Abstract: A pilotless flare ignitor which is capable of igniting waste gas issuing continually or sporatically from a flare stack and may include an ignitor housing having an open end which extends into the flare stack. At least two pairs of electrodes are mounted in the ignitor housing, and the electrodes of each electrode pair are positioned to define a spark gap for producing a spark in the ignitor housing. A timer controls the duration of the spark and repeatedly and continually alternates the spark among the multiple electrode pairs. As the gas continually or intermittently and sporadically flows upwardly through the flare stack and into the ignitor housing, the spark, alternating between the electrodes of the multiple electrode pairs, is continually present in the ignitor housing to ignite the waste gas in the ignitor housing and flare stack.

Abstract: A pilotless flare ignitor for igniting waste gas issuing from a flare stack, characterized by an ignitor housing including a horizontal ignitor head having an open end which extends into the flare stack. A pair of electrodes are mounted horizontally in the ignitor head and the ends of the electrodes are positioned to define a diagonal spark gap for producing a spark in the ignitor head. A step-up transformer is wired to the electrodes for generating the spark in the spark gap and a timer, wired to the transformer, controls the duration of the spark. As the gas flows upwardly through the flare stack and into the open end of the ignitor head, the timer is operated to periodically energize the transformer and produce a spark between the electrodes in order to intermittently ignite the waste gas in the ignitor head and flare stack.