21 research outputs found
Evaluation of two different granular sludge reactor configurations for the treatment of freshwater aquaculture streams
Two aerobic distinct granular sludge reactors were operated to treat freshwater aquaculture streams at laboratory-scale: An Expanded Granular Sludge Bed(EGSB)reactor operated in continuous mode and an Aerobic Granular Sludge -Sequencing Batch Reactor(AGS-SBR) operated as a sequencing batch reactor. Both units were fed with low ammonium concentrations (2.5 mg N/L). Granular biomass accumulated in both reactors. With the imposed operational conditions, nitrogen removal was of 10 -20 % and 80 % for the EGSB and AGS-SBR, respectively.info:eu-repo/semantics/publishedVersio
Short and long term orange dye effects over AOB and anammox activities
"This is the pre-peer reviewed version of the following article: Val del RĂo, A., Stachurski, A., MĂ©ndez, R., Campos, J. L., Surmacz-GĂłrska, J., & Mosquera-Corral, A. (2017). Short- and long-term orange dye effects on ammonium oxidizing and anammox bacteria activities. Water Science and Technology, 76(1), 79-86, which has been published in final form at [http://dx.doi.org/10.2166/wst.2017.186. This article may be used for non-commercial purposes in accordance with IWA Publishing."In this research work the effects of orange azo dye over ammonia oxidizing bacteria (AOB) and anammox bacteria activities were tested. Adsorption onto the biomass was detected with both types of biomass however no biological decolourization occurred. Performed batch tests indicated that concentrations lower than 650 mgorange/L stimulated AOB activity while anammox bacteria activity was inhibited at concentrations higher than 25 mgorange/L. Long-term performance of both processes was tested in the presence of 50 mgorange/L. In the case of the partial nitritation process both the biomass concentration and the specific AOB activity increased after 50 days of orange azo dye addition. Regarding the anammox process, specific activity decreased down to 58% after 12 days of operation; however, initial values were restored 54 days after stopping the dye additionThis work was funded by the European Union through the Cost Action (ES-10755) and by the Spanish Government through FISHPOL (CTQ2014-55021-R) and GRANDSEA (CTM2014-55397-JIN) projects co-funded by FEDER. The authors from the USC belong to CRETUS (AGRUP2015/02) and the Galician Competitive Research Group (GRC 2013-032), programs co-funded by FEDERNO
Assessment of an aerobic granular sludge system in the presence of pharmaceutically active compounds by quantitative image analysis and chemometric techniques
In this study, a sequencing batch reactor (SBR) with aerobic granular sludge (AGS) was operated with synthetic wastewater containing environmental relevant concentrations of 17-estradiol (E2), 17-ethinylestradiol (EE2) and sulfamethoxazole (SMX). Despite the presence of the studied PhAC, the granular fraction clearly predominated (TSSgran/TSS ranging from 0.82 to 0.98) throughout the monitoring period, presenting aggregates with high organic fraction (VSS/TSS above 0.83) and good settling characteristics (SVI5 ranging from 15 to 39 mL/gTSS). A principal component analysis (PCA) with quantitative image analysis (QIA) based data allowed to distinguish the different operational periods, namely with mature granules (CONT), and the E2, EE2, and SMX feeding periods. It further revealed a positive relationship between the biomass density, sludge settling ability, overall and granular biomass contents, granulation properties, granular biomass fraction and large granules fraction and size. Moreover, a discriminant analysis (DA) allowed to successfully discriminate not only the different operational periods, mainly by using the floccular apparent density, granular stratification and contents data, but also the PhAC presence in samples. The filamentous bacteria contents, sludge settling properties, settling properties stability and granular stratification, structure and contents parameters were found to be crucial for that purpose.The authors thank the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and the project AGeNT - PTDC/BTA-BTA/31264/2017 (POCI-01-0145-FEDER-031264). We would also like to thank the scientific collaboration under the FCT project UIDB/50016/2020. The authors wish to thank the company Ăguas do Tejo AtlĂąntico, S.A. for supplying the granules. Cristiano Leal is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. A. Val del Rio is supported by Xunta de Galicia (ED418B 2017/075) and program Iacobus (2018/2019). Daniela P. Mesquita and Cristina Quintelas thanks FCT for funding through program DL 57/2016 â Norma transitĂłria. Cristiano Leal also thank to RenĂȘ Benevides for all the support during the experimental activities.info:eu-repo/semantics/publishedVersio
Crecimiento del biofouling en intercambiadores de calor-condensadores refrigerados con agua de mar
[ES] El objetivo de este experimento es el estudio del crecimiento del biofouling en intercambiadores de calor. Para ello se ha diseñado y construido una planta piloto en la cual cada uno de los tubos funciona como sistema independiente. En cada uno de los tubos se controlan parĂĄmetros como presiĂłn, temperatura y caudal, que definen indirectamente la capa de biofouling depositada en el interior del tubo. El seguimiento de estos parĂĄmetros permitirĂĄ establecer los valores de la resistencia a la transmisiĂłn de calor, resistencia friccional y velocidad del fluido.EguĂa LĂłpez, E.; Vidart, TF.; Bezanilla, JA.; Amieva Del Val, JJ.; Otero GonzĂĄlez, FM.; RĂo Calonge, B.; GirĂłn Portilla, MA. (1996). Crecimiento del biofouling en intercambiadores de calor-condensadores refrigerados con agua de mar. IngenierĂa del Agua. 3(4):45-56. https://doi.org/10.4995/ia.1996.2708SWORD455634Characklis, W. G. y Marshall, K. C. (1990). Biofilms, Wiley Series in Ecological and Applied Microbiology.Chenoweth, J. M. (1990) Final Report of the HTRI/TEMA Joint Committee to Review the Fouling Section of the TEMA Standards, Heat Transfer Engineering. 1 1, N°1, 73-107.Chow, W. (1985). Condenser Biofouling Control: The State of Art, Electrical Research Power Institute. 1-11.Flemming, H. C. (1990) Biofouling in Water Treatment, Proceedings of the International Workshops on Industrial Biofouling and Biocorrosion, Stuttgart, 47-80.Knox-Holmes, B. (1993) Biofouling Control with Low Levels of Copper and Chlorine, Biofouling, 7, 157-166.LeBleu, J. B. (1990) Protective Coatings for Cooling Water Systems in Southern Coastal Power Plants, Journal of Protective Coatings & Linings, 20-25.Lewis, J. R. y Mercer, A. D. (1984) Corrosion and Marine Growth on Offshore Structure, Ellis Horwood Limeted.Nosetani, T.; Hotta, Y.; Sato, S.; Onda K.; Nakamura, T. y Kato, Y. (1989). In-Situ Evaluation of Enhanced Heat Transfer Tubes for Surface Condenser (SC Tubes), National Heat Transfer Conference Philadelphia, 31, N° 1, 54-64.Sengupta, S.; Lira, R.; Poteat, L; Mussaili, Y. & Chow, W. (1987) Experimental Test Facility For Evaluating Marine Biofouling in Condensers: Test with Targeted Chlorination, American Society of Mechanical Engineers, Heat Transfer Division, 86, 15-22.Somerscales, E. F. C. y Kassemit, M. (1987) Fouling Due to Corrosion Products Formed on a Heat Transfers Surface, Journal of Heat Transfer, 109, 267-271.Tatnall, R. E. (1990) Case Histories: Biocorrosion, Proceedings of the International Workshops on Industrial Biofouling and Biocorrosion, Stuttgart, 165-185.Tijhuis, L. (1989) The Biofilm Airlift Suspension Reactor, Department of Biochemical Engineering, Delft University of Technology, The Netherlands
La Cruz Roja Española, la repatriación de los soldados de las guerras coloniales y el desarrollo de la ciencia médica en España, 1896-1950
Inactivation efficiency of Bacillus endospores via modified flow-through PUV treatment with comparison to conventional LPUV treatment
Water is a fragile resource, consequently there is a pressing need to develop sustainable environmental-friendly disinfection technologies. This constitutes the first study to compare efficacy of continuous low-pressure UV (LPUV) to that of pulsed UV light (PUV) for UV disinfection performance in flow-through water systems. Bacillus endospores were used as these are frequently deployed as biodosimeters for drinking water UV reactor validation protocols. Results showed a PUV system output of 2,052 mJ/cm(2) (energy below 300 nm) was required for a 2 log inactivation of B.pumilus endospores, whereas a lower LPUV system output of 12 mJ/cm(2) produced a similar level of disinfection. Measurements of dose incident to the samples (which were 10.75 cm from the PUV light source) showed supplementation of cultivation media with manganese sulphate monohydrate (MnSO4 center dot H2O) employed to enhance the rate of endospore formation for propagation was shown to increase the UV resistance of different Bacillus spp. to both irradiation approaches (PThe authors would like to acknowledge the Department of Agriculture, Food and the Marine (Ref: 13-F-507) for funding this research. Dr. Val del Rio was supported by the Xunta de Galicia postdoctoral fellowship, grant no. ED418B 2017/075.peer-reviewed2020-11-2
Inactivation efficiency of Bacillus endospores via modified flow-through PUV treatment with comparison to conventional LPUV treatment
Water is a fragile resource, consequently there is a pressing need to develop sustainable environmental-friendly disinfection technologies. This constitutes the first study to compare efficacy of continuous low-pressure UV (LPUV) to that of pulsed UV light (PUV) for UV disinfection performance in flow-through water systems. Bacillus endospores were used as these are frequently deployed as biodosimeters for drinking water UV reactor validation protocols. Results showed a PUV system output of 2,052 mJ/cm(2) (energy below 300 nm) was required for a 2 log inactivation of B.pumilus endospores, whereas a lower LPUV system output of 12 mJ/cm(2) produced a similar level of disinfection. Measurements of dose incident to the samples (which were 10.75 cm from the PUV light source) showed supplementation of cultivation media with manganese sulphate monohydrate (MnSO4 center dot H2O) employed to enhance the rate of endospore formation for propagation was shown to increase the UV resistance of different Bacillus spp. to both irradiation approaches (PThe authors would like to acknowledge the Department of Agriculture, Food and the Marine (Ref: 13-F-507) for funding this research. Dr. Val del Rio was supported by the Xunta de Galicia postdoctoral fellowship, grant no. ED418B 2017/075.2020-11-2
Chapter 17: Nitrogen removal by anammox-based processes from different anaerobically digested effluents
info:eu-repo/semantics/publishedVersio
Greenhouse Gases Emissions from Wastewater Treatment Plants: Minimization, Treatment, and Prevention
The operation of wastewater treatment plants results in direct emissions, from the biological processes, of greenhouse gases (GHG) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), as well as indirect emissions resulting from energy generation. In this study, three possible ways to reduce these emissions are discussed and analyzed: (1) minimization through the change of operational conditions, (2) treatment of the gaseous streams, and (3) prevention by applying new configurations and processes to remove both organic matter and pollutants. In current WWTPs, to modify the operational conditions of existing units reveals itself as possibly the most economical way to decrease N2O and CO2 emissions without deterioration of effluent quality. Nowadays the treatment of the gaseous streams containing the GHG seems to be a not suitable option due to the high capital costs of systems involved to capture and clean them. The change of WWTP configuration by using microalgae or partial nitritation-Anammox processes to remove ammonia from wastewater, instead of conventional nitrification-denitrification processes, can significantly reduce the GHG emissions and the energy consumed. However, the area required in the case of microalgae systems and the current lack of information about stability of partial nitritation-Anammox processes operating in the main stream of the WWTP are factors to be considered