| Because of its strong oxidation characteristics of ozone, it was widely used in oxidation decomposition of refractory pollutants and disinfection, but in the practical application, its mass transfer efficiency in the liquid phase is low, limiting the wide application of ozone technology. The new method for enhancement of mass transfer in 03/H20 contactor with electric field was put forward, and made the experimental study. Bubble behavior characteristics in the gas/liquid two-phase system caused by a non-uniform electric field was studied, through the finite element method. Explained the mechanism of electric field enhanced mass transfer; The effect of the power parameters,the discharger characteristic parameters and the wastewater physical properties on mass transfer efficiency was investigated. Gram-negative bacteria Escherichia coli, Acinetobacter were selected as a model organism to study the sterilization effect of high-concentration ozone water, and obtained its dose-effect relationship and the dynamic model. The main conclusions are as follows:1) electric field strength on both sides of the bubble level has increased electric field strength at the top and bottom has decreased, with the Non-uniform electric field; Electric field strength at the top and bottom was not symmetrical distribution; it reaches a minimum 167.74KV/m at the top; along the outside top of the bubble surface normal direction, the maximum gradient field strength was got; Field strength inside the bubble is not zero, it increased about 50% higher than that of the state without electric field.2) With the Non-uniform electric field, The surface was not uniformly spherical bubble due to the uneven distribution of electrical stress, but was elongated along the direction parallel with the electric field, eventually become a prolate ellipsoid; And with the field strength increases, the bubble deformation increased, When the deformation reaches a certain degree, ultra-fine bubble air bubbles breaking instability.3) With the increase of pulse voltage, ozone concentration in water and the total mass transfer coefficient increased correspondingly, ozone off-gas concentration reduced. When the voltage is 2 kV, ozone concentration in water quality increased by 43.1%, the total mass transfer increased by 89.11% higher than that of the state without electric field.4) within the electrodes distance range of 3-7 cm, ozone concentration in water and the total mass transfer coefficient increased correspondingly, ozone off-gas concentration reduced.; The best mass transfer was got, under the electrode distance of 3cm, The worst mass transfer was got, under the electrode distance of 1cm;Less air flow rate can improve mass transfer. Ozone mass transfer under the flow of 60ml/min effects is better than the flow of 100ml/min.5) High concentration ozone water has high efficacy in killing the selected model organisms (E. coli, Acinetobacter); As the applied ozone water dose (concentration) increased the inactivation rate of model organisms increased significantly; 1 ml of E. coli bacteria liquid(10~6 CFU/ml) can be Completely killed, with 2500μL ozone water; 1ml of Acinetobacter bacteria liquid(10~6 CFU/ml) can be Completely killed, with 1750μL ozone water; And the lasting effect of killing bacteria, no bacteria regeneration were got.6) E.Coli had stronger resistance to High concentration ozone water than Acinetobacter, and the inactivation rate were 0.192 min-1 and 0.2799 min-1 separately; The first order reaction dynamic model of Chick Model could embody the inactivation feature of E. Coli, Acinetobacter, the conclusion agree with experimental results。The proposed method that electric field enhances ozone mass transfer is potential for a propagation industry application because of its advantages, such as, sufficient contact reaction, high dissolution speed, high ozone gas utilization rate, high mass transfer efficiency, low energy consumption, simple operation, easy maintenance. And it will promote the application of ozone technology.
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