ODOR EMISSION CAPACITY OF LIQUIDS – METHODOLOGY AND APPLICATION AT WASTEWATER SYSTEMS

Odors from the wastewater industry can cause major annoyance in the neighborhood. Unlike all other parameters dealing with the characterization of liquids from the wastewater industry, there is no well defined parameter “odor” for liquids, and the field tests available are not very expressive and not useful. Liquids from the wastewater industry comprise domestic or municipal wastewater, industrial wastewater discharged into publicly owned sewer systems, wastewater conveyed in the sewer system, especially pressure mains, and all process waters in a wastewater treatment plant.On the other hand, a quantification of the content of odorants in the liquid phase is urgently needed for many reasons. Examples are the quantification of relevance of different liquids concerning odor, the identification of odor-relevant liquid streams, the implementation of standards for maximum odorants content of liquids, e.g. from industrial enterprises, as well as the surveillance of the compliance with set standards setting standards. These days in Germany, the most important application is the objective determination of the effinciency of measures against sewerage odors. Several chemicals can be added to a sewer in order to minimize or even solve odor problems from sewer systems. However, the determination of the odor emission capacity OEC, as introduced by Frechen and Köster (1998), is necessary in order to be able to objectively quantify the efficiency of different chemicals and different dosing strategies.The methodology of the odor emission capacity OEC is explained and the application in the wastewater industry is highlighted in this paper. Results of case studies, especially concerning industrial wastewater and the use of chemical dosing for suppression of odor emissions from sewers, are presented.The odor emission capacity (OEC) measurement method is a very essential and valuable tool for solution of several problems connected to odors in the wastewater industry.