Odour measurement in wastewater treatment plant by a new prototype of e.nose: Correlation and comparison study with reference to both European and Japanese approaches

In the modern world of wastewater treatment, control of odors has moved from an afterthought to a primary design consideration for most collection and treatment facilities. As development encroaches on our facilities and our new neighbours become less tolerant of nuisance odors, wastewater professionals have found the need to address odor as a primary concern in the design and operation of collection and treatment facilities. When facility odors affect air quality and cause citizen complaints, an investigation of those odors may require that specific odorants be measured and that odorous air be measured using standardized scientific methods. Odour intensity is one of main odour characterization parameters, and remarkably common and important sensory indicator of environmental odours. Odour intensity reflects people's perception of odours and contributes to effective odour management. The triangle odors bag method', which has been adopted for the offensive odors control law in Japan, and the dynamic olfactometry defined by EN 13725 has been adopted in Europe. These methods are the worldwide used for as reference methods for the sensorial measurement of odours. On these methods are also based the training of electronic nose (e.Nose). In this study odour samples were collected on municipal wastewater treatment plant located in south Italy at four different treatment units to determine the relationship between odour intensity assessed by Japanese triangle odors bag method', odour concentration measured with dynamic olfactometry according to European standard EN13725:2003 and with odour concentration measured by a novel prototype of e.Nose patented by University of Salerno. A monthly sampling and relative measurements were carried out for consecutive 12 months at Laboratory of Sanitary Environmental Engineering Division (SEED) at University of Salerno (Italy). Results show when high odours were detected by Japanese standard, the odour concentrations measured according European standard were also high (e.g. emission from sludge line). Concentrations measured by e.Nose are strongly correlated with the measurements carried out by standard methods.