Zhaoji Hu

The Effect of Inert Gases on Ozone Generation Using Dielectric Barrier Discharge in Dry Air

This experiment studies the effect of inert gases He, Ar, Kr and Xe on ozone generation within a dielectric barrier discharge reactor fed by dry air. The results show that increasing inert gas content leads to a lower applied voltage, discharge power and reduced field. Although the addition of inert gas would lead to a lower reduced field, however, the electron energy distribution function still shifts to the right. The electron density increases slightly at first and then decreases steadily with increasing Xe content, but it decreases monotonically with increasing content of He, Ar and Kr. With regard to dry air/Kr and air/Xe mixtures, ozone concentration and ozone yield show a slight initial increase, followed by a steady decrease for and , which are favorable for ozone production through the Penning dissociation of O2 due to their lower excitation energy.

The Effect of SF6 on Ozone Generation using Dielectric Barrier Discharge

This paper reports the results of an experimental study of effect of SF6 on ozone generation within a Dielectric Barrier Discharge (DBD) fed by both pure oxygen and dry air. The chemical reaction mechanisms relevant to the process of ozone generation (and destruction) are discussed. The experimental results show the oxygen source should avoid the presence of SF6 but the addition of a small amount of SF6 in an air discharge can improve ozone concentration and ozone produce efficiency.

Experimental Study on Ozone Generation and Ozone Oxidation to Removal Multi-Pollutant of Flue Gas

Experiments were carried out to study the effects of peak voltage and gap width on ozone generated by proper high frequency and high voltage power supply. The results show that the corona inception voltage are 4100 V, 6500 V and 8040 V when the gap width are 1 mm, 2 mm and 3mm, respectively. The highest volume fraction and production efficiency of ozone are 24.55×10-3 and 134 g/kWh with a gap width of 1 mm. The volume fraction of ozone generated is twice than an ozone generator (famous brand in China), while the production efficiency is equal to it. The simultaneous removal of NOx/SO2 by O3 oxidation was investigated by experiment. In the assistance of wet scrubber, the SO2 removal efficiency is nearly 100% and the NOx reduction efficiency is 86.27% at [O3]/[NO]=0.9.

The Influence of Inert Gas Addition on Electric Breakdown Utilizing Dielectric Barrier Discharge in Ozone Generation in Air

This article investigates the effect of inert gas addition He, Ar, Kr, and Xe on gas breakdown voltage within a dielectric barrier discharge reactor with air feed gas. The density-normalized effective ionization coefficients are calculated for inert gas/air mixtures; the critical reduced field is then obtained where the electron ionization exactly balances the attachment. Adding inert gases would lead to the decreasing critical reduced field strength due to the enhancement of effective ionization coefficient. In addition, inert gas additions have shown to reduce the breakdown voltage. Moreover the calculated breakdown voltage values and the experimental data are plotted for the sake of comparison and results show that calculated results are in agreement with the experimental values. Parametric studies offer substantial insight in plasma physics, as well as in ozone generation applications.

Optimal Design for Simultaneous Desulfurization and Denitrification by Ozone Oxidation Integrating with Chemical Scrubber

In order to obtain minimum NOx and SO 2 emissions, extra investment and operating costs needs to be supplied. The cost of the ozone oxidation integrating with chemical scrubber (OO&CS) also increases nonlinearly as emissions decrease. This poses a challenging multiobjective optimization problem where emissions like NOx and SO 2 need to be minimized, while minimizing the system cost. A multi-pollutant oxidation by ozone model and an OO&CS process model incorporating in a multiobjective problem is employed to optimize the OO&CS process. It offers multiple Pareto optimal designs that cover the whole Pareto set in an efficient and uniform way and presents abundant insight information approximately the multiobjective problem. These designs capture the nonlinear nature of the OO&CS process, which can eliminate bad designs and promote designs that have lower emissions and lower cost. The optimal process is a valuable tool for design engineers for redesigning the best available design system to make it cost efficient while keeping its advantage of very low level of all pollutant emissions.