Search results for " reactor"

Effect of long residence time and high temperature over anaerobic biodegradation of Scenedesmus microalgae grown in wastewater

2018

[EN] Anaerobic digestion of indigenous Scenedesmus spp. microalgae was studied in continuous lab-scale anaerobic reactors at different temperatures (35 degrees C and 55 degrees C), and sludge retention time - SRT (50 and 70 days). Mesophilic digestion was performed in a continuous stirred-tank reactor (CSTR) and in an anaerobic membrane bioreactor (AnMBR). Mesophilic CSTR operated at 50 days SRT only achieved 11.9% of anaerobic biodegradability whereas in the AnMBR at 70 days SRT and 50 days HRT reached 39.5%, which is even higher than the biodegradability achieved in the thermophilic CSTR at 50 days SRT (30.4%). Microbial analysis revealed a high abundance of cellulose-degraders in both re…

Microbial community analysis, influence of reactor hybridation and effect of the proportion of glycol ethers/ethanol mixtures in EGSB reactors

2018

Antecedentes La emisión de compuestos orgánicos volátiles (COVs) puede causar diferentes problemas en la salud pública y en el medio ambiente, actuando como contaminantes primarios y permitiendo la formación de contaminantes secundarios como el ozono troposférico. Debido a estos problemas, la emisión de COVs está limitada en muchos países tales como EEUU o los pertenecientes a la Unión Europea, en este caso regulado por la directiva 2010/75/EU. Debido al uso de disolventes en su proceso productivo, la industria flexográfica es uno de los sectores que más contribuye a la emisión de este tipo de compuestos, y las técnicas biológicas han sido consideradas como una de las mejores disponibles pa…

Analysis of the OSU-MASLWR-003A natural circulation test by using the trace code

2012

Effect of biomass features on oxygen transfer in conventional activated sludge and membrane bioreactor systems

2019

Abstract The aim of the present study was to compare the oxygen transfer efficiency in a conventional activated sludge and a membrane bioreactor system. The oxygen transfer was evaluated by means of the oxygen transfer coefficient and α-factor calculation, under different total suspended solids concentration, extracellular polymeric substances, sludge apparent viscosity and size of the flocs. The oxygen transfer coefficient and α-factor showed an exponential decreasing trend with total suspended solid, with a stronger oxygen transfer coefficient dependence in the conventional activated sludge compared to the membrane bioreactor. It was noted that the oxygen transfer coefficient in the conve…

Comparison of EPR response of alanine and Gd2O3-alanine dosimeters exposed to TRIGA Mainz reactor.

2015

In this work we report some preliminary results regarding the analysis of electron paramagnetic resonance (EPR) response of alanine pellets and alanine pellets added with gadolinium used for dosimetry at the TRIGA research reactor in Mainz, Germany. Two set-ups were evaluated: irradiation inside PMMA phantom and irradiation inside boric acid phantom. We observed that the presence of Gd2O3 inside alanine pellets increases the EPR signal by a factor of 3.45 and 1.24 in case of PMMA and boric acid phantoms, respectively. We can conclude that in the case of neutron beam with a predominant thermal neutron component the addition of gadolinium oxide can significantly improve neutron sensitivity of…

Effect of Temperature on N2O and NO Emission in a Partial Nitrification SBR Treating Reject Wastewater

2017

Temperature is a very important parameter during nitritation, having a direct effect on ammonia oxidation rate (AOR) and enzymatic activities which relate to both N2O and NO emission. This study aims at investigating the effect of temperature on AOR, N2O and NO production in an enriched ammonia oxidizing bacteria (AOB) sequencing batch reactor (SBR) performing partial nitrification (PN) of synthetic reject wastewater. To achieve that, a SBR was subject to several shifts in temperature (in the range of 30 to 15 °C, 5 °C for each decrease). Cycle studies, which contain two aeration phases, were conducted under each temperature. The results showed that AOR specific exponentially correlates wit…

Anaerobic moving bed biofilm reactor followed by aerobic granular sludge for brewery wastewater treatment

2018

Small and medium breweries discharging to municipal sewers without treatment generate significant loads with typical concentrations reported by Valta et al. (2014) as 2-6 g COD L-1, 25-80 mg TN L-1, 10-50 mg TP L-1, with pH between 4.5 and 12. Treatment of the high-strength wastewater requires specialized low footprint processes, such as aerobic granular sludge (AGS), capable of high-rate degradation, as well as simultaneous nitrogen and phosphorous removal (Wang et al., 2007). The objective of this study was to evaluate the start-up period of AGS receiving brewery wastewater after initial anaerobic pre-treatment.

Dimensionless Analysis Of Slurry Photocatalytic Reactors Using Two-Flux And Six-Flux Radiation Absorption-Scattering Models

2007

Photocatalytic oxidation (PCO) over titanium dioxide (TiO2) is a "green" sustainable process for the treatment and purification of water and wastewater. However,the application of PCO for wastewater treatment on an industrial scale is currently hindered by a lack of simple mathematical models that can be readily applied to reactor design. Current models are either too simplistic or too rigorous to be useful in photocatalytic reactor design, scale-up, and optimization. In this paper a simple mathematical model is presented for slurry, annular, photocatalytic reactors that still retains the essential elements of a rigorous approach while providing simple solutions. The model extends the appli…

Photocatalytic degradation of dyes by using a membrane reactor

2004

Abstract Dyes are organic compounds used in textile, food and drug industries, and their abatement represents one of the main problems in the treatment processes because generally they are very stable toxic compounds. In this work, two commercial azo-dyes, i.e. Congo Red (C32H22N6Na2O6S2) and Patent Blue (C27H31N2NaO6S2), in aqueous solution were degraded in a photocatalytic membrane reactor by using TiO2 Degussa P25 as the catalyst. Different system configurations and irradiating sources were studied, and the influence of some operational parameters such as the pressure in the membrane cell and the initial concentration of the substrates was determined. A comparison between suspended and e…

The n_TOF facility: Neutron beams for challenging future measurements at CERN

2016

The CERN n TOF neutron beam facility is characterized by a very high instantaneous neutron flux, excellent TOF resolution at the 185 m long flight path (EAR-1), low intrinsic background and coverage of a wide range of neutron energies, from thermal to a few GeV. These characteristics provide a unique possibility to perform high-accuracy measurements of neutron-induced reaction cross-sections and angular distributions of interest for fundamental and applied Nuclear Physics. Since 2001, the n TOF Collaboration has collected a wealth of high quality nuclear data relevant for nuclear astrophysics, nuclear reactor technology, nuclear medicine, etc. The overall efficiency of the experimental prog…