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Barcelona, Spain

Velasco M.,aqua Water Technology Center | Cabello A.,aqua Water Technology Center | Russo B.,Aqualogy | Russo B.,University of Zaragoza
Urban Water Journal | Year: 2016

This paper presents a detailed flood damage assessment in the Raval district of Barcelona. The implementation of a new 1D-2D coupled model is used to obtain flood depths, and new stage damage curves are developed to estimate the direct tangible damages. The curves have been validated using data from surveys and actual reported damages to the Spanish re-assurance. Finally, combining hazard and vulnerability levels by using a GIS-based toolbox, the expected annual damage of the area is obtained. This enables the determination of the critical points of the district in terms of flooding impacts, and highlights the need to implement strategies to cope with these impacts. © 2015 Taylor & Francis.

Ibarra D.,Aqualogy | Arnal J.,University of Alicante
Journal of Water Resources Planning and Management | Year: 2014

Most of the energy consumed by a water company is used to operate pumping systems. Identifying the optimal schedule for such systems in near real time will drastically reduce energy costs. The pump scheduling problem comprises three main elements: the pumping system, the tank, and the water demand to be satisfied. In this paper, a mathematical programming model and techniques used to solve this problem are presented. This study analyzed a parallel programming paradigm to solve this problem by introducing stochastic programming techniques (scenario tree evaluation) and multisite problems. Numerical experiments were designed and completed on parallel computers combining classical mathematical programming techniques and parallel tools. As a result, the parallel programming strategy was experimentally proven to be a useful technique for near-real-time pump scheduling applications. © 2014 American Society of Civil Engineers.

Stephenson M.,Aqualogy
International No-Dig Madrid 2014 | Year: 2014

Ice Pigging is a new pipe cleaning method that uses slush ice to remove biofilm and sediment from the inside of pressurized pipes. It can be used in drinking water networks to effectively remove biofilms and reduce the incidence of discolouration events, and on sewer rising mains to remove accumulated deposits to improve pumping efficiency. The introduction of ice pigging in the pipeline industry represents a major shift in the way that pipes can be cleaned, operated, or prepared for use. The benefits of using ice are numerous. It can be inserted into pipes via existing fittings like fire hydrants, is as effective as swabbing, is very fast - the process is normally measured in minutes and hours - and carries virtually no risk as the ice is harmless. In the unusual event of an issue the ice will eventually melt. Copyright © 2014 ISTT.

de Arespacochaga N.,Water Technology Center aqua | Valderrama C.,Polytechnic University of Catalonia | Mesa C.,Water Technology Center aqua | Bouchy L.,Aqualogy | Cortina J.L.,Water Technology Center aqua
Chemical Engineering Journal | Year: 2014

The most harmful biogas contaminant for energy conversion equipment such as fuel cells is hydrogen sulphide (H2S); thus efficient and cost-effective treatment systems for this compound should be designed and developed. A pilot-scale biotrickling filter (BTF) working in acidic media (pH=1.5-2) was operated for raw sewage biogas desulphurisation. Its operational performance as a function of two key important process parameters (temperature and retention time) was evaluated through short-term experimentation; showing that H2S removal efficiencies greater than 90% can be obtained at temperatures of 30°C, retention times of 80-85s and H2S Loading Rates of 210gH2S/(m3bedh). The system was afterwards operated for 924h and showed an average elimination capacity of 169gH2S/(m3bedh) at an average removal efficiency of 84%. The unit proved to be reversible to the effect of operation disruptions (lack of temperature control, limitations on oxygen supply), which were introduced to simulate possible system miss functioning or operational failures. Nevertheless, partial oxidation to elemental sulphur (S(s)) accounted for 70% of H2S removal progressively increasing the pressure drop over the column; reducing the availability of the treatment line and eventually leading to fuel cell shutdowns. More efficient systems for oxygen supply and solids removal are the key factors to be addressed for a sustainable deployment of BTF technology in waste water treatment plants (WWTP). © 2014 Elsevier B.V.

De Arespacochaga N.,Water Technology Center aqua | Valderrama C.,Polytechnic University of Catalonia | Peregrina C.,CIRSEE | Mesa C.,Water Technology Center aqua | And 2 more authors.
Journal of Power Sources | Year: 2015

Biogas from anaerobic digestion of organic matter is a promising renewable energy source and fuel cells appear as a breakthrough technology to improve the performance of the biogas-to-energy valorisation chain. The vast majority of studies addressing biogas energy recovery through Solid Oxide Fuel Cells published in recent years correspond to simulations and lab-scale performance with synthetic biogas. This paper assesses the pilot performance of a 2.8 kWe SOFC unit powered with cleaned sewage biogas for around 700 h in a Wastewater Treatment Plant. The biogas thorough treatment consisting of a biological desulphurisation with a biotrickling filter followed by a deep cleaning step based on adsorption is successful for removing sulphur compounds, siloxanes and hydrocarbons. The influence of the heat-to-power ratio on fuel cell performance is investigated operating the system at O/C ratio of 2, reforming temperature of 550 °C, stack temperature of 800 °C and at a constant voltage of 43 V. At optimized conditions for electrical production satisfying heat demand in the WWTP, system electrical and thermal efficiencies account for 34% and 28%. Cogeneration efficiency remains constant at around 59-62% for all the heat-to-power ratios tested. Furthermore, the impact of the oxygen content in the biogas is also studied. © 2015 Elsevier B.V. All Rights Reserved.

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