Exhaust gas treatment, also known as exhaust gas purification, refers to the pre-treatment of exhaust gas generated in industrial sites and factory workshops before external discharge, in order to meet the national standards for external emissions of exhaust gas.

Catalytic combustion is a method similar to thermal oxidation to treat VOCs. It purifies organic matter by using precious metal catalysts such as platinum and palladium, as well as transition metal oxide catalysts, instead of flames. The operating temperature is half lower than that of thermal oxidation, usually between 250 ℃ and 500 ℃. Due to the decrease in temperature, standard materials are allowed to replace expensive special materials, greatly reducing equipment and operating costs. Similar to thermal oxidation, the system can still be divided into two types of heat recovery methods: interstitial catalytic combustion and regenerative catalytic combustion.

Intermittent wall catalytic combustion (TR0) is a heat exchanger installed behind the catalytic bed. This heat exchanger not only reduces the temperature of the exhaust gas, but also preheats VOC containing organic waste gas for treatment. Its heat recovery reaches 60% to 75%. This type of oxidizer has long been used in industrial processes.

Regenerative catalytic combustion (RCO) is a new catalytic technology. It has the characteristics of efficient RTO energy recovery and the advantages of low-temperature operation and energy efficiency in catalytic reactions. The catalyst is placed on top of the thermal storage material to achieve optimal purification, with a heat recovery rate of up to 95% to 98%. The key to the performance of the RCO system is the use of specialized catalysts, such as precious or transition metal catalysts impregnated on saddle shaped or honeycomb shaped ceramics, which allow oxidation to occur at half the temperature of the RTO system, reducing fuel consumption and equipment cost.

Some countries have started using RCO technology for the elimination of organic waste gas, and many RTO equipment has begun to transform into RCO, which can reduce operating costs by 33% to 75% and increase exhaust gas flow by 20% to 40%.