Odour nuisance generated by food industry objects is a significant problem, the result of which is often numerous complaints from local residents about the quality of air. Apart from the production process, this problem often concerns industrial wastewater treatment processes, which contribute to a large extent to the emissions of odorants from the sulphur group, including hydrogen sulphide and mercaptans. In order to estimate the odorous air quality around these types of objects, the modelling of dispersion of pollutants: odours or odorants is often used. The paper presents the results of tests on odour emission as well as hydrogen sulphide and mercaptans emission as compounds typical for waste gases from the sewage treatment process from the food industry. In order to estimate the range of odour impact, model calculations using the Polish reference model for the aforementioned substances were made. The values of annual average concentrations and frequency of odour detection thresholds for odorants and odour concentration of 1 ouE/m 3 for odours as a mixture in a computational grid of 1400 m x 1400 m with a step of 50 m were calculated. The results showed the highest range of odour impact of mercaptans, whose value of the average annual concentration exceeded the odour detection threshold up to 700 m in the east and west direction from the emission source.

Abstract. Operation of municipal management facilities is inseparable from the problem of malodorous compounds emissions to the atmospheric air. In that case odor nuisance is related to the chemical composition of waste, sewage and sludge as well as to the activity of microorganisms whose products of life processes can be those odorous compounds. Significant reduction of odorant emission from many sources can be achieved by optimizing parameters and conditions of processes. However, it is not always possible to limit the formation of odorants. In such cases it is best to use appropriate deodorizing methods. The choice of the appropriate method is based on in terms of physical parameters, emission intensity of polluted gases and their composition, if it is possible to determine. Among the solutions used in municipal economy, there can be distinguished physico-chemical methods such as sorption and oxidation. In cases where the source of the emission is not encapsulated, odor masking techniques are used, which consists of spraying preparations that neutralize unpleasant odors. The paper presents the characteristics of selected methods of eliminating odor nuisance and evaluation of their applicability in municipal management facilities.

Odour concentration measurements in a chosen industrial source were made in this study using the method of dynamic olfactometry. The two different scenarios considered the variation of the odour emission rate as input for the dispersion model were compared for the period 2017 (before installation of the equipment for gas treatment) and 2018 (after implementation of purifying technologies). In this paper the odour impact range was determined by applying model calculations conducted in the Polish reference dispersion model -OPERAT FB software for the grid size 2 x 2 km. The conducted research shows a significant improvement in the odour impact range of chosen industrial source in year 2018 compared to 2017.