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Tabernas Almeria, Spain

Joss A.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Baenninger C.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Foa P.,Polytechnic of Milan | Koepke S.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | And 7 more authors.
Water Research | Year: 2011

Over 1.5 years continuous piloting of a municipal wastewater plant upgraded with a double membrane system (ca. 0.6 m 3 d -1 of product water produced) have demonstrated the feasibility of achieving high water quality with a water yield of 90% by combining a membrane bioreactor (MBR) with a submerged ultrafiltration membrane followed by a reverse osmosis membrane (RO). The novelty of the proposed treatment scheme consists of the appropriate conditioning of MBR effluent prior to the RO and in recycling the RO concentrates back to the biological unit. All the 15 pharmaceuticals measured in the influent municipal sewage were retained below 100 ng L -1, a proposed quality parameter, and mostly below detection limits of 10 ng L -1. The mass balance of the micropollutants shows that these are either degraded or discharged with the excess concentrate, while only minor quantities were found in the excess sludge. The micropollutant load in the concentrate can be significantly reduced by ozonation. A low treated water salinity (<10 mM inorganic salts; 280 ± 70 μS cm -1) also confirms that the resulting product has a high water quality. Solids precipitation and inorganic scaling are effectively mitigated by lowering the pH in the RO feed water with CO 2 conditioning, while the concentrate from the RO is recycled to the biological unit where CO 2 is stripped by aeration. This causes precipitation to occur in the bioreactor bulk, where it is much less of a process issue. SiO 2 is the sole exception. Equilibrium modeling of precipitation reactions confirms the effectiveness of this scaling-mitigation approach for CaCO 3 precipitation, calcium phosphate and sulfate minerals. © 2011 Elsevier Ltd. Source

Turki A.,Tunis el Manar University | Turki A.,CNRS Research on Catalysis and Environment in Lyon | Ibanez P.F.,Plataforma Solar de Almeria | Ghorbel A.,Tunis el Manar University | And 3 more authors.
Materials Research Society Symposium Proceedings | Year: 2012

1 D TiO2 nanomaterials (nanotubes, nanowires) were synthesized through hydrothermal treatment of TiO2 powder (P25) in concentrated alkaline solutions (NaOH for nanotubes, KOH for nanowires) followed by calcination at varying temperatures between 400°C and 700°C Samples were characterized by HRTEM, XRD, Raman spectroscopy, and N2 adsorption-desorption isotherms. High surface area nanotubular TiO2 materials can maintain their 1D morphology up to a temperature of calcination of 400°C while changing their phase from hydrogenotitanate to anatase. The use of KOH leads to a retarded formation of anatase. Photocatalytic results showed that TiO2 anatase nanotubes calcined at 400°C can degrade formic acid with a rate constant four times higher than for P25. A direct correlation between surface area and photocatalytic activity explains the much higher activity of TiO2 anatase nanotubes. On the opposite, for the degradation of phenol, P25 remains more active. In the disinfection of water, contrary to P25, the high surface area of TiO2 nanotubes allows the simultaneous degradation of formic acid and the inactivation of pathogen fungus showing the interest of such materials for the treatment of wastewater. © 2012 Materials Research Society. Source

Torrico B.C.,Federal University of Ceara | Roca L.,University of Almeria | Normey-Rico J.E.,Federal University of Santa Catarina | Guzman J.L.,University of Almeria | Yebra L.,Plataforma Solar de Almeria
2009 European Control Conference, ECC 2009 | Year: 2015

This paper presents the application of nonlinear predictive control to the distributed collector field of a solar desalination plant. The main purpose of the controller is to manipulate the water flow rate to maintain an outlet-inlet temperature gradient in the collectors in spite of disturbances and water flow rate constraints. The controller uses a deadtime compensation structure to account for the time delay and a nonlinear MPC to compute the control law. Simulation results using real disturbances data are used to illustrate the controller performance. © 2009 EUCA. Source

Papoutsakis S.,Ecole Polytechnique Federale de Lausanne | Afshari Z.,Ecole Polytechnique Federale de Lausanne | Malato S.,Plataforma Solar de Almeria | Pulgarin C.,Ecole Polytechnique Federale de Lausanne
Journal of Environmental Chemical Engineering | Year: 2015

The use of ultrasound and photo-Fenton advanced oxidation processes has been investigated for the treatment of aquatic media contaminated with the iodinated contrast agent Iohexol. Iohexol is primarily introduced in the water network from hospitals discharging the urine of patients submitted to medical imaging. Treatment options have been considered for eliminating either highly concentrated solutions (up to 6 g L-1) at the hospital source (in urine) or highly diluted (in the mg L-1 range) within municipal wastewater. Although the efficiency of ultrasound was shown to be low, complete Iohexol removal was achieved by application of photo-Fenton in diluted urine, Advantages and disadvantages of each option are discussed and the biodegradability of solutions subjected to the treatment has been evaluated. © 2015 Elsevier Ltd.All rights reserved. Source

Madronero A.,CSIC - National Center for Metallurgical Research | Robla J.,CSIC - National Center for Metallurgical Research | Garcia-Hierro J.,CSIC - National Center for Metallurgical Research | Martin-Gonzalez M.S.,IMM CSIC | And 2 more authors.
Journal of Materials Science: Materials in Electronics | Year: 2012

The Seebeck coefficient of vapour grown carbon fibres and carbon fibres made from polyacryolytrile precursor has been studied as a possible parameter to control hydrogen storage inside. The sign of the Seebeck coefficient gives the sign of the dominant charge carriers in the fibres, and when hydrogen is absorbed by the carbonaceous material, mainly as H +, it acts as a positive charge carrier. A simple two-band electronic model has been considered to explain the influence of hydrogenation on the Seebeck's coefficient of these carbon microfibres. The most favourable condition for hydrogen adsorption is a moderately low pressure of hydrogen. Furthermore, it was observed that outgassing is more pronounced than expected in some types of fibres, thereby supporting the proposed presence of hydrogen generated during the manufacturing process. © Springer Science+Business Media, LLC 2012. Source

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