Odor Abatement System Helps Keep N.C. Mountain Air and Water Clean

As part of a long-term plant expansion, Charlotte-Mecklenburg Utilities is installing six carbon adsorbers from USFilter RJ Environmental Products at the McDowell Creek Wastewater Treatment Plant (WWTP) in Huntersville, N.C.

Comprised of Midas OCM (odor control media) from USFilter Westates Carbon, each odor abatement system will help eliminate hydrogen sulfide and other organic odors in headworks, influent pump stations and day tanks.

Four systems at the headworks and influent pump station areas will each handle an air flow rate of 10,125 cubic feet per minute (cfm). The day tanks area will have two 11,775-cfm systems. In total, USFilter's odor abatement systems will treat a combined air flow rate of 64,050 cfm. The McDowell Creek installation is scheduled to come online in Fall 2006.

The 23-year-old McDowell Creek plant currently treats 6 million gallons per day (mgd). Population growth and the resulting increased wastewater flows hastened the facility's decision to double its capacity over the next two years. A community Stakeholders Group helped the utility decide what would be the best wastewater management approach for the service area. The final design includes state-of-the-art treatment technologies to meet very stringent permit requirements. Providing odor control facilities as part of the plant expansion will help meet the expectations of the local community and Stakeholders Group.

Although seemingly complex, the odor abatement systems work very simply. Foul air flows through densely packed beds of Midas OCM to adsorb H2S. The media's H2S adsorption capacity is three to six times that of other carbons. As the OCM is not impregnated, it is much safer to use and has a longer bed life than impregnated media. For Charlotte-Mecklenburg Utilities, this means fewer service interruptions and lower operations and maintenance costs.

In the past five years, the Association of Metropolitan Sewerage Agencies has annually recognized the McDowell Creek WWTP with either a Gold or Silver award for consistently complying with treatment requirements.

Birmingham, Ala.-based Brasfield & Gorrie, LLC is the general contractor for the project, and Kansas City, Mo.-based Black & Veatch, the engineer. Heyward, Inc. is USFilter's Charlotte, N.C.-based representative.

Source: USF