10.11.1 Thermal oxidizer TNV
The simplest technology of thermal oxidation is direct-fired thermal oxidizer. A process stream with hazardous gases is introduced into a firing box through or near the burner and enough residence time is provided to get the desired destruction removal efficiency (DRE) of the VOCs. Most direct-fired thermal oxidizers operate at temperature levels between 980 °C (1,800 °F) and 1,200 °C (2,190 °F) with air flow rates of 0.24 to 24 standard cubic meters per second.
Also called afterburners in the cases where the input gases come from a process where combustion is incomplete, these systems are the least capital intensive, and can be integrated with downstream boilers and heat exchangers to optimize fuel efficiency. Thermal Oxidziers are best applied where there is a very high concentration of VOCs to act as the fuel source (instead of natural gas or oil) for complete combustion at the targeted operating temperature.