DESIGN AND OPERATING EXPERIENCES FROM THE BIOFILTER

As a result of the increasing encroachment of neighbors on wastewater processing facilities, the need to treat odorous emissions has increased. This has resulted in continuous improvement in the design and operation of odor treatment technologies. Biofiltration is one technology that is utilized to treat odorous emissions and help solve odor problems. Its use is attractive to many facilities because of its high odor reduction capabilities, simple operation, and low cost. Several different types of biofiltration systems are currently being utilized. Recent design improvements and successful operating experiences have resulted in the continued increase in the use of biofilters.This paper will present information on five biofilter applications. These applications span several areas of the wastewater treatment process.Town of Cary, North Carolina: 2,300 cubic feet per minute (CFM) from a one million gallon per day (MGD) pump station. Currently under construction with completion scheduled for February 2000.Western Lake Superior Sanitary District, Scanlon, Minnesota: Two stage 3,000 CFM biofilter at a 48 MGD pump station treating mostly papermill odorous emissions. Constructed in 1997.City of Roseville, California: 20,000 CFM of odorous air from headworks. Constructed in 1998.Western Lake Superior Sanitary District, Duluth, Minnesota: 50,000 CFM from headworks, grit removal, and sludge thickening. Constructed in 1996.Hoosac Water Quality District, Williamstown, Massachusetts: 21,000 CFM from a ten dry ton per day (DTPD) modified aerated static pile biosolids composting facility constructed in 1992 and expanded in 1997.Design parameters, design features, media life, costs, operating experiences, and odor removal performance will be presented.