Experimental Study On Low-temperature Plasma Technology And Application In Treatment Of Polluted Wastewater Application

Because of the problem of water shortage,treatment of polluted wastewater has become one focus of current concerns of people.With decades of development,people have used different wastewater techniques to polluted wastewater of different characters.However,conventional traditional methods have some drawbacks in instrumentation,cost,maintenance,management,processing and operation.Therefore,people are still exploring and developing new environmentally-friendly and efficient wastewater treatment techniques.Low-temperature plasma is one of advanced oxidation process(AOP)techniques,which has been developed rapidly for application in water treatment in recent years.For this purpose,this dissertation aimed to study application of low-temperature dielectric barrier discharge(DBD)plasma in the treatment the wastewater.By optimizing the design of DBD plasma reactor,the technique of low-temperature plasma in treatment of wastewater was developed.The effects of DBD treatment on methylene blue and antibiotics in water and the corresponding mechanisms were studied.The main results are as follows:1)Participation in the development and optimization of a novel dielectric barrier discharge reactor,calibration of the relationship between discharge power and input power in the case of a single electrode,and study on the electrode expansion performance of the device.The possibility of expansion of the device scale was confirmed and discussed.2)The effects of the new type of dielectric barrier discharge reactor on methylene blue in aqueous solution were studied experimentally.The effects of pH value,initial concentration and volume of the solution on degradation of methylene blue were discussed.The reaction mechanism for the degradation of methylene blue was analyzed.The results may provide guidance for the further improving on the device design.3)The effect of DBD on norfloxacin degradation was studied experimentally.The effect of discharge in different gases on norfloxacin degradation was discussed.The effects of various factors produced in the DBD treatment on the degradation of norfloxacin were analyzed.In the process of plasma discharge,reactive oxygen species(ROS),reactive nitrogen species(RNS),ultraviolet light,and ozone etc.had different degrees of contribution to the degradation of norfloxacin under different conditions.This study may provide guidance for low-temperature plasma treatment of hospital wastewater experimentally and theoretically.