Bio-scrubber and Biofilter H2S/Odor Removal Testing @ Hyperion Treatment Plant

As part of the City's program to construct several new, large diameter interceptor sewers, 7 Air Treatment Facilities (ATFs) are being installed along with those facilities. The ATFs involve Bio-trickling filters as a primary air treatment stage followed by carbon adsorption as the polishing stage. This choice was based on extensive pilot testing which was reported in a previous paper presented at 2004 WEF/A&WMA Conference in Bellevue, Washington (Los Angeles Selects Bio-Trickling/Activated Carbon for Collection System Odor Control).In addition to these major ATF systems, the City has been addressing several smaller collection system “odor hot spots” through the use of carbon adsorption facilities. Although this technology is an effective odor control strategy, there are several drawbacks such as the high rate of carbon exhaustion and the cost of frequent carbon replacement. Building on the previous studies involving Bio-trickling filters followed by carbon adsorption, the City initiated the testing of Biofilters followed by carbon adsorption to determine if this might be an appropriate solution for the aforementioned “odor hot spots”. For comparison this treatment train was tested in parallel with the previously investigated system employing biotrickling filters followed by carbon adsorption.The new testing program took place at Hyperion Treatment Plant and the pilot facility was installed in such a fashion to draw upon the same odor source utilized in the original investigations so performance comparisons would be facilitated. The testing plan was designed to test both high and low H2S loading conditions that are expected throughout the City's collection system.