The chemical process of catalytic oxidation is quite simple – the temperature of the exhaust stream is sufficiently elevated to a point in which the chemical bonds that hold the VOC molecules together are broken (oxidized) across the precious metal contained in the catalyst media. The Volatile Organic Compounds (VOCs) contained in the process exhaust stream are converted to carbon dioxide (CO2), water (H2O), and thermal energy. The operating temperature is substantially less than straight thermal oxidation, and when combined with a VOC loading level from the process stream, the system can become self-sustaining (requiring minimal auxiliary fuel to support operation).
A catalyst is a substance that accelerates the rate of the chemical reaction of the volatile organic compound without being consumed. The process of catalytic oxidation operates at a low temperature level that minimizes the formation of NOx. The reduction of the CO2 and minimization of NOx formation are very important, as both of these compounds are regulated as strictly as VOCs by the Environmental Protection Agency (EPA).
A catalytic oxidizer has a relatively quick warm-up time and can run in shorter durations (non-24 hour continuous cycles) without having adverse affects on the overall life of the equipment and its components. In addition, with the relatively low VOC loading, the use of catalytic systems lowers the overall annual operating costs when compared to a direct thermal or thermal recuperative system.
Catalyst cells can be used in direct-fired oxidizers, recuperative oxidizers, or RTOs. Gulf Coast Environmental Systems designs oxidizers to accept various selections of catalyst depending on the application.
Regenerative Catalytic Oxidizer (RCO)
In some applications, the use of Catalyst with the ceramic media helps allow oxidation at reduced temperatures resulting in even lower operating costs compared to a Regenerative Thermal Oxidizer.