An automobile manufacturer installed a regenerative thermal oxidizer in its paint shop for the control of volatile organic compounds.

Designed and built by Catalytic Products International (CPI), Lake Zurich, Ill., the 50,000-scfm oxidizer replaces existing fluidized-bed concentrators. The roof-mounted RTO will control VOC emissions from four spray coating lines with 98 percent destruction rate efficiency, according to CPI, which would allow the facility to maintain compliance with Clean Air Act standards. The oxidizer provides a thermal efficiency of 95 percent, according to the manufacturer, while allowing for minimal gas consumption and operating costs.

In this application, the exhaust from the spray coating lines contains VOCs such as siloxanes. When oxidized, the siloxanes present in the solvents form silicon dioxide (SiO₂), an inorganic particulate, which clings to hot, metallic surfaces and forms a destructive barrier layer in the exhaust system and thermal oxidizer. The RTO includes a special media design to handle the light particulate loading while providing reduced pressure drops.