Search results for "INGENIERIA HIDRAULICA"
showing 10 items of 58 documents
Sub-critical filtration conditions of commercial hollow-fibre membranes in a submerged anaerobic MBR (HF-SAnMBR) system: The effect of gas sparging i…
2012
A submerged anaerobic MBR demonstration plant with two commercial hollow-fibre ultrafiltration systems (PURON®, Koch Membrane Systems, PUR-PSH31) was operated using municipal wastewater at high levels of mixed liquor total solids (MLTS) (above 22gL -1). A modified flux-step method was applied to assess the critical flux (J C) at different gas sparging intensities. The results showed a linear dependency between J C and the specific gas demand per unit of membrane area (SGD m). J C ranged from 12 to 19LMH at SGD m values of between 0.17 and 0.5Nm 3h -1m -2, which are quite low in comparison to aerobic MBR. Long-term trials showed that the membranes operated steadily at fluxes close to the est…
Experimental study of the anaerobic urban wastewater treatment in a submerged hollow-fibre membrane bioreactor at pilot scale
2011
The aim of this study was to assess the effect of several operational variables on both biological and separation process performance in a submerged anaerobic membrane bioreactor pilot plant that treats urban wastewater. The pilot plant is equipped with two industrial hollow-fibre ultrafiltration membrane modules (PURON¿ Koch Membrane Systems, 30m 2 of filtration surface each). It was operated under mesophilic conditions (at 33°C), 70days of SRT, and variable HRT ranging from 20 to 6h. The effects of the influent COD/SO 4-S ratio (ranging from 2 to 12) and the MLTS concentration (ranging from 6 to 22gL -1) were also analysed. The main performance results were about 87% of COD removal, efflu…
Optimising an outdoor membrane photobioreactor for tertiary sewage treatment
2019
[EN] The operation of an outdoor membrane photobioreactor plant which treated the effluent of an anaerobic membrane bioreactor was optimised. Biomass retention times of 4.5, 6, and 9 days were tested. At a biomass retention time of 4.5 days, maximum nitrogen recovery rate:light irradiance ratios, photosynthetic efficiencies and carbon biofixations of 51.7¿±¿14.3¿mg¿N·mol¿1, 4.4¿±¿1.6% and 0.50¿±¿0.05¿kg CO2·m3influent, respectively, were attained. Minimum membrane fouling rates were achieved when operating at the shortest biomass retention time because of the lower solid concentration and the negligible amount of cyanobacteria and protozoa. Hydraulic retention times of 3.5, 2, and 1.5 days …
Outdoor microalgae-based urban wastewater treatment: recent advances, applications and future perspectives
2021
[EN] Although microalgae-based wastewater treatment has been traditionally carried out in extensive waste stabilization ponds, recent trends focus on the use of microalgae to apply the circular economy principles in the wastewater treatment sector due to the capacity of algae to absorb carbon dioxide while recovering nutrients from sewage. To this aim, the development of new intensive microalgae-based systems with higher efficiency and level of process control is required. Results obtained for these systems at lab scale are generally promising. However, upscaling to outdoor conditions is often uncertain. Some advances have been made in terms of applying open systems at large scale. However,…
Hydrogeomorphological analysis and modelling for a comprehensive understanding of flash-flood damage processes: the 9 October 2018 event in northeast…
2020
31 Pags.- 12 Figs.- 5 Tabls. © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License.
Effect of light intensity, light duration and photoperiods in the performance of an outdoor photobioreactor for urban wastewater treatment
2019
[EN] A series of eight experiments were carried out to analyse the effects of light intensity, light duration and photoperiods on a microalgae culture for treating AnMBR effluent at an outdoor photobioreactor (PBR) plant. Improved performance was achieved in terms of nutrient recovery rates, biomass productivity and effluent nutrient concentrations at a higher net photon flux. However, the higher irradiance was also responsible for lower biomass productivity:light irradiance ratios. None of the experiments with different lighting regimes and the same net photon flux showed any significant differences. The data obtained suggest that microalgae performance in this system did not depend on the…
Performance of an outdoor membrane photobioreactor for resource recovery from anaerobically treated sewage
2018
[EN] The objective of this work was to evaluate the performance of a pilot scale membrane photobioreactor (MPBR) for treating the effluent of an anaerobic membrane bioreactor (AnMBR) system. In particular, new experimental data on microalgae productivity, nutrient recovery, CO2 biofixation and energy recovery potential was obtained under different operating conditions, which would facilitate moving towards cost-effective microalgae cultivation on wastewater. To this aim, a 2.2-m(3) MPBR equipped with two commercial-scale hollow-fibre ultrafiltration membrane modules was operated treating the nutrient-loaded effluent from an AnMBR for sewage treatment. The influence of several design, enviro…
Dataset to assess the shadow effect of an outdoor microalgae culture
2019
[EN] This data in brief (DIB) article is related to a Research article [1]. Microalgae biomass absorb the light photons that are supplied to the culture, reducing the light availability in the inner parts of the photobioreactors. This is known as self-shading or shadow effect. This effect has been widely studied in lab conditions, but information about self-shading in outdoor photobioreactors is scarce. How this shadow effect affects the light availability in an outdoor photobioreactor was evaluated. In addition, advantages and disadvantages of different artificial light sources which can overcome light limitation are described.
Comprehensive assessment of the microalgae-nitrifying bacteria competition in microalgae-based wastewater treatment systems: Relevant factors, evalua…
2022
[EN] Due to their capacity to assimilate carbon dioxide and nutrients, microalgae-based cultivation systems have emerged as a green solution for intensive wastewater treatment. However, when large concentrations of ammonium are present the competition between microalgae and ammonium-oxidising bacteria plays a significant role. Microalgae use ammonium to synthesise proteins, photosynthetic pigments and nucleic acids, while ammonium-oxidising bacteria use it as a source of electrons and oxidise it to nitrite.Several authors have studied the isolated factors that influence microalgae-nitrifying bacteria competition, although a comprehensive analysis of this interesting topic is still lacking. …
Un nuevo híbrido del género Ophrys L. (Orchidaceae) en el litoral valenciano
2012
[EN] Here we describe a new hybrid of genus Ophrys L. (Orchidaceae) found in Cullera (Valencia): Ophrys x donatiae, which comes from the crossing between Ophrys dianica and O. tenthredinifera, and has intermediate characters. Distribution area and phenology are shared by parental plants.