The Use of Chemical Sensors to Monitor Odour Emissions at Municipal Waste Biogas Plants

Abstract

Municipal waste treatment plants are an important element of the urban area infrastructure, but also, they are a potential source of odour nuisance. Odour impact from municipal waste processing plants raises social concerns regarding the well-being of employees operating the plants and residents of nearby areas. Chemical methods involve the determination of the quantitative composition of compounds comprising odour. These methods are less costly than olfactometry, and their efficiency is not dependent on human response. The relationship between the concentration of a single odorant and its odour threshold (OT) is determined by the odour activity value (OAV) parameter. The research involved the application of a multi-gas detector, MultiRae Pro. Measurements by means of the device were conducted at three municipal waste biogas plants located in Poland. In this paper we describe the results obtained when using a detector during the technological processes, the unitary procedures conducted at the plants, and the technological regime. The determination of these relationships could be useful in the development of odour nuisance minimization procedures at treatment plants and the adjustment to them. This is of paramount importance from the viewpoint of the safety and hygiene of the employees operating the installations and the comfort of residents in the areas surrounding biogas plants. Monitoring of expressed odorant emissions allows the course of technological processes and conducted unit operations to be controlled.

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

“…The decomposition of the organic fraction by microorganisms is cited as the main cause of odour emissions from landfills [59]. For this type of waste, parameters such as C/N ratio, temperature, moisture content and pH can influence the ammonia concentration [20,60,61]. When analyzing the concentrations of volatile sulphur compounds, their level may be determined mainly by the temperature and oxygen concentration [60,62].…”

“…The situation is much more difficult to interpret in the case of VOCs, which cover a wide range of compounds having carbon in their structure. In the case of studies carried out in biogas plants processing municipal waste, during which besides olfactometry and detector also gas chromatography was used [20], the dominating VOCs were the compounds styrene (OT = 0.047 ppm [75]), phenol (OT = 0.048 ppm [76]) and toluene (OT = 0.33 ppm [77]), which, apart from unpleasant odour, are also characterized by a dangerous effect on human health and life. Analyzing the results presented and the characteristics of the compounds, it can be concluded that the recultivation activities carried out on the site do not comply with the decision issued by the state authority or with the definition of recultivation.…”

“…The compounds characteristic for organic matter decomposition processes occurring at municipal waste management plants (mechanical-biological waste treatment plants (MBTP), municipal waste biogas plants (MWBP) and landfills) include mainly alkanes, alkenes, ketones, terpenes and a broad spectrum of volatile organic compounds (VOCs) [19][20][21][22][23]. Some of these substances are formed by decomposition processes of sulphur-and nitrogen-containing compounds.…”

“…The application of chemical sensors and sensory methods enable monitoring technological processes in waste management plants, demonstrated in [20,50]. This research aims to verify whether chemical air quality tests can, together with olfactometric analyses, have practical application in ecological audits of the areas.…”

Electronic Noses and Their Applications for Sensory and Analytical Measurements in the Waste Management Plants—A Review

“…Wiśniewska et al [75] used a portable multi-gas analyzer, MultiRae Pro, equipped with one PID detector and three electrochemical sensors to measure H 2 S, NH 3 and methanethiol for the monitoring of odorants emitted from biogas plants. The highest concentrations of odorants were associated with oxygen stabilization of digestate (VOCs, NH 3 ) and with technological wastewater generated at biogas plants (mainly NH 3 ).…”