Performance Validation of a Shell-Media Biological Odor Control System

Orange County Utilities conducted pilot testing of a shell-media based biological odor control system at the Stillwater Crossing Pump Station. The shell media has the desirable qualities of availability, low cost, long life, and high sustainability. The purpose of the pilot testing was to verify that the system could provide acceptable H2S and odor removal. A skid-mounted, modular pilot unit consisted of a bolted FRP panelled housing, seashell media, control panel, two FRP irrigation sumps, two water recirculation pumps, and a fan with unit-to-fan ductwork and a vertical exhaust stack. The pilot unit was started at 2.83 m3/min (100 cfm) and after successful operation was confirmed the airflow was increased to 7.1 m3/min and finally to 14.2 m3/min (250 and 500 cfm). An ambitious sampling program was performed over a period of 8 months. The data showed that the pilot system provided over 99 percent H2S removal at inlet concentrations as high as 124.5 ppm. The pilot unit also provided very good odor removal efficiencies of 98.9, 97.6, 99.6, and 98.9 percent with corresponding final outlet odor of 920, 620, 350, and 575 DT.