Application of Field Olfactometry to Monitor the Odour Impact of a Municipal Sewage System

Abstract

Odorant emissions are associated with, among other things, wastewater transport in sewer networks; they contribute to air pollution and result in complaints from residents living close to emission sources. The critical location in terms of the formation of unpleasant odour compounds is the pressure line that connects the pumping station and the expansion well; this is where they are released into the atmosphere. This paper presents comprehensive results of olfactometric and chromatographic tests in the Polish city of Białystok using portable devices that allow for multiple determinations and instant results. The study attempts to investigate the relationship between odour and odorant concentrations and check the suitability of field olfactometry as a tool for the ongoing monitoring of the emission of noxious odours and for verifying complaints submitted by residents. Statistical analysis shows a very high correlation coefficient between cod and the concentrations of individual odorants, ranging from 0.82 to 0.91. This olfactometric research, mainly conducted in situ, can be an appropriate method for the ad hoc monitoring of processes in sewage networks. This method allows the detection of unwanted emissions of odours at individual points in the network in concentrations that are not detected by standard sensors but that nevertheless cause odour nuisances, complaints, and social conflict. The research results provide evidence in favour of the energetic usage of wastewater, which is in line with circular economy conception, since odour nuisance is one of its indicators.

Deodorisation of Ventilated Air from a Fat-Processing Plant Using Different Types of Biofilter Fillings and Membranes

“…Portable field olfactometers were used for olfactometric measurements, which allowed for a calibrated series of dilutions to be performed by mixing contaminated, odorous air with pure, filtered air. Odour concentration value is determined in units of odour (ou, according to the European standard PN-EN 13725:2022 [38]) per unit of volume [ou/m 3 ] [39,40]. Scentroid SM100 is a field olfactometer ranging between 2 and 30,000 ou/m 3 [41].…”

Wastewater Treatment Plants as a Source of Malodorous Substances Hazardous to Health, Including a Case Study from Poland

“…The problem of unpleasant odours associated with wastewater treatment begins at the stage of bringing wastewater to the treatment plant through the sewer system and its components (zone I) [ 2 , 12 , 13 , 14 , 15 ].…”

“…Zone one equipment, i.e., pumping stations, waste disposal points, sump pits and sewer lines, are points where wastewater can rot, resulting in the formation of odorants (mainly hydrogen sulphide is formed) [ 12 , 13 , 14 ]. During the processes carried out in the equipment of zone two (they are supposed to ensure the removal of solids, mineral fines and fractions of oils and fats), many odour compounds are generated, especially hydrogen sulphide.…”

“…Another technique included within the sensory methods is field olfactometry, for which special equipment is used. It involves analysing the air directly at the source and, unlike direct olfactometry, avoids errors due to changes in the composition of the sample during transport and collection in a bag designed for this purpose [ 14 , 48 ]. The use of in situ olfactometers makes it possible to directly estimate the concentration of odour at a given measurement point.…”

Variability of Odour Emissions from Selected Passive Area Source: Preliminary Analysis for a One-year Study at a Municipal Wastewater Treatment Plant in Poland

“…Similarly, field olfactometry (Cesca et al 2007, Pan et al 2007, Wiśniewska et al 2020, Damuchali & Guo 2019 and, more commonly, the electronic nose as an artificial olfactory sense (Giungato et al 2016, Wilson & Baietto 2009, Jońca et al 2022) are used in the odour impact analyses. Field measurements are also used to estimate the odour impact area of existing facilities (Barczak & Kulig 2017, Kulig et al 2022. Odour intensity results from field measurements, processed with statistical and geostatistical tools, can be used to determine the odour impact of an installation (Szymański et al 2015, Hawko et al 2021).…”