Coordinateur PR2I Environnement AMU
Responsable Axe 4, Fédération de Recherche ECCOREV
Membre du CS du Parc National des Calanques
Membre du CS de l’OSU PYTHEAS
Membre du GDRI ICEINT
Administrateur Société Française de Génie des Procédés, du Pôle de Compétitivité Eau, du CRITT Chimie et du PRIDES Green
Président du Comité Exécutif de la Revue des Sciences de l'Eau
Membre du copil Sud-Est des assises du Génie des Procédés
Activités
Application des méthodes du Génie des Procédés au traitement des eaux et des déchets :
Procédés de traitement des eaux usées
Valorisation des boues
Rhéologie des boues
Réutilisation des Eaux
Modélisation, simulation, optimisation
Publications scientifiques au M2P2
2018
Hiba Souissi, Raphael Zory, Julien Boudarham, Didier Pradon, Nicolas Roche, et al.. Muscle force strategies for poststroke hemiparetic patients during gait. Topics in Stroke Rehabilitation, 2018, 26 (1), pp.58-65. ⟨10.1080/10749357.2018.1536023⟩. ⟨hal-02506537⟩ Plus de détails...
Hiba Souissi, Raphael Zory, Jonathan Bredin, Nicolas Roche, Pauline Gerus. Co-contraction around the knee and the ankle joints during post-stroke gait.. European Journal of Physical and Rehabilitation Medicine, 2018, 54 (3), pp.380-387. ⟨10.23736/S1973-9087.17.04722-0⟩. ⟨hal-02506559⟩ Plus de détails...
Impairments resulting from hemiparetic stroke lead to persistent difficulties with walking. Abnormal co-contraction patterns of lower limb muscles might be a compensatory mechanism to deal with its resulting gait impairments.
Hiba Souissi, Raphael Zory, Jonathan Bredin, Nicolas Roche, Pauline Gerus. Co-contraction around the knee and the ankle joints during post-stroke gait.. European Journal of Physical and Rehabilitation Medicine, 2018, 54 (3), pp.380-387. ⟨10.23736/S1973-9087.17.04722-0⟩. ⟨hal-02506559⟩
Journal: European Journal of Physical and Rehabilitation Medicine
Cristian Barca, Stephane Troesch, Yves Andres, Florent Chazarenc, Nicolas Roche. Modelling hydrodynamics of horizontal flow steel slag filters designed to upgrade phosphorus removal in small wastewater treatment plants. Journal of Environmental Management, 2018, 206, pp.349-356. ⟨10.1016/j.jenvman.2017.10.040⟩. ⟨hal-02111630⟩ Plus de détails...
Steel slag filters, if well designed and operated, may upgrade phosphorus removal in small wastewater treatment plants such as stabilization ponds and constructed wetlands. The main objective of this study was to develop a systemic modelling approach to describe changes in the hydraulic performances and internal hydrodynamics of steel slag filters under real dynamic operating conditions. The experimental retention time distribution curves (RTD curves) determined from tracer experiments performed at different times during the first year of operation of two field-scale steel slag filters were analyzed through a three stage process. First, a statistical analysis of the RTD curves was performed to determine statistical parameters of the retention time distribution. Second, classical tanks in series (TIS) and plug flow with dispersion (PFD) models were used to obtain a first evaluation of the dispersion and mixing regime. Finally, a multi-flow path TIS model, based on the assumption of several flow paths with different hydraulic properties, is proposed to accurately describe the internal hydrodynamics. Overall, the results of this study indicate that higher CaO content, round shape, and larger grain size distribution of steel slag may promote plug-like flow rather than dispersion. The results of the multi-flow path TIS model suggest that the internal hydrodynamics of steel slag filters can be primarily described by two main flow paths: (i) a faster main flow path showing higher plug flow, followed by (ii) a slower secondary flow path showing higher dispersion. The results also showed that internal hydrodynamics may change over time as a consequence of physical-chemical phenomena occurring in the filter, including accumulation of precipitates, slag hydration and carbonation, and particle segregation.
Cristian Barca, Stephane Troesch, Yves Andres, Florent Chazarenc, Nicolas Roche. Modelling hydrodynamics of horizontal flow steel slag filters designed to upgrade phosphorus removal in small wastewater treatment plants. Journal of Environmental Management, 2018, 206, pp.349-356. ⟨10.1016/j.jenvman.2017.10.040⟩. ⟨hal-02111630⟩
N. Rizk, N. Ait-Mouheb, G. Bourrier, Bruno Molle, Nicolas Roche. Parameters controlling chemical deposits in micro-irrigation with treated wastewater. Journal of Water Supply: Research and Technology - AQUA, 2017, 66 (8), pp.587 - 597. ⟨10.2166/aqua.2017.065⟩. ⟨hal-01665983⟩ Plus de détails...
Micro-irrigation with treated wastewater has the potential to be the most efficient irrigation technique, especially in water scarce areas. Its main disadvantage is the high sensitivity of the drippers to clog. This study focused only on the chemical precipitation mechanisms. In a batch chemical process in parallel with PHREEQC software, two temperatures (22 and 55°C), four pH (8, 8.5, 9 and 9.5) and CO2 partial pressure were tested. The aim was to analyze the quantity of precipitates and their crystalline nature and calculate the effects of these factors on the behavior of dissolved chemical elements in treated wastewater to be able to validate and calibrate a geochemical software in order to predict chemical precipitation. The amount of precipitate increases by increasing pH and temperature. Precipitates were analyzed using thermo gravimetric analysis (TGA) and X-ray diffraction (XRD). Calcium carbonate (CaCO3) in the form of calcite was found to be the predominant precipitate. Experimental and model results showed that the saturation index (SI) of calcite was found to be the factor that most frequently affected calcite precipitation. Calcite SI is pH, temperature and CO2 partial pressure dependent. In the case of irrigation, water equilibrium with atmospheric CO2 minimizes precipitation of calcite.
N. Rizk, N. Ait-Mouheb, G. Bourrier, Bruno Molle, Nicolas Roche. Parameters controlling chemical deposits in micro-irrigation with treated wastewater. Journal of Water Supply: Research and Technology - AQUA, 2017, 66 (8), pp.587 - 597. ⟨10.2166/aqua.2017.065⟩. ⟨hal-01665983⟩
Journal: Journal of Water Supply: Research and Technology - AQUA
Camille Grandclement, Isabelle Seyssiecq, Anne Piram, Pascal Wong-Wah-Chung, Guillaume Vanot, et al.. From the conventional biological wastewater treatment to hybrid processes, the evaluation of organic micropollutant removal: A review. Water Research, 2017, 111, pp.297-317. ⟨10.1016/j.watres.2017.01.005⟩. ⟨hal-01456484⟩ Plus de détails...
Because of the recalcitrance of some micropollutants to conventional wastewater treatment systems, the occurrence of organic micropollutants in water has become a worldwide issue, and an increasing environmental concern. Their biodegradation during wastewater treatments could be an interesting and low cost alternative to conventional physical and chemical processes. This paper provides a review of the organic micropollutants removal efficiency from wastewaters. It analyses different biological processes, from conventional ones, to new hybrid ones. Micropollutant removals appear to be compound-and process-dependent, for all investigated processes. The influence of the main physico-chemical parameters is discussed, as well as the removal efficiency of different microorganisms such as bacteria or white rot fungi, and the role of their specific enzymes. Even though some hybrid processes show promising micropollutant removals, further studies are needed to optimize these water treatment processes, in particular in terms of technical and economical competitiveness.
Camille Grandclement, Isabelle Seyssiecq, Anne Piram, Pascal Wong-Wah-Chung, Guillaume Vanot, et al.. From the conventional biological wastewater treatment to hybrid processes, the evaluation of organic micropollutant removal: A review. Water Research, 2017, 111, pp.297-317. ⟨10.1016/j.watres.2017.01.005⟩. ⟨hal-01456484⟩
Martine Poux, Nicolas Roche. Selected Papers from the 10th European Congress of Chemical Engineering – ECCE10 – Nice, France. Canadian Journal of Chemical Engineering, 2017, 95 (2), pp.207. ⟨10.1002/cjce.22685⟩. ⟨hal-01456497⟩ Plus de détails...
Biochemical Engineering Sciences (ESBES). Approximately 1800 people from all around the world (67 nationalities) attended the conference. The participation of industrialists (25 %) and students (31 %) was remarkable. The scientific program was impressive, being composed of 5 symposia, 4 workshops, 6 plenary lectures, 82 keynotes, and more than 700 oral communications organized in 202 sessions and 900 poster communications. These covered vast chemical and biochemical engineering topics, which reflected the latest scientific trends in their field and several special issues of different peer-reviewed journals will be published.
Martine Poux, Nicolas Roche. Selected Papers from the 10th European Congress of Chemical Engineering – ECCE10 – Nice, France. Canadian Journal of Chemical Engineering, 2017, 95 (2), pp.207. ⟨10.1002/cjce.22685⟩. ⟨hal-01456497⟩
Victor S Ruys, Kamel S Zerari, Isabelle S Seyssiecq, Nicolas Roche. Study of Carbonaceous and Nitrogenous Pollutant Removal Efficiencies in a Hybrid Membrane Bioreactor. Journal of Chemistry , 2017, 2017, pp.1 - 7. ⟨10.1155/2017/4080847⟩. ⟨hal-01536019⟩ Plus de détails...
A hybrid membrane bioreactor (HMBR) comprises activated sludge (free biomass), a biofilm (supported biomass), and a membrane separation. A laboratory pilot-scale HMBR was operated for seven months with high organic loads of both carbonic and nitrogen pollutants. Several experiments were conducted to investigate the influence of the height of the packing bed (27 cm, 50 cm, and 0 cm) and the effect of the concentration of dissolved oxygen (DO) on the organic removal rate, total nitrogen removal rate (TN), and ammonium removal. The organic removal rate was always >95% and mostly >98%. The NH 4 +-N and TN removal rates were directly related to DO. NH 4 +-N removal rate reached 100% and was mostly >99% with a concentration of DO > 0.1 mg/L, whereas the NO 3 −-N removal rate was differentially affected depending on the level of DO. The removal rate increased when the concentration of DO was optimal for simultaneous nitrification and denitrification, which was between 0.1 and 0.5 mg/l, and the TN removal rate was consequently high. The removal rate decreased when DO was high and denitrification was consequently low thereby reducing the TN removal rate. This implies that high levels of DO (>1 mg/L) limit the denitrification process and low levels of DO (<0.1 mg/L) limit the nitrification process and hence total nitrogen removal in the bioreactor.
Victor S Ruys, Kamel S Zerari, Isabelle S Seyssiecq, Nicolas Roche. Study of Carbonaceous and Nitrogenous Pollutant Removal Efficiencies in a Hybrid Membrane Bioreactor. Journal of Chemistry , 2017, 2017, pp.1 - 7. ⟨10.1155/2017/4080847⟩. ⟨hal-01536019⟩
Martine Poux, Nicolas Roche. Chemical and biochemical engineering for a new sustainable process industry in Europe. Chemical Engineering Research and Design, 2016, Chemical Engineering Research and Design, 115 (Part B ), pp.261. ⟨10.1016/j.cherd.2016.10.037⟩. ⟨hal-01458420⟩ Plus de détails...
The very title itself was the slogan of the main scientific event in Chemical Engineering in Europe, held in Nice in September 2015, which combined the 10th European Congress of Chemical Engineering (ECCE10), the 3rd European Congress of Applied Biotechnology (ECAB3) and the 5th European Process Intensification Conference (EPIC5). These events were organised by the French Society of Chemical Engineering (SFGP) and Live! By GL under the auspices of the European Federation of Chemical Engineering (EFCE) and the European Society of Biochemical Engineering Sciences (ESBES). The conference focused on four main societal challenges: - Energy: new and unconventional resources, conservation and management - Water management and treatment - Biotechnology and food - Industrial ecosystems and addressed fundamental chemical and biochemical engineering research.
Martine Poux, Nicolas Roche. Chemical and biochemical engineering for a new sustainable process industry in Europe. Chemical Engineering Research and Design, 2016, Chemical Engineering Research and Design, 115 (Part B ), pp.261. ⟨10.1016/j.cherd.2016.10.037⟩. ⟨hal-01458420⟩
Jadwiga Wedzicha, Donald Banerji, Kenneth Chapman, Jorgen Vestbo, Nicolas Roche, et al.. Indacaterol–Glycopyrronium versus Salmeterol–Fluticasone for COPD. New England Journal of Medicine, 2016, 374 (23), pp.2222 - 2234. ⟨10.1056/NEJMoa1516385⟩. ⟨hal-01872709⟩ Plus de détails...
Jadwiga Wedzicha, Donald Banerji, Kenneth Chapman, Jorgen Vestbo, Nicolas Roche, et al.. Indacaterol–Glycopyrronium versus Salmeterol–Fluticasone for COPD. New England Journal of Medicine, 2016, 374 (23), pp.2222 - 2234. ⟨10.1056/NEJMoa1516385⟩. ⟨hal-01872709⟩
Salah Akkache, Ana-Belen Hernandez, Gabriel Teixeira, Franck Gelix, Nicolas Roche, et al.. Co-gasification of wastewater sludge and different feedstock: Feasibility study. Biomass and Bioenergy, 2016, 89, pp.201 - 209. ⟨10.1016/j.biombioe.2016.03.003⟩. ⟨hal-01458422⟩ Plus de détails...
Gasification experiments were performed for several feedstocks alone (wastewater sludge, waste wood, reeds, olive pomace, solid recovered fuel, paper labels and plastic labels) using a fixed bed reactor operating in semi-batch conditions. In order to combine them in an optimal gasifying blend, the gasification behavior of each feedstock was compared with that of wastewater sludge through the following criteria: the raw feedstock proximate and ultimate composition, the solid conversion, the gas heating value, the pollutants release and the ashes melting. Operated alone, the conversion rate of the feedstocks after 58 min of solid residence time was over 77% of initial mass. The Syngas low heating value produced at 1123 K was in the range of 9.0 to 11.9 MJ m À3. The major concerns regarding the wastewater sludge were the pollutants precursors' release (NH 3 , COS…) and the ash slagging and fouling. The calculated slagging and fouling indexes were high also for olive pomace and for waste wood. Finally, among the possible blends studied the paper labels and plastic labels can be co-gasified with secondary and digested wastewater sludge without any restriction, reeds and solid recovered fuel can be blinded with secondary wastewater sludge without any restriction, a specific attention have to be taken to fouling when they are blended with digested wastewater sludge. The blend based on waste wood and olives pomace should be avoided for instance due to their ash slagging and fouling tendency.
Salah Akkache, Ana-Belen Hernandez, Gabriel Teixeira, Franck Gelix, Nicolas Roche, et al.. Co-gasification of wastewater sludge and different feedstock: Feasibility study. Biomass and Bioenergy, 2016, 89, pp.201 - 209. ⟨10.1016/j.biombioe.2016.03.003⟩. ⟨hal-01458422⟩
S. Gamri, A. Soric, Séverine Tomas, Bruno Molle, Nicolas Roche. Effects of pipe materials on biofouling under controlled hydrodynamic conditions. Journal of Water Reuse and Desalination, 2016, 6 (1), pp.167-174. ⟨10.2166/wrd.2015.037⟩. ⟨hal-01665987⟩ Plus de détails...
Experiments were carried out to investigate pipe material impacts on biofouling, at high effluent concentration levels and under controlled hydrodynamic conditions. Two velocities (0.4 and 0.8 m s-1) were used to monitor biofilm growth on polyethylene (PE) and polyvinylchloride (PVC) pipe walls, respectively. These conditions were established based on wastewater irrigation practices. A decrease in biomass is observed after 49 days of experiments for both velocities and may be related to biofilm detachment. Biofilm growth is greater at 0.8 m s-1. For both velocities, PVC is less sensitive to biofilm growth than PE. Pipe straightness plays a primary role in biofilm growth control. This effect is more significant than pipe surface characteristics (roughness, hydrophobic/hydrophilic properties).
S. Gamri, A. Soric, Séverine Tomas, Bruno Molle, Nicolas Roche. Effects of pipe materials on biofouling under controlled hydrodynamic conditions. Journal of Water Reuse and Desalination, 2016, 6 (1), pp.167-174. ⟨10.2166/wrd.2015.037⟩. ⟨hal-01665987⟩
Rainier Hreiz, Nicolas Roche, Brahim Benyahia, M.A. Latifi. Multi-objective optimal control of small-size wastewater treatment plants. Chemical Engineering Research and Design, 2015, 102, pp.345 - 353. ⟨10.1016/j.cherd.2015.06.039⟩. ⟨hal-01665989⟩ Plus de détails...
In this work, a multi-objective dynamic optimization of the operating strategy of a small-size wastewater treatment plant is carried out. In-situ incineration of the excess sludge produced for electricity production is investigated in order to reduce the operating costs. The trade-offs between the treatment quality and the operating costs are characterized. Compared to the literature, emphasis is put on a more rigorous formulation of the problem and an accurate modeling of the underlying phenomena so as to get physically relevant solutions. Thus, from a mathematical perspective, the problem is formulated so that the solution is less sensitive to the - arbitrarily chosen-plant initial conditions. Modeling of physical phenomena e.g. the detrimental effect of the concentration of suspended solids in the mixed liquor, on oxygen transfer rate, has been included in the model. Several constraints are added to the problem so as to maintain the optimal solutions within the limits of validity of the mathematical model. The results provided a clear picture about the trade-offs between the treatment quality and the exploitation costs. Sludge incineration was shown to be of a high energetic profit, but it does not allow the plant to be electrically autonomous.
Rainier Hreiz, Nicolas Roche, Brahim Benyahia, M.A. Latifi. Multi-objective optimal control of small-size wastewater treatment plants. Chemical Engineering Research and Design, 2015, 102, pp.345 - 353. ⟨10.1016/j.cherd.2015.06.039⟩. ⟨hal-01665989⟩
A.-B. Hernandez, J.-H. Ferrasse, S. Akkache, Nicolas Roche. Thermochemical Conversion of Sewage Sludge by TGA-FTIR Analysis: Influence of Mineral Matter Added. Drying Technology, 2015, 33 (11), pp.1318-1326. ⟨10.1080/07373937.2015.1036283⟩. ⟨hal-01297640⟩ Plus de détails...
Thermal treatments, such as combustion, gasification, and pyrolysis, have been proven to be a convenient alternative to conventional sludge disposal technologies. Today, process development implies scaling up and so improving the reactor's design. In continuously operated reactors, fresh sewage sludge is in contact with solid residues (reacted material rich in mineral matter and char). Mineral matter has been reported to catalyze the thermo-chemical reactions involved but few works focus on this aspect. In this work, sewage sludge residues were added to fresh sewage sludge. Non-isothermal thermo-gravimetric analysis (TGA) coupled with infrared spectrometry (FTIR) showed that added residues reduce the characteristic reaction temperatures during char combustion and gasification (air, air-N2, and CO2 atmospheres). However, any considerable influence of residues was observed during pyrolysis experiments (N2 atmosphere). The analysis of gas produced during those experiments revealed further details about the solid decomposition, showing considerable differences between different atmospheres.
A.-B. Hernandez, J.-H. Ferrasse, S. Akkache, Nicolas Roche. Thermochemical Conversion of Sewage Sludge by TGA-FTIR Analysis: Influence of Mineral Matter Added. Drying Technology, 2015, 33 (11), pp.1318-1326. ⟨10.1080/07373937.2015.1036283⟩. ⟨hal-01297640⟩
Céline Bonnyaud, Didier Pradon, Raphael Zory, Djamel Bensmail, Nicolas Vuillerme, et al.. Gait parameters predicted by Timed Up and Go performance in stroke patients. NeuroRehabilitation, 2015, 36 (1), pp.73-80. ⟨10.3233/NRE-141194⟩. ⟨hal-02528987⟩ Plus de détails...
Céline Bonnyaud, Didier Pradon, Raphael Zory, Djamel Bensmail, Nicolas Vuillerme, et al.. Gait parameters predicted by Timed Up and Go performance in stroke patients. NeuroRehabilitation, 2015, 36 (1), pp.73-80. ⟨10.3233/NRE-141194⟩. ⟨hal-02528987⟩
Céline Bonnyaud, Didier Pradon, Raphael Zory, Djamel Bensmail, Nicolas Vuillerme, et al.. Does a Single Gait Training Session Performed Either Overground or on a Treadmill Induce Specific Short-Term Effects on Gait Parameters in Patients with Hemiparesis? A Randomized Controlled Study. Topics in Stroke Rehabilitation, 2015, 20 (6), pp.509-518. ⟨10.1310/tsr2006-509⟩. ⟨hal-02529024⟩ Plus de détails...
Céline Bonnyaud, Didier Pradon, Raphael Zory, Djamel Bensmail, Nicolas Vuillerme, et al.. Does a Single Gait Training Session Performed Either Overground or on a Treadmill Induce Specific Short-Term Effects on Gait Parameters in Patients with Hemiparesis? A Randomized Controlled Study. Topics in Stroke Rehabilitation, 2015, 20 (6), pp.509-518. ⟨10.1310/tsr2006-509⟩. ⟨hal-02529024⟩
Céline Bonnyaud, Raphael Zory, Johanna Robertson, Djamel Bensmail, Nicolas Vuillerme, et al.. Effect of an Overground Training Session Versus a Treadmill Training Session on Timed Up and Go in Hemiparetic Patients. Topics in Stroke Rehabilitation, 2015, 21 (6), pp.477-483. ⟨10.1310/tsr2106-477⟩. ⟨hal-02528990⟩ Plus de détails...
Céline Bonnyaud, Raphael Zory, Johanna Robertson, Djamel Bensmail, Nicolas Vuillerme, et al.. Effect of an Overground Training Session Versus a Treadmill Training Session on Timed Up and Go in Hemiparetic Patients. Topics in Stroke Rehabilitation, 2015, 21 (6), pp.477-483. ⟨10.1310/tsr2106-477⟩. ⟨hal-02528990⟩
Nicolas Roche, Bruno Molle. Recyclage et réutilisation des eaux industrielles et agricoles. R. MOSSERI, C. JEANDEL, A. EUZEN. Ouvrage l’eau à découvert, coordinateurs R, CNRS, 2015. ⟨hal-01313522⟩ Plus de détails...
Nicolas Roche, Bruno Molle. Recyclage et réutilisation des eaux industrielles et agricoles. R. MOSSERI, C. JEANDEL, A. EUZEN. Ouvrage l’eau à découvert, coordinateurs R, CNRS, 2015. ⟨hal-01313522⟩
Isabelle Seyssiecq, Mohsen Karrabi, Nicolas Roche. In situ rheological characterisation of wastewater sludge: Comparison of stirred bioreactor and pipe flow configurations. Chemical Engineering Journal, 2015, 259, pp.205 - 212. ⟨10.1016/j.cej.2014.07.102⟩. ⟨hal-01666306⟩ Plus de détails...
Andre Chanzy, Eric Sauquet, O. Banton, Nicolas Roche. Ressources hydriques en milieu méditerranéen. Provence-Alpes-Côte d’Azur, une région face au changement climatique, GREC-PACA, GREC-PACA, 40 p., 2015. ⟨hal-01603517⟩ Plus de détails...
Andre Chanzy, Eric Sauquet, O. Banton, Nicolas Roche. Ressources hydriques en milieu méditerranéen. Provence-Alpes-Côte d’Azur, une région face au changement climatique, GREC-PACA, GREC-PACA, 40 p., 2015. ⟨hal-01603517⟩
Martine Poux, Nicolas Roche. 10th European Congress of Chemical Engineering (ECCE10)/3rd European Congress of Applied Biotechnology (ECAB3)/5th European Process Intensification Conference (EPIC5) – Nice, France, September 27-October 1, 2015. Green Processing and Synthesis, 2015, 4 (2), pp.151-152. ⟨10.1515/gps-2015-0012⟩. ⟨hal-01898222⟩ Plus de détails...
1n September 2015, the city of Nice, France, will host the 10th European Congress of Chemical Engineering (ECCE10) in conjunction with the 3rd European Congress of Applied Biotechnology (ECAB3) and the 5th European Process Intensification Conference (EPIC5). This will be the most important scientific event in chemical and biochemical engineering in Europe in 2015. The global theme for this group of events is “Chemical and biochemical engineering for a new sustainable process industry in Europe”.
Martine Poux, Nicolas Roche. 10th European Congress of Chemical Engineering (ECCE10)/3rd European Congress of Applied Biotechnology (ECAB3)/5th European Process Intensification Conference (EPIC5) – Nice, France, September 27-October 1, 2015. Green Processing and Synthesis, 2015, 4 (2), pp.151-152. ⟨10.1515/gps-2015-0012⟩. ⟨hal-01898222⟩
Rainier Hreiz, M A Latifi, Nicolas Roche. Optimal design and operation of activated sludge processes: State-of-the-art. Chemical Engineering Journal, 2015, 281, pp.900 - 920. ⟨10.1016/j.cej.2015.06.125⟩. ⟨hal-01458423⟩ Plus de détails...
The activated sludge process (ASP) is the most commonly used process for wastewater treatment. Improving its performance is necessary from economic and environmental point of views. In this context, dynamic optimization is a powerful tool for assisting engineers in determining optimal operations and designs for ASPs. However, the real optimality of the solution strongly depends on the optimization problem statement, for which unfortunately, there is no standard or commonly accepted formulation. In a hopeful attempt to provide a guideline for future works on the topic, this paper reviews the literature devoted to optimal control and design of ASPs. The main issues to be addressed in order to get reliable solutions are discussed , among which: (1) Managing the inevitable mismatch between the model predictions and the real ASP operation. (2) Dealing with the unpredictable variations in the wastewater characteristics. (3) Accounting for the slowest dynamic processes occurring in ASPs. (4) Appropriately selecting the decision variables and the flowsheet structure in order to simplify the problem formulation from a mathematical perspective. (5) Conveniently choosing the cost functions expressions/correlations. (6) Successfully selecting the mathematical constraints in order to guarantee physically relevant operations.
Rainier Hreiz, M A Latifi, Nicolas Roche. Optimal design and operation of activated sludge processes: State-of-the-art. Chemical Engineering Journal, 2015, 281, pp.900 - 920. ⟨10.1016/j.cej.2015.06.125⟩. ⟨hal-01458423⟩
Isabelle Seyssiecq, Mohsen Karrabi, Nicolas Roche. In situ rheological characterisation of wastewater sludge: comparison of stirred bioreactor and pipe flow configurations. The Chemical Engineering Journal, 2015, 259, pp.205-212. ⟨10.1016/j.cej.2014.07.102⟩. ⟨hal-01467179⟩ Plus de détails...
In the present work, non-Newtonian properties of activated sludge are investigated using a bench test device specially developed for the purpose of this work. This set-up consists in a bioreactor equipped with a helical ribbon impeller (HRI configuration), and a recirculation loop of the sludge (pipe flow (PF) configuration). The HRI configuration is equipped with a motor and a torque-meter allowing in situ determination of sludge rheogram under stirred reactor conditions. On the PF configuration, differential pressure and flow transducers are implemented, allowing in situ determination of sludge rheogram under piping conditions. Both configurations are then compared. The yield stress, flow and consistency indexes of sludge suspensions (Herschel–Bulkley rheological law coefficients, $\tau_y$, $K$ and $n$) are determined over a large range of total suspended solid (TSS) concentrations, (12–38 g L$^{−1}$) in the laminar flow regime. The analysis of experimental data shows that measurements performed with the PF configuration have to be corrected in order to take into account a wall slip phenomenon. A correction model is proposed that shows that slip mechanism is mostly due to wall static depletion at low solid concentrations (12–17 g L$^{−1}$), then turns to shear induced migration effect at higher solid concentrations (26–38 g L$^{−1}$).
Isabelle Seyssiecq, Mohsen Karrabi, Nicolas Roche. In situ rheological characterisation of wastewater sludge: comparison of stirred bioreactor and pipe flow configurations. The Chemical Engineering Journal, 2015, 259, pp.205-212. ⟨10.1016/j.cej.2014.07.102⟩. ⟨hal-01467179⟩
Jean Slawinski, Didier Pradon, Djamel Bensmail, Nicolas Roche, Raphaël Zory. Energy Cost of Obstacle Crossing in Stroke Patients. American Journal of Physical Medicine and Rehabilitation, 2014, 93 (12), pp.1044--1050. ⟨10.1097/PHM.0000000000000122⟩. ⟨hal-01467715⟩ Plus de détails...
OBJECTIVE: The purpose of this study was to analyze the effects of clearing and skirting obstacles during the gait on the energetic cost of walking (ECW) of patients with chronic hemiplegia. The hypothesis was that hemiplegia would have a greatest increase in the ECW than in the healthy group. DESIGN: Fifteen healthy subjects and 17 patients with chronic hemiplegia completed two 6-min walking sessions: one with obstacles and the other without obstacles. During both sessions, the patients were equipped with a portable gas analyzer to measure oxygen uptake (V˙o2). Gait velocity and ECW were calculated. RESULTS: In both groups, gait velocity was lower in the with-obstacles condition and the ECW was significantly higher. V˙o2 was greater in the with-obstacles condition for the healthy group, whereas it remained unchanged for the group with hemiplegia. CONCLUSIONS: Results demonstrated that the addition of obstacles during gait increased the ECW and decreased mean walking speed in both the healthy subjects and the patients with hemiplegia. More interestingly, the authors found differences in adaptation strategies between the healthy subjects and the patients with hemiplegia. During the with-obstacles condition, the oxygen uptakes of the healthy subjects increased and mean walking speed decreased, whereas, in the subjects with hemiplegia, only mean walking speed decreased. CONCLUSIONS: Results demonstrated that the addition of obstacles during gait increased the ECW and decreased mean walking speed in both the healthy subjects and the patients with hemiplegia. More interestingly, the authors found differences in adaptation strategies between the healthy subjects and the patients with hemiplegia. During the with-obstacles condition, the oxygen uptakes of the healthy subjects increased and mean walking speed decreased, whereas, in the subjects with hemiplegia, only mean walking speed decreased.
Jean Slawinski, Didier Pradon, Djamel Bensmail, Nicolas Roche, Raphaël Zory. Energy Cost of Obstacle Crossing in Stroke Patients. American Journal of Physical Medicine and Rehabilitation, 2014, 93 (12), pp.1044--1050. ⟨10.1097/PHM.0000000000000122⟩. ⟨hal-01467715⟩
Journal: American Journal of Physical Medicine and Rehabilitation
Ming Zeng, Audrey Soric, Nicolas Roche. Modeling partial nitrification and denitrification in a hybrid biofilm reactor: calibration by retention time distribution and respirometric tests. Environmental Science and Pollution Research, 2014, 22 (17), pp.nicolas.roche. ⟨10.1007/s11356-014-3667-0⟩. ⟨hal-01086582⟩ Plus de détails...
In this study, partial nitrification coupled with denitrification is modeled in a hybrid biofilm reactor with different hydraulic saturation conditions. The activated sludge model with two-steps nitrification is implemented in GPS-X software. Hydrodynamic modeling by retention time distribution (RTD) analysis and biokinetic measurement by respirometric tests are two significant parts of model calibration. By combining these two parts, partial nitrification in the aerobic part of the column is well simulated with a good agreement between experimental and modeled effluent concentrations of NH4+ and NO2-. Particularly, fully hydraulic saturation condition contributes to the large hydraulic volume of 1.9 L and high produced NO2- concentration around 40 mg.L-1. However, modeling denitrification still needs to be improved with more calibrated parameters. Furthermore, three alternatives are proposed for the optimization of reactor design and operation
Ming Zeng, Audrey Soric, Nicolas Roche. Modeling partial nitrification and denitrification in a hybrid biofilm reactor: calibration by retention time distribution and respirometric tests. Environmental Science and Pollution Research, 2014, 22 (17), pp.nicolas.roche. ⟨10.1007/s11356-014-3667-0⟩. ⟨hal-01086582⟩
Journal: Environmental Science and Pollution Research
Lauren E. Barton, Melanie Auffan, Marie Bertrand-Huleux, mohamed Barakat, Catherine Santaella, et al.. The Transformation of Pristine and Citrate-Functionalized CeO2 Nanoparticles in a Laboratory Scale Aerobic Activated Sludge Reactor. Environmental Science and Technology, 2014, 48 (13), pp.7289 - 7296. ⟨10.1021/es404946y⟩. ⟨hal-01086566⟩ Plus de détails...
Engineered nanomaterials (ENMs) are used to enhance the properties of many manufactured products and technologies. Increased use of ENMs will inevitably lead to their release into the environment. An important route of exposure is through the waste stream, where ENMs will enter wastewater treatment plants (WWTPs), undergo transformations, and be discharged with treated effluent or biosolids. To better understand the fate of a common ENM in WWTPs, experiments with laboratory-scale activated sludge reactors and pristine and citrate-functionalized CeO2 nanoparticles (NPs) were conducted. Greater than 90% of the CeO2 introduced was observed to associate with biosolids. This association was accompanied by reduction of the Ce(IV) NPs to Ce(III). After 5 weeks in the reactor, 44 ± 4% reduction was observed for the pristine NPs and 31 ± 3% for the citrate-functionalized NPs, illustrating surface functionality dependence. Thermodynamic arguments suggest that the likely Ce(III) phase generated would be Ce2S3. This study indicates that the majority of CeO2 NPs (>90% by mass) entering WWTPs will be associated with the solid phase, and a significant portion will be present as Ce(III). At maximum, 10% of the CeO2 will remain in the effluent and be discharged as a Ce(IV) phase, governed by cerianite (CeO2).
Lauren E. Barton, Melanie Auffan, Marie Bertrand-Huleux, mohamed Barakat, Catherine Santaella, et al.. The Transformation of Pristine and Citrate-Functionalized CeO2 Nanoparticles in a Laboratory Scale Aerobic Activated Sludge Reactor. Environmental Science and Technology, 2014, 48 (13), pp.7289 - 7296. ⟨10.1021/es404946y⟩. ⟨hal-01086566⟩
Julien Boudarham, Nicolas Roche, Didier Pradon, Eric Delouf, Djamel Bensmail, et al.. Effects of Quadriceps Muscle Fatigue on Stiff-Knee Gait in Patients with Hemiparesis. PLoS ONE, 2014, 9 (4), pp.e94138. ⟨10.1371/journal.pone.0094138⟩. ⟨hal-02529007⟩ Plus de détails...
The relationship between neuromuscular fatigue and locomotion has never been investigated in hemiparetic patients despite the fact that, in the clinical context, patients report to be more spastic or stiffer after walking a long distance or after a rehabilitation session. The aim of this study was to evaluate the effects of quadriceps muscle fatigue on the biomechanical gait parameters of patients with a stiff-knee gait (SKG). Thirteen patients and eleven healthy controls performed one gait analysis before a protocol of isokinetic quadriceps fatigue and two after (immediately after and after 10 minutes of rest). Spatiotemporal parameters, sagittal knee and hip kinematics, rectus femoris (RF) and vastus lateralis (VL) kinematics and electromyographic (EMG) activity were analyzed. The results showed that quadriceps muscle weakness, produced by repetitive concentric contractions of the knee extensors, induced an improvement of spatiotemporal parameters for patients and healthy subjects. For the patient group, the increase in gait velocity and step length was associated with i) an increase of sagittal hip and knee flexion during the swing phase, ii) an increase of the maximal normalized length of the RF and VL and of the maximal VL lengthening velocity during the pre-swing and swing phases, and iii) a decrease in EMG activity of the RF muscle during the initial pre-swing phase and during the latter 2/3 of the initial swing phase. These results suggest that quadriceps fatigue did not alter the gait of patients with hemiparesis walking with a SKG and that neuromuscular fatigue may play the same functional role as an anti-spastic treatment such as botulinum toxin-A injection. Strength training of knee extensors, although commonly performed in rehabilitation, does not seem to be a priority to improve gait of these patients.
Julien Boudarham, Nicolas Roche, Didier Pradon, Eric Delouf, Djamel Bensmail, et al.. Effects of Quadriceps Muscle Fatigue on Stiff-Knee Gait in Patients with Hemiparesis. PLoS ONE, 2014, 9 (4), pp.e94138. ⟨10.1371/journal.pone.0094138⟩. ⟨hal-02529007⟩
Julien Boudarham, Nicolas Roche, Mickael Teixeira, Sophie Hameau, Johanna Robertson, et al.. Relationship between neuromuscular fatigue and spasticity in chronic stroke patients: A pilot study. Journal of Electromyography and Kinesiology, 2014, 24 (2), pp.292-299. ⟨10.1016/j.jelekin.2013.11.006⟩. ⟨hal-02529022⟩ Plus de détails...
Julien Boudarham, Nicolas Roche, Mickael Teixeira, Sophie Hameau, Johanna Robertson, et al.. Relationship between neuromuscular fatigue and spasticity in chronic stroke patients: A pilot study. Journal of Electromyography and Kinesiology, 2014, 24 (2), pp.292-299. ⟨10.1016/j.jelekin.2013.11.006⟩. ⟨hal-02529022⟩
Journal: Journal of Electromyography and Kinesiology
Claire Marchiori, Nicolas Roche, Nicolas Vuillerme, Raphael Zory, Didier Pradon. Effect of multisite botulinum toxin injections on gait quality in adults with cerebral palsy. Disability and Rehabilitation, 2014, 36 (23), pp.1971-1974. ⟨10.3109/09638288.2014.883443⟩. ⟨hal-02529012⟩ Plus de détails...
In the management of adults with cerebral palsy (CP), one of the goals is to monitor and prevent spasticity-related deteriorations in gait. Botulinum Toxin Injections (BTI) are commonly used to treat this spasticity in these patients. The purpose of this study was to evaluate (i) the effect of multi-site BTI on gait patterns in adults with CP and (ii) to determine if these modifications could be detected by the Gait Deviation Index (GDI).
Claire Marchiori, Nicolas Roche, Nicolas Vuillerme, Raphael Zory, Didier Pradon. Effect of multisite botulinum toxin injections on gait quality in adults with cerebral palsy. Disability and Rehabilitation, 2014, 36 (23), pp.1971-1974. ⟨10.3109/09638288.2014.883443⟩. ⟨hal-02529012⟩
Souha Gamri, Audrey Soric, Séverine Tomas, Bruno Molle, Nicolas Roche. Biofilm development in micro-irrigation emitters for wastewater reuse. Irrigation Science, 2014, 32 (1), pp.77-85. ⟨10.1007/s00271-013-0414-0⟩. ⟨hal-00992245⟩ Plus de détails...
Laboratory experiments were carried out to investigate bioclogging on three types of online emitters using synthetic wastewater filtered at 10 μm (COD = 200 mg/L). The three types of emitters were as follows: non-pressure-compensating emitters delivering 2 L/h (NPC2), non-pressure-compensating emitters delivering 4 L/h (NPC4) and pressure-compensating emitters delivering 2.2 L/h (PC). They were plugged on two parallel pipe diameters (16 and 20 mm). Emitter performance was followed by flow rate measurements. The results showed that PC emitters seemed to be more sensitive to clogging than NPC emitters. Biofilm was observed mainly on NPC flow paths and PC membranes; its presence was also confirmed by the assessment of different water quality parameters such as total organic carbon and pH. Experimental results compared with a model designed with computational fluid dynamics Software (ANSYS Fluent®) showed relations between biofilm development and velocity distribution on NPC flow paths. Finally, pipe diameter also appeared to be a parameter inducing emitter clogging.
Souha Gamri, Audrey Soric, Séverine Tomas, Bruno Molle, Nicolas Roche. Biofilm development in micro-irrigation emitters for wastewater reuse. Irrigation Science, 2014, 32 (1), pp.77-85. ⟨10.1007/s00271-013-0414-0⟩. ⟨hal-00992245⟩
Céline Bonnyaud, Raphael Zory, Julien Boudarham, Didier Pradon, Djamel Bensmail, et al.. Effect of a robotic restraint gait training versus robotic conventional gait training on gait parameters in stroke patients. Experimental Brain Research, 2014, 232 (1), pp.31-42. ⟨10.1007/s00221-013-3717-8⟩. ⟨hal-02529025⟩ Plus de détails...
Céline Bonnyaud, Raphael Zory, Julien Boudarham, Didier Pradon, Djamel Bensmail, et al.. Effect of a robotic restraint gait training versus robotic conventional gait training on gait parameters in stroke patients. Experimental Brain Research, 2014, 232 (1), pp.31-42. ⟨10.1007/s00221-013-3717-8⟩. ⟨hal-02529025⟩
Nicolas Roche, Didier Pradon, Julie Cosson, Johanna Robertson, Claire Marchiori, et al.. Categorization of gait patterns in adults with cerebral palsy: A clustering approach. Gait & Posture, 2014, 39 (1), pp.235-240. ⟨10.1016/j.gaitpost.2013.07.110⟩. ⟨hal-02529032⟩ Plus de détails...
Nicolas Roche, Didier Pradon, Julie Cosson, Johanna Robertson, Claire Marchiori, et al.. Categorization of gait patterns in adults with cerebral palsy: A clustering approach. Gait & Posture, 2014, 39 (1), pp.235-240. ⟨10.1016/j.gaitpost.2013.07.110⟩. ⟨hal-02529032⟩
A. Hernandez, J.-H. Ferrasse, Nicolas Roche. Limiting the Pollutant Content in the Sewage Sludge Producer Gas through Staged Gasification. Chemical Engineering and Technology, 2013, 36 (11), pp.1985 - 1996. ⟨10.1002/ceat.201300103⟩. ⟨hal-01666322⟩ Plus de détails...
A. Hernandez, J.-H. Ferrasse, Nicolas Roche. Limiting the Pollutant Content in the Sewage Sludge Producer Gas through Staged Gasification. Chemical Engineering and Technology, 2013, 36 (11), pp.1985 - 1996. ⟨10.1002/ceat.201300103⟩. ⟨hal-01666322⟩
S. Akkache, I. Seyssiecq, Nicolas Roche. Effect of exo-polysaccharide concentration in the rheological properties and settling ability of activated sludge. Environmental Technology, 2013, 34 (22), pp.2995 - 3003. ⟨10.1080/09593330.2013.798001⟩. ⟨hal-01666325⟩ Plus de détails...
S. Akkache, I. Seyssiecq, Nicolas Roche. Effect of exo-polysaccharide concentration in the rheological properties and settling ability of activated sludge. Environmental Technology, 2013, 34 (22), pp.2995 - 3003. ⟨10.1080/09593330.2013.798001⟩. ⟨hal-01666325⟩
Céline Bonnyaud, Raphael Zory, Didier Pradon, Nicolas Vuillerme, Nicolas Roche. Clinical and biomechanical factors which predict Timed Up and Down Stairs test performance in hemiparetic patients. Gait & Posture, 2013, 38 (3), pp.466-470. ⟨10.1016/j.gaitpost.2013.01.015⟩. ⟨hal-02529045⟩ Plus de détails...
Céline Bonnyaud, Raphael Zory, Didier Pradon, Nicolas Vuillerme, Nicolas Roche. Clinical and biomechanical factors which predict Timed Up and Down Stairs test performance in hemiparetic patients. Gait & Posture, 2013, 38 (3), pp.466-470. ⟨10.1016/j.gaitpost.2013.01.015⟩. ⟨hal-02529045⟩
Julien Boudarham, Nicolas Roche, Didier Pradon, Céline Bonnyaud, Djamel Bensmail, et al.. Variations in Kinematics during Clinical Gait Analysis in Stroke Patients. PLoS ONE, 2013, 8 (6), pp.e66421. ⟨10.1371/journal.pone.0066421⟩. ⟨hal-02529041⟩ Plus de détails...
In addition to changes in spatio-temporal and kinematic parameters, patients with stroke exhibit fear of falling as well as fatigability during gait. These changes could compromise interpretation of data from gait analysis. The aim of this study was to determine if the gait of hemiplegic patients changes significantly over successive gait trials. Forty two stroke patients and twenty healthy subjects performed 9 gait trials during a gait analysis session. The mean and variability of spatio-temporal and kinematic joint parameters were analyzed during 3 groups of consecutive gait trials (1-3, 4-6 and 7-9). Principal component analysis was used to reduce the number of variables from the joint kinematic waveforms and to identify the parts of the gait cycle which changed during the gait analysis session. The results showed that i) spontaneous gait velocity and the other spatio-temporal parameters significantly increased, and ii) gait variability decreased, over the last 6 gait trials compared to the first 3, for hemiplegic patients but not healthy subjects. Principal component analysis revealed changes in the sagittal waveforms of the hip, knee and ankle for hemiplegic patients after the first 3 gait trials. These results suggest that at the beginning of the gait analysis session, stroke patients exhibited phase of adaptation,characterized by a ''cautious gait'' but no fatigue was observed.
Julien Boudarham, Nicolas Roche, Didier Pradon, Céline Bonnyaud, Djamel Bensmail, et al.. Variations in Kinematics during Clinical Gait Analysis in Stroke Patients. PLoS ONE, 2013, 8 (6), pp.e66421. ⟨10.1371/journal.pone.0066421⟩. ⟨hal-02529041⟩
Kamel S Zerari, Isabelle Seyssieq, Djamal-Eddine Akretche, Nicolas Roche. Enhancement of oxygen mass transfer coefficients in a hybrid membrane bioreactor. Journal of Chemical Technology and Biotechnology, 2013, 88 (6), pp.1007 - 1013. ⟨10.1002/jctb.4062⟩. ⟨hal-01666331⟩ Plus de détails...
Kamel S Zerari, Isabelle Seyssieq, Djamal-Eddine Akretche, Nicolas Roche. Enhancement of oxygen mass transfer coefficients in a hybrid membrane bioreactor. Journal of Chemical Technology and Biotechnology, 2013, 88 (6), pp.1007 - 1013. ⟨10.1002/jctb.4062⟩. ⟨hal-01666331⟩
Journal: Journal of Chemical Technology and Biotechnology
Ana Belén Hernandez, Jean-Henry Ferrasse, Nicolas Roche. Limiting the pollutant content in the sewage sludge producer gas through staged gasification. Chemical Engineering and Technology, 2013, 36 (11), pp.1985-1996. ⟨10.1002/ceat.201300103⟩. ⟨hal-00978823⟩ Plus de détails...
Sewage sludge gasification deals with the release of nitrogen and sulfur compounds, the main sources for pollutants during the final combustion. In order to handle these compounds, a staged gasification process is proposed. During the low-temperature thermal treatment of the first stage, nitrogen and sulfur compounds are removed from the solid fuel. The second stage converts the remaining solid into combustible compounds through gasification reactions. The producer gas obtained during this stage is compared to the producer gas of a simple gasification. The presence of pollutant precursors was considerably diminished during the staged experiments. A successful staged gasification may eliminate the need for downstream cleanup and thus limit the energy consumption. This work proves that staged gasification may be the key to obtain energy from waste fuel, limiting the concerns about pollutants.
Ana Belén Hernandez, Jean-Henry Ferrasse, Nicolas Roche. Limiting the pollutant content in the sewage sludge producer gas through staged gasification. Chemical Engineering and Technology, 2013, 36 (11), pp.1985-1996. ⟨10.1002/ceat.201300103⟩. ⟨hal-00978823⟩
Ming Zeng, Audrey Soric, Nicolas Roche. Calibration of hydrodynamic behavior and biokinetics for TOC removal modeling in biofilm reactors under different hydraulic conditions. Bioresource Technology, 2013, 144, pp.202-209. ⟨10.1016/j.biortech.2013.06.111⟩. ⟨hal-00978831⟩ Plus de détails...
In this study, total organic carbon (TOC) biodegradation was simulated by GPS-X software in biofilm reactors with carriers of plastic rings and glass beads under different hydraulic conditions. Hydrodynamic model by retention time distribution and biokinetic measurement by in-situ batch test served as two significant parts of model calibration. Experimental results showed that TOC removal efficiency was stable in both media due to the enough height of column, although the actual hydraulic volume changed during the variation of hydraulic condition. Simulated TOC removal efficiencies were close to experimental ones with low theil inequality coefficient values (below 0.15). Compared with glass beads, more TOC was removed in the filter with plastic rings due to the larger actual hydraulic volume and lower half saturation coefficient in spite of its lower maximum specific growth rate of biofilm, which highlighted the importance of calibrating hydrodynamic behavior and biokinetics.
Ming Zeng, Audrey Soric, Nicolas Roche. Calibration of hydrodynamic behavior and biokinetics for TOC removal modeling in biofilm reactors under different hydraulic conditions. Bioresource Technology, 2013, 144, pp.202-209. ⟨10.1016/j.biortech.2013.06.111⟩. ⟨hal-00978831⟩
S. Akkache, Isabelle Seyssiecq, Nicolas Roche. Effect of exo-polysaccharide concentration in the rheological properties and settling ability of activated sludge. Environmental Technology, 2013, 34 (22), pp.2995-3003. ⟨10.1080/09593330.2013.798001⟩. ⟨hal-00968262⟩ Plus de détails...
The non-Newtonian properties of activated sludge (AS) suspension lead to transfer limitations (oxygen, substrate...) and operation difficulties in Waste Water Treatment Plants (WWTP). The current approach involves assuming the sludge behaves like water on a rheological point of view, and then oversizing pumping and aeration devices, which represent over 60% of the operating cost in WWTP. The objective of this work is to understand the effect of bioflocculation on the rheological properties and the settling ability of AS suspensions, by means of variations in concentration of exo-cellular polysaccharides. Experiments have been conducted in a 20 L laboratory scale bioreactor at a constant retention time of 20 days and with a total suspended solid concentration between 15 and 20 g L−1.
S. Akkache, Isabelle Seyssiecq, Nicolas Roche. Effect of exo-polysaccharide concentration in the rheological properties and settling ability of activated sludge. Environmental Technology, 2013, 34 (22), pp.2995-3003. ⟨10.1080/09593330.2013.798001⟩. ⟨hal-00968262⟩
Ming Zeng, Audrey Soric, Jean-Henry Ferrasse, Nicolas Roche. Interpreting hydrodynamic behaviour by the model of stirred tanks in series with exchanged zones: preliminary study in lab-scale trickling filters. Environmental Technology, 2013, 34 (18), pp.2571-2578. ⟨10.1080/09593330.2013.781199⟩. ⟨hal-00978807⟩ Plus de détails...
In trickling filters for wastewater treatment, hydrodynamic behaviour is affected by the growth of biofilm on the porous medium. Therefore, modelling hydrodynamic behaviour is necessary and efficient to predict the biodegradation of pollutants. In this study, laboratory-scale trickling filters were filled with two different porous media (glass beads and plastic rings) and were fed by a synthetic substrate in batch mode. Total organic carbon (TOC) of the effluent was measured and retention time distribution (RTD) was determined by injecting NaCl. Results showed that medium had no significant effect on TOC removal rate (around 80% and 60% respectively for batch time of seven and two days). However, regarding the hydrodynamic behaviour, the effective volume ratio and hydraulic efficiency in the glass beads bed increased remarkably from 28% and 18% to 80% and 70%, respectively, with the reduction of dispersion coefficient (from 4.55 to 1.53). Moreover, the short batch time accelerated this change. Conversely, no variation of hydrodynamic behaviour in plastic rings bed was evident. Along with the feeding of synthetic substrate, biofilm concentration ranged from 1.5 to 10.1 g/L in the glass beads reactor and it achieved around 2.8 g/L in the plastic rings reactor. Hydrodynamic modelling indicated that the model of stirred tanks in series with exchanged zones fitted the experimental results well. These gave values of mobile and immobile volumes of 51 mL and 17 mL, respectively, in the glass beads filter and 25 mL and 15 mL, respectively, in the plastic rings filter.
Ming Zeng, Audrey Soric, Jean-Henry Ferrasse, Nicolas Roche. Interpreting hydrodynamic behaviour by the model of stirred tanks in series with exchanged zones: preliminary study in lab-scale trickling filters. Environmental Technology, 2013, 34 (18), pp.2571-2578. ⟨10.1080/09593330.2013.781199⟩. ⟨hal-00978807⟩
Kamel Zerari, Isabelle Seyssiecq, Djamal-Eddine Akretche, Nicolas Roche. Enhancement of oxygen mass transfer coefficients in a Membrane Immersed Hybrid Bioreactor. Journal of Chemical Technology and Biotechnology, 2013, 88 (6), pp.1007-1013. ⟨10.1002/jctb.4062⟩. ⟨hal-00968246⟩ Plus de détails...
Oxygen mass transfer is a key parameter for processing aerobic bioreactors in terms of operational costs and efficiency. In membrane bioreactors, a reduction of the aeration capacity is often observed at high solid ratios, caused by the presence of solids and the non-Newtonian properties of activated sludge.
Kamel Zerari, Isabelle Seyssiecq, Djamal-Eddine Akretche, Nicolas Roche. Enhancement of oxygen mass transfer coefficients in a Membrane Immersed Hybrid Bioreactor. Journal of Chemical Technology and Biotechnology, 2013, 88 (6), pp.1007-1013. ⟨10.1002/jctb.4062⟩. ⟨hal-00968246⟩
Journal: Journal of Chemical Technology and Biotechnology
A. B. Hernandez, Jean-Henry Ferrasse, Perrine Chaurand, Hans Saveyn, Daniel Borschneck, et al.. Mineralogy and leachability of gasified sewage sludge solid residues. Journal of Hazardous Materials, 2011, 191 (1-3), pp.219-227. ⟨10.1016/j.jhazmat.2011.04.070⟩. ⟨hal-00766629⟩ Plus de détails...
Gasification of sewage sludge produces combustible gases as well as tar and a solid residue as by-products. This must be taken into account when determining the optimal thermal conditions for the gasification process. In this study, the influence of temperature, heating atmosphere and residence time on the characteristics of the gasified sewage sludge residues is investigated. ICP-AES analyses reveal that the major chemical elements in the char residues are phosphorus, calcium, iron and silicon. Heavy metals such as copper, zinc, chromium, nickel and lead are also present at relatively high levels - from 50 to more than 1000 mg/kg of dry matter. The major mineral phases' identification - before and after heating as well as their morphology and approximate chemistry (XRD and SEM-EDX) demonstrate that a number of transformations take place during gasification. These are influenced by the reactor's temperature and the oxidative degree of its internal atmosphere. The copper-, zinc- and chromium-bearing phases are studied using chemometric tools, showing that the distribution of those metals among the mineral phases is considerably different. Finally, batch-leaching tests reveal that metals retained in the residue are significantly stabilized after thermal treatment to a higher or lower extent, depending on the thermal conditions applied.
A. B. Hernandez, Jean-Henry Ferrasse, Perrine Chaurand, Hans Saveyn, Daniel Borschneck, et al.. Mineralogy and leachability of gasified sewage sludge solid residues. Journal of Hazardous Materials, 2011, 191 (1-3), pp.219-227. ⟨10.1016/j.jhazmat.2011.04.070⟩. ⟨hal-00766629⟩
Audrey Soric, Jean-Henry Ferrasse, Nicolas Roche. Microcalorimetric qualitative analysis of biofilm development in porous media used in wastewater treatment by constructed wetland. Journal of Thermal Analysis and Calorimetry, 2011, 104 (1), pp.113-118. ⟨10.1007/s10973-010-1252-4⟩. ⟨hal-01197444⟩ Plus de détails...
Audrey Soric, Jean-Henry Ferrasse, Nicolas Roche. Microcalorimetric qualitative analysis of biofilm development in porous media used in wastewater treatment by constructed wetland. Journal of Thermal Analysis and Calorimetry, 2011, 104 (1), pp.113-118. ⟨10.1007/s10973-010-1252-4⟩. ⟨hal-01197444⟩
Journal: Journal of Thermal Analysis and Calorimetry
L. Clouzot, Nicolas Roche, B. Marrot. Effect of membrane bioreactor configurations on sludge structure and microbial activity. Bioresource Technology, 2011, 102 (2), pp.975-981. ⟨10.1016/j.biortech.2010.09.058⟩. ⟨hal-01292667⟩ Plus de détails...
The aim of this paper was to determine the effect of two different membrane bioreactor (MBR) configurations (external/immersed) on sludge structure and microbial activity. Sludge structure was deduced from rheological measurements. The high shear stress induced by the recirculation pump in the external MBR was shown to result in decreasing viscosity due to activated sludge (AS) deflocculation. Besides, soluble microbial products (SMP) release was higher in the external MBR (5 mgCOD gMLVSS−1) than in the immersed configuration (2 mgCOD gMLVSS−1). Microbial activity was followed from respirometry tests by focusing on the distinction between heterotrophs and autotrophs. An easier autotrophic microbe development was then observed in the immersed MBR compared to the external one. However, the external MBR was shown to allow better heterotrophic microbe development.
L. Clouzot, Nicolas Roche, B. Marrot. Effect of membrane bioreactor configurations on sludge structure and microbial activity. Bioresource Technology, 2011, 102 (2), pp.975-981. ⟨10.1016/j.biortech.2010.09.058⟩. ⟨hal-01292667⟩
Hans Saveyn, J.H. Ferrasse, A. B. Hernandez, J. Rose, Paul van Der Meeren, et al.. The Distribution of Heavy Metals Following Sewage Sludge Gasification
. Journal of Residuals Science and Technology, 2011, 8 (2), pp.61-66. ⟨hal-01300386⟩ Plus de détails...
Limited knowledge exists about the fate of inorganic components, and especially metallic species, present in sewage sludge, upon gasification. This study shows that major elements are mainly retained within the sludge char, whereas minor elements such as Cd, Pb, Zn, As and Hg are partially or completely lost due to volatilization or melting from the sludge matrix. Hence, this work stresses the importance of monitoring the metal distribution during the gasification process.
Hans Saveyn, J.H. Ferrasse, A. B. Hernandez, J. Rose, Paul van Der Meeren, et al.. The Distribution of Heavy Metals Following Sewage Sludge Gasification
. Journal of Residuals Science and Technology, 2011, 8 (2), pp.61-66. ⟨hal-01300386⟩
Journal: Journal of Residuals Science and Technology
Jean-Henry Ferrasse, C. Dumas, Nicolas Roche. Experimental results and model for N-gas compound production in pure steam gasification for wastewater sewage sludge. Chemical Engineering and Technology, 2011, 34 (1), pp.103-110. ⟨10.1002/ceat.201000328⟩. ⟨hal-01025265⟩ Plus de détails...
Sewage sludge produced in wastewater treatment plants represent a significant portion of waste resulting from human activity and it is important to offer new ways of treatment. Thermal gasification of sludge is a promising thermal treatment, particularly because it can lead to a recovery of energy and a drastic reduction in the initial waste volume. However, it is a subject that has rarely been treated in the literature for sewage sludge. In particular, the nitrogen compounds present in significant quantities in the sewage sludge and their reactions during a thermal gasification step, must necessarily be taken into account. In order to study nitrogen behavior, this paper presents experimental results that are included in a model to predict NH3 emission.
Jean-Henry Ferrasse, C. Dumas, Nicolas Roche. Experimental results and model for N-gas compound production in pure steam gasification for wastewater sewage sludge. Chemical Engineering and Technology, 2011, 34 (1), pp.103-110. ⟨10.1002/ceat.201000328⟩. ⟨hal-01025265⟩
E. Barbot, I. Seyssiecq, Nicolas Roche, B. Marrot. Inhibition of activated sludge respiration by sodium azide addition: Effect on rheology and oxygen transfer. Journal Chemical Engineering, 2010, 163 (3), pp.230-235. ⟨10.1016/j.cej.2010.07.050⟩. ⟨hal-01297615⟩ Plus de détails...
Although microorganism respiration inhibition by sodium azide (NaN3) is used in some studies to identify activated sludge adsorption capacity, little is known about the effect of this compound on the suspension properties. In this study we have investigated the effect of NaN3 addition on both volumetric oxygen mass transfer coefficient and rheology of activated sludge (AS) suspensions in a 1.9 L bioreactor. The rheological properties (shear thinning one) of AS suspensions with and without NaN3 addition are measured in situ (triphasic conditions). It appears that NaN3 addition leads to a deflocculation of AS suspensions and thus a decrease in apparent viscosity. A small amount of suspended solids was added in order to obtain identical apparent viscosities (under 1.2 or 46.3 s−1) for AS suspensions with and without NaN3 addition. KLa values were then measured in both respiring and non-respiring suspensions for different air flow rates (2, 3 or 4 L/min) and under low or high mechanical shear rate (1.2 or 46.3 s−1). Results show that under high mechanical shear rate, the respiration state for a given air flow rate does not impact the KLa values. On the contrary, under low mechanical shear rate, NaN3 addition induces an increase of KLa values in comparison with those obtained with the respiring biomass. This effect, for a same apparent viscosity, is attributed to the deflocculation observed in the presence of NaN3. Indeed, AS with and without NaN3 addition used for the KLa measurements induce a modification of the floc internal structure, corresponding to smaller floc size in the case of NaN3 addition.
E. Barbot, I. Seyssiecq, Nicolas Roche, B. Marrot. Inhibition of activated sludge respiration by sodium azide addition: Effect on rheology and oxygen transfer. Journal Chemical Engineering, 2010, 163 (3), pp.230-235. ⟨10.1016/j.cej.2010.07.050⟩. ⟨hal-01297615⟩
Ludiwine Clouzot, Pierre Doumenq, Nicolas Roche, Benoît Marrot. Kinetic parameters for 17α-ethinylestradiol removal by nitrifying activated sludge developed in a membrane bioreactor. Bioresource Technology, 2010, 101 (16), pp.6425-6431. ⟨10.1016/j.biortech.2010.03.039⟩. ⟨hal-01024728⟩ Plus de détails...
The synthetic hormone 17α-ethinylestradiol (EE2) is primarily removed in wastewater treatment plants (WWTPs) by sorption, and nitrifying biomass has been shown to be responsible for EE2 biodegradation. Membrane bioreactor (MBR) technology was chosen to develop a community of autotrophic, nitrifying micro-organisms and determine kinetic parameters for EE2 biodegradation. Biological inhibition by azide was applied to differentiate sorption from biodegradation. Activated sludge (AS) was acclimated in the MBR to a substrate specific to autotrophic biomass and resulted in an increase in nitrifying activity. Acclimated AS was used to successfully biodegrade EE2 (11% increase in EE2 removal), and the overall removal of EE2 was determined to be 99% (sorption + biodegradation). AS used directly from a WWTP without acclimation removed EE2 only through sorption (88% removal of EE2). Therefore, higher nitrifying activity developed by acclimating AS allowed almost complete removal of EE2.
Ludiwine Clouzot, Pierre Doumenq, Nicolas Roche, Benoît Marrot. Kinetic parameters for 17α-ethinylestradiol removal by nitrifying activated sludge developed in a membrane bioreactor. Bioresource Technology, 2010, 101 (16), pp.6425-6431. ⟨10.1016/j.biortech.2010.03.039⟩. ⟨hal-01024728⟩
J-H Ferrasse, I. Seyssiecq, N. Roche. Les procédés de gazéification comme alternative pour la valorisation de boues de stations d'épuration des eaux usées. Environnement, Ingénierie & Développement, 2003, N°30 - 2ème Trimestre 2003, pp.20-24. ⟨10.4267/dechets-sciences-techniques.2446⟩. ⟨hal-03178157⟩ Plus de détails...
Le devenir des boues de stations d'épuration des eaux usées (Step) est un problème crucial posé aux pays industrialisés. En effet la quantité de boues produite en Step ne va cesser d’augmenter avec les croissances démographique et économique, ainsi que le nombre et la performance des Step des eaux usées. Actuellement, le traitement des boues de Step se fait par différentes filières, dont le nombre est limité. Quel que soit le devenir de ces filières et sans créer de polémiques particulières elles ne pourront, dans tous les cas, pas absorber ce volume croissant. Il devient dès lors nécessaire de diversifier les méthodes de traitement pour répondre aux problèmes posés par la gestion de ce déchet. Dans ce cadre, les nouvelles filières de traitement par valorisation thermochimiques semblent des plus intéressantes. En effet, elles présentent en plus de la capacité de traitement, l’avantage de produire des composés « stockables » et facilement «valorisables». Nous traiterons ainsi, dans cet article, de l'intérêt de développer les procédés de gazéification des boues de Step.
J-H Ferrasse, I. Seyssiecq, N. Roche. Les procédés de gazéification comme alternative pour la valorisation de boues de stations d'épuration des eaux usées. Environnement, Ingénierie & Développement, 2003, N°30 - 2ème Trimestre 2003, pp.20-24. ⟨10.4267/dechets-sciences-techniques.2446⟩. ⟨hal-03178157⟩
Journal: Environnement, Ingénierie & Développement