Abstract: The present invention provides a system and method for injecting natural gas in an RTO. The RTO may be, for example, a known type that has a rotary distributor, a center section divided into pie-shaped segments above the rotary distributor, a heat exchanger section above the center section, and a combustion chamber above the heat exchanger. According to an aspect of the invention, the system introduces gas into segments of the center section in a sequenced manner via cycling on/off control valves. In a particular embodiment, the natural gas is injected at a specific location of a respective segment within the center section that is past the rotary distributor seals and directly under the bottom of the heat exchanger bed. According to the injection sequence, the injection of natural gas into the segment commences when the segment begins to receive inlet waste gas streams, and injection ceases before the flow through the sector changes or stops.