The Air and Sewage Pollutants from Biological Waste Treatment

Abstract

The mechanical-biological waste treatment plants (MBTP), which include the municipal waste biogas plants, have an important role in sustainable urban development. Some plants are equipped with a sewage pre-treatment plant, which is then directed to the sewerage system and the treatment plant. Others, on the other hand, have only a non-drainage tank. The parameters of technological sewage (TS) or processing technology could reduce sewage contamination rates. In addition to the quality of sewage from waste treatment plants, the emission of odours is also an important problem, as evidenced by the results obtained over the sewage pumping station tank. The conducted statistical analysis shows a significant positive correlation between odour concentration (cod) and volatile organic compounds (VOCs). Analysing the individual compounds, a high positive correlation was also found—the strongest being between H2S, NH3 and VOCs. In the case of sewage compounds, the insignificant correlation between P total and other parameters was found. For the rest of the compounds, the highest positive correlation was found between COD and BOD and N-NO2 and N-NH3 as well as COD and N-NO2. The dilution of sewage is only an ad hoc solution to the problem. Further work should be aimed at reducing sewage pollution rates. The obtained results indicate large pollution of technological sewage and a high level of odour and odorants concentration. The novelty and scientific contribution presented in the paper are related to analyses of various factors on technological sewage parameters and odour and odorant emission from TS tank at biogas plant processing municipal waste, which may be an important source of knowledge on the management of TS, its disposal and minimisation of emitted compound emissions.

Application of Chemical Sensors and Olfactometry Method in Ecological Audits of Degraded Areas

“…The D/T value is the number of dilutions required to achieve a dilution in the ambient air that the odour is undetectable. Owing to the application of these olfactometers, it is possible to calculate the D/T value and, on its basis, the odour concentration value, determined as c od in odour units (ou—odour unit, analogically to the European standard [ 46 ]) per volume unit [ou/m 3 ] [ 36 ]. Temperature (T, °C) and relative humidity (RH, %) were measured using a Rotronic HydroPalm psychrometer with HygroClip2 HC2-S3 sensor.…”

“…These methods can be generally divided into laboratory methods, which require sampling a gas using a unique bag and its determination under laboratory conditions, and field methods. Both the sampling and its resolution are performed at the source (in the field) [ 36 , 37 ].…”

Archives of Environmental Protection

“…Mixed municipal waste is treated in MBT plants in two stages. The first stage is mechanical preparation of waste for biological processes, and the second stage is biological decomposition of waste (Colón et al 2017, Wiśniewska and Szyłak-Szydłowski 2021). The biological process can be carried out in an aerobic manner (in the form of composting) or using anaerobic conditions (fermentation) and then subjecting the fermentation residues to aerobic stabilization (Fei et al 2018, Wiśniewska and Szyłak-Szydłowski 2021).…”

“…The first stage is mechanical preparation of waste for biological processes, and the second stage is biological decomposition of waste (Colón et al 2017, Wiśniewska and Szyłak-Szydłowski 2021). The biological process can be carried out in an aerobic manner (in the form of composting) or using anaerobic conditions (fermentation) and then subjecting the fermentation residues to aerobic stabilization (Fei et al 2018, Wiśniewska and Szyłak-Szydłowski 2021). The combination of mechanical and biological processes minimizes the amount of landfilled waste and recovers useful fractions from the waste stream that can be reused, e.g., ferrous and non-ferrous metals.…”

“…The authors indicated acetic acid, butyric acid, valeric acid, isovaleric acid, and dimethyl sulfide as the most odor-generating substances. Wiśniewska et al (2019Wiśniewska et al ( , 2020 researched the emission of odorants and odors from 6 MBT plants in Poland, which had the installation for anaerobic decomposition (fermentation) of the organic matter contained in mixed municipal waste (Wiśniewska 2020a, Wiśniewska 2020b, Wiśniewska and Szyłak-Szydłowski 2021, Wiśniewska et al 2019. The conducted research concerned mainly the analyzes of substances such as VOC (measured values of a dozen or so ppm on average), ammonia (a dozen or so ppm on average), hydrogen sulfide (not more than a few ppm), dimethyl sulfide, methyl mercaptan (usually below one ppm) and analyzed the concentration of odors using field olfactometry.…”