Gaseous pollutant destruction apparatus and method using self-resonant corona discharge

摘要

A pollutant destruction system connects a capacitive corona discharge chamber (2; 60; 68a, 68b; 72a, 72b, 72c) in a self-resonant circuit with an inductive element (16; 66; 70; 74). Intermittent energizing signals (34, 34', 40, 50) are furnished from a power supply (18, 20, 22) to induce corona discharges (54) within the chamber, with the resonant circuit responding to the energizing signals by initiating additional corona discharges between energizing signals (34, 34', 40, 50) in a highly energy efficient operation. One or more discharge chambers (2; 60; 68a, 68b; 72a, 72b, 72c) can be provided in the resonant circuit, with each discharge chamber comprising a dielectric enclosure (4) with a distributed electrode (6; 66) outside and an elongate electrode (8; 58; 62) inside the enclosure. The inner electrode (8; 58; 62) can extend either along the chamber axis, or along the inner chamber wall for better support and heat dissipation. The energizing pulse frequency can be controlled in various ways, such as in response to a termination of corona discharges (54), an increase in the pollutant concentration or an acceleration of an engine (28) whose exhaust is being treated, or the pulses can be applied at a fixed rate.