Christian Drakidès - Academia.edu (original) (raw)
Papers by Christian Drakidès
Water Science and Technology, Nov 1, 1993
An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabil... more An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabilization ponds was conducted. The objective was to adapt the treatment by waste stabilization ponds (WSP) to Tunisian conditions. The obtained results show that the average values of removal are about 72% for BOD, 65% for COD and more than 50% for ammonia nitrogen. The phosphate concentration was influenced by release of phosphate from decomposition sediment The elimination of total coliform, faecal coliform and faecal streptococci is between 99.3% and 99.99%. The most rate reduction was registered during the warm months which coincide with the irrigation season. The sediment accumulation is taken mainly in the first pond: the deposition rate is high (5 cm/year). In the three maturation ponds, it ranges from 1.3 to 1.6 cm/year. The WSP can be designed to satisfy Tunisian conditions. Because of favourable climate, loading can be much higher than those reported in the literature and some of the disadvantages of the pond system can be reduced. So we can economize in evaporation of effluent which is considered as a resource of irrigation in agriculture and we can reduce the surface area.
Revue Marocaine des Sciences Agronomiques et Vétérinaires, Oct 10, 2010
~-lll ~I ~i 3 ,4.:~1 d~1 ~ ~ ~1 ~I ùl~1 ,.JI ~ ,ù~1 ~ ~)I ~I ~. .j~1 ~ ~ 4:Jc.
Journal français d'hydrologie, 1984
Differents materiaux naturels (sable, gravier...) ont ete utilises comme garnissage dans des colo... more Differents materiaux naturels (sable, gravier...) ont ete utilises comme garnissage dans des colonnes experimentales de traitement complementaire d'effluent de fosse septique.Bien que de bons resultats d'abattements de pollution et de germes aient ete obtenus dans presque tous les cas, la description des micro-ecosystemes montre des variations de nature et de distribution verticale de la microfaune. Ces parametres sont suspectes etre en relation etroite avec la structure fine et les caracteristiques hydrauliques du materiau utilise.
Water Science and Technology, 2003
Faecal coliform removal in stabilisation ponds is highly dependent on shortest water retention ti... more Faecal coliform removal in stabilisation ponds is highly dependent on shortest water retention times. Tracer tests have been performed in a 3,300 m2 and 1.0 m deep pond, located in Southern France, to measure the retention times and bring light on the main influencing factors and mechanisms. Tracer concentrations were monitored at the outlet and 60 locations within the pond - at the surface, mid depth and the bottom of the water column. Pond water temperatures were measured at different depths and locations, together with pH, DO and redox potential. Wind velocity and rainfall were recorded. Water quality was monitored at the inlet, outlet and within the pond. Water retention times were shown to be strongly affected by weather conditions. Windy periods appeared to favour mixing regardless of the season. In sunny periods of spring and summer, a clear stratification was observed during daytime and vanished gradually during the night, suggesting alternation of mixed and stratified hydro...
Abstract. Highly toxic industrial effluents are often difficult to treat in biological wastewater... more Abstract. Highly toxic industrial effluents are often difficult to treat in biological wastewater treatment plants (BWWTP). Results obtained during a previous pilot-plant study allowed the identification of key parameters needed for the degradation of high concentrations of cyanides, thiocyanates and ammonium[13]. Kinetic models and parameter values were given for the pilot conditions using a synthetic effluent and commercial bacterial inoculums (Ecosynergie Inc.). In the present paper, these results have been applied to an existing full-scale BWWTP that was treating wastewaters from the coke and steel industry. The full-scale BWWTP contained the same contaminants and bacterial inoculums that were used in the pilot study. A conceptual hydraulic model of the BWWTP was built using STELLA software (ISEE Systems) and was adapted to the main contaminants undergoing degradation in the waste stream, using the same kinetics and parameters determined during the pilot study for the degradatio...
Infiltration-percolation is an extensive technique used to remove microorganisms from secondary e... more Infiltration-percolation is an extensive technique used to remove microorganisms from secondary effluents. It consists in intermittently infiltrating wastewater in unsaturated sand beds. Biomass expansion is managed through alternate operation and drying periods. Secondary effluent infiltration tests were performed on sand columns. Operation schedules were 4 days operation and 1 to 5 days drying. Organic matter, faecal coliforms and enterococci were monitored. Drying periods were shown to highly affect the elimination of enteric bacteria. Alternating operation and drying periods commands organic matter availability, biomass development and enteric bacteria removal. It was demonstrated that bacteria elimination was not solely related to water retention times and oxygen availability. Other factors, physical or biological, have also a key role in removal performances.
Water Science & Technology, 2009
Environmental monitoring of biological wastewater treatment plants (BWWTP) treating industrial ef... more Environmental monitoring of biological wastewater treatment plants (BWWTP) treating industrial effluents produces large amount of data. Frequent sampling is done in the influent and effluent but also in intermediate points. Samples are analyzed for classical and specific contaminants and physical-chemical parameters are monitored. In this paper data from a BWWTP treating the effluents of a coke and steel-processing factory are analyzed. Due to a complex situation, this BWWTP gave poor performances that did not match environmental regulations, meanwhile upgrading proved to be uneasy. Data analysis using principal component analyses (PCA) or kinetic modeling with a Haldane model was unsuccessful in handling these data, which was attributed to undetermined toxic effects. A new methodology is reported, that allowed to identify a kinetics for thiocyanate degradation and a relation between pH and toxic effects. This analysis of the plant data allowed to make hypothesis on the process cont...
Water Research, 1980
ABSTRACT The microfauna of activated sludge is well known as a potential indicator for operationa... more ABSTRACT The microfauna of activated sludge is well known as a potential indicator for operational control of biological treatment systems. An experiment was carried out during start up of an industrial scale pilot plant which was led with municipal sewage. Density of microfauna was evaluated using a counting chamber technique, and the results correlated with physicochemical factors. It was found that: the counting chamber technique is quite reliable provided the investigated volume reaches 10 mm3; grouping of microfauna by trophic characteristics makes the observation easier for the non-specialists without loosing too much information: and the evolution of microfauna is determined by a set of parameters for which epuration yield does not play a major role.RésuméThe microfauna of activated sludge is well known as a potential indicator for operational control of biological treatment systems. An experiment was carried out during start up of an industrial scale pilot plant which was led with municipal sewage. Density of microfauna was evaluated using a counting chamber technique, and the results correlated with physicochemical factors. It was found that: the counting chamber technique is quite reliable provided the investigated volume reaches 10 mm3; grouping of microfauna by trophic characteristics makes the observation easier for the non-specialists without loosing too much information: and the evolution of microfauna is determined by a set of parameters for which epuration yield does not play a major role.
Powder Technology, 1983
ABSTRACT In this paper, the literature on the characterization of floc particles is reviewed. The... more ABSTRACT In this paper, the literature on the characterization of floc particles is reviewed. The quantification of the biological floc characteristics is difficult and the problem of methodology arises. The literature-review permits the following conclusions: •the variability of the results is a function of method used;•the optical methods are the most useful, but their application is long and tedious;•the dimensional characteristics alone are inadequate, and the determination of other parameters would be interesting.
Journal of Applied Polymer Science, 2007
Biodegradation of poy(L-lactide) (PLLA) films and filaments recovered with hydrophilic layer (con... more Biodegradation of poy(L-lactide) (PLLA) films and filaments recovered with hydrophilic layer (contact angle y H2O ¼ 148, surface energy g s ¼ 70.9 mJ m À2) from allylamine plasma polymerization was investigated under aerobic conditions in sludge. XPS and FTIR-ATR analysis of the plasma layer showed 14.4% N and 16.6% O mainly as amide group. Optical microscopy showed much bacteria colonies on treated PLLA surface than on untreated one. Weight loss and oxygen consumption after 65 days were 4-5% and 4 mg h À1 per gram polymer respectively. The fact that biodegradation lag-phase for treated PLLA was released quicker (7 days) than untreated one (14 days), could be related to the presence of hydrophilic plasma layer that improved swelling-dissolution of hydrolyzed molecular fragments. 2007
Journal of Polymers and the Environment, 2010
Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many e... more Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many end up in wastewater and, later on, in wastewater-treatment plants. In order to gain an insight into their fate in such plants, fluorescence and radioactivity labelings were compared using a lab-scale reactor designed to mimic industrial conditions. Two fermentation media were considered, namely a mixture of E402 and
Journal of Civil & Environmental Engineering, 2012
Water Science and Technology, 1993
An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabil... more An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabilization ponds was conducted. The objective was to adapt the treatment by waste stabilization ponds (WSP) to Tunisian conditions. The obtained results show that the average values of removal are about 72% for BOD, 65% for COD and more than 50% for ammonia nitrogen. The phosphate concentration was influenced by release of phosphate from decomposition sediment The elimination of total coliform, faecal coliform and faecal streptococci is between 99.3% and 99.99%. The most rate reduction was registered during the warm months which coincide with the irrigation season. The sediment accumulation is taken mainly in the first pond: the deposition rate is high (5 cm/year). In the three maturation ponds, it ranges from 1.3 to 1.6 cm/year. The WSP can be designed to satisfy Tunisian conditions. Because of favourable climate, loading can be much higher than those reported in the literature and some of...
SUMMARY Urban or indu striai waste water organlc pollution is most otten treated by aérobic biolo... more SUMMARY Urban or indu striai waste water organlc pollution is most otten treated by aérobic biological Systems. In this case, commonly used activated sludge plants need large tanks. Membrane bioreactors would give compactness and very high and constant quality erfluent. Up to now, organic membranes bave been mainly utilized for polishing effluents from conventional secondary treatment. MEMCOR process, using hollow libers membranes, aliows permeate fluxes of 100 l/b.m2 for several months under a 1 bar pressure. Chatze (1990), using inorganic membranes for urban waste water treatment, reached high organic and nitrogen removal. Biomass was about 10 to 20 g/l and permeate fluxes of 20 and 28 l/h.m 2 at 1.1 and 1.4 bar transmembrane pressure with residuals less than 20 ppm COD and SSM and 5 ppm TKN.
Chemosphere, 2006
A bacterial strain B2 that oxidizes arsenite into arsenate was isolated from the biofilm growing ... more A bacterial strain B2 that oxidizes arsenite into arsenate was isolated from the biofilm growing in a biological groundwater treatment process used for Fe removal. This strain is phylogenetically and morphologically different from the genus Leptothrix commonly encountered in biological iron oxidation processes. T-RFLP fingerprint of the biofilm revealed that this isolated strain B2 corresponds to the major population of the bacterial community in the biofilm. Therefore, it is probably one of the major contributors to arsenic removal in the treatment process.
animal, 2013
Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous ... more Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous fish and phytoplankton. The fish recycle nutrients by consuming live (and dead) algae and provide the inorganic carbon to fuel the growth of live algae. In the meanwhile, algae purify the water and generate the oxygen required by fishes. Such mechanism stabilizes the functioning of an artificially recycling ecosystem, as exemplified by combining the euryhaline tilapiaSarotherodon melanotheron heudelotiiand the unicellular algaChlorellasp. Feed addition in this ecosystem results in faster fish growth but also in an increase in phytoplankton biomass, which must be limited. In the prototype described here, the algal population control is exerted by herbivorous zooplankton growing in a separate pond connected in parallel to the fish–algae ecosystem. The zooplankton production is then consumed by tilapia, particularly by the fry and juveniles, when water is returned to the main circuit.Chlore...
Laboratory Robotics and Automation, 1997
... Additional Information. How to Cite. Frouji, MA, Bahlaoui, MA, Baleux, B., Drakidès, C., Mahi... more ... Additional Information. How to Cite. Frouji, MA, Bahlaoui, MA, Baleux, B., Drakidès, C., Mahi,M., Choukrad, M. and Zakarya, D. (1997), Use of neural networks as tool for the control of the biological pollution. Laboratory Robotics and Automation, 9: 243247. ...
Water Science and Technology, Nov 1, 1993
An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabil... more An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabilization ponds was conducted. The objective was to adapt the treatment by waste stabilization ponds (WSP) to Tunisian conditions. The obtained results show that the average values of removal are about 72% for BOD, 65% for COD and more than 50% for ammonia nitrogen. The phosphate concentration was influenced by release of phosphate from decomposition sediment The elimination of total coliform, faecal coliform and faecal streptococci is between 99.3% and 99.99%. The most rate reduction was registered during the warm months which coincide with the irrigation season. The sediment accumulation is taken mainly in the first pond: the deposition rate is high (5 cm/year). In the three maturation ponds, it ranges from 1.3 to 1.6 cm/year. The WSP can be designed to satisfy Tunisian conditions. Because of favourable climate, loading can be much higher than those reported in the literature and some of the disadvantages of the pond system can be reduced. So we can economize in evaporation of effluent which is considered as a resource of irrigation in agriculture and we can reduce the surface area.
Revue Marocaine des Sciences Agronomiques et Vétérinaires, Oct 10, 2010
~-lll ~I ~i 3 ,4.:~1 d~1 ~ ~ ~1 ~I ùl~1 ,.JI ~ ,ù~1 ~ ~)I ~I ~. .j~1 ~ ~ 4:Jc.
Journal français d'hydrologie, 1984
Differents materiaux naturels (sable, gravier...) ont ete utilises comme garnissage dans des colo... more Differents materiaux naturels (sable, gravier...) ont ete utilises comme garnissage dans des colonnes experimentales de traitement complementaire d'effluent de fosse septique.Bien que de bons resultats d'abattements de pollution et de germes aient ete obtenus dans presque tous les cas, la description des micro-ecosystemes montre des variations de nature et de distribution verticale de la microfaune. Ces parametres sont suspectes etre en relation etroite avec la structure fine et les caracteristiques hydrauliques du materiau utilise.
Water Science and Technology, 2003
Faecal coliform removal in stabilisation ponds is highly dependent on shortest water retention ti... more Faecal coliform removal in stabilisation ponds is highly dependent on shortest water retention times. Tracer tests have been performed in a 3,300 m2 and 1.0 m deep pond, located in Southern France, to measure the retention times and bring light on the main influencing factors and mechanisms. Tracer concentrations were monitored at the outlet and 60 locations within the pond - at the surface, mid depth and the bottom of the water column. Pond water temperatures were measured at different depths and locations, together with pH, DO and redox potential. Wind velocity and rainfall were recorded. Water quality was monitored at the inlet, outlet and within the pond. Water retention times were shown to be strongly affected by weather conditions. Windy periods appeared to favour mixing regardless of the season. In sunny periods of spring and summer, a clear stratification was observed during daytime and vanished gradually during the night, suggesting alternation of mixed and stratified hydro...
Abstract. Highly toxic industrial effluents are often difficult to treat in biological wastewater... more Abstract. Highly toxic industrial effluents are often difficult to treat in biological wastewater treatment plants (BWWTP). Results obtained during a previous pilot-plant study allowed the identification of key parameters needed for the degradation of high concentrations of cyanides, thiocyanates and ammonium[13]. Kinetic models and parameter values were given for the pilot conditions using a synthetic effluent and commercial bacterial inoculums (Ecosynergie Inc.). In the present paper, these results have been applied to an existing full-scale BWWTP that was treating wastewaters from the coke and steel industry. The full-scale BWWTP contained the same contaminants and bacterial inoculums that were used in the pilot study. A conceptual hydraulic model of the BWWTP was built using STELLA software (ISEE Systems) and was adapted to the main contaminants undergoing degradation in the waste stream, using the same kinetics and parameters determined during the pilot study for the degradatio...
Infiltration-percolation is an extensive technique used to remove microorganisms from secondary e... more Infiltration-percolation is an extensive technique used to remove microorganisms from secondary effluents. It consists in intermittently infiltrating wastewater in unsaturated sand beds. Biomass expansion is managed through alternate operation and drying periods. Secondary effluent infiltration tests were performed on sand columns. Operation schedules were 4 days operation and 1 to 5 days drying. Organic matter, faecal coliforms and enterococci were monitored. Drying periods were shown to highly affect the elimination of enteric bacteria. Alternating operation and drying periods commands organic matter availability, biomass development and enteric bacteria removal. It was demonstrated that bacteria elimination was not solely related to water retention times and oxygen availability. Other factors, physical or biological, have also a key role in removal performances.
Water Science & Technology, 2009
Environmental monitoring of biological wastewater treatment plants (BWWTP) treating industrial ef... more Environmental monitoring of biological wastewater treatment plants (BWWTP) treating industrial effluents produces large amount of data. Frequent sampling is done in the influent and effluent but also in intermediate points. Samples are analyzed for classical and specific contaminants and physical-chemical parameters are monitored. In this paper data from a BWWTP treating the effluents of a coke and steel-processing factory are analyzed. Due to a complex situation, this BWWTP gave poor performances that did not match environmental regulations, meanwhile upgrading proved to be uneasy. Data analysis using principal component analyses (PCA) or kinetic modeling with a Haldane model was unsuccessful in handling these data, which was attributed to undetermined toxic effects. A new methodology is reported, that allowed to identify a kinetics for thiocyanate degradation and a relation between pH and toxic effects. This analysis of the plant data allowed to make hypothesis on the process cont...
Water Research, 1980
ABSTRACT The microfauna of activated sludge is well known as a potential indicator for operationa... more ABSTRACT The microfauna of activated sludge is well known as a potential indicator for operational control of biological treatment systems. An experiment was carried out during start up of an industrial scale pilot plant which was led with municipal sewage. Density of microfauna was evaluated using a counting chamber technique, and the results correlated with physicochemical factors. It was found that: the counting chamber technique is quite reliable provided the investigated volume reaches 10 mm3; grouping of microfauna by trophic characteristics makes the observation easier for the non-specialists without loosing too much information: and the evolution of microfauna is determined by a set of parameters for which epuration yield does not play a major role.RésuméThe microfauna of activated sludge is well known as a potential indicator for operational control of biological treatment systems. An experiment was carried out during start up of an industrial scale pilot plant which was led with municipal sewage. Density of microfauna was evaluated using a counting chamber technique, and the results correlated with physicochemical factors. It was found that: the counting chamber technique is quite reliable provided the investigated volume reaches 10 mm3; grouping of microfauna by trophic characteristics makes the observation easier for the non-specialists without loosing too much information: and the evolution of microfauna is determined by a set of parameters for which epuration yield does not play a major role.
Powder Technology, 1983
ABSTRACT In this paper, the literature on the characterization of floc particles is reviewed. The... more ABSTRACT In this paper, the literature on the characterization of floc particles is reviewed. The quantification of the biological floc characteristics is difficult and the problem of methodology arises. The literature-review permits the following conclusions: •the variability of the results is a function of method used;•the optical methods are the most useful, but their application is long and tedious;•the dimensional characteristics alone are inadequate, and the determination of other parameters would be interesting.
Journal of Applied Polymer Science, 2007
Biodegradation of poy(L-lactide) (PLLA) films and filaments recovered with hydrophilic layer (con... more Biodegradation of poy(L-lactide) (PLLA) films and filaments recovered with hydrophilic layer (contact angle y H2O ¼ 148, surface energy g s ¼ 70.9 mJ m À2) from allylamine plasma polymerization was investigated under aerobic conditions in sludge. XPS and FTIR-ATR analysis of the plasma layer showed 14.4% N and 16.6% O mainly as amide group. Optical microscopy showed much bacteria colonies on treated PLLA surface than on untreated one. Weight loss and oxygen consumption after 65 days were 4-5% and 4 mg h À1 per gram polymer respectively. The fact that biodegradation lag-phase for treated PLLA was released quicker (7 days) than untreated one (14 days), could be related to the presence of hydrophilic plasma layer that improved swelling-dissolution of hydrolyzed molecular fragments. 2007
Journal of Polymers and the Environment, 2010
Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many e... more Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many end up in wastewater and, later on, in wastewater-treatment plants. In order to gain an insight into their fate in such plants, fluorescence and radioactivity labelings were compared using a lab-scale reactor designed to mimic industrial conditions. Two fermentation media were considered, namely a mixture of E402 and
Journal of Civil & Environmental Engineering, 2012
Water Science and Technology, 1993
An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabil... more An experimental study of the domestic wastewater treatment in a series of four pilot-scale stabilization ponds was conducted. The objective was to adapt the treatment by waste stabilization ponds (WSP) to Tunisian conditions. The obtained results show that the average values of removal are about 72% for BOD, 65% for COD and more than 50% for ammonia nitrogen. The phosphate concentration was influenced by release of phosphate from decomposition sediment The elimination of total coliform, faecal coliform and faecal streptococci is between 99.3% and 99.99%. The most rate reduction was registered during the warm months which coincide with the irrigation season. The sediment accumulation is taken mainly in the first pond: the deposition rate is high (5 cm/year). In the three maturation ponds, it ranges from 1.3 to 1.6 cm/year. The WSP can be designed to satisfy Tunisian conditions. Because of favourable climate, loading can be much higher than those reported in the literature and some of...
SUMMARY Urban or indu striai waste water organlc pollution is most otten treated by aérobic biolo... more SUMMARY Urban or indu striai waste water organlc pollution is most otten treated by aérobic biological Systems. In this case, commonly used activated sludge plants need large tanks. Membrane bioreactors would give compactness and very high and constant quality erfluent. Up to now, organic membranes bave been mainly utilized for polishing effluents from conventional secondary treatment. MEMCOR process, using hollow libers membranes, aliows permeate fluxes of 100 l/b.m2 for several months under a 1 bar pressure. Chatze (1990), using inorganic membranes for urban waste water treatment, reached high organic and nitrogen removal. Biomass was about 10 to 20 g/l and permeate fluxes of 20 and 28 l/h.m 2 at 1.1 and 1.4 bar transmembrane pressure with residuals less than 20 ppm COD and SSM and 5 ppm TKN.
Chemosphere, 2006
A bacterial strain B2 that oxidizes arsenite into arsenate was isolated from the biofilm growing ... more A bacterial strain B2 that oxidizes arsenite into arsenate was isolated from the biofilm growing in a biological groundwater treatment process used for Fe removal. This strain is phylogenetically and morphologically different from the genus Leptothrix commonly encountered in biological iron oxidation processes. T-RFLP fingerprint of the biofilm revealed that this isolated strain B2 corresponds to the major population of the bacterial community in the biofilm. Therefore, it is probably one of the major contributors to arsenic removal in the treatment process.
animal, 2013
Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous ... more Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous fish and phytoplankton. The fish recycle nutrients by consuming live (and dead) algae and provide the inorganic carbon to fuel the growth of live algae. In the meanwhile, algae purify the water and generate the oxygen required by fishes. Such mechanism stabilizes the functioning of an artificially recycling ecosystem, as exemplified by combining the euryhaline tilapiaSarotherodon melanotheron heudelotiiand the unicellular algaChlorellasp. Feed addition in this ecosystem results in faster fish growth but also in an increase in phytoplankton biomass, which must be limited. In the prototype described here, the algal population control is exerted by herbivorous zooplankton growing in a separate pond connected in parallel to the fish–algae ecosystem. The zooplankton production is then consumed by tilapia, particularly by the fry and juveniles, when water is returned to the main circuit.Chlore...
Laboratory Robotics and Automation, 1997
... Additional Information. How to Cite. Frouji, MA, Bahlaoui, MA, Baleux, B., Drakidès, C., Mahi... more ... Additional Information. How to Cite. Frouji, MA, Bahlaoui, MA, Baleux, B., Drakidès, C., Mahi,M., Choukrad, M. and Zakarya, D. (1997), Use of neural networks as tool for the control of the biological pollution. Laboratory Robotics and Automation, 9: 243247. ...