H sub(2)S, voc, TOC, electronic noses and odour concentration: use and comparison of different parameters for emission measurement on air treatment systems

Odour measurement via olfactometry is expensive and has a low accuracy compared with chemical or physical methods. In addition, olfactometry is not suited for online monitoring. Hence, an accurate online method for emission measurement would be an enormous improvement. There are several options to more or less replace the offline olfactometry by online measurement available today. Most common are H sub(2)S-concentration as a single gas parameter and VOC and TOC as composite parameters. A fairly new development are multi sensor arrays, usually referred to as "electronic noses" which carry out non-specific gas measurement and deliver measurement data that can visualized as a fingerprint diagram. This paper outlines the use of these different parameters and compares the results to those gained via olfactometry of several case studies.