HIGH CAPACITY ACTIVATED CARBON: FULL-SCALE INSTALLATIONS DEMONSTRATE EXCEPTIONAL ODOR CONTROL

In the past, application of activated carbon for odor control at wastewater treatment facilities was limited to locations with very low odors. Activated carbon was not considered applicable for moderate hydrogen sulfide and VOC loads due to frequent replacement requirements and the resulting operation and maintenance costs. With the advent of improved types of activated carbon media, however, this technology now has innovative applications. This paper discusses the advances in activated carbon odor control technology and presents full-scale, operational case-studies which document the performance of each type of system. Operational and maintenance issues for each system are addressed in addition to performance monitoring.Several vendors have developed new high capacity carbon media, expanding the range in which application of an activated carbon system is cost effective. USFilter has developed Midas™ media. Midas™ media has a high hydrogen sulfide (H2S) capacity and is designed to be used once andreplaced. The City of Los Angeles. Hyperion wastewater treatment plant installed a polishing Midas™ carbon system in 2002, and the City of Olathe, Kansas retrofitted their sludge processing odor control carbon unit and installed Midas™ media in early 2003. Extensive monitoring and testing for both hydrogen sulfide and outlet odor indicate the systems are providing excellent overall odor control, with outlet odor levels consistently less than 150 DT.PureAir Filtration supplies Sulphasorb XL™ media. Sulphasorb XL™ was recently introduced to the market and is a high grade activated carbon impregnated with an acid gas neutralizing compound and two proprietary reagents which improve its neutralizing and adsorption efficiency. PureAir has also introduced new configurations for the carbon system, including vertical tube system (VTS) and vertical bed system (VBS). These draw-thru configurations allow installation of several types of activated carbon media, to provide the most cost effective odor control system.These systems have successfully expanded the niche where activated carbon can provide cost effective odor control. These case studies have shown that for low to moderate odor levels, activated carbon can provide effective, efficient odor control in a small footprint with minimal operation and maintenance requirements. This paper is important to both practitioners and facility owners because advancements in activated carbon system design and media development provide a solution to the increasingly stringent fence-line odor requirements enforced at many wastewater treatment facilities.