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Partager le résultat de cette recherche Interroger des sources externesContribution a l'étude des procèdes électrochimiques d'adoucissement des eaux dures / Yasmina Boulahèib (Née Bendaoud)
Titre : Contribution a l'étude des procèdes électrochimiques d'adoucissement des eaux dures Type de document : texte imprimé Auteurs : Yasmina Boulahèib (Née Bendaoud), Auteur ; Samira Ghizellaoui, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 187 f. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Entartrage traitement chimique PCR chronoampérométrie impédancemétrie MEB KH2PO4 Polyphosphates HEDP Scaling chemical treatment chronoamperometry impedance SEM ???? ?????? ???????? ?????? ??????? ?????? ?????????????????? ?????? ????????? ???????? ????? Index. décimale : 540 Chimie et sciences connexes Résumé : Treating hard water has been interest from several works in order to reduce the adverse consequences of tartar. Hard water deposits form compact and adherent to the walls of pipes and industrial or domestic installations (GHIZELLAOUI, 2006).
Our study focuses on softening hard water Hamma having a hardness of 59°F and Negrine with a hardness of 56°F in the presence of KH2PO4, polyphosphates and HEDP.
The evaluation and the inhibition of scaling of hard waters of Hamma and Negrine were carried out by using four methods:
- The chemical method for evaluating the effective concentration of inhibitor to reduce the hardness of waters of Hamma and Negrine at temperature sources 30°C while maintaining a residual calcium concentration of 1 00 mg/L.
- The method of rapid precipitation controlled to track the phenomenon of germination growth during the formation of the deposit of calcium carbonate.
- The electrochemical method of accelerated scaling to assess the scaling power of raw waters of Hamma and Negrine by electrochemical way and in the presence of chemical inhibitors (KH2PO4, polyphosphates and HEDP );
- electrochemical method for measuring impedances of precipitated deposits metal deposit calcium carbonate
- electrolyte interface enables an overall assessment by means of the highfrequency resistance , adhesion and the importance of filing carbonate calcium ( Khalil et al.1993).
-The effect of inhibitors on the morphology and adhesion of the deposit of calcium carbonate was observed by the scanning electron microscope SEM and RX.
The application of chemical treatment of the waters of Hamma and Negrine at temperature of 30°C showed that partial inhibition of hardness requires addition of 2 mg/L of KH2PO4 for Hamma and 3 mg/L for Negrine. By against, the use of the polyphosphates inhibits scaling at a concentration of 10 mg/L for Hamma water and 5 mg/L for Negrine water.
The HEDP effect is at a concentration of 1 00 mg/L for Hamma and 50 mg/L for Negrine.
These values are reduced using the method of rapid controlled precipitation for each of the three inhibitors (0.1 mg/L KH2PO4, 0.01 mg/L Polyphosphates or 0.01 mg/L HEDP) for water of Hamma, and (0.5 mg/L KH2PO4, 1 mg/L Polyphosphates or 0.01 mg/L HEDP ) for water of Negrine.
The chronoamperometric study shows that the scaling time increases with the addition of (0.1 mg/L KH2PO4, 0.04 mg/L Polyphosphates or 0.005 mg/L HEDP ) for Hamma water and (0.5 mg/L KH2PO4, 0.25 mg/L Polyphosphtes or 10-5 mg/L HEDP) for Negrine water.
The impedance measurement obtained from the raw waters of Hamma and Negrine compared to treated waters shows a decrease in the amount of calcium carbonate scale as well as its adhesion by measuring high frequency resistors deposits from addition of (0.01 mg/L KH2PO4, 0.01 mg/L Polyphosphates or 0.005 mg/L HEDP) for Hamma also (0.5 mg/L KH2PO4, 0.05 mg/L Polyphosphates or 0.0075 mg/L HEDP) for Negrine.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/BOU6778.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9831 Contribution a l'étude des procèdes électrochimiques d'adoucissement des eaux dures [texte imprimé] / Yasmina Boulahèib (Née Bendaoud), Auteur ; Samira Ghizellaoui, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 187 f.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Entartrage traitement chimique PCR chronoampérométrie impédancemétrie MEB KH2PO4 Polyphosphates HEDP Scaling chemical treatment chronoamperometry impedance SEM ???? ?????? ???????? ?????? ??????? ?????? ?????????????????? ?????? ????????? ???????? ????? Index. décimale : 540 Chimie et sciences connexes Résumé : Treating hard water has been interest from several works in order to reduce the adverse consequences of tartar. Hard water deposits form compact and adherent to the walls of pipes and industrial or domestic installations (GHIZELLAOUI, 2006).
Our study focuses on softening hard water Hamma having a hardness of 59°F and Negrine with a hardness of 56°F in the presence of KH2PO4, polyphosphates and HEDP.
The evaluation and the inhibition of scaling of hard waters of Hamma and Negrine were carried out by using four methods:
- The chemical method for evaluating the effective concentration of inhibitor to reduce the hardness of waters of Hamma and Negrine at temperature sources 30°C while maintaining a residual calcium concentration of 1 00 mg/L.
- The method of rapid precipitation controlled to track the phenomenon of germination growth during the formation of the deposit of calcium carbonate.
- The electrochemical method of accelerated scaling to assess the scaling power of raw waters of Hamma and Negrine by electrochemical way and in the presence of chemical inhibitors (KH2PO4, polyphosphates and HEDP );
- electrochemical method for measuring impedances of precipitated deposits metal deposit calcium carbonate
- electrolyte interface enables an overall assessment by means of the highfrequency resistance , adhesion and the importance of filing carbonate calcium ( Khalil et al.1993).
-The effect of inhibitors on the morphology and adhesion of the deposit of calcium carbonate was observed by the scanning electron microscope SEM and RX.
The application of chemical treatment of the waters of Hamma and Negrine at temperature of 30°C showed that partial inhibition of hardness requires addition of 2 mg/L of KH2PO4 for Hamma and 3 mg/L for Negrine. By against, the use of the polyphosphates inhibits scaling at a concentration of 10 mg/L for Hamma water and 5 mg/L for Negrine water.
The HEDP effect is at a concentration of 1 00 mg/L for Hamma and 50 mg/L for Negrine.
These values are reduced using the method of rapid controlled precipitation for each of the three inhibitors (0.1 mg/L KH2PO4, 0.01 mg/L Polyphosphates or 0.01 mg/L HEDP) for water of Hamma, and (0.5 mg/L KH2PO4, 1 mg/L Polyphosphates or 0.01 mg/L HEDP ) for water of Negrine.
The chronoamperometric study shows that the scaling time increases with the addition of (0.1 mg/L KH2PO4, 0.04 mg/L Polyphosphates or 0.005 mg/L HEDP ) for Hamma water and (0.5 mg/L KH2PO4, 0.25 mg/L Polyphosphtes or 10-5 mg/L HEDP) for Negrine water.
The impedance measurement obtained from the raw waters of Hamma and Negrine compared to treated waters shows a decrease in the amount of calcium carbonate scale as well as its adhesion by measuring high frequency resistors deposits from addition of (0.01 mg/L KH2PO4, 0.01 mg/L Polyphosphates or 0.005 mg/L HEDP) for Hamma also (0.5 mg/L KH2PO4, 0.05 mg/L Polyphosphates or 0.0075 mg/L HEDP) for Negrine.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/BOU6778.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9831 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/6778 BOU/6778 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude des méthodes d'évaluation et d'inhibition du pouvoir incrustant des eaux dures Type de document : texte imprimé Auteurs : Hadda Semine ras, Auteur ; Samira Ghizellaoui, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 218 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Entartrage CaCO3 inhibition K2HPO4 K 3PO4 tripolyphosphates (STTP) chronoampérométrie chronoélectrogravimétrie impédancemétrie PCR RX Raman Scaling K3PO4 chroamperometry chronoelectrogravimetry impedancemetry FCP ???? ??????? ????????? ????? STTP K2HPO4????????????????
?????????????? ???????? ?????????????? ??????? ?????? ??????? ?????? ??????? ??? ?????Index. décimale : 540 Chimie et sciences connexes Résumé : The precipitation of an insulating layer of calcium carbonate on the walls of the water distribution of Hamma and Fourchi have serious consequences technique and economic , reduced heat transfer in heat exchangers, limit the efficiency of these devices (valves and taps) by decreasing the flow rate in the pipes.
The objective of this study is the inhibition of the scaling capacity of domestic and industrial hard water for Hamma and Fourchi in the presence of K2HPO4 and K3PO4 and STTP. Various processes (electrochemical and chemical) are used.
The study of the evaluation of the encrusting power of its waters was carried out by means of chronoamperometry which is based on the reduction of dissolved oxygen and showed that these waters are very scaling. To combat hard water scaling, we have shown that it is sufficient to add low concentrations of inhibitors (K2HPO4, K3PO4, Polyphosphates) in order to obtain a total inhibition of the precipitation of the calcium carbonate.
It is possible to determine by the chronoelectrogravimetric (depending on the mass of the calcium carbonate as a function of time) the amount of inhibitor to be added in order to obtain the total inhibition of the calcium carbonate deposition. K2HPO4, K3PO4 and tripolyphosphates (STTP) appear as inhibitors particularly well suited to hard waters.
Electrochemical Impedance Spectroscopy (EIS) is used to characterize the adhesion and compactness of calcium carbonate deposition on a metal surface by measuring the high frequency resistance (Rhf) and the high frequency capacitance (Chf).
The addition of the three inhibitors (K2HPO4, K3PO4 and tripolyphosphates STTP) resulted in a decrease in high frequency resistance and the high frequency capacity increased. This reflects the porous nature of the deposit and the effectiveness of the scaling inhibitors K2HPO4 and K3PO4 and tripolyphosphates STTP.
The Fast Controlled Precipitation test (FCP) developed by LEDION et al. (1997), in the presence of K2HPO4, K3PO4 and tripolyphosphate (STTP) at low concentrations, delayed precipitation of calcium carbonate.
The analysis of calcium carbonate deposition by (RX, Raman) changes the morphology of calcite in raw water to a mixture of (calcite, vaterite and aragonite). Among the inhibitors studied, STTP remains the best inhibitor because it acts at a very low concentration by blocking the (germination-growth) of calcium carbonate.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/SEM7263.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10860 Etude des méthodes d'évaluation et d'inhibition du pouvoir incrustant des eaux dures [texte imprimé] / Hadda Semine ras, Auteur ; Samira Ghizellaoui, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 218 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Entartrage CaCO3 inhibition K2HPO4 K 3PO4 tripolyphosphates (STTP) chronoampérométrie chronoélectrogravimétrie impédancemétrie PCR RX Raman Scaling K3PO4 chroamperometry chronoelectrogravimetry impedancemetry FCP ???? ??????? ????????? ????? STTP K2HPO4????????????????
?????????????? ???????? ?????????????? ??????? ?????? ??????? ?????? ??????? ??? ?????Index. décimale : 540 Chimie et sciences connexes Résumé : The precipitation of an insulating layer of calcium carbonate on the walls of the water distribution of Hamma and Fourchi have serious consequences technique and economic , reduced heat transfer in heat exchangers, limit the efficiency of these devices (valves and taps) by decreasing the flow rate in the pipes.
The objective of this study is the inhibition of the scaling capacity of domestic and industrial hard water for Hamma and Fourchi in the presence of K2HPO4 and K3PO4 and STTP. Various processes (electrochemical and chemical) are used.
The study of the evaluation of the encrusting power of its waters was carried out by means of chronoamperometry which is based on the reduction of dissolved oxygen and showed that these waters are very scaling. To combat hard water scaling, we have shown that it is sufficient to add low concentrations of inhibitors (K2HPO4, K3PO4, Polyphosphates) in order to obtain a total inhibition of the precipitation of the calcium carbonate.
It is possible to determine by the chronoelectrogravimetric (depending on the mass of the calcium carbonate as a function of time) the amount of inhibitor to be added in order to obtain the total inhibition of the calcium carbonate deposition. K2HPO4, K3PO4 and tripolyphosphates (STTP) appear as inhibitors particularly well suited to hard waters.
Electrochemical Impedance Spectroscopy (EIS) is used to characterize the adhesion and compactness of calcium carbonate deposition on a metal surface by measuring the high frequency resistance (Rhf) and the high frequency capacitance (Chf).
The addition of the three inhibitors (K2HPO4, K3PO4 and tripolyphosphates STTP) resulted in a decrease in high frequency resistance and the high frequency capacity increased. This reflects the porous nature of the deposit and the effectiveness of the scaling inhibitors K2HPO4 and K3PO4 and tripolyphosphates STTP.
The Fast Controlled Precipitation test (FCP) developed by LEDION et al. (1997), in the presence of K2HPO4, K3PO4 and tripolyphosphate (STTP) at low concentrations, delayed precipitation of calcium carbonate.
The analysis of calcium carbonate deposition by (RX, Raman) changes the morphology of calcite in raw water to a mixture of (calcite, vaterite and aragonite). Among the inhibitors studied, STTP remains the best inhibitor because it acts at a very low concentration by blocking the (germination-growth) of calcium carbonate.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/SEM7263.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10860 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité SEM/7263 SEM/7263 Thèse Bibliothèque principale Thèses Disponible
