Battle Creek, MI
Duncan Aviation in Battle Creek, Michigan operates an aircraft maintenance and repair facility, including airframe and engine maintenance, paint and interior refurbishment, avionics installations and avionics line work. As part of the painting process, a methylene chloride/phenol based stripper is used to remove paint. Wastewater is currently collected from three paint hangars and treated for heavy metals removal. Treatment includes chromium reduction, metals precipitation,  clarification, and pH adjustment as the primary process. This treatment process was not capable of removing methylene chloride or phenol which are classified as total toxic organics (TTOs).

After a feasibility study and pilot testing, Fenton’s reagent was selected as the preferred treatment method to reduce TTOs to within effluent limits. Fenton’s reagent is a solution of hydrogen peroxide and an iron catalyst that is used to oxidize contaminants such as TTOs. WLA completed final design and process modifications to incorporate this treatment process. The design utilized a reactor in series with the existing metals treatment system. Multiple equalization tanks were also added to increase storage capacity and to allow the segregation of TTO containing wastewater. This allows non-TTO containing wastewater to bypass the reactor, saving chemical costs.