EXPLORING THE EFFECT OF ORGANIC ADDITIVES ON PHYSICAL PROPERTIES OF BITUMEN

Warm additives had wide popularity in recent years due to saving in energy and lowering emissions dealt with asphalt mixture production. Warm Mix Asphalt (WMA) is produced by using foaming technology or reducing -viscosity additives of binder to enhance the rheological properties. In this study, organic-based additives (Asphaltan A and Asphaltan B) are used to investigate their effect to minimize the viscosity and lower the temperature of asphalt mixture production. Bitumen is mixed with three doses of each additive: 1, 2, and 3% of its weight. The binder viscosity was measured by rotational viscometer with and without the additives at three different temperatures. The study showed that the organic additives have a positive impact on the behavior of the binder in terms of viscosity reduction and made enhancements in terms of bitumen properties. This result could be useful in the reduction of production temperature and quantity of odour emissions.

Environmental Odour Quantification by IOMS: Parametric vs. Non-Parametric Prediction Techniques

Odour emissions are a global issue that needs to be controlled to prevent negative impacts. Instrumental odour monitoring systems (IOMS) are an intelligent technology that can be applied to continuously assess annoyance and thus avoid complaints. However, gaps to be improved in terms of accuracy in deciphering information, especially in the implementation of the mathematical model, are still being researched, especially in environmental odour monitoring applications. This research presents and discusses the implementation of traditional and innovative parametric and non-parametric prediction techniques for the elaboration of an effective odour quantification monitoring model (OQMM), with the aim of optimizing the accuracy of the measurements. Artificial neural network (ANN), multivariate adaptive regression splines (MARSpline), partial least square (PLS), multiple linear regression (MLR) and response surface regression (RSR) are implemented and compared for prediction of odour concentrations using an advanced IOMS. Experimental analyses are carried out by using real environmental odour samples collected from a municipal solid waste treatment plant. Results highlight the strengths and weaknesses of the analysed models and their accuracy in terms of environmental odour concentration prediction. The ANN application allows us to obtain the most accurate results among the investigated techniques. This paper provides useful information to select the appropriate computational tool to process the signals from sensors, in order to improve the reliability and stability of the measurements and create a robust prediction model.

Impact of odour with high annoyance potential on human feeling, activity, and mood in odorimetric studies

Introduction. It is known that an extraneous odour can cause an adverse emotional reaction of a person and, as a result, reduce the quality of life, which is most likely the reason for a large number of complaints of air pollution from the population. The converse statement about the influence of a person’s emotional state on his/her perception of a smell can also be true. An assessment of the relationship between odour characteristics and emotional state of a person can be investigated in a laboratory olfactory-odorimetric study with the participation of specially trained investigators. The aim of this study was to analyze in laboratory conditions the impact of odour with high annoyance potential on human feeling, activity, and mood. Materials and methods. Ten 26-71-years healthy investigators of both genders, who have been psychologically tested with a block of standard psychological questionnaires to evaluate emotional stress expression and quality of life, took part in 2 series of odorimetric studies on the ECOMA T08 olfactometer. During this study, they assessed the odour intensity and annoying effect of multicomponent odorant with isopropyl mercaptan, ethyl mercaptan, and 2-butanethiol largest contribution (unpleasant odour). The influence of the odour on investigators’ feeling, activity, and mood before, during, and after odorimetry was determined using a FAM (feeling, activity, and mood) test card. The study results showed the perception of unpleasant smell to be connected with investigators’ age, emotional state at the time of odorimetry, and some indices of the life quality. It is established that the perception of the smell in its tangible concentrations can lead to increased activity and improved mood. At the same time, exposure to the odour in higher concentrations, in most cases, was associated with decreased activity and mood, as well as - for some investigators - with decrease of feelings regardless of age. The given work results comparison with data obtained in the only similar study of odour emissions of chewing gum production carried out with a common methodic approach and on the same equipment, demonstrated a qualitative similarity in the perception of an extraneous odour of different hedonic tone: a connection with age, background emotional state, and quality of life indicators. Moreover, it was revealed odours of different hedonic tones to influenced in the same way on investigators’ activity and mood indices. Conclusion. Although the obtained results do not allow us to unambiguously conclude which odour strength (concentration of odorous substances) is an unacceptable value for all investigators, the similar research implementation is necessary to study the odour impact on the human adaptation systems. In addition, the data obtained allow us to conclude that all complaints of the presence of an extraneous odour of any character and hedonic tone, are most often justified, deserve careful attention and a quick response from the sanitary services.

Optimization of Classification Prediction Performances of an Instrumental Odour Monitoring System by Using Temperature Correction Approach

Odour emissions generated by industrial and environmental protection plants are often a cause of nuisances and consequent conflicts in exposed populations. Their control is a key action to avoid complaints. Among the odour measurement techniques, the sensory-instrumental method with the application of Instrumental Odour Monitoring Systems (IOMSs) currently represents an effective solution to allow a continuous classification and quantification of odours in real time, combining the advantages of conventional analytical and sensorial techniques. However, some aspects still need to be improved. The study presents and discusses the investigation and optimization of the operational phases of an advanced IOMS, applied for monitoring of environmental odours, with the aim of increasing their performances and reliability of the measures. Accuracy rates of over 98% were reached in terms of classification performances. The implementation of automatic correction systems for the resistance values of the measurement sensors, by considering the influence of the temperature, has been proven to be a solution to further improve the reliability of IOMS. The proposed approach was based on the application of corrective coefficients experimentally determined by analyzing the correlation between resistance values and operating conditions. The paper provides useful information for the implementation of real-time management activities by using a tailor-made software, able to increase and enlarge the IOMS fields of application.

Environmental Odour Nuisance Assessment in Urbanized Area: Analysis and Comparison of Different and Integrated Approaches

Prolonged exposure to odour emissions causes annoyance which leads to nuisance and consequently to complaints. Different methodologies exist in the literature to evaluate odour impacts, but not all are suitable to assess environmental odour nuisance. Information about their applicability criteria and comparison, is scarce and referred to short time analysis. The research presents and discusses the application of different methods to characterize and assess odour nuisance around an industrial plant localized in a sensitive area. Experimental activities are carried out through a long-time analysis programme. Field inspections and predictive methods are investigated and compared. A modification of the traditional dispersion modelling approach is proposed in order to adapt its application for the prediction of the odour nuisance. The offensiveness and location factors are identified as key parameters in the quantification of the perceived nuisance. The integrated dispersion modelling multi-level approach is highlighted as the most suitable for defining the plant strategies. The paper provides useful information to characterize environmental odour problems and identify appropriate solutions for an effective management of odorous sources, with the aim of reducing complaints, restoring the proper relationship between odorous plants and the surrounding communities and increasing the overall quality of the environment.

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

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.

Summary and Overview of the Odour Regulations Worldwide

When it comes to air pollution complaints, odours are often the most significant contributor. Sources of odour emissions range from natural to anthropogenic. Mitigation of odour can be challenging, multifaceted, site-specific, and is often confounded by its complexity—defined by existing (or non-existing) environmental laws, public ordinances, and socio-economic considerations. The objective of this paper is to review and summarise odour legislation in selected European countries (France, Germany, Austria, Hungary, the UK, Spain, the Netherlands, Italy, Belgium), North America (the USA and Canada), and South America (Chile and Colombia), as well as Oceania (Australia and New Zealand) and Asia (Japan, China). Many countries have incorporated odour controls into their legislation. However, odour-related assessment criteria tend to be highly variable between countries, individual states, provinces, and even counties and towns. Legislation ranges from (1) no specific mention in environmental legislation that regulates pollutants which are known to have an odour impact to (2) extensive details about odour source testing, odour dispersion modelling, ambient odour monitoring, (3) setback distances, (4) process operations, and (5) odour control technologies and procedures. Agricultural operations are one specific source of odour emissions in rural and suburban areas and a model example of such complexities. Management of agricultural odour emissions is important because of the dense consolidation of animal feeding operations and the advance of housing development into rural areas. Overall, there is a need for continued survey, review, development, and adjustment of odour legislation that considers sustainable development, environmental stewardship, and socio-economic realities, all of which are amenable to a just, site-specific, and sector-specific application.