Abstract:Aiming to determine the process parameters for electrocoagulation treating high fluorine groundwater and its de-fluorine kinetics, the electrocoagulation with bipolar aluminum electrodes was used to treat high fluorine groundwater and study its de-fluorine process and kinetic model. The effects of current density, pH, electrode distance and initial fluorine concentration on the de-fluorine process by electrocoagulation were also investigated, respectively. The results showed that the electrocoagulation de-fluorine process followed the first-order kinetics model. The theoretical time of de-fluorine depended on the initial fluorine concentration and the kinetic constant, while the kinetic constant of de-fluorine was affected by current density, electrode distance and initial fluorine concentration. The highest fluorine removal efficiency by electrocoagulation with bipolar aluminum electrodes reached 89.56% with energy consumption of 0.157 8 kWh·g?1 when the operational parameters of current density, pH and electrode distance maintained at 300 A·m?3, 6.0~7.0 and 10 mm, respectively. However, the aluminum-fluorine ratio decreased with the increase of the initial fluorine concentration, resulting in a decrease in the fluorine removal efficiency, which was not conducive to de-fluorine by electrocoagulation. This research provides a theoretical basis for the practical application of electrocoagulation treating high fluorine groundwater and the development of de-fluorine reactor. Key words:bipolar aluminum electrodes/ electrocoagulation/ current density/ kinetics/ fluorine-containing groundwater.
图1电絮凝装置示意图 Figure1.Schematic diagram of the electrocoagulation setup
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CNOOC Tianjin Chemical Research and Design Institute Co. Ltd., Tianjin 300131, China Received Date: 2019-07-30 Accepted Date: 2019-10-23 Available Online: 2020-05-12 Keywords:bipolar aluminum electrodes/ electrocoagulation/ current density/ kinetics/ fluorine-containing groundwater Abstract:Aiming to determine the process parameters for electrocoagulation treating high fluorine groundwater and its de-fluorine kinetics, the electrocoagulation with bipolar aluminum electrodes was used to treat high fluorine groundwater and study its de-fluorine process and kinetic model. The effects of current density, pH, electrode distance and initial fluorine concentration on the de-fluorine process by electrocoagulation were also investigated, respectively. The results showed that the electrocoagulation de-fluorine process followed the first-order kinetics model. The theoretical time of de-fluorine depended on the initial fluorine concentration and the kinetic constant, while the kinetic constant of de-fluorine was affected by current density, electrode distance and initial fluorine concentration. The highest fluorine removal efficiency by electrocoagulation with bipolar aluminum electrodes reached 89.56% with energy consumption of 0.157 8 kWh·g?1 when the operational parameters of current density, pH and electrode distance maintained at 300 A·m?3, 6.0~7.0 and 10 mm, respectively. However, the aluminum-fluorine ratio decreased with the increase of the initial fluorine concentration, resulting in a decrease in the fluorine removal efficiency, which was not conducive to de-fluorine by electrocoagulation. This research provides a theoretical basis for the practical application of electrocoagulation treating high fluorine groundwater and the development of de-fluorine reactor.