Abstract
Englewood, Florida is a tourist community of about 15,000 people located on the Gulf of Mexico, south of Sarasota and north of Fort Myers. The Englewood Water District (EWD) operates the Water Reclamation Facility (WRF) located in Placida, FL. The plant receives about 1.8 Million Gallons Per Day (MGD) of wastewater flow during the winter and about 1.1 MGD during the summer months. Hydrogen Sulfide (H2S) concentrations were very high in raw sewage tanks, ranging from 300 to 800 ppm.
The District had received odor complaints from the surrounding community and unfortunately one of their odor control units was mostly ineffective in controlling odors from the facility as some raw sewage tanks were not covered.
Odor control solutions were developed that utilized some of the unique aspects of this treatment plant which significantly reduced the overall costs. These innovative solutions included:
- By-passing four (4) raw sewage receiving tanks that were not needed to minimize the number of tanks to be covered and the amount of air to be collected and treated.
- Taking some return activated sludge (RAS) to the screened plant influent to tie up sulfides in the raw sewage and reduce H2S emissions in the flow equalization (surge) tanks at each of the four individual package plants
- Replacing an existing single stage horizontal bioscrubber that had failed with a 1st stage vertical bioscrubber followed by a 2nd stage biofilter to polish H2S and odors.
- Converting one of the existing concrete tanks that were taken out of service into a 2nd stage of treatment biofilter.
The primary objectives of this project were to control odor emissions to the point where odors could no longer be detected by neighbors surrounding the site and to meet the requirements of a Consent Order agreed to with the Florida Department of Environmental Protection. This was achieved by identifying, quantifying and ranking all odor sources at the facility, developing an Odor Control Master Plan and designing/constructing the most reliable, efficient and cost effective odor control facilities possible. This was accomplished by optimizing the use of existing facilities and providing creative odor control solutions.
The project began in January 2012 and construction was completed in September, 2013. Performance testing was conducted in October, 2013, and the results are presented in this paper.
Keywords
Innovative Odor Control, Bioscrubber, Biofilter, Return Activated Sludge for Odor Control, Consent Order, Englewood, Florida
