WASTE GAS TREATING DEVICE

摘要

PURPOSE:To enable driving by low electric power and lower dielectric breakdown strength for a discharge tube having large discharge tube gap. CONSTITUTION:This device is provided with a control part 12 converting a direct power source 11 to an alternate current and varying its voltage and a plasma discharge tube 14 treating NOx, etc., in the waste gas. The control part 12 is composed of a boosting type chopper circuit 21, a driving circuit 22, FETs 23 and 24 for high speed switching and its driving circuits 25 and 26 and CPU 28 controlling each driving circuit. At the device, the primary side voltage of a transformer 13 is boosted by the chopper circuit and the secondary side voltage is set at 20KV being the discharge starting voltage of the plasma discharge tube 14 during at least one period of a plasma discharge starting time. After that, the chopper circuit 21 is drived usually so that the secondary side voltage is 10KV being a discharge maintaining voltage.