Odour Impact Assessment by a Multiparametric System (electronic Noses/ch4-nmhc Analyser)

Odour impacts are assessed according to two principal approaches: evaluation and estimation of the pollutant relapse on the territory and monitoring through standard methodologies. In particular, odour monitoring is characterized by a great complexity due principally to the strict association of odour pollution to human perception. The standardized methodology for the determination of odour concentration is represented by an instrumental sensory technique, the dynamic olfactometry, that is affected by some limitations. This methodology provides punctual odour concentration data and it does not allow to perform continuous and field measurements, useful for monitoring the industrial processes causing odour emissions. The need of carrying out a continuous monitoring having been encouraged the use of an odour surrogate monitoring, performed by specific or not specific instruments (chemical analysers or electronic noses). The surrogate measurements employment is based on the fact that the ratio of surrogate concentration to odour units must be relatively constant and known. This paper focuses on the development of a multiparametric system for the evaluation of odour impact caused by an industrial source. The system has been tested during olfactometric monitoring campaigns conducted at the industrial site, coupling the results of electronic noses. The purpose of the research work has been to find an indicator for the odour emissions produced by the examined industrial site, and to correlate it with odour concentrations. This study has allowed to demonstrate the real applicability of not specific instruments to odour continuous monitoring, useful to detect a change of state in operating conditions of industrial processes and control it.