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De Arespacochaga N.,Water Technology Center aqua | Valderrama C.,Polytechnic University of Catalonia | Peregrina C.,CIRSEE Suez Environnement | Hornero A.,Water Technology Center aqua | And 3 more authors.
Fuel Processing Technology | Year: 2015

The application of high-temperature fuel cells in Waste Water Treatment Plants (WWTPs) combines a high-efficiency electricity generation technology and a renewable fuel, thus simultaneously mitigating greenhouse gas emissions and resource depletion. This study investigates the current applicability and limitations of biogas-powered Molten Carbonate Fuel Cells (MCFCs) Solid Oxide Fuel Cells (SOFCs) and compares them with Internal Combustion Engines (ICEs) and micro-turbines (MTs). Operational data from six industrial-scale plants and from a pilot plant was collected to simulate the performance of these Energy Conversion Systems in twelve scenarios, built based on two WWTP sizes (100,000 and 500,000 PE) and two biogas qualities (H2S 2500 and 250ppmv). Comparisons were focused on technical (Normalized Saved Fossil Energy and percentage of energy self-sufficiency) and economic (Levelized Cost of Energy and Payback Period/Internal Rate of Return) indicators. MCFCs showed the highest technical performance, improving the electrical self-sufficiency of the WWTP around 60% compared to conventional cogeneration. However, to date, ICEs are still the most economically profitable alternative, as payback periods of fuel cell projects are 4 times larger. The high investment cost and the low stack durability are the key parameters to be improved for industrial deployment of fuel cell systems in WWTPs. © 2015 Elsevier B.V.

Le Hyaric R.,INSA Lyon | Canler J.-P.,IRSTEA | Barillon B.,CIRSEE Suez Environnement | Naquin P.,British Petroleum | Gourdon R.,INSA Lyon
Bioresource Technology | Year: 2010

The anaerobic digestion of screenings from a municipal wastewater treatment plant was studied in a 90L pilot-scale digester operated at 35°C under semi-continuous conditions. In the first 4weeks, a dry solids residence time of 28days was applied, but the installation of inhibitory conditions was observed. Feeding was therefore suspended for 4weeks to allow the digester to recover from inhibition, and then progressively increased up to a constant load of 6kg of raw waste per week, corresponding to an average residence time of about 35days of dry solids. At this stage, biogas production stabilized between 513 and 618Nl/kg VSadded per week, with methane contents around 61% v/v. The results of this work thereby supported the feasibility of (co-)digestion as a potential alternative treatment of screenings from municipal wastewater treatment plants. © 2010 Elsevier Ltd.

Aubry D.,Ecole Centrale Paris | Boudon J.,CIRSEE Suez Environnement | Paradinas T.L.,Ondeo Systems
Urban Water Management: Challenges and Oppurtunities - 11th International Conference on Computing and Control for the Water Industry, CCWI 2011 | Year: 2011

The first purpose of this paper is to show how the equations of hydraulics and chlorine transport through networks may be approximated by the finite element method and thus benefit from all the software environment (CAD, meshing, solvers...) usually provided in FEM softwares. Thus even complex highly meshed networks can be considered without any difficulty. The second part then deals with the inverse problems of parameter identification such as discharge coefficient, leakage location, reaction parameter. In each case, an adjoint state is built from a regularized misfit function which measures the distance between the experimental data and the simulation. A Lagrangian formulation provides the necessary optimal equations that the unknown parameters must satisfy. Some preliminary numerical applications illustrate the high potentialities of the proposed approach.

Becouze-Lareure C.,INSA Lyon | Dembele A.,INSA Lyon | Coquery M.,IRSTEA | Cren-Olive C.,French National Center for Scientific Research | And 2 more authors.
Urban Water Journal | Year: 2015

Contaminants in urban wet weather discharges originate from a number of sources such as materials from wet and dry atmospheric deposition, wastewaters, urban surface erosion, traffic-related activities, in-sewer deposits, etc. In the current study, four contributions (rainwater, dry atmospheric deposition, dry weather discharge and catchment surface + possible erosion of in-sewer deposits) to the total concentrations of priority substances have been assessed at the outlet of two urban catchments (one residential catchment with a combined system and one industrial area with a separate stormwater system) for 12 storm events (six for each catchment). Mass balances were calculated for seven metals and four pesticides, as well as for total suspended solids and chemical oxygen demand. The respective contributions of dry and wet atmospheric deposition, wastewater and catchment surface differ for each pollutant type, corresponding to different land use, activities, environments and sewer systems. For most of the pollutants, the catchment surface appears to be the main contribution, with significant storm event variability, excepted for atrazine in one catchment. © 2015 Taylor & Francis

Coquery M.,IRSTEA | Pomies M.,IRSTEA | Martin-Ruel S.,CIRSEE Suez Environnement | Budzinski H.,University of Bordeaux 1 | And 4 more authors.
Techniques - Sciences - Methodes | Year: 2011

The Amperes project allowed to evaluate concentrations and fluxes of 127 priority and emerging substances in influent and effluent wastewaters as well as sludge, using rigorous and validated sampling and analytical methodologies, for various types of treatment processes selected as representative of the French wastewater treatment plants (WWTP). In total, 21 WWTP were selected to study biological secondary treatments, several tertiary treatments and sludge treatments. Average 24h composite samples were collected for 2-3 consecutive days during dry weather in WWTP influent and effluent. In order to measure dissolved and particulate substances, we developed and applied specific analytical methods, sensitive and adapted to complex wastewater and sludge matrices. The substances with concentrations above 1 μg/L in influent wastewaters are DEHP, some volatile organics (VOC), flame retardants (PBDE), alkylphenols and nonylphenols polyethoxylates, and almost all metals. Concentration levels and specific fluxes in influent showed a specificity for WWTP influent of rural areas compared to urban areas for some industrial substances (alkylphenols, VOC, chloroalkanes, dichlorophenol, bisphenol A and some metals). In secondary treated wastewaters, even if a significant decrease of concentrations was observed compared to influents, 12 priority substances, 10 of the other organic substances and almost all metals were quantified with mean concentrations above 0,1 μg/L. Concentrations above 1 μg/L were frequently measured for several metals, DEHP and some degradation products (4-NP1EC et AMPA). Almost all substances that were quantified in influent were also quantified in sludge, although concentrations could be very low, especially for hydrophilic substances (pesticides). This paper also presents data on specific fluxes (μg/d/inh) emitted towards receiving aquatic systems.

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