Search results for " reactor"
showing 10 items of 361 documents
The metabolic versatility of PAOs as an opportunity to obtain a highly P-enriched stream for further P-recovery
2015
The effects of two sequencing batch reactor operation strategies for phosphorus stream enrichment over the biological phosphorus removal performance have been studied. The objective of both strategies is of performing an extraction cycle in order to obtain a new stream highly enriched with phosphorus. In the 1st strategy the amount of influent volatile fatty acids (VFAs) is the same in each cycle; while in the 2nd strategy the influent VFAs concentration is increased during phosphorus extraction experiments. Despite the strong decrease of the stored poly-P inside the cells in both strategies after the recovery cycles, the ability of the systems to remove phosphorus was not affected. The P-r…
Photocatalytic Processes in Membrane Reactors
2010
Conversion and degradation processes of various substrates in various types of matrices using both artificial and solar light are today very attractive by considering the scarcity and the expensiveness of the conventional energy sources. Coupling of membrane with light has shown to be very powerful and promising hybrid process, especially because a synergistic effect has been often observed. Some examples of reactions carried out to produce useful chemicals or to degrade noxious species in the framework of the green chemistry approach are reported. Fundamentals of heterogeneous photocatalysis, in general, and photocatalytic reactions in membrane reactors, in particular, are treated with a f…
A constitutive model for the thermo-mechanical behaviour of fusion-relevant pebble beds and its application to the simulation of HELICA mock-up exper…
2007
Abstract Within the framework of the R&D activities promoted by EFDA on the Helium-Cooled Pebble Bed Test Blanket Module to be irradiated in ITER, attention has been focused on the modelling of the thermo-mechanical behaviour of both beryllium and lithiated ceramic pebble beds that are envisaged to be used respectively as neutron multiplier and tritium breeder. This behaviour depends, mainly, on the reactor-relevant conditions, the pebble sizes and the breeder cell geometries and a general constitutive model has not yet been validated, especially for fusion-relevant applications. ENEA-Brasimone and the Department of Nuclear Engineering (DIN) of the University of Palermo have performed inten…
Start-Up of Chitosan-Assisted Anaerobic Sludge Bed Reactors Treating Light Oxygenated Solvents under Intermittent Operation
2021
Quality of the granular sludge developed during the start-up of anaerobic up-flow sludge bed reactors is of crucial importance to ensure the process feasibility of treating industrial wastewater such as those containing solvents. In this study, the microbial granule formation from suspended-growth biomass was investigated in two chitosan-assisted reactors. These reactors operated mimicking industrial sites working with night closures treating a mixture of ethanol, ethyl acetate, and 1-ethoxy-2-propanol. Each reactor operated under different hydrodynamic regimes typical from UASB (R1: <
Evaluation of activated sludge model no.2 at high phosphorus concentrations
2001
This paper presents laboratory scale experimentation carried out to study enhanced biological phosphorus removal at high phosphorus concentrations in a sequencing batch reactor. Four series of data obtained in a sequencing batch reactor are examined in light of the Activated Sludge Model No. 2. This model was calibrated using data from the first and second series working at low phosphorus concentrations. The Activated Sludge Model No. 2 successfully characterised the enhanced biological phosphorus removal performance of the sequencing batch reactor at low phosphorus concentrations. The calibrated model was then used to adjust experimental results of the other series working at high phosphor…
Analysis of a Station Black-Out transient in SMR by using the TRACE and RELAP5 code
2014
The present paper deals with the investigation of the evolution and consequences of a Station Black-Out (SBO) initiating event transient in the SPES3 facility [1]. This facility is an integral simulator of a small modular reactor being built at the SIET laboratories, in the framework of the R&D program on nuclear fission funded by the Italian Ministry of Economic Development and led by ENEA. The SBO transient will be simulated by using the RELAP5 and TRACE nodalizations of the SPES3 facility. Moreover, the analysis will contribute to study the differences on the code predictions considering the different modelling approach with one and/or three-dimensional components and to compare the capa…
TRIGA-SPEC: the prototype of MATS and LaSpec
2015
Investigation of short-lived nuclei is a challenging task that MATS and LaSpec will handle at the low energy branch of Super-FRS at FAIR. The groundwork for those experiments is laid-out already today at the TRIGA-SPEC facility as a powerful development platform located at the research reactor TRIGA Mainz. The latest status, new developments and first results of commissioning runs are presented here.
Effect of organic loading rate on the production of Polyhydroxyalkanoates from sewage sludge
2023
The aim of this work was to study the effect of organic loading rate on the production of Polyhydroxyalkanoates (PHA) from sewage sludge. Synthesis of PHA using sewage sludge as platform was achieved in this work. Three pilot-scale selection-sequencing batch reactors (S-SBR) were used for obtaining a culture able to accumulate PHA following a strategy of aerobic dynamic feeding (ADF) at different volumetric organic-loading-rate (vOLR): 1.3, 1.8 and 0.8 g COD L-1 d-1 for S-SBR 1, S-SBR 2 and S-SBR 3, respectively. Decreasing the vOLR enhanced the general performance of the process as for organic matter removal (from 99.2% ± 0.3% in S-SBR-3 to 92 ± 2 in S-SBR-2) while the opposite trend was r…
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…