Development of a Separate Multiphase Dielectric Barrier Discharge Reactor and Study on the Treatment Effect of Methylene Blue

In order to improve the efficiency of dielectric barrier discharge (DBD) contaminants treatment and reduce the treatment cost, a multiphase DBD plasma water treatment reactor is used in this article. When processing methylene blue solution, the electrode distance is 3 mm, the input voltage is 85 V, and the input frequency is 7.8 kHz. The degradation rate can be maintained at about 90% when the experiment is carried out with different concentrations for 10 min. The energy efficiency value of the solution with different concentrations is continuously rising, and the energy efficiency of the solution with a concentration of 150 mg/L reaches 2091 mg/kW $\cdot \text{h}$ . In experiments under different water volume conditions, the degradation rate of the solution with 300 mL water volume was 74% after the same treatment time 30 min, compared with the degradation rate of 100 mL water volume of 89.3%, but the amount of methylene blue in the degraded solution increased. In the experiment of adjusting the gas volume to 100 ml/min, it is found that when the gas volume increases to 100 ml/min, the degradation rate is 86%, which is 20% higher than 67.3% when the gas input is 60 ml/min.