Dielectric Barrier Discharge Arrangement for Air Disinfection

Plasma arrangements are widely used for disinfection purposes. Dangerous microorganisms and microbes should be destructed in plasma region due to summary effect of produced ozone, irradiation of hard UV and generated active species. Dielectric barrier discharges (DBD) develop with sufficiently high electrical field in the gas area of an arrangement with at least one insulation barrier between two electrodes. DBD plasma exists in the form of numerous temporally non-stationary, locally filamentary micro discharges. DBD arrangement at the air by atmospheric pressure presents a low-cost alternative to conventional plasma reactors. Grid DBD arrangement consists of some warp thread electrodes, which are weaved together with weft thread ones. As power supply for the barrier arrangement serves a pulse generator, which supplies the arrangement with sinusoidal pulse trains or continuous alternating voltages. This generator functions resonance-dependently in a frequency range from 10 kHz to 60 kHz. The light appearances of barrier discharges are investigated with the help of a CCD high-speed camera. The wire fabric shows a stable plasma generation in all stitchers, the cross points of the wires. For the optimisation of the plasma generation the different electrical parameters can be varied in wide range, to these parameters belong the pulse duration, the frequency of the generator as well as the pulse to pulse time. Dissipated energy of discharges rises from 5 μJ up to 100 μJ per period in the applied voltage range of 200 – 500 V using sine voltage of 60 kHz. Investigated Grid DBD shows a stable operation in wide range of applied voltage. Such a wire fabric enables the generation of plasma-active species at one atmosphere. Due to inherited properties of DBD a disinfection function of the wire fabric for air cleaning should be realised