WO2005035451A1 - Procede de traitement par voie chimique d'un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications - Google Patents
Procede de traitement par voie chimique d'un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications Download PDFInfo
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- WO2005035451A1 WO2005035451A1 PCT/FR2004/002528 FR2004002528W WO2005035451A1 WO 2005035451 A1 WO2005035451 A1 WO 2005035451A1 FR 2004002528 W FR2004002528 W FR 2004002528W WO 2005035451 A1 WO2005035451 A1 WO 2005035451A1
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- liquid
- nitrates
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/70—Treatment of water, waste water, or sewage by reduction
- C02F1/705—Reduction by metals
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
- C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
- C02F1/467—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction
- C02F1/4676—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electroreduction
- C02F1/4678—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electroreduction of metals
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
- C02F2101/163—Nitrates
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/06—Contaminated groundwater or leachate
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
Definitions
- the present invention relates to a method for the chemical treatment of a liquid medium charged with nitrates.
- the invention also relates to a device for treating such a liquid medium and the applications of this method.
- Liquid effluents resulting from the drainage of crop soils are subject to regulations aimed at reducing the quantity of pollutants contained in these effluents. Among these pollutants, nitrates are more particularly targeted.
- liquid effluents from drainage water can contain a nitrate concentration of up to 3 g / L for a maximum flow of
- the invention relates to a method for treating a liquid medium loaded with nitrates which makes it possible to reduce the concentration of nitrates and does not lead to the formation of other polluting species which can harm the environment.
- the invention lies also in a device for treating a liquid medium loaded with nitrates and in the possible applications of the process of the invention.
- the process of the invention comprises at least one step of bringing zinc into contact with said liquid medium, the pH of which is less than 4.
- the pH of the said liquid medium is kept fixed by regular adjustment consisting in adding an appropriate amount of acid to the liquid medium.
- the acid used is hydrochloric acid.
- the pH adjustment can be carried out at least every half hour for the duration of the treatment.
- the temperature of the liquid medium during the contacting step can be greater than 20 ° C but can also be approximately 20 ° C.
- the zinc is in the form of powder.
- the mass ratio between the zinc and the nitrates in solution is preferably at least 5.
- the liquid medium is subjected to stirring.
- the stirring can be carried out by pulsations or static mixers.
- the liquid medium undergoes stirring at a speed of at least 0.55 m / s.
- the method of the invention makes it possible to treat a liquid medium whose initial concentration of nitrates is greater than 25 mg / L and also greater than 50 mg / L.
- the zinc is in the form of chips.
- the zinc shavings be degreased and rinsed with distilled water.
- the contact surface of the zinc with the liquid medium is at least 0.0156 m 2 / L and more advantageously about 0.25 m 2 / L.
- the liquid medium can consist of drainage water in which the nitrate concentration can be greater than 1 g / L.
- the flow rate of circulation of the liquid medium in contact with the zinc is greater than 0.005 m / s and preferably approximately 0.01 m / s.
- the method can also comprise a step of electrolysis of the liquid medium.
- This electrolysis step can consist in circulating the liquid medium 68 in at least one electrolysis cell 110a, 110b, 110c, llOd, 110e, IlOf in which a current flows between two electrodes respectively anode 109a, 109b, 109c, 109d and cathodic 108a, 108b, 108c.
- each cathode electrode 108a, 108b, 108c is produced by compression of grains of carbon between two perforated plates 116b, 116b 'in which at least one electrode means 117 is pressed while being connected to the negative pole of a generator.
- the anode electrode 109a, 109b, 109c, 109d is produced by compression of zinc shavings between two perforated plates 118a, 118a ', 118b, 118b' in which at least one means forming electrode 119b, 119c is pressed in while connected to the positive pole of a generator.
- the liquid medium 68 circulates in at least six electrolysis cells 110a, 110b, 110c, 11Od, 110e, IlOf.
- the pH of the liquid medium is kept greater than 5 and preferably equal to 10 throughout the duration of the electrolysis step.
- the potential applied between the anode electrodes 109a, 109b, 109c and cathode electrodes 108a, 108b, 108c " is preferably about 2 volts for a current between 1.5 and 1.8 amperes per liter of solution treated.
- the invention also relates to a device for the chemical treatment of a liquid medium loaded with nitrates comprising at least one nitrate reduction enclosure 56 comprising a liquid inlet 57, at least one layer of zinc 70, 85a, 85b, 85c, 99a, 99b, 99c, 99d, 99e, 99f, 99g, a means for circulating the said liquid medium 59 through the said zinc layer and an outlet for the liquid medium 58 from the enclosure 56.
- the nitrates reduction enclosure 56 is vertically arranged and has at least one layer of zinc 70, 85a, 85b, 85c, 99a, 99b, 99c, 99d, 99e, 99f, 99g which is transversely disposed over the entire width of the enclosure 56 and which is produced by compression of zinc shavings between two perforated plates 71, 72, 86a, 86a ', 86b, 86b', 86c, 86c ', the liquid inlet 57 is arranged in the lower part of the enclosure 56, the liquid outlet 58 is " arranged in the upper part of the enclosure 56 and the device further comprises a recirculation pump 59 making it possible to ensure the circulation and recirculation of the liquid from the inlet 57 to the outlet 58 through all the zinc layers 70, 85a, 85b, 85c , 99a, 99b, 99c, 99d, 99e, 99f, 99g.
- each zinc layer 70, 85a, 85b, 85c, 99a, 99b, 99c, 99d, 99e, 99f, 99g is less than 10 cm.
- the enclosure 56 may include a liquid agitation system 75 making it possible to agitate the liquid circulating in the enclosure 56 above each layer of zinc 70, 85a, 85b, 85c, 99a, 99b, 99c , 99d, 99e, 99f, 99g by forming a corresponding agitation zone 78, 92a, 92b, 92c, 99al, 99bl, 99cl, 99dl, 99el, 99fl, 99gl.
- the stirring speed of the liquid in each stirring zone 78, 92a, 92b, 92c, 99al, 99bl, 99cl, 99dl, 99el, 99fl, 99gl is about 0.85 m / s.
- at least one out of two stirring zones is connected to a pH regulator.
- the pH regulator may include at least one probe 93a, 93b, 93c measuring the pH in the corresponding stirring zone 78, 92a, 92b, 92c, 99al, 99bl, 99cl, 99dl, 99el, 99fl, 99gl , a control unit 94 and an acid circulation pump 95.
- the pH of the liquid medium is maintained at a value less than 6 by the pH regulator and very preferably at a value between 2 and 3.
- the speed of circulation of the liquid in the enclosure 56 is preferably about 0.01 m / s.
- the enclosure 56 advantageously comprises at least three layers of zinc 70, 85a, 85b, 85c, 99a, 99b, 99c, 99d, 99e, 99f, 99g.
- the device of the invention may further comprise a zinc reduction enclosure 106 in which the liquid 68 circulates at the outlet of the nitrates reduction enclosure 56.
- the zinc reduction enclosure 106 comprises at least an electrolysis cell 110a, 110b, 110c, llOd, 110e, IlOf.
- each cathode electrode 108a, 108b, 108c of the respective electrolysis cells 110a, 110b, 110c, llOd, 110e, IlOf is produced by compression of carbon grains between two perforated plates 116b, 116b 'and in that at least an electrode means 117 is driven into the grains of carbon and connected to the negative pole of a current generator.
- each anode electrode 109a, 109b, 109c, 109d of the electrolysis cells respective 110a, 110b, 110c, 110d, 110e, IlOf is produced by compression of zinc chips between two perforated plates 118a, 118a '; 118b, 118b 'and in that at least one electrode means 119b, 119c is pressed into the zinc shavings and connected to the positive pole of a current generator.
- the zinc reduction enclosure 106 can comprise at least three electrolysis cells 110a, 110b, 110c, 110d, 110e, IlOf.
- the .zinc reduction enclosure 106 is vertically disposed and the anode electrodes 109a, 109b, 109c, 109d and cathode electrodes 108a, 108b, 108c forming the corresponding electrolysis cells 110a, 110b, 110c, 11Od, 110e, IlOf are transversely arranged over the entire width of the enclosure 106 so that all the liquid circulating in the enclosure 106 passes through the electrolysis cells, the liquid inlet 111, 115 is arranged in the lower part of the enclosure 106, the liquid outlet 115 is arranged in the upper part of the enclosure 106 and the device of the invention further comprises a recirculation pump 113 making it possible to circulate and recirculate the liquid from the inlet 111, 115 up to exit 112 through all the electrolysis cells 110a, 110b, 110c, llOd, 110e, IlOf.
- a recirculation pump 113 making it possible to circulate and recirculate the liquid from the inlet
- the enclosure 106 may further comprise a pH regulator maintaining the pH of the liquid medium circulating in the zinc reduction enclosure 106 at a value greater than 7.
- the method and the device of the invention can be used to treat any liquid medium loaded with nitrates but also to treat crop drainage water.
- FIG. 1 represents the evolution of the concentrations of nitrates in the liquid medium as a function of the treatment time when zinc powder is used;
- FIGS. 1 represents the evolution of the concentrations of nitrates in the liquid medium as a function of the treatment time when zinc powder is used;
- FIGS. 1 represents the evolution of the concentrations of nitrates in the liquid medium as a function of the treatment time when zinc powder is used;
- FIGS. 1 represents the evolution of the concentrations of nitrates in the liquid medium as a function of the treatment time when zinc powder is used;
- FIGS. 2a and 2b show the evolution of the nitrogen concentrations corresponding to a factor close to the concentrations of nitrates and nitrites in the liquid medium as a function of the treatment time with and without adjustment of the pH;
- FIGS. 3a and 3b show the evolution of the nitrogen concentrations corresponding to a factor close to the concentrations of nitrates and nitrites in the liquid medium as a function of the treatment time according to the frequency of adjustment of the pH;
- FIGS. 4a and 4b show the evolution of the nitrogen concentrations corresponding to a factor close to the concentrations of nitrates and nitrites in the liquid medium as a function of the treatment time according to the temperature of the reaction medium;
- FIG. 5 represents the evolution of Ln [N0 2 " ] as a function of the treatment time
- FIG. 6 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time according to the nature of the metals used
- FIG. 7 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time according to the speed of agitation of the liquid medium
- FIG. 8 represents the evolution of Ln C / Co in nitrites as a function of time treatment according to the stirring speed of the liquid medium
- - Figure 9 represents the evolution of the concentration of nitrites in the liquid medium in function of the treatment time according to the pH of the liquid medium
- FIG. 6 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time according to the nature of the metals used
- FIG. 7 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time according to the speed of agitation of the liquid
- FIG. 10 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time according to the mass of zinc powder used
- FIG. 11 represents the change in the concentration of nitrites in the liquid medium as a function of the treatment time depending on whether the zinc used is in the form of powder or of chips
- FIG. 12 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time when zinc shavings are used and according to the pH of the liquid medium
- - Figure 13 shows the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time according to the initial concentration of nitrites
- FIG. 11 represents the change in the concentration of nitrites in the liquid medium as a function of the treatment time depending on whether the zinc used is in the form of powder or of chips
- FIG. 12 represents the evolution of the concentration of nitrites in the liquid medium as a function of the treatment time when zinc shavings are used and according to the pH of the liquid medium
- FIG. 14 represents the change in the concentration of nitrites in the liquid medium as a function of the treatment time when the liquid medium is initially loaded with nitrates;
- FIG. 15 represents the evolution of Ln C / Co into nitrites as a function of the treatment time according to the masses and forms of zinc used;
- FIG. 16 represents the evolution of the log d ([N0 2 " ] / dt) as a function of the log (Zn);
- FIG. 17 represents the evolution of ' ln d ([N0 2 ⁇ ] / dt) as a function of the ln (Zn) according to the pH of the liquid medium;
- FIG. 18 represents the evolution of Ln C / Co into nitrites as a function of the treatment time according to the pH of the liquid medium;
- FIG. 19 represents the evolution of the log d ([ N0 2 " ] / dt) as a function of the log (H + ) according to the pH of the liquid medium;
- FIG. 20 represents the evolution of the log d ([N0 2 " ] / dt) as a function of the log (NO 2- ) according to the pH of the liquid medium;
- FIG. 21 represents the evolution of the log d ([NC ⁇ ] / dt) as a function of the log (NO 2- ) according to the pH of the liquid medium;
- FIG. 22 represents the evolution of the log d ([N0 2 " ] / dt) as a function of the log (NO 2" ) at pH 4;
- FIG. 23 represents the evolution of the concentrations of nitrates and nitrites as a function of the treatment time when the liquid medium consists of drainage water;
- FIGS. 24a and 24b represent the evolution of the concentrations of nitrates and nitrites as a function of the treatment time when the liquid medium consists of the drainage water according to the temperature of the reaction medium and when the pH is adjusted every half hour;
- FIG. 25a and 25b show the evolution of the concentrations of nitrates and nitrites in function of the treatment time when the liquid medium consists of the drainage water according to the temperature of the reaction medium when the pH is adjusted every quarter of an hour during the first hour of treatment and then every half hour;
- FIG. 26 represents the evolution of the nitrite concentration as a function of the treatment time according to the pH of the liquid medium;
- Figure 27 is a schematic representation of the device of the invention according to a first embodiment;
- FIG. 28 represents the evolution of the nitrite concentration as a function of the treatment time according to the pH and the mass of zinc shavings used when the liquid medium is treated in the device of the invention;
- FIG. 29 represents the evolution of the nitrite concentration as a function of the treatment time according to the pH and the mass of zinc shavings used when the liquid medium is treated in the device of the invention
- FIG. 30 represents the evolution of Ln C / Co in nitrites as a function of the treatment time when the liquid medium is treated in the device of the invention
- - Figure 31 is a schematic representation of the device of the invention according to a second embodiment
- Figure 32 is a schematic representation of the device of the invention according to a third embodiment when it also comprises a zinc reduction device
- Figure 33 is an enlargement of the circled part denoted XXXIII of Figure 32.
- FIG. 1 show that the nitrates can be reduced by zinc in solution.
- FIGS. 2 to 4 present l evolution of nitrogen concentrations corresponding to a factor close to the respective nitrates and nitrites concentrations in the form of histograms. More precisely, the nitrates concentrations are obtained by multiplying the nitrogen concentration by four and the nitrites concentrations are obtained by multiplying the nitrogen concentration by three.
- FIGS. 2a and 2b show the evolution of the nitrogen concentrations when the solution is maintained at a temperature of 80 ° C.
- the concentration of nitrates is less than 200 mg / L after 30 minutes of treatment and is void after one hour of treatment.
- the treatment efficiency in terms of reduction of the nitrates in solution is illustrated by the black bars 5a when the pH of the solution is maintained at a pH below 6 by adjustment carried out once per hour during the treatment and for a temperature of the reaction medium of 20 ° C.
- this pH adjustment is carried out every half hour during the treatment the concentration of nitrates represented by the black bar is zero after 1 hour of treatment.
- FIGS. 4a and 4b correspond to the evolution of the concentrations of nitrates illustrated by the black bars 7a, 7b, and of nitrites illustrated by the gray bar 8a when the pH of the solution is maintained at a value less than 6 during the treatment and for different reaction medium temperatures.
- the results of FIG. 4a corresponding to a temperature of the solution of 50 ° C. and those of FIG. 4b c to a temperature of the solution of 80 ° C.
- the rate of disappearance of the nitrates is greater than the temperature of 80 ° C. than the speed of disappearance of the nitrates when this temperature is maintained at 50 ° C. Indeed, after 30 minutes of treatment, the nitrate concentration is less than 200 mg / L when the medium temperature is 80 ° C while for a temperature of 50 ° C the nitrate concentration is almost identical to the initial concentration in nitrates of approximately 920 mg / L after half an hour of treatment.
- the results presented in FIGS. 2, 3 and 4 show that the adjustment of the pH and more generally the acidity of the reaction medium is a first parameter to be taken into account in the process of the invention and that the temperature of the medium reaction is also a parameter influencing the effectiveness of the treatment.
- N0 3 + Zn + 3H + -» HN0 2 + Zn 2+ + H 2 0 2HN0 2 + 2Zn + 4 H + - N 2 0 + 2Zn 2+ + 3H 2 0 2 N0 2 " + 3 Zn + 8H + ⁇ N 2 + 4H 2 0 + 3ZrT + N0 2 " + 3 Zn + 8H + - NH 4 + + 2 H 2 0 + 3 Zn 2+
- the method used to measure the nitrites in solution during the treatment is a colorimetric assay by molecular absorption spectrophotometry.
- Diazotization reagents - Amino-4-benzenesulfonamide 40g - Dichloride of N- (naphthyl-1) diamino-1, 2 ethane 2g - Orthophosphoric acid 100ml - Permuted water qs 1000ml Stock standard solution of nitrous nitrogen (N0 2 ) at 300mg / L - Sodium nitrite 492.8mg 0 - Permuted water qs 1000ml
- Table 1 The equipment used is as follows: - Cary 50 bio spectrophotometer, visible UV - LABMATE pipette with volume 1000-5000 1 for manual pH regulation and sample collection - Sartorius Professional Meter PP-15 pH meter - Eurostar Teflon shaker digital IK (50-2000 rpm) - Sartorius LA 230S scale - CONSORT R305 pH regulator
- the nitrites reduction measurements are carried out using an initial solution titrated to 1 g / L of nitrites and are carried out using sodium nitrite.
- the reduction is carried out in a batch reactor, that is to say in a beaker at room temperature.
- the initial volume of the nitrite solution is 1 liter and the pH was kept constant manually throughout the reaction by regular addition of 2M hydrochloric acid.
- the solution is stirred with a teflon magnetic rod and the zinc is added to the nitrite solution in powder form.
- Figure 6 shows the evolution of the nitrate concentration expressed in mg / L as a function of the treatment time expressed in minutes for three metals of different natures which are added to the solution of nitrites in stoichiometric proportions.
- Curve 10 represents the evolution of the concentration of nitrites when 10 g of zinc powder are added to the solution of nitrites
- curve 11 represents the evolution of the concentration of nitrates when 8.54 g of powder of iron are added to the nitrite solution
- curve 12 illustrates the evolution of the nitrite concentration when 4.13 g of aluminum powder are added to the solution.
- the "method of reducing nitrite comprises three steps, namely the transfer of nitrites to the metal surface, the reaction to the surface and transferring the products to the liquid volume, and the latter step may be neglected if it is considered that all of the nitrites are transformed into nitrogen, the transfer of nitrites to the active surface is a purely physical process based on the concentration gradient as a driving force and the basic equation is as follows:
- the mass transfer coefficient - K will depend on the hydrodynamic conditions and therefore in particular on the speed of agitation of the liquid medium.
- FIG. 9 illustrates the evolution of the nitrite concentration as a function of the treatment time expressed in minutes depending on the pH of the solution.
- curve 19 corresponds to a pH equal to 11
- curve 21 to a pH equal to 5.
- FIG. 11 illustrates the comparison between the evolution of the concentration of nitrites expressed in mg / L as a function of the treatment time expressed in minutes when the zinc is used in the form of powder and that when the zinc is used in the form of chips for a pH kept constant at 5 for the duration of the experiment in the solution, the stirring speed of this solution being 1.1 m / s.
- Curve 24 corresponds to the use of zinc chips for an exchange surface of 0.04 m 2
- curve 25 corresponds to the use of zinc powder for an exchange surface of 4.14 m 2 . From these two curves, it appears that the reduction of nitrites is slower with zinc shavings which can be explained by the reduction in the exchange surface which is approximately 100 times smaller in the case of the shavings compared. in the case of powder.
- the nitrite reduction speed is almost identical regardless of the initial nitrite concentration as shown by the results presented in FIG. 13 which represents the evolution of the nitrite concentration as a function of the treatment time expressed in minutes, on which curve 29 corresponds to the use of a nitrite solution with an initial nitrite concentration of more than 2000 mg / L, curve 28 at an initial nitrite concentration of around 1500 mg / L and curve 27 at an initial nitrite concentration of 1000 mg / L.
- Curves 27 to 29 correspond to treatments carried out at an adjusted pH 2 throughout the duration of the treatment, with a mass of chips of 15.79 g corresponding to an exchange surface of 0.04 m 2 per liter of solution and at a stirring speed of 1.375 m / s.
- the total reduction of the nitrites in solution is obtained in an approximately identical treatment time of 60 minutes.
- Tests with zinc shavings were also carried out using a solution loaded with nitrates with an initial concentration of 1 g / L and prepared from potassium nitrate. The reduction is carried out in a batch reactor in which 15.79 grams of zinc shavings are added to the nitrate solution with a volume of 1 liter.
- FIG. 14 shows the evolution of the concentration of nitrites in the nitrates solution as a function of the treatment time expressed in minutes. According to the results of FIG. 14, the concentration of nitrites during the first 25 minutes of treatment increases to reach a maximum concentration of approximately 280 mg / L and then to reach, after 75 minutes of treatment, a reduced concentration of nitrites of 0.5 mg / L. A complementary measurement of the nitrate concentration after 75 minutes of treatment shows a final nitrate concentration of 0 mg / L.
- FIG. 15 represents the evolution of ln (C / Co) as a function of the treatment time expressed in seconds for different masses and forms of zinc, namely powder and shavings, and therefore different contact surfaces.
- the straight line 30 in FIG. 15 corresponds to the use of zinc chips for a contact surface of 0.004 m 2
- the straight line 31 corresponds to the use of zinc powder for a contact surface of 2.07 m 2
- the straight line 32 illustrates the results obtained with zinc powder for a contact surface of 4.14 m 2 .
- the slope of each line represents the product K x S which can be used to determine K provided that the surface can be determined.
- FIG. 20 represents the evolution of the log d [N0 2 ] / dt as a function of the log [N0 2 ] for 2 different pHs, namely a pH of 2 as illustrated by curve 42 and a pH of 3 as illustrated by the curve 43. From this evaluation of the partial order with respect to the protons at low pH, it appears that by increasing the pH, the partial order with respect to the nitrites decreases.
- FIG. 21 illustrates the results obtained under the same experimental conditions as those whose results are represented in FIG. 20, but on which the curve 44 corresponds to a pH of 4 to a pH of 5.
- FIGS. 15 to 22 shows that the more acidic the pH, the faster the reduction but that at the same time, strongly promotes ammonium formation and more acid is consumed.
- the possibility of accelerating the reaction while reducing the formation of this product lies in the use of a larger contact surface when using zinc shavings. While this partial order study highlights key parameters in the reduction reaction, these tests are all performed on solutions made from sodium nitrate and nitrite.
- FIG. 23 illustrates the results obtained in terms of nitrate concentration presented in the form of histograms in which the black bars 46 correspond to the nitrate concentration and the gray bars 47 correspond to the nitrite concentration. It is found that the total reduction of nitrates and nitrites present in the drainage water is reached after 3 hours of treatment.
- FIGS. 24a and 24b show the influence of the treatment temperature on the reduction time of nitrates and nitrites in the drainage water for a pH adjusted every half hour and maintained in this way at a value less than 6 by regular addition of hydrochloric acid.
- the concentrations of nitrates are represented by the respective black bars 48a, 48b and the concentrations of nitrites are represented by the respective gray bars 49a, 49b.
- FIG. 24a corresponds to a temperature of the reaction medium of 20 ° C. and FIG.
- FIG. 24b corresponds to a temperature of the reaction medium 80 ° C.
- an increase in the temperature of the reaction medium makes it possible to reduce the reaction time, the latter having been reduced by approximately 3 hours by working at 80 ° C. with respect to the results obtained at 20 ° C.
- regular adjustment of the pH of the reaction medium remains an important parameter making it possible to reduce the reaction time but also to obtain good reproducibility of the results.
- Figures 25a and 25b highlight the importance of regular adjustment of the pH when reducing nitrates and nitrites in drainage water.
- 25a represents the results obtained in terms of the concentration of nitrates represented by the black bars 50a and in terms of the concentration of nitrites represented by the gray bars 51a, when the temperature of the reaction medium is 20 ° C. and the pH is adjusted to a value less than 6 every quarter of an hour during the first hour of treatment and then every half hour after the first hour of treatment.
- FIG. 25b represents the evolution of the nitrate concentration represented by the black bars 50b and the evolution of the nitrite concentration represented by the gray bars 51b when the temperature of the reaction medium is 80 ° C. for an adjustment of pH identical to that corresponding to the experimental conditions of FIG. 25a.
- FIG. 25a shows the evolution of the nitrite concentration in the drainage water when 15.79 g of zinc shavings are added to a 1 liter solution made up of drainage water for a pH kept constant manually by regular addition of hydrochloric acid 2M and for a stirring speed of 1.37 m / s.
- the device of the invention 55 comprises a first treatment enclosure 56 made of stainless steel with a volume of 40 liters and a useful volume of 36 liters, the lower part of which has a liquid inlet 57 and the upper part of which has a liquid outlet 58.
- a recirculation pump 59 ensures the circulation of the liquid in the enclosure 56 at a flow rate of approximately 600 L / h from the inlet liquid 57 to the liquid outlet 58 from which the liquid circulates in a first conduit 66 to a first three-way valve 65 which allows either to evacuate the treated liquid 68 contained in the enclosure 56 by doing so circulate in a second conduit 69, ie to circulate the liquid in a third conduit 67 to the pump 59. From the pump 59, the liquid then circulates in a fourth conduit 64 to a second three-way valve • 60 then in u n fifth conduit 63 to the liquid inlet 57.
- the enclosure 56 is filled at the start of treatment by circulating the liquid to be treated 61 in a sixth conduit 62 then in the fifth conduit 63 via the second three-way valve 60.
- a zinc layer 70 of a height of approximately 10 cm produced by compression of zinc chips 70a between two perforated plates 71, 72, is arranged transversely in the lower part of the first enclosure 56 over the entire width of the enclosure 56 so that all the liquid circulating in the enclosure passes through the zinc layer 70.
- the agitation of the liquid medium in the enclosure 56 is ensured by an agitator 73 comprising a vertical rod 74 whose rotation is ensured by a motor 75 at which this rod 74 is connected and two stirring mobiles 76,77 secured to the vertical rod 74 and respectively arranged below and above the zinc layer 70 by defining first 78 and second 79 z liquid stirring ones.
- the maximum stirring speed of the agitator 73 in the device of the invention according to the first embodiment is 0.84 m / s.
- the pH of the first stirring zone 78 is controlled by a pH 80 probe passing through the enclosure 56 at the level of the zone 78 and is adjusted by means of pH adjustment 81 making it possible to add hydrochloric acid to 35% by mass in the liquid circulating in the enclosure 56.
- the liquid medium to be treated circulates at least once in the enclosure 56 by passing through the layer of zinc shavings 70a and being subjected to permanent stirring and to pH regulation.
- FIG. 28 illustrates the results obtained in terms of nitrite concentration when a solution of initial nitrate concentration is 2 g / L is treated in the device 55 represented in FIG. 27 with a flow rate of 1500 l / h provided by the pump 59.
- Curve 82 corresponds to a treatment during which the pH is maintained at 2 and in which 6000 g of zinc shavings are used for produce the zinc layer 70.
- Curve 83 corresponds to a treatment in which the pH is maintained at 3 and in which 5000 g of zinc chips are used to produce the zinc layer 70.
- FIG. 29 illustrates the evolution and the concentration of nitrites in the drainage waters of initial concentration of nitrates of 1.99 g / L when these drainage waters circulate in the device of the invention 55 represented in FIG.
- curve 84 corresponds to a pH maintained at 3 for a mass of zinc of 6000 g
- curve 85 corresponds to a pH maintained at 3 for a mass of zinc of 758 g
- curve 86 corresponds to a pH maintained at 3 for a mass of zinc of 1516 g
- the curve 87 corresponds to a pH maintained at 3 for a mass of zinc of 378 g
- the curve 88 corresponds to a pH maintained at 2 for a mass of zinc 6000 g. It appears from these curves that the increase in zinc mass and the decrease in pH make it possible to increase the treatment efficiency.
- the device of the invention makes it possible, from drainage water loaded with approximately 2 g / L of nitrates, to reduce almost all of the nitrates by obtaining a final concentration of nitrates of less than 30 mg / L while completely eliminating the nitrites formed during the reduction reaction of nitrates by zinc.
- Table 3 shows the exchange surface between the zinc and the solution when zinc shavings are used and this compared to the use of zinc powder.
- FIG. 31 represents the device 55 of the invention according to a second embodiment in which the system for entering and leaving the liquid from the enclosure 56 as well as the system for recirculating the liquid in the enclosure 56 involving the liquid inlet 57, liquid outlet 58, the two three-way valves 60, 65 and the pump 59 are identical to those of the device of the invention according to the first embodiment shown in FIG.
- the device represented in FIG. 31 comprises three transverse zinc layers 85a, 85b, 85c with a height less than 10 cm regularly distributed over the entire height of the enclosure 56 so that all of the liquid circulating in the enclosure 56, circulates through the three zinc layers 85a, 85b, 85c which are produced by compression of zinc chips between two respective perforated plates 86a, 86a '; 86b, 86b '; 86c, 86c ', each layer of zinc chips 85a, 85b, 85c having a height of between 7 and 10 cm.
- the stirring of the liquid medium is ensured by the stirrer 73 consisting of the vertical rod 74 connected to the motor 75 which ensures the rotation of the vertical rod and three stirring mobiles 90a, 90b, 90c integral with the vertical rod 74 and respectively arranged in the stirring zones 92a, 92b, 92c respectively located above each zinc layer 85a, 85b, 85c.
- a pH 91 probe is connected to a pump 92 which can inject hydrochloric acid into the conduit 63 which opens onto the liquid inlet 57 by circulating the acid through a conduit 93 and a two-way valve 931 controlled by a control unit not shown connected to the probe 91 and to the pump -92.
- a respective pH probe 93a, 93b and 93c measures the pH and is connected to a housing 94 itself connected to a hydrochloric acid injection pump 95.
- the pump 95 controlled by the housing 94 sends an appropriate quantity of hydrochloric acid through a main conduit 96 and the conduit 97a, 97b and / or 97c connecting the conduit 96 to the stirring zone 92a, 92b, 92c in which the respective pH probe 93a, 93b, 93c detected an increase in pH.
- Each conduit 97a, 97b, 97c has a corresponding two-way valve 94a, 94b, 94c controlled by the housing 94 and allowing the hydrochloric acid circulating in the conduit 97a, 97b, 97c, to be injected into the agitation zone corresponding 92a, 92b, 92c.
- a nitrate detector 98 makes it possible to measure at any time during the treatment the quantity of nitrates present in the upper zone of the enclosure 56 of the device of the invention.
- the first treatment enclosure 56 of the device of the invention according to a third embodiment comprises seven layers of zinc 99a, 99b, 99c, 99d, 99e, 99f, 99g produced in the same way as the zinc layers 85a, 85b, 85c of the device of the invention shown in Figure 31.
- the device shown in Figure 32 has seven corresponding stirring mobiles 100 a, 100 b, 100c, 100 d, 100 e, 100 f , 100 g, respectively placed in each stirring zone 99al, 99bl, 99cl, 99dl, 99el, 99fl, 99gl located above each layer of zinc Corresponding 99a, 99b, 99c, 99d, 99e, 99f, 99g.
- the pH adjustment system in enclosure 56 is identical to that shown in Figure 30 except that the pH probes 93a, 93b, 93c and the respective acid supply lines 97a, 97b, 97c are arranged in every other agitation zone.
- the pH adjustment system at the bottom of the enclosure 56 is not shown in FIG. 32 but can be present and arranged in the same way as on the device represented in FIG. 30.
- the recirculation of the liquid is ensured by the pump 59 the first 66,. third 67, fourth 64 and fifth 63 conduits and the entry of the liquid to be treated 61 into the enclosure 56 is ensured by the sixth conduit 62, the three-way valve 60 and the fifth conduit 63.
- the 32 comprises a liquid outlet 103 independent of the liquid recirculation system which opens into a conduit 105 through which the treated liquid 68 circulates when a two-way valve 104 disposed at the conduit 105 is open, the control of the two-way valve 104 not being shown in FIG. 32.
- the treated liquid 68 may contain a certain amount of zinc in solution resulting from the presence of the zinc chips in the enclosure 56 and from the circulation of the liquid through the zinc layers 99a to 99g.
- the methods and devices of the invention are intended to sanitize a liquid loaded with nitrates without polluting it with other components so that it is not harmful to the environment.
- the device of the invention 55 further comprises a second treatment enclosure 106 connected to the first enclosure 56 by the conduit 105 .
- the second treatment enclosure 106 with a volume of It comprises three cathode electrodes 108a, 108b, 108c and four anode electrodes 109a, 109b, 109c, 109d which are alternately and transversely arranged in the enclosure 106 over the entire width of the enclosure 106 by forming six respective electrolysis cells 110a, 110b, 110c, 110d, 110e, IlOf of the same height and regularly distributed over the entire height of enclosure 106.
- the treated liquid 68 in the first enclosure 56 circulates in the conduit 105 and enters the lower part of the enclosure 107 through a first liquid inlet 111 then flows into the enclosure 106 from the lower part of the enclosure 106 through the six electrolysis cells 110a, 110b, 110c, llOd, 110e, IlOf to the upper part of the enclosure 106 having a liquid outlet 112.
- the circulation of the liquid through the electrolysis cells of the enclosure 107 is ensured by a po mpe with recirculation 113.
- the liquid leaves the enclosure by the outlet 112 and circulates in a conduit 112a via a three-way valve 114, in the conduits 114a and 113a then enters the enclosure 107 again by a second inlet liquid 115 also placed in the lower part of the enclosure 107.
- the liquid can thus circulate several times through the series of electrolysis cells in the enclosure 107 and the flow rate of the pump is approximately 0.5 m / s .
- a pH 120 probe is connected to a housing 121 which controls an injection pump 122 of sodium hydroxide which, when the probe 120 detects a drop in pH, circulates in a conduit 122 opening into the upper part of the enclosure 106.
- the electrode cathode 108b is produced by compression of grains of carbon between two perforated plates 116b, 116b 'in which a perforated metal plate 117 is pressed while being connected to the negative pole of a current generator not shown.
- the anode electrodes 109b, 109c are produced by compression of zinc chips between two perforated plates respectively 118a, 118a '; 118b, 118b 1 and a perforated metal plate 119b, 119c is pressed into the zinc shavings while being connected to the positive pole of the current generator.
- Perforated plates 118a, 118a '; 118b, 118b '; 116b, 116b ' are in the form of a screen making it possible to prevent either carbon grains or zinc chips from being found in the solution.
- the generator delivers a voltage of around 2 Volts for a current between 1.5 and 1.8 Amps per liter of solution.
- the structure of the anode and cathode electrodes described with reference to FIG. 33 apply to all the electrodes shown in FIG. 32.
- Table 4 shows the results in terms of reduction of the zinc concentration in the enclosure 106 as a function of the pH of the solution circulating in the electrolysis cells 110a, 110b, 110c, 110d, 110e, IlOf, the initial concentration of zinc in the liquid 68 and the geometry of the anode electrode.
- the cathode electrode used in the five tests corresponds to that described above with reference to FIGS. 32 and 33.
- the anode electrode mentioned as “plate” in Table 4 consists of a simple perforated zinc plate connected to the generator + pole.
- the anode electrode used and mentioned as “volume” corresponds to that described previously with reference to FIGS. 32 and 33.
- Test n ° 1 was stopped after 90 minutes due to strong odor of chlorine which emanated from enclosure 106, test n ° 2 did not give any convincing result since zinc is found in the form of a deposit at the bottom of enclosure 106 and in the same way for test No. 3, after 5 hours of treatment, a deposit of zinc has formed at the bottom of the enclosure 106.
- test No. 4 in which the initial concentration of zinc in the liquid 68 is 8 g / L allowed, at a pH between 4.5 and 5 and by working with anode and volume cathode electrodes, to arrive at a solution in which the zinc concentration is 3g / L. It was however noticed during this test a modification of the appearance of the zinc chips constituting the anode electrode.
- test No. 5 for an initial zinc concentration of 8 g / L in the liquid 68, a pH between 10 and 10.5 and anode and cathode electrodes conforming to those described with reference to the Figure 33, the final zinc concentration is 15 mg / L after four hours.
- the device 55 of the invention makes it possible, in the first enclosure 56, to considerably reduce the quantity of nitrates present in the drainage water and in the second enclosure 106, which is in series with the first enclosure 56, to eliminate the residual zinc which may remain in solution in the treated solution 68, which very advantageously makes it possible to obtain a solution concentration of nitrates and zinc quite suitable for release to the environment.
- the method and the device of the invention make it possible to reduce the nitrate concentration to a value less than 50 mg / L, this value corresponding to the potability threshold which was set in France, the potability threshold now being set at 25 mg / L.
- the concentration of nitrates obtained by the process and the device of the invention being much less than 50 mg / L, the invention also applies to potability thresholds set at a value less than
- the device of the invention is not limited to the embodiments described above and in particular the device 55 can comprise a multitude of layers of zinc, preferably of limited thickness and in the same way, the device 106 can have a multitude of electrolysis cells.
- the volume of the enclosure 106 can be identical to the volume of the enclosure 56 which advantageously allows the liquid contained in the enclosure 56 to be completely emptied into the enclosure 106.
- the person skilled in the art will adapt an optimum flow rate for the circulation of the liquid for each of these devices.
- the second treatment enclosure 106 although presented as reducing the amount of zinc in the liquid 68 previously treated in the enclosure 56 for reducing nitrates, can be used independently of enclosure 56 to reduce or eliminate, so general, the zinc contained in any liquid medium treated or not previously.
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- Organic Chemistry (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Catalysts (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Electrolytic Production Of Metals (AREA)
Abstract
Description
Claims
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP04791481A EP1670722A1 (fr) | 2003-10-08 | 2004-10-07 | Procede de traitement par voie chimique d un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications |
US10/574,960 US7892439B2 (en) | 2003-10-08 | 2004-10-07 | Method for chemically treating a liquid medium loaded with nitrates, device for treating a liquid medium of this type and applications |
JP2006530420A JP4970942B2 (ja) | 2003-10-08 | 2004-10-07 | 硝酸塩を含む液体培地をその硝酸塩値を低下させるために処理する方法 |
CA2541940A CA2541940C (fr) | 2003-10-08 | 2004-10-07 | Procede de traitement par voie chimique d'un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications |
AU2004280268A AU2004280268B2 (en) | 2003-10-08 | 2004-10-07 | Method for chemically treating a liquid medium loaded with nitrates, device for treating a liquid medium of this type and applications |
HK07102006.1A HK1094791A1 (en) | 2003-10-08 | 2007-02-22 | Method for chemically treating a liquid medium loaded with nitrates, device for treating a liquid medium of this type and applications |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR0311789A FR2860784B1 (fr) | 2003-10-08 | 2003-10-08 | Procede de traitement par voie chimique d'un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications. |
FR0311789 | 2003-10-08 |
Publications (1)
Publication Number | Publication Date |
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WO2005035451A1 true WO2005035451A1 (fr) | 2005-04-21 |
Family
ID=34355331
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR2004/002528 WO2005035451A1 (fr) | 2003-10-08 | 2004-10-07 | Procede de traitement par voie chimique d'un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications |
Country Status (9)
Country | Link |
---|---|
US (1) | US7892439B2 (fr) |
EP (1) | EP1670722A1 (fr) |
JP (1) | JP4970942B2 (fr) |
CN (1) | CN100484885C (fr) |
AU (1) | AU2004280268B2 (fr) |
CA (1) | CA2541940C (fr) |
FR (1) | FR2860784B1 (fr) |
HK (1) | HK1094791A1 (fr) |
WO (1) | WO2005035451A1 (fr) |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2887896A1 (fr) * | 2005-07-04 | 2007-01-05 | Ecole Nale Sup Artes Metiers | Dispositif de production de poudres de fer et de zinc par electrolyse en milieux aqueux heterogenes solide-liquide et leurs applications a la cementation de metaux lourds et a la denitratation |
FR2917734B1 (fr) | 2007-06-19 | 2010-09-10 | Magnes Pierre Jean Maurice | "procede de traitement mixte chimique electrochimique d'un milieu liquide charge en nitrates, dispositif pour traiter un tel milieu liquide et applications" |
CN101746871B (zh) * | 2008-12-08 | 2012-06-20 | 中国地质大学(北京) | 一种电化学去除饮用水源中硝酸盐的方法 |
CN101862646B (zh) * | 2009-04-15 | 2013-05-01 | 中国地质大学(北京) | 一种氨吸附剂再生与再生液无害化处理的方法及装置 |
US11046596B2 (en) | 2012-10-25 | 2021-06-29 | Hydrus Technology Pty. Ltd. | Electrochemical liquid treatment apparatus |
US11046595B2 (en) | 2014-05-23 | 2021-06-29 | Hydrus Technology Pty. Ltd. | Electrochemical treatment methods |
EP3145875B1 (fr) | 2014-05-23 | 2021-09-22 | Hydrus Technology Pty. Ltd. | Procédé de traitement électrochimique |
WO2019104314A1 (fr) * | 2017-11-27 | 2019-05-31 | Chemtreat, Inc. | Procédés et systèmes d'élimination de nitrates pour des applications d'interdiction totale de rejet |
CN109781813A (zh) * | 2019-01-22 | 2019-05-21 | 钟士博 | 一种直接快速检测亚硝酸盐的方法 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5266174A (en) * | 1992-05-12 | 1993-11-30 | Martin Marietta Energy Systems, Inc. | Process for reducing aqueous nitrate to ammonia |
US5951869A (en) * | 1984-04-30 | 1999-09-14 | Kdf Fluid Treatment, Inc. | Method for treating fluids |
US6030520A (en) * | 1997-04-23 | 2000-02-29 | The Regents Of The University Of California | Nitrate reduction |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS4917369A (fr) * | 1972-06-12 | 1974-02-15 | ||
US4283290A (en) * | 1977-07-06 | 1981-08-11 | Davy International (Oil & Chemicals) Ltd. | Purification utilizing liquid membrane with electrostatic coalescence |
JPS5792186A (en) * | 1980-11-29 | 1982-06-08 | Katsuhiro Okubo | Method and device for electrolytic treatment of dilute solution of noble metal salt |
US5093099A (en) * | 1987-11-16 | 1992-03-03 | Kao Corporation | Flaky powder of zinc oxide and its composition for external use |
JP3748960B2 (ja) * | 1996-11-05 | 2006-02-22 | 関西電力株式会社 | 硝酸性窒素含有水の処理方法 |
US7374655B2 (en) * | 2004-01-12 | 2008-05-20 | Novastron | Electrochemical water purifier |
-
2003
- 2003-10-08 FR FR0311789A patent/FR2860784B1/fr not_active Expired - Fee Related
-
2004
- 2004-10-07 AU AU2004280268A patent/AU2004280268B2/en not_active Ceased
- 2004-10-07 US US10/574,960 patent/US7892439B2/en not_active Expired - Fee Related
- 2004-10-07 EP EP04791481A patent/EP1670722A1/fr not_active Ceased
- 2004-10-07 CA CA2541940A patent/CA2541940C/fr not_active Expired - Fee Related
- 2004-10-07 WO PCT/FR2004/002528 patent/WO2005035451A1/fr active Application Filing
- 2004-10-07 CN CNB2004800349873A patent/CN100484885C/zh not_active Expired - Fee Related
- 2004-10-07 JP JP2006530420A patent/JP4970942B2/ja not_active Expired - Fee Related
-
2007
- 2007-02-22 HK HK07102006.1A patent/HK1094791A1/xx not_active IP Right Cessation
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5951869A (en) * | 1984-04-30 | 1999-09-14 | Kdf Fluid Treatment, Inc. | Method for treating fluids |
US5266174A (en) * | 1992-05-12 | 1993-11-30 | Martin Marietta Energy Systems, Inc. | Process for reducing aqueous nitrate to ammonia |
US6030520A (en) * | 1997-04-23 | 2000-02-29 | The Regents Of The University Of California | Nitrate reduction |
Non-Patent Citations (1)
Title |
---|
HUANG C-P ET AL: "Nitrate reduction by metallic iron", WATER RESEARCH, ELSEVIER SCIENCE PUBLISHERS, AMSTERDAM, NL, vol. 32, no. 8, 1 August 1998 (1998-08-01), pages 2257 - 2264, XP004133849, ISSN: 0043-1354 * |
Also Published As
Publication number | Publication date |
---|---|
CA2541940A1 (fr) | 2005-04-21 |
FR2860784A1 (fr) | 2005-04-15 |
FR2860784B1 (fr) | 2007-12-07 |
CA2541940C (fr) | 2013-03-12 |
HK1094791A1 (en) | 2007-04-13 |
AU2004280268B2 (en) | 2010-04-22 |
US7892439B2 (en) | 2011-02-22 |
CN1886346A (zh) | 2006-12-27 |
US20070108134A1 (en) | 2007-05-17 |
JP4970942B2 (ja) | 2012-07-11 |
EP1670722A1 (fr) | 2006-06-21 |
JP2007508130A (ja) | 2007-04-05 |
AU2004280268A1 (en) | 2005-04-21 |
CN100484885C (zh) | 2009-05-06 |
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