Odour Emissions and Odour Control at Wastewater Treatment Plants in West Germany

Odour emissions caused by wastewater treatment plants can bring serious annoyance to the plant9s staff and local residents. A measurement technique is required that corresponds to the human impression of smell. Thus, olfactometry was used to determine the odour strength. Many facts contribute to the formation and release of odorous emissions. Surveys as well as measurement programs indicate that the sludge part of a wastewater treatment plant is the most critical part. Different types of waste air treatment plants are in use in West Germany. Regarding the total amount of waste air to be deodorized, chemical scrubbers play the major role today. Looking at the numbers of plants, bio-filters are most common. Biological waste air treatment systems are of increasing importance in West Germany.