Dielectric barrier discharge (DBD) is the most efficient way used in industry for ozone generation. In last decades, many papers were published on such DBD-based ozone generators. Several geometric configurations can be used to generate ozone. They can be classified into two types depending on the discharge form: volume DBD, which is the common one in ozone industry, and surface DBD. Many studies have been conducted to analyze the ozone generation efficiency of both reactors to get maximum ozone production with the lowest possible power consumption. The aim of this paper is to carry out an experimental analysis of a patent-pending new reactor, of hybrid configuration, in which occur simultaneously a volume and a surface DBD. The hybrid reactor comprises a ground stainless steel cylindrical electrode, within which is placed a glass tube separated by an interval of 1 mm in which the volume DBD occurs. A second mesh stainless steel electrode connected to the high voltage is placed inside the glass tube wherein the surface discharge occurs. The obtained results showed a clear superiority of the hybrid reactor compared to both volume and surface DBD, in terms of the ozone concentration. The difference in the ozone concentration reaches up to 50% compared to the volume DBD and 30% compared to the surface DBD.

Ozone generation by dielectric barrier discharge (DBD) is widely used in industry. Several DBD configurations can be used to generate ozone, which are classified in two main types depending on the geometry of the electrodes: volume DBD and surface DBD models. The aim of this work is to conduct a comparative experimental analysis between surface DBD and volume DBD ozone generators having a cylindrical geometry. This comparative investigation is carried out not only in terms of ozone concentration and energy efficiency, but also in terms of cooling performance. Two experimental setups were used in this work, one for measuring the ozone concentration (in mg/L) and the ozone rate production (in g/h) and a second for cooling experiments. The obtained results show that although the volume DBD model is the most frequently used in industry, the surface DBD reactor gives better results in terms of ozone rate production and cooling.

The aim of this paper is to evaluate the collection efficiency of submicron particles using electrically charged nonwoven filter media. A triode-type electrode arrangement consisting of a high-voltage wire-type ionizing electrode, a metallic grid, and grounded plate electrode is employed to control the distribution of electric charges deposited on the media. Surface electric potential measurement is carried out to study the evolution in time and the repartition in space of deposited charges. The collection efficiency is estimated by measuring the particle concentrations downstream and upstream of the charged filter media. The main results show good correlation between the surface potential level and the collection efficiency of submicron particles for several charging conditions. In particular, filtration performance increases with increasing the corona current through the media during the charging process. Increasing the electric field between the grid and the media during corona charging has also a positive effect on the collection efficiency. Results indicate that high collection performances could not be achieved using thin monolayer media.

This experimental work is aimed at evaluating the effects of high voltage waveform (modified square waveform) on the collection efficiency of a wire-to-square tube electrostatic precipitator using dielectric barrier discharge. The experiments are performed with incense smoke particles having a mean size of about 0.32 μm. An aerosol spectrometer is employed for characterizing the size distribution of these particles at the outlet of the electrostatic precipitator. The collection efficiency is estimated for various applied voltages (ranges: 4 to 20 kV) at fixed frequency (100 Hz) and flow rate (10 L.min^-1). The input parameters under study are the pulse duration, the rise and fall times, the presence of an Offset, and the plateau of the high voltage. The experimental results show that the square waveform with modified plateau is able to increase the performance of the electrostatic precipitation.