495 research outputs found

    Preliminary data set to assess the performance of an outdoor membrane photobioreactor

    Get PDF
    [EN] This data in brief (DIB) article is related to a Research article entitled 'Optimising an outdoor membrane photobioreactor for tertiary sewage treatment' [1]. Data related to the effect of substrate turbidity, the ammonium concentration at which the culture reaches nitrogen-deplete conditions and the microalgae growth rate under outdoor conditions is provided. Microalgae growth rates under different substrate turbidity were obtained to assess the reduction of the culture's light availability. Lab-scale experiments showed growth rates reductions of 22-44%. Respirometric tests were carried to know the limiting ammonium concentration in thismicroalgae-basedwastewater treatment system. Growth rates (m) of green microalgae Scenedesmus and Chlorella obtained under outdoor conditions; i.e. 0.40 d(-1) (R-2 = 0.993) and 0.43 d(-1) (R-2 = 0.995), respectively, can be useful to obtain optimum operating conditions of membrane photobioreactor (MPBR).This research work 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. It also received support from the Spanish Ministry of Education, Culture and Sport via a pre-doctoral FPU fellowship to the first author (FPU14/05082).Gonzalez-Camejo, J.; Jiménez Benítez, AL.; Ruano, MV.; Robles Martínez, Á.; Barat, R.; Ferrer, J. (2019). Preliminary data set to assess the performance of an outdoor membrane photobioreactor. Data in Brief. 27:1-7. https://doi.org/10.1016/j.dib.2019.104599S172

    Anaerobic biodegradation of oleic and palmitic acids : evidence of mass transfer limitations caused by long chain fatty acid accumulation onto the anaerobic sludge

    Get PDF
    Palmitic acid was the main long chain fatty acids (LCFA) that accumulated onto the anaerobic sludge when oleic acid was fed to an EGSB reactor. The conversion between oleic and palmitic acid was linked to the biological activity. When palmitic acid was fed to an EGSB reactor it represented also the main LCFA that accumulated onto the sludge. The way of palmitic acid accumulation was different in the oleic and in the palmitic acid fed reactors.Whenoleic acid was fed, the biomass-associated LCFA (83% as palmitic acid) were mainly adsorbed and entrapped in the sludge that became ‘‘encapsulated’’ by an LCFA layer. However, when palmitic acid was fed, the biomass-associated LCFA (the totality as palmitic acid) was mainly precipitated in white spots like precipitates in between the sludge, which remained ‘‘non-encapsulated.’’ The two sludges were compared in terms of the specific methanogenic activity (SMA) in the presence of acetate, propionate, butyrate, and H2CO2, before and after the mineralization of similar amounts of biomassassociated LCFA (4.6 and 5.2 g COD-LCFA/g of volatile suspended solids (VSS), for the oleic and palmitic acid fed sludge, respectively). The ‘‘non-encapsulated,’’ sludge exhibited a considerable initial methanogenic activity on all the tested substrates, with the single exception of butyrate. However, with the ‘‘encapsulated’’ sludge only methane production from ethanol andH2/CO2 was detected, after a lag phase of about 50 h. After mineralization of the biomass-associated LCFA, both sludges exhibited activities of similar order of magnitude in the presence of the same individual substrates and significantly higher than before. The results evidenced that LCFA accumulation onto the sludge can create a physical barrier and hinder the transfer of substrates and products, inducing a delay on the initial methane production. Whatever the mechanism, metabolic or physical, that is behind this inhibition, it is reversible, being eliminated after the depletion of the biomass-associated LCFA.Fundação para a CiĂȘncia e Tecnologia (FCT) Fundo Social Europeu (FSE

    Efficacy of different antifouling treatments for seawater cooling systems

    Get PDF
    In an industrial seawater cooling system, the effects of three different antifouling treatments, viz. sodium hypochlorite (NaClO), aliphatic amines (Mexel1432) and UV radiation, on the characteristics of the fouling formed were evaluated. For this study a portable pilot plant, as a side-stream monitoring system and seawater cooling system, was employed. The pilot plant simulated a power plant steam condenser, having four titanium tubes under different treatment patterns, where fouling progression could be monitored. The nature of the fouling obtained was chiefly inorganic, showing a clear dependence on the antifouling treatment employed. After 72 days the tubes under treatment showed a reduction in the heat transfer resistance (R) of around 70% for NaClO, 48% for aliphatic amines and 55% for UV, with respect to the untreated tube. The use of a logistic model was very useful for predicting the fouling progression and the maximum asymptotic value of the increment in the heat transfer resistance (DRmax). The apparent thermal conductivity (l) of the fouling layer showed a direct relationship with the percentage of organic matter in the collected fouling. The characteristics and mode of action of the different treatments used led to fouling with diverse physicochemical properties

    Sodium dodecyl sulfate allows the persistence and recovery of biofilms of Pseudomonas fluorescens formed under different hydrodynamic conditions

    Get PDF
    The effect of the anionic surfactant sodium dodecyl sulfate (SDS) on Pseudomonas fluorescens biofilms was investigated using flow cell reactors with stainless steel substrata, under turbulent (Re=5200) and laminar (Re=2000) flow. Steady-state biofilms were exposed to SDS in single doses (0.5, 1, 3 and 7 mM) and biofilm respiratory activity and mass measured at 0, 3, 7 and 12 h after the SDS application. The effect of SDS on biofilm mechanical stability was assessed using a rotating bioreactor. Whilst high concentrations (7 mM) of SDS promoted significant biofilm inactivation, it did not significantly reduce biofouling. Turbulent and laminar flow-generated biofilms had comparable susceptibility to SDS application. Following SDS exposure, biofilms rapidly recovered over the following 12 h, achieving higher respiratory activity values than before treatment. This phenomenon of posttreatment recovery was more pronounced for turbulent flow-generated biofilms, with an increase in SDS concentration. The mechanical stability of the biofilms increased with surfactant application, except for SDS concentrations near the critical micellar concentration, as measured by biofilm removal due to an increase in external shear stress forces. The data suggest that although SDS exerts antimicrobial action against P. fluorescens biofilms, even if only partial and reversible, it had only limited antifouling efficacy, increasing biofilm mechanical stability at low concentrations and allowing significant and rapid recovery of turbulent flow-generated biofilms.Fundação para a CiĂȘncia e a Tecnologia (FCT

    Fed-batch fermentation of olive mill wastewaters for lipase production

    Get PDF
    In the Mediterranean basin countries, huge amounts of olive mill wastewaters (OMW) are produced by the olive oil industry. It constitutes a serious environmental problem, nevertheless its composition turns OMW into a potential growth medium to lipolytic microorganisms. The aim of this work was to study lipase production as well as OMW degradation in fed-batch cultures of Candida cylindracea CBS 7869, Candida rugosa CBS 2275 and Yarrowia lipolytica W29 (ATCC 20460). Besides the improvement of lipase production, the fed-batch approach enhanced the effluent degradation, since it led to good COD and lipids reduction, both higher than 50%. C. rugosa achieved the highest value of lipase productivity (130 U L−1 h−1), in parallel with highest lipids reduction (77%). This study demonstrates thatOMWare becoming a competitive and valuable growth medium in fermentation processes with lipolytic microorganisms. The fed-batch strategy used proved to be an efficient approach to enhance lipase production from OMW and to reduce significantly the final organic load of the medium.The authors acknowledge the financial support provided by 'Fundacao para a Ciencia e Tecnologia' (Project PTDC/AMB/69379/2006; Grant SFRH/BD/27915/2006)

    Wastewater nutrient removal in a mixed microalgae bacteria culture: effect of light and temperature on the microalgae bacteria competition

    Full text link
    [EN] The aim of this study was to evaluate the effect of light intensity and temperature on nutrient removal and biomass productivity in a microalgaeÂżbacteria culture and their effects on the microalgaeÂżbacteria competition. Three experiments were carried out at constant temperature and various light intensities: 40, 85 and 125¿”EÂżmÂż2ÂżsÂż1. Other two experiments were carried out at variable temperatures: 23¿±¿2°C and 28¿±¿2°C at light intensity of 85 and 125¿”EÂżmÂż2ÂżsÂż1, respectively. The photobioreactor was fed by the effluent from an anaerobic membrane bioreactor. High nitrogen and phosphorus removal efficiencies (about 99%) were achieved under the following operating conditions: 85Âż125¿”EÂżmÂż2ÂżsÂż1 and 22¿±¿1°C. In the microalgaeÂżbacteria culture studied, increasing light intensity favoured microalgae growth and limited the nitrification process. However, a non-graduated temperature increase (up to 32°C) under the light intensities studied caused the proliferation of nitrifying bacteria and the nitrite and nitrate accumulation. Hence, light intensity and temperature are key parameters in the control of the microalgaeÂżbacteria competition. Biomass productivity significantly increased with light intensity, reaching 50.5¿±¿9.6, 80.3¿±¿6.5 and 94.3¿±¿7.9ÂżmgVSSÂżLÂż1ÂżdÂż1 for a light intensity of 40, 85 and 125¿”EÂżmÂż2ÂżsÂż1, respectivelyThis research work was possible because of Projects CTM2011-28595-C02-01 and CTM2011-28595-C02-02 [funded by the Spanish Ministry of Economy and Competitiveness jointly with the European Regional Development Fund and the Generalitat Valenciana GVA-ACOMP2013/203]. This research was also supported by the Spanish Ministry of Education, Culture and Sport via a pre doctoral FPU fellowship to the first author [FPU14/05082].Gonzalez-Camejo, J.; Barat, R.; PachĂ©s Giner, MAV.; Murgui Mezquita, M.; Seco Torrecillas, A.; Ferrer, J. (2018). Wastewater nutrient removal in a mixed microalgae bacteria culture: effect of light and temperature on the microalgae bacteria competition. Environmental Technology. 39(4):503-515. https://doi.org/10.1080/09593330.2017.1305001S503515394GimĂ©nez, J. B., Robles, A., Carretero, L., DurĂĄn, 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.2011.07.014Huang, Z., Ong, S. L., & Ng, H. Y. (2011). Submerged anaerobic membrane bioreactor for low-strength wastewater treatment: Effect of HRT and SRT on treatment performance and membrane fouling. Water Research, 45(2), 705-713. doi:10.1016/j.watres.2010.08.035Ruiz-Martinez, A., Martin Garcia, N., Romero, I., Seco, A., & Ferrer, J. (2012). Microalgae cultivation in wastewater: Nutrient removal from anaerobic membrane bioreactor effluent. Bioresource Technology, 126, 247-253. doi:10.1016/j.biortech.2012.09.022Chisti, Y. (2007). Biodiesel from microalgae. Biotechnology Advances, 25(3), 294-306. doi:10.1016/j.biotechadv.2007.02.001Rawat, I., Bhola, V., Kumar, R. R., & Bux, F. (2013). Improving the feasibility of producing biofuels from microalgae using wastewater. Environmental Technology, 34(13-14), 1765-1775. doi:10.1080/09593330.2013.826287Collet, P., HĂ©lias, A., Lardon, L., Ras, M., Goy, R.-A., & Steyer, J.-P. (2011). Life-cycle assessment of microalgae culture coupled to biogas production. Bioresource Technology, 102(1), 207-214. doi:10.1016/j.biortech.2010.06.154Milledge, J. J. (2010). Commercial application of microalgae other than as biofuels: a brief review. Reviews in Environmental Science and Bio/Technology, 10(1), 31-41. doi:10.1007/s11157-010-9214-7Posadas, E., GarcĂ­a-Encina, P.-A., Soltau, A., DomĂ­nguez, A., DĂ­az, I., & Muñoz, R. (2013). Carbon and nutrient removal from centrates and domestic wastewater using algal–bacterial biofilm bioreactors. Bioresource Technology, 139, 50-58. doi:10.1016/j.biortech.2013.04.008Podevin, M., De Francisci, D., Holdt, S. L., & Angelidaki, I. (2014). Effect of nitrogen source and acclimatization on specific growth rates of microalgae determined by a high-throughput in vivo microplate autofluorescence method. Journal of Applied Phycology, 27(4), 1415-1423. doi:10.1007/s10811-014-0468-2Meseck, S. L., Smith, B. C., Wikfors, G. H., Alix, J. H., & Kapareiko, D. (2006). Nutrient interactions between phytoplankton and bacterioplankton under different carbon dioxide regimes. Journal of Applied Phycology, 19(3), 229-237. doi:10.1007/s10811-006-9128-5Risgaard-Petersen, N., Nicolaisen, M. H., Revsbech, N. P., & Lomstein, B. A. (2004). Competition between Ammonia-Oxidizing Bacteria and Benthic Microalgae. Applied and Environmental Microbiology, 70(9), 5528-5537. doi:10.1128/aem.70.9.5528-5537.2004Tiquia-Arashiro, S. M., & Mormile, M. (2013). Sustainable technologies: bioenergy and biofuel from biowaste and biomass. Environmental Technology, 34(13-14), 1637-1638. doi:10.1080/09593330.2013.834162Jordan, B. R. (1996). The Effects of Ultraviolet-B Radiation on Plants: A Molecular Perspective. Advances in Botanical Research, 97-162. doi:10.1016/s0065-2296(08)60057-9Znad, H., Naderi, G., Ang, H. M., & Tade, M. O. (2012). CO2 Biomitigation and Biofuel Production Using Microalgae: Photobioreactors Developments and Future Directions. Advances in Chemical Engineering. doi:10.5772/32568MartĂ­nez, M. (2000). Nitrogen and phosphorus removal from urban wastewater by the microalga Scenedesmus obliquus. Bioresource Technology, 73(3), 263-272. doi:10.1016/s0960-8524(99)00121-2Xin, L., Hong-ying, H., & Yu-ping, Z. (2011). Growth and lipid accumulation properties of a freshwater microalga Scenedesmus sp. under different cultivation temperature. Bioresource Technology, 102(3), 3098-3102. doi:10.1016/j.biortech.2010.10.055Robles, Á., DurĂĄn, 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:10.1080/09593330.2015.1012180Reynolds, C. S. (2006). The Ecology of Phytoplankton. doi:10.1017/cbo9780511542145KĂŒster, E., Dorusch, F., & Altenburger, R. (2005). EFFECTS OF HYDROGEN SULFIDE TO VIBRIO FISCHERI, SCENEDESMUS VACUOLATUS, AND DAPHNIA MAGNA. Environmental Toxicology and Chemistry, 24(10), 2621. doi:10.1897/04-546r.1Park, J., Jin, H.-F., Lim, B.-R., Park, K.-Y., & Lee, K. (2010). Ammonia removal from anaerobic digestion effluent of livestock waste using green alga Scenedesmus sp. Bioresource Technology, 101(22), 8649-8657. doi:10.1016/j.biortech.2010.06.142McGinn, P. J., Dickinson, K. E., Park, K. C., Whitney, C. G., MacQuarrie, S. P., Black, F. J., 
 O’Leary, S. J. B. (2012). Assessment of the bioenergy and bioremediation potentials of the microalga Scenedesmus sp. AMDD cultivated in municipal wastewater effluent in batch and continuous mode. Algal Research, 1(2), 155-165. doi:10.1016/j.algal.2012.05.001Mara, D. D., & Feachem, R. G. A. (2003). Unitary environmental classification of water- and excreta-related communicable diseases. Handbook of Water and Wastewater Microbiology, 185-192. doi:10.1016/b978-012470100-7/50012-1Jeffrey, S. W., & Humphrey, G. F. (1975). New spectrophotometric equations for determining chlorophylls a, b, c1 and c2 in higher plants, algae and natural phytoplankton. Biochemie und Physiologie der Pflanzen, 167(2), 191-194. doi:10.1016/s0015-3796(17)30778-3LalibertĂ©, G., Lessard, P., de la NoĂŒe, J., & Sylvestre, S. (1997). Effect of phosphorus addition on nutrient removal from wastewater with the cyanobacterium Phormidium bohneri. Bioresource Technology, 59(2-3), 227-233. doi:10.1016/s0960-8524(96)00144-7PachĂ©s, M., Romero, I., Hermosilla, Z., & Martinez-Guijarro, R. (2012). PHYMED: An ecological classification system for the Water Framework Directive based on phytoplankton community composition. Ecological Indicators, 19, 15-23. doi:10.1016/j.ecolind.2011.07.003Xin, L., Hong-ying, H., Ke, G., & Jia, Y. (2010). Growth and nutrient removal properties of a freshwater microalga Scenedesmus sp. LX1 under different kinds of nitrogen sources. Ecological Engineering, 36(4), 379-381. doi:10.1016/j.ecoleng.2009.11.003Wang, L., Min, M., Li, Y., Chen, P., Chen, Y., Liu, Y., 
 Ruan, R. (2009). Cultivation of Green Algae Chlorella sp. in Different Wastewaters from Municipal Wastewater Treatment Plant. Applied Biochemistry and Biotechnology, 162(4), 1174-1186. doi:10.1007/s12010-009-8866-7Pancha, I., Chokshi, K., George, B., Ghosh, T., Paliwal, C., Maurya, R., & Mishra, S. (2014). Nitrogen stress triggered biochemical and morphological changes in the microalgae Scenedesmus sp. CCNM 1077. Bioresource Technology, 156, 146-154. doi:10.1016/j.biortech.2014.01.025Sarat Chandra, T., Deepak, R. S., Maneesh Kumar, M., Mukherji, S., Chauhan, V. S., Sarada, R., & Mudliar, S. N. (2016). Evaluation of indigenous fresh water microalga Scenedesmus obtusus for feed and fuel applications: Effect of carbon dioxide, light and nutrient sources on growth and biochemical characteristics. Bioresource Technology, 207, 430-439. doi:10.1016/j.biortech.2016.01.044Krustok, I., Odlare, M., Truu, J., & Nehrenheim, E. (2016). Inhibition of nitrification in municipal wastewater-treating photobioreactors: Effect on algal growth and nutrient uptake. Bioresource Technology, 202, 238-243. doi:10.1016/j.biortech.2015.12.020Chen, X., Goh, Q. Y., Tan, W., Hossain, I., Chen, W. N., & Lau, R. (2011). Lumostatic strategy for microalgae cultivation utilizing image analysis and chlorophyll a content as design parameters. Bioresource Technology, 102(10), 6005-6012. doi:10.1016/j.biortech.2011.02.061Powell, N., Shilton, A., Chisti, Y., & Pratt, S. (2009). Towards a luxury uptake process via microalgae – Defining the polyphosphate dynamics. Water Research, 43(17), 4207-4213. doi:10.1016/j.watres.2009.06.011Cabello, J., Toledo-Cervantes, A., SĂĄnchez, L., Revah, S., & Morales, M. (2015). Effect of the temperature, pH and irradiance on the photosynthetic activity by Scenedesmus obtusiusculus under nitrogen replete and deplete conditions. Bioresource Technology, 181, 128-135. doi:10.1016/j.biortech.2015.01.034Zhu, W., Wan, L., & Zhao, L. (2010). Effect of nutrient level on phytoplankton community structure in different water bodies. Journal of Environmental Sciences, 22(1), 32-39. doi:10.1016/s1001-0742(09)60071-1Daims, H., BrĂŒhl, A., Amann, R., Schleifer, K.-H., & Wagner, M. (1999). 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)80053-8Daims, H., Nielsen, J. L., Nielsen, P. H., Schleifer, K.-H., & Wagner, M. (2001). In Situ Characterization of Nitrospira-Like Nitrite-Oxidizing Bacteria Active in Wastewater Treatment Plants. Applied and Environmental Microbiology, 67(11), 5273-5284. doi:10.1128/aem.67.11.5273-5284.2001analysis of nitrifying bacteria in sewage treatment plants. (1996). Water Science and Technology, 34(1-2). doi:10.1016/0273-1223(96)00514-

    Long-term acclimation of anaerobic sludges for high-rate methanogenesis from LCFA

    Get PDF
    Inhibition of methanogens by long chain fatty acids (LCFA) and the low numbers of LCFA-degrading bacteria are limitations to exploit biogas production from fat-rich wastewaters. Generally reactors fail due to excessive LCFA accumulation onto the sludge. Here, long-term acclimation and bioaugmentation with a LCFA-degrading coculture were hypothesized as strategies to enhance methanogenic conversion of these compounds. Anaerobic sludges previously exposed to LCFA for more than 100 days converted a specific biomass-associated substrate of (3.2 ± 0.1) kg·kg−1 with very short lag phases (<1 day), whereas non-acclimated sludges showed lag phases of 11–15 days for metabolizing (1.6–1.8) kg·kg−1. Addition of a coculture of Syntrophomonas zehnderi and Methanobacterium formicicum to sludges previously loaded with LCFA and containing different amounts of biomass-associated substrate (from (0.5–3.2) kg·kg−1) did not improve methane production neither lag phases were shortened, indicating that the endogenous microbiota are not a limiting factor. Clearly, we show that long-term sludge acclimation to LCFA is essential for high rate methanogenesis from LCFA.The authors acknowledge the financial support by the European Regional Development Fund - ERDF, through the Operational Program Thematic Factors of Competitiveness - COMPETE, and by Portuguese funds, through the Portuguese Foundation for Science and Technology (FCT), in the frame of the project FCOMP-01-0124-FEDER-014784. FCT Strategic Project PEst-OE/EQB/LA0023/2013 is also acknowledged. A.J. Cavaleiro thanks FCT for the post-doctoral fellowship ref. SFRH/BPD/75247/2010. A.J.M. Stams has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement n. [323009]

    Long term outdoor operation of a tubular airlift pilot photobioreactor and a high rate algal pond as tertiary treatment of urban wastewater.

    Get PDF
    530 L high rate alga pond (HRAP) and 380 L airlift tubular photobioreactor (TPBR) were operated and compared in a urban wastewater treatment plant (WWTP), with the main purpose of removing nitrogen and phosphorous from the effluent of the WWTP while generating a valuable biomass. The photosynthetic activity in TPBR was during entire experiment higher than HRAP. The maximum areal productivity reached was 8.26 ± 1.43 and 21.76 ± 0.3 g SS m−2 d−1 for HRAP and TPBR respectively. Total nitrogen (TN) removal averaged 89.68 ± 3.12 and 65.12 ± 2.87% for TPBR and HRAP respectively, while for total phosphorus (TP) TPBR and HRAP averaged 86.71 ± 0.61 and 58.78 ± 1.17% respectively. The lipid content showed no significant differences (p < 0.05) between HRAP and TPBR averaging 20.80 ± 0.22 wt%. The main operating disadvantage of TPBR versus HRAP was the sever biofouling which forced to stop the experiment. Under the same conditions of operation TPBR was more limited at low temperatures than HRAP, and HRAP was more light limited than TPBR
    • 

    corecore