] In the last years, forward osmosis (FO) has gained increasing prominence, new membranes are being developed and new applications are being considered. In this study, the recovery of nitrogen and phosphorus of the anaerobically digested sludge centrate was studied by FO using two industrial effluents characterized by high osmotic pressure (residual stream from an absorption process for ammonia elimination and brine from a seawater desalination facility) as draw solutions. The experiments were carried out in a laboratory plant testing two FO membranes (CTA-NW and Aquaporin Inside membrane). Results showed that nitrogen concentration was achieved with both membranes and both draw solutions. The use of the effluent from ammonia absorption enhanced of the nitrogen concentration in the feed stream to the FO membrane. The reached concentration factor in the laboratory tests was 1.61 when Aquaporin membrane was used. Phosphorus could not be concentrated because of its precipitation as calcium phosphate (confirmed by EDX analysis) as a consequence of the high calcium concentration of the municipal wastewater.This study was supported by the Spanish Ministry of Economy and Competitiveness through the project RTC-2015-3582-5-AR.Soler Cabezas, JL.; Mendoza Roca, JA.; Vincent Vela, MC.; Lujan Facundo, MJ.; Pastor Alcañiz, L. (2018). Simultaneous concentration of nutrients from anaerobically digested sludge centrate and pre-treatment of industrial effluents by forward osmosis. Separation and Purification Technology. 193:289-296. https://doi.org/10.1016/j.seppur.2017.10.058S28929619

A comparative study of the influence of salt concentration on the performance of an osmotic membrane bioreactor and a sequencing batch reactor

[EN] BACKGROUNDAn osmotic membrane bioreactor (OMBR) is a wastewater treatment technique that presents low energy requirements, low membrane fouling and high removal of nutrients and organic matter. However, reverse salt flux is the main disadvantage because it causes conductivity increase in the bioreactor. This study compares the performance of a sequencing batch reactor (SBR) and an OMBR in terms of chemical oxygen demand (COD) removal, soluble microbial products (SMP) and extracellular polymeric substances (EPS) production. For that, the influent conductivity in the SBR was increased as this increases conductivity in the osmotic membrane bioreactor. RESULTSComparing the results obtained at two mixed liquor suspended solids (MLSS) concentrations in terms of membrane fouling, a concentration of 5 g L-1 of MLSS was chosen for the comparison with the SBR. The SBR achieved slightly higher COD removal efficiencies than the OMBR is spite of the accumulation of cellular debris in the membrane bioreactor. The accumulation of SMP and EPS in the OMBR was also higher than in the SBR due to the cellular debris and organic matter accumulation. In both reactors the microbial activity measured in terms of standard oxygen uptake rate decreased due to the increase of salt concentration in the bioreactor. CONCLUSIONSAs a conclusion, OMBR will be especially feasible when the draw solution is a residual stream of the same industry, like tannery wastewater or table olive processing. (c) 2017 Society of Chemical IndustryThis study was supported by the Spanish Ministry of Economy and Competitiveness through the project RTC-2015-3582-5-AR.Soler Cabezas, JL.; Lujan Facundo, MJ.; Mendoza Roca, JA.; Vincent Vela, MC.; Pastor Alcañiz, L. (2018). A comparative study of the influence of salt concentration on the performance of an osmotic membrane bioreactor and a sequencing batch reactor. Journal of Chemical Technology & Biotechnology. 93(1):72-79. https://doi.org/10.1002/jctb.5321S727993

Low-cost ceramic membranes manufacture using INKJET technology for active layer deposition and validation on membrane bioreactors

[EN] The fabrication of eco-friendly ceramic membranes based on low-cost raw materials, using digital INKJET printing techniques for active layer deposition and its validation in a membrane bioreactor (MBR) has been studied. The raw materials used in the manufacture of the support layer were UA50/2 clay, chamotte, calcium carbonate and potato starch. A MBR laboratory plant was operated to treat municipal wastewater with three ceramic membranes with different grammages in the selective layer deposition. The membrane performance at laboratory scale was evaluated in terms of transmembrane pressure (TMP) evolution for a constant permeate flux, permeate quality and mixed liquor characteristics. From these experiments, it was selected the membrane which obtained the lowest TMP profile maintaining appropriate water quality parameters (chemical oxygen demand (COD) removal percentage around 90% and turbidity around 0.06 NTU). This membrane was also operated at pilot plant scale in order to validate it at higher scale. Results indicated that TMP values were in the range of 0.06 and 0.1 bar, COD removal percentage was around 98% and microbiology analysis demonstrated that the quality of the effluent, according to European regulation 2020/741, can be classified as Class A and it can be reused for non-potable purposes.Authors thank the FEDER/Ministerio de Ciencia, Innovacion y Universidades-Agencia Estatal de Investigacion for the financial support (Reference of the project: RTC-2017-5897-5-AR).Lujan Facundo, MJ.; Mendoza Roca, JA.; Bes-Piá, M.; Zuriaga-Agusti, E.; Mestre, S.; Palacios, M. (2023). Low-cost ceramic membranes manufacture using INKJET technology for active layer deposition and validation on membrane bioreactors. Process Safety and Environmental Protection. 176:618-626. https://doi.org/10.1016/j.psep.2023.06.04561862617

The role of salinity on the changes of the biomass characteristics and on the performance of an OMBR treating tannery wastewater

[EN] Tannery wastewaters are difficult to treat biologically due to the high salinity and organic matter concentration. Conventional treatments, like sequential batch reactors (SBR) and membrane bioreactors (MBR), have showed settling problems, in the case of SBR, and ultrafiltration (UF) membrane fouling in the case of MBR, slowing their industrial application. In this work, the treatment of tannery wastewater with an osmotic membrane bioreactor (OMBR) is assessed. Forward osmosis (FO) membranes are characterized by a much lower fouling degree than UF membranes. The permeate passes through the membrane pores (practically only water by the high membrane rejection) from the feed solution to the draw solution, which is also an industrial wastewater (ammonia absorption effluent) in this work. Experiments were carried out at laboratory scale with a FO CTA-NW membrane from Hydration Technology Innovations (HTI). Tannery wastewater was treated by means of an OMBR using as DS an actual industrial wastewater mainly consisting of ammonium sulphate. The monitoring of the biological process was carried out with biological indicators like microbial hydrolytic enzymatic activities, dissolved and total adenosine triphosphate (ATP) in the mixed liquor and microbial population. Results indicated a limiting conductivity in the reactor of 35 mS cm(-1) (on the 43th operation day), from which process was deteriorated. This process performance diminution was associated by a high decrease of the dehydrogenase activity and a sudden increase of the protease and lipase activities. The increase of the bacterial stress index also described appropriately the process performance. Regarding the relative abundance of bacterial phylotypes, 37 phyla were identified in the biomass. Proteobacteria were the most abundant (varying the relative abundance between 50.29% and 34.78%) during the first 34 days of operation. From this day on, Bacteroidetes were detected in a greater extent varying the relative abundance of this phylum between 27.20% and 40.45%. (C) 2018 Elsevier Ltd. All rights reserved.This study was supported by the Spanish Ministry of Economy and Competitiveness through the project RTC-2015-3582-5-AR.Lujan Facundo, MJ.; Fernández-Navarro, J.; Alonso Molina, JL.; Amoros, I.; Moreno Trigos, MY.; Mendoza Roca, JA.; Pastor Alcañiz, L. (2018). The role of salinity on the changes of the biomass characteristics and on the performance of an OMBR treating tannery wastewater. Water Research. 142:129-137. https://doi.org/10.1016/j.watres.2018.05.046S12913714

Preparation of Sewage Sludge¿Based Activated Carbon for Hydrogen Sulphide Removal

[EN] The circular economy concept boosts the use of wastes as secondary raw materials in the EU renewable and sustainable framework. In wastewater treatment plants (WWTP), sludge is one of the most important wastes, and its management is being widely discussed in the last years. In this work, sewage sludge from WWTP was employed as raw material for producing activated carbon (AC) by physical-chemical activation. The prepared AC was subsequently tested for hydrogen sulphide removal in view of its further use in deodorization in a WWTP. The effects of the activation temperature and the chemical agent used (NaOH and KOH) during the activation process were studied. On the one hand, the characteristics of each AC fabricated were analysed in terms of BET (Brunauer-Emmett-Teller) surface area, pore and micropore volume, pore diameter, surface morphology and zeta potential. On the other hand, BET isotherms were also calculated. Finally, both the prepared AC and a commercial AC were tested for H2S removal from a gas stream. Results demonstrated that the optimum physical and chemical activation temperature was 600 degrees C and 1000 degrees C, respectively, and the best activated agent tested was KOH. The prepared AC showed excellent properties (specific surface area around 300 m(2)/g) for H2S removal, even better efficiencies than those achieved by the tested commercial AC.Lujan Facundo, MJ.; Iborra-Clar, MI.; Mendoza Roca, JA.; Alcaina-Miranda, MI.; Maciá, AM.; Lardin, C.; Pastor, L.... (2020). Preparation of Sewage Sludge¿Based Activated Carbon for Hydrogen Sulphide Removal. Water Air & Soil Pollution. 231(4):1-12. https://doi.org/10.1007/s11270-020-04518-wS1122314Andrade, S. N., Veloso, C. M., Fontan, R. C. I., Bonomo, R. C. F., Santos, L. S., Brito, M. J. P., & Diniz, G. A. (2018). 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H., Heo, J. E., Kim, K. D., & Huang, C. P. (2019). The adsorption characteristics of fluoride on commercial activated carbon treated with quaternary ammonium salts (Quats). Science of the Total Environment, 693, 133605.Cheng, S., Zhang, L., Ma, A., Xia, H., Peng, J., Li, C., & Shu, J. (2018). Comparison of activated carbon and iron/cerium modified activated carbon to remove methylene blue from wastewater. Journal of Environmental Sciences, 65, 92–102.Chiavola, A. (2013). Textiles. Water Environment Research, 85, 1581–1600.De Falco, G., Montagnaro, F., Balsamo, M., Erto, A., Deorsola, F. A., Lisi, L., & Cimino, S. (2018). Synergic effect of Zn and Cu oxides dispersed on activated carbon during reactive adsorption of H 2 S at room temperature. Microporous and Mesoporous Materials, 257, 135–146.Dias, J. M., Alvim-Ferraz, M. C. M., Almeida, M. F., Rivera-Utrilla, J., & Sánchez-Polo, M. (2007). Waste materials for activated carbon preparation and its use in aqueous-phase treatment: a review. Journal of Environmental Management, 85, 833–846.Donald, J., Ohtsuka, Y., & Xu, C. C. (2011). Effects of activation agents and intrinsic minerals on pore development in activated carbons derived from a Canadian peat. Materials Letters, 65, 744–747.dos Reis, G. S., Mahbub, M. K. B., Wilhelm, M., Lima, E. C., Sampaio, C. H., Saucier, C., & Dias, S. L. P. (2016). Activated carbon from sewage sludge for removal of sodium diclofenac and nimesulide from aqueous solutions. Korean Journal of Chemical Engineering, 33(11), 3149–3161.Hadi, P., Xu, M., Ning, C., Lin, C. S. K., & McKay, G. (2015). A critical review on preparation, characterization and utilization of sludge-derived activated carbons for wastewater treatment. Chemical Engineering Journal, 260, 895–906.Kacan, E. (2016). Optimum BET surface areas for activated carbon produced from textile sewage sludges and its application as dye removal. Journal of Environmental Management, 166, 116–123.Kazak, O., Eker, Y. R., Bingol, H., & Tor, A. (2018). Preparation of chemically-activated high surface area carbon from waste vinasse and its efficiency as adsorbent material. Journal of Molecular Liquids, 272, 189–197.Kimura, K., Honoki, D., & Sato, T. (2017). Effective physical cleaning and adequate membrane flux for direct membrane filtration (DMF) of municipal wastewater: up-concentration of organic matter for efficient energy recovery. Separation and Purification Technology, 181, 37–43.Kuroda, S., Nagaishi, T., Kameyama, M., Koido, K., Seo, Y., & Dowaki, K. (2018). Hydroxyl aluminium silicate clay for biohydrogen purification by pressure swing adsorption: Physical properties, adsorption isotherm, multicomponent breakthrough curve modelling, and cycle simulation. International Journal of Hydrogen Energy, 43, 16573–16588.Ladavos, A. K., Katsoulidis, A. P., Iosifidis, A., Triantafyllidis, K. S., Pinnavaia, T. J., & Pomonis, P. J. (2012). The BET equation, the inflection points of N2 adsorption isotherms and the estimation of specific surface area of porous solids. Microporous and Mesoporous Materials, 151, 126–133.Lapham, D. P., & Lapham, J. L. (2017). Gas adsorption on commercial magnesium stearate: effects of degassing conditions on nitrogen BET surface area and isotherm characteristics. International Journal of Pharmaceutics, 530, 364–376.Li, W. H., Yue, Q. Y., Gao, B. Y., Ma, Z. H., Li, Y. J., & Zhao, H. X. (2011). Preparation and utilization of sludge-based activated carbon for the adsorption of dyes from aqueous solutions. Chemical Engineering Journal, 171, 320–327.Li, F., Lei, T., Zhang, Y., Wei, J., & Yang, Y. (2015). Preparation, characterization of sludge adsorbent and investigations on its removal of hydrogen sulfide under room temperature. Frontiers of Environmental Science & Engineering, 9(2), 190–196.Li, J., Xing, X., Li, J., Shi, M., Lin, A., Xu, C., Zheng, J., & Li, R. (2018). Preparation of thiol-functionalized activated carbon from sewage sludge with coal blending for heavy metal removal from contaminated water. Environmental Pollution, 234, 677–683.Li, D., Zhou, J., Wang, Y., Tian, Y., Wei, L., Zhang, Z., Qiao, Y., & Li, J. (2019). Effects of activation temperature on densities and volumetric CO2 adsorption performance of alkali-activated carbons. Fuel, 238, 232–239.Li, Y. H., Chang, F. M., Huang, B., Song, Y. P., Zhao, H. Y., & Wang, K. J. (2020). Activated carbon preparation from pyrolysis char of sewage sludge and its adsorption performance for organic compounds in sewage. Fuel, 266, 117053.Mininni, G., Blanch, A. R., Lucena, F., & Berselli, S. (2015). EU policy on sewage sludge utilization and perspectives on new approaches of sludge management. Environmental Science and Pollution Research, 22, 7361–7374.Pandiarajan, A., Kamaraj, R., Vasudevan, S., & Vasudevan, S. (2018). OPAC (orange peel activated carbon) derived from waste orange peel for the adsorption of chlorophenoxyacetic acid herbicides from water: adsorption isotherm, kinetic modelling and thermodynamic studies. Bioresource Technology, 261, 329–341.Peng, L., Dai, H., Wu, Y., Peng, Y., & Lu, X. (2018). A comprehensive review of the available media and approaches for phosphorus recovery from wastewater. Water, Air, and Soil Pollution, 229.Pezoti, O., Cazetta, A. L., Bedin, K. C., Souza, L. S., Martins, A. C., Silva, T. L., Santos Júnior, O. O., Visentainer, J. V., & Almeida, V. C. (2016). NaOH-activated carbon of high surface area produced from guava seeds as a high-efficiency adsorbent for amoxicillin removal: kinetic, isotherm and thermodynamic studies. Chemical Engineering Journal, 288, 778–788.Ping, Q., Zheng, M., Dai, X., & Li, Y. (2020). Metagenomic characterization of the enhanced performance of anaerobic fermentation of waste activated sludge with CaO2 addition at ambient temperature: fatty acid biosynthesis metabolic pathway and CAZymes. Water Research, 170, 115309.Qiu, M., & Huang, C. (2015). Removal of dyes from aqueous solution by activated carbon from sewage sludge of the municipal wastewater treatment plant. Desalination and Water Treatment, 53, 3641–3648.Rawal, S., Joshi, B., & Kumar, Y. (2018). Synthesis and characterization of activated carbon from the biomass of Saccharum bengalense for electrochemical supercapacitors. The Journal of Energy Storage, 20, 418–426.Satya Sai, P. M., & Krishnaiah, K. (2005). Development of the pore-size distribution in activated carbon produced from coconut shell char in a fluidized-bed reactor. Industrial and Engineering Chemistry Research, 44, 51–60.Shen, F., Liu, J., Zhang, Z., Dong, Y., & Gu, C. (2018). Density functional study of hydrogen sulfide adsorption mechanism on activated carbon. Fuel Processing Technology, 171, 258–264.Sing, K. S. W., Everett, D. H., Haul, R. A. W., Moscou, L., Pierotti, R. A., Rouquerol, J., & Siemieniewska, T. (1985). Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity. Pure and Applied Chemistry, 57.Sulaiman, N. S., Hashim, R., Mohamad Amini, M. H., Danish, M., & Sulaiman, O. (2018). Optimization of activated carbon preparation from cassava stem using response surface methodology on surface area and yield. Journal of Cleaner Production, 198, 1422–1430.Sun, K., Huang, Q., Chi, Y., & Yan, J. (2018). Effect of ZnCl2-activated biochar on catalytic pyrolysis of mixed waste plastics for producing aromatic-enriched oil. Waste Management, 81, 128–137.Tian, D., Xu, Z., Zhang, D., Chen, W., Cai, J., Deng, H., Sun, Z., & Zhou, Y. (2019). Micro–mesoporous carbon from cotton waste activated by FeCl3/ZnCl2: preparation, optimization, characterization and adsorption of methylene blue and eriochrome black T. Journal of Solid State Chemistry, 269, 580–587.Wang, X., Zhu, N., & Yin, B. (2008). Preparation of sludge-based activated carbon and its application in dye wastewater treatment. Journal of Hazardous Materials, 153, 22–27.Wang, N., Zhang, W., Cao, B., Yang, P., Cui, F., & Wang, D. (2018). Advanced anaerobic digested sludge dewaterability enhancement using sludge based activated carbon (SBAC) in combination with organic polymers. Chemical Engineering Journal, 350, 660–672.Wei Yu, K. S. (2018). Modeling gas adsorption in Marcellus shale using Langmuir and BET isotherms. In Shale gas and tight oil reservoir simulation (pp. 129–154).Ye, Y., Ngo, H. H., Guo, W., Liu, Y., Chang, S. W., Nguyen, D. 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Nitrogen recovery from sludge centrate by membrane contactor: Influence of operating parameters and cleaning conditions

[EN] In urban wastewater treatment, the sludge generated is treated by anaerobic digestion, to be subsequently dehydrated by centrifuges. Currently, the liquid fraction obtained in this dehydration process is recirculated at the head of the treatment plant. However, its high nitrogen and phosphorus content makes it an effluent with high added value. The recovery of these nutrients could be an excellent alternative for the production of fer-tilizers or other industrial applications. In this study, the use of a liquid-liquid phase membrane contactor is presented as a favorable solution for the recovery of ammoniacal nitrogen from sludge centrated. The poly-propylene hollow fiber membrane was evaluated considering its ammonia removal and recovery capacity. For this, different parameters were evaluated: the influence of the type and concentration of the acid solution, the wastewater pH, the flow rates of feeding and the acid stripping solution, and the contact time. Results showed that with a contact time of 65 min, ammonia removal and recovery percentages of the order of 90% were achieved. The flow rates of the stripping and feed solutions together with the acid concentration did not have a significant influence on the removal but on the recovery. Concerning used acid, sulphuric and phosphoric acid solutions achieved better results than nitric acid solution. The most critical parameter was the pH, obtaining the highest removal and recovery of ammonium at the highest pH. Finally, a stable cleaning protocol was obtained, between preventive and moderate cleanings to avoid severe cleanings, keeping the membrane at its maximum capacity.Cifuentes-Cabezas, M.; Lujan Facundo, MJ.; Cuartas Uribe, BE.; Iborra Clar, A.; Mendoza Roca, JA. (2023). Nitrogen recovery from sludge centrate by membrane contactor: Influence of operating parameters and cleaning conditions. Journal of Environmental Management. 341. https://doi.org/10.1016/j.jenvman.2023.11805134

Management of table olive processing wastewater by an osmotic membrane bioreactor process

[EN] The management of fermentation brines from the table olive processing is very complex due to its characteristics: high salinity and high organic matter concentration including phenolic compounds, which behave as slow degradable compounds when a biological process is performed. In this work, the management of these effluents by an osmotic membrane bioreactor has been assessed. This technique combines a biological reactor with forward osmosis membranes. For the study, a laboratory plant consisting of 1 L reactor and a forward osmosis module equipped with a membrane of 42 cm(2) of active surface has been used. Fermentation brine from table olive processing was fed to the system both as draw solution to set out the driving force for the membrane process and as a part of the feed to the reactor, mixing it with municipal wastewater. The experiments were carried out at a constant feed to microorganism ratio of 0.4 g COD.g SS-1.d(-1). Results indicated that the hypersaline effluent was able to produce the needed driving force by the process. Permeate fluxes ranged between 1 and 1.5 L.m(-2).h(-1) after the flux decay of the first operation days. Concerning the biological reaction, it has to be highlighted that phenols were eliminated after 24 days. Until that day, the biological process was jeopardized due to the quick increase of the conductivity in the reactor (ranging between 30 and 35 mS.cm(-1)), which was caused not only by the salinity of the influent but also by the reverse salt flux phenomenon. Soluble microbial products and extracted extracellular polymeric substances also increased in the reactor during the start-up.This study was supported by the Spanish Ministry of Economy and Competitiveness through the project RTC-2015-3582-5-ARLujan Facundo, MJ.; Mendoza Roca, JA.; Soler-Cabezas, JL.; Bes-Piá, M.; Vincent Vela, MC.; Cuartas Uribe, BE.; Pastor-Alcaniz, L. (2020). Management of table olive processing wastewater by an osmotic membrane bioreactor process. Separation and Purification Technology. 248:1-7. https://doi.org/10.1016/j.seppur.2020.117075S1724