Influential factors on degradation rate of organic contamination in water treatment by discharge plasma

The paper introduces the research progress and current status of the experimental and theoretical study on degradation rate of organic contamination in the process of treating the waste water by discharge plasma. Based on the existing experimental study, the influential factors on degradation rate of organic contamination by discharge plasma are classified into several aspects, such as the parameters of discharge electrode, those of the pulse power supply, the physics and chemical property of the waste water, the catalysis cooperated with the enhancement effect of the gas-liquid or solid-liquid mixed phases, the initial concentration of the organic contamination, the additive of inorganic salt or hydrogen peroxide and so on. The preliminary mechanisms of the mentioned factors individually acting on degradation rate of organic contamination in experiment are also discussed in detail. The current theoretical study on degradation rate of organic contamination by discharge plasma is summarized from the two aspects: one is the macro-kinetics, the other is micro-kinetics. Meanwhile, the relationship and essence are also analyzed for the further study. Besides, the existing problems which should be resolved exigently in the research of discharge plasma chemical reaction kinetics are presented, such as the solution of the electronic energy distribution function, the study method of non-equilibrium kinetics and nonlinear chemical kinetics, the inclusion of hydrodynamics equations in the current model and so on. Finally, the means of reaction kinetics investigated by use of pulse irradiation technology that has been widely used in the. research of radiation chemistry and the methodology of the orthogonal test that takes into account the interactions of several influential factors are recommended as two promising research methods.