Facts at your Fingertips: Thermal Oxidizer Selection

Thermal oxidizers are pollution-control units designed to prevent process-generated volatile organic compounds (VOCs) from entering the environment. Different technologies offer tradeoffs among initial cost, operating expense, complexity, emissions, fuel efficiency and destruction efficiency. This one-page reference provides information on selecting thermal oxidizers. Thermal oxidizer designs vary widely, but can be generally split into three main categories: direct-fired, regenerative and catalytic. A thermal oxidizer sustains the proper conditions for oxidization of the combustible materials in three ways: by maintaining an operating temperature sufficiently above the autoignition point of the gas, by providing enough time for combustion and by introducing excess oxygen to complete the oxidation reactions. Direct-fired thermal oxidizers Direct-fired thermal oxidizers use a burner to heat a chamber to proper oxidation temperatures for the required destruction efficiency. The chamber must be designed to maintain an adequate residence time and provide sufficient velocity for turbulent mixing. If the process gas has sufficient heat content, it can be used as the fuel gas for the burner. Otherwise, supplemental fuel is required. A…