Recuperative Thermal Oxidizers
Description of Operation
The Thermal Oxidizer (TO) converts Volatile Organic Compounds (VOCs) and Hazardous Air Pollutants (HAPs) to carbon dioxide and water vapor through thermal oxidation. When required, the TO is provided with a heat exchanger designed to recover thermal energy from the oxidation process.
Exhaust gas containing VOC and HAP compounds from the process is directed through the inlet isolation damper, exhaust fan, and directed to the inlet side of the heat exchanger. As the gas passes though the cool side of the heat exchanger, it gradually increases in temperature until is it near the combustion chamber temperature. As the gas exits the heat exchanger, it passes through the combustion chamber where the gas is increased and held at a preset temperature (usually 1,400°F). The combustion chamber is designed to hold the contaminants for at least one-second to insure total conversion occurred. A burner will add heat, if required, to maintain set-point temperature at the discharge of the heat exchanger.
The newly purified exhaust gas exits the oxidation chamber and enters the hot side of the heat exchanger. Similar to the inlet side, the exhaust gas passes through the hot side of the heat exchanger, but this time, it gradually decreases in temperature until it is very close to the inlet temperature (within 250°F on a 83% thermal energy recovery system). The cleaned exhaust gas is then directed to the exhaust stack and discharged to atmosphere.
Sample Installation of a Recuperative Thermal Oxidizer
