Successfully Coping With Off-Spec Odors in a Major, Publicly-Owned Wastewater Treatment Plant – A Case Study

Abstract

Many wastewater utilities undertake substantial capital investment for the design and construction of wastewater treatment odor reduction and control facilities. The utility owner is often confronted with the situation that "the plant is not operating at the same conditions as those for which the odor control facilities were designed." Or "the odors are not the same intensity and quantity as when the odor facility was designed" --and the system fails to meet performance expectations. This paper presents one such case history where the odors presented to the treatment system were "off-specification," and details the investigations and modifications required to make two separate and distinct odor control systems (a manufacturer-packaged biofilter, and a packed-bed, dual-chemical wet scrubber) meet their expected performance levels.During the initial startup and testing of each of these systems the foul air H 2 S concentrations were discovered to be an order of magnitude greater than those for which the facilities had been designed. This presentation discusses equipment and operational modifications made by the owner subsequent to the startup and testing of the designed systems, and outlines how those changes led to a subsequently successful operational history.