Regenerative thermal oxidizer with inlet/outlet crossover duct

Abstract

A regenerative thermal oxidizer for removing pollutants from industrial exhaust gas flows by high temperature oxidation is composed of at least two regenerative units having a modular construction and a much more compact design than previously achieved in units of comparable size. The more compact design is achieved without any sacrifice in thermal efficiency by providing a regenerative bed having one hot-face area and two cold-face areas connected by an inlet/outlet crossover duct. The bed has 'w'-shaped cross-section to support and contain interlocking heat-exchange elements without the use of hot-face or cold-face area retaining members. Each unit has inlet and outlet flow dividing mechanisms, an inlet duct, and an outlet duct. The inlet duct contains the inlet flow dividing mechanism and communicates with an inlet manifold and the cold-face areas for conducting process gas to the cold-face areas during inlet mode. The outlet duct contains the outlet flow dividing mechanism and communicates with an outlet manifold and the cold-face areas for conducting oxidized air flowing away from the purification chamber to the cold-face areas during outlet mode. The crossover duct forms part of the inlet duct during inlet mode and part of the outlet duct during outlet mode. The design of the crossover duct produces a small flushing volume and may include a flushing valve disposed intermediate the crossover duct for introducing a flushing volume of air through the bed via two separate flow paths.