A method and system for retrofitting an integrated scrubber to provide maximum oxygen content in a controlled decomposition oxidation (CDO) abatement process. The system includes a thermal/wet integrated scrubber, and a compressed air supply for supplying air to an oxygen separation device that separates the air into a nitrogen-enriched component and an oxygen-enriched component. The oxygen separation device utilizes a ceramic, metallic, carbonaceous or polymeric material to separate from the supplied air an oxygen-enriched component for introduction into the integrated scrubber. The integrated scrubber is equipped with a mechanical scraping device for continuous or intermittent removal of combustion deposits formed during the controlled decomposition oxidation process.