Robert Oleniacz | AGH University of Science and Technology (original) (raw)

Papers by Robert Oleniacz

Sustainability, Oct 18, 2024

The episodes of elevated concentrations of different gaseous pollutants and particulate matter (P... more The episodes of elevated concentrations of different gaseous pollutants and particulate matter (PM) are of major concern worldwide, especially in city agglomerations. Krakow is an example of an urban–industrial agglomeration with constantly occurring PM10 air limit value exceedances. In recent years, a number of legislative actions have been undertaken to improve air quality in this area. The multitude of factors affecting the emergence of cases of very high air pollutant concentrations makes it difficult to analyze them using simple statistical methods. Machine learning (ML) methods can be an adequate option, especially when proper amounts of credible data are available. The main aim of this paper was to examine the influence of various factors (including main gaseous pollutant concentrations and some meteorological factors) on the effect of high PM10 concentration pisodes in the ambient air in Krakow (Poland) using the random forest algorithm. The original methodology based on the PM10 limit and binary classification of cases with and without the occurrence of high concentration episodes was developed. The data used were derived from routine public air quality monitoring and a local meteorological station. A range of random forest classification models with various predictor sets and for different subsets of the observations coupled with variable importance analysis were performed. The performance of the algorithm was assessed using confusion matrices. The variable importance rankings revealed, among other things, the dominant impact of the mixing layer height on elevated PM10 concentration episode formation. This research work showed the usefulness of the random forest algorithm in identifying factors contributing to poor air quality, even in the absence of reliable emission data.

The paper presents the new method for measurements of air particulate size distribution in real t... more The paper presents the new method for measurements of air particulate size distribution in real time using Kamika Infrared Particulate Sizer type P (IPS-P) with isokinetic air sampler. The device makes it possible to classify (sort) air particulates according to size into 256 granularity classes from about 0.4 µm up to 300 µm. Tests of the IPS-P prototype were conducted in Warsaw at the turn of 2005/2006 and some measurement results were presented in the work. English title: Measurements of the particulate size distribution in the air in real-time.

This article presents a complex analysis of the impact of the technology of continuous casting of... more This article presents a complex analysis of the impact of the technology of continuous casting of steel (CCS) on the rate of the air pollutant emissions from one of the Polish steel and iron plants. The emission sources occurring in the production process have been identified and their rate has been determined. The implementation of CCS has brought about significant changes in the production cycle of the steel plant and it also has caused an increase of the production effectiveness of steel products. The calculated environment effects have shown a considerable emission decrease of all pollutants in the scale of the whole steel plant. English title: Assessment of ecological effects of the implementation of continuous casting of steel.

Sustainability, Vol. 13, Issue 10, 5623, May 18, 2021

In cities with an extensive air quality monitoring (AQM) system, the results of pollutant concent... more In cities with an extensive air quality monitoring (AQM) system, the results of pollutant concentration measurements obtained in this system can be used not only for current assessments of air pollution, but also for analyzes aimed at better identification of factors influencing the air quality and for tracking trends in changes taking place in this regard. This can be achieved with the use of statistical methods that allow for the assessment of the variability of measurement data observed at stations of various types and for the determination of possible interdependencies between these data. In this article, an analysis of this type was carried out for traffic, urban background and industrial AQM stations in Krakow (Southern Poland) operating in the years 2017–2018 with the use of, i.a., cluster analyzes, as well as dependent samples t-test and Wilcoxon signed-rank test, taking into account the concentrations of air pollutants such as fine particulate matter (PM10), nitrogen dioxide (NO2), benzene (C6H6) and sulfur dioxide (SO2). On the basis of the conducted analyzes, similarities and differences were shown between the data observed at individual types of stations, and the possibilities of using them to identify the causes of the observed changes and the effects of remedial actions to improve air quality undertaken recently and planned in the future were indicated. It was found that the air concentrations of some substances measured at these stations can be used to assess the emission abatement effects in road transport (NO2, PM10 or C6H6), residential heating (PM10 or SO2), and selective industrial plants (SO2, NO2 or C6H6).

IOP Conf. Series: Earth and Environmental Science, Vol. 642, Issue 012013, Feb 15, 2021

Air pollution in urban-industrial areas is caused by simultaneous impact of many factors, includi... more Air pollution in urban-industrial areas is caused by simultaneous impact of many factors, including different types of emission sources. Ambient air quality in Krakow is a crucial problem regarding the regularly occurring exceedances of limit values of particulate matter and some of its chemical compounds. This paper presents quantification of urban, suburban and industrial background of dust substances concentrations that are present in the industrialized area, located in the vicinity of scattered household and road traffic emission sources. There were included the concentrations of such substances as: particulate matter (PM10), benzo(a)pyrene, arsenic, cadmium, lead and nickel. The impact of daytime and season of the year (especially heating and non-heating season) on variability of air pollutant concentrations was examined. In order to distinguish between local and inflow background of air pollutants the additional meteorological data concerning wind speed and direction was considered. The performed analyses included application of statistical methods, among others principal component analysis (PCA). Some of the results were visualized via R programming environment, providing tools for air pollution data processing (openair package). The backward trajectories modelling using HYSPLIT model, allowed the validation of wind direction analyses. The conducted research revealed the strong dependence of air pollution background type influencing the measurement results on instantaneous wind direction.

Atmosphere, Vol. 11, Issue 7, 695, Jun 30, 2020

One of the elements of strategy aimed at minimizing the impact of road transport on air quality i... more One of the elements of strategy aimed at minimizing the impact of road transport on air quality is the introduction of its reorganization resulting in decreased pollutant emissions to the air. The aim of the study was to determine the optimal strategy of corrective actions in terms of the air pollutant emissions from road transport. The study presents the assessment results of the emission reduction degree of selected pollutants (PM 10 , PM 2.5 , and NO x) as well as the impact evaluation of this reduction on their concentrations in the air for adopted scenarios of the road management changes for one of the street canyons in Krakow (Southern Poland). Three scenarios under consideration of the city authorities were assessed: narrowing the cross-section of the street by eliminating one lane in both directions, limiting the maximum speed from 70 km/h to 50 km/h, and allowing only passenger and light commercial vehicles on the streets that meet the Euro 4 standard or higher. The best effects were obtained for the variant assuming banning of vehicles failing to meet the specified Euro standard. It would result in a decrease of the yearly averaged PM 10 and PM 2.5 concentrations by about 8-9% and for NO x by almost 30%.

E3S Web of Conferences, Vol. 45, Issue 00060, Jul 30, 2018

The paper presents a comparison of air pollutant concentrations in three cities in SouthEastern P... more The paper presents a comparison of air pollutant concentrations in three cities in SouthEastern Poland (Krakow, Tarnow and Rzeszow) using statistical analyses and backward trajectory modelling (the HYSPLIT model). The analyses were based on particulate matter (PM10), nitrogen dioxide (NO2) and sulphur dioxide (SO2) levels as well as meteorological data from year 2017. The performed analyses revealed, among others, that the PM10 and SO2 concentrations in the air depend on the season of the year, while the NO2 concentrations are seasonally independent, which is mainly associated with emissions from road transport. Air quality in the analysed cities depends on local meteorological conditions and the structure of emission sources, including the inflowing background. The most unfavourable situation regarding high concentrations of PM10 and NO2 occurs in Krakow. For all analysed urban background stations very similar low SO2 air concentrations are observed which proves the decreasing significance of emissions from coal combustion sources.

E3S Web of Conferences, Vol. 45, Issue 00009, Jul 30, 2018

The paper presents the impact of the cleaning of a dual carriageway located in a street canyon in... more The paper presents the impact of the cleaning of a dual carriageway located in a street canyon in Krakow (Southern Poland) on the levels of the PM10 and PM2.5 air concentrations. For this purpose, representative dust samples from the analysed street were collected corresponding to the street cleaning situation, the re-entrained road dust PM10 and PM2.5 emissions were estimated in accordance with the U.S. EPA guidelines, and the particulate matter atmospheric dispersion modelling was carried out using the CALINE4 model for a selected episode of street cleaning. The modelling results were compared with the measurement results of the PM10 and PM2.5 air concentrations obtained from the air quality monitoring station (traffic type) located in the middle of this street canyon. The results of the air dispersion modelling in the canyon zone confirmed the strong impact of street cleaning on the temporary (1-hour) PM10 concentrations in the direct vicinity of the cleaned section depending on meteorological conditions. During the cleaning episode, no significant increase in the PM2.5 concentration in the air was observed.

E3S Web of Conferences, Vol. 28, Issue 01003, Jan 10, 2018

Scientific research studies conducted in various parts of the world confirm that PM10 concentrati... more Scientific research studies conducted in various parts of the world confirm that PM10 concentrations in urban air depend to a great extent on the resuspension processes of the dust deposited on the road surface. The paper presents the results of the study related to the determination of the re-entrained PM10 emissions from four selected streets of Krakow (Southern Poland) together with the assessment of its impact on air quality. Examined streets are characterised by different traffic intensity (from 500 to over 20 000 vehicles per day) and individual vehicle structure. Dust material sampling and estimation of the PM10 emission were conducted according to the U.S. EPA methodology (AP 42 Fifth Edition). Two variants of sample collection were applied: from the road surface including the area at the curb (4 streets) and from the road surface alone (1 street). The estimates of resuspended road dust emission as well as the reference values derived from the U.S. EPA guidelines were used to assess the impact of this emission on the PM10 levels in the air at the location of one of the analysed streets. This assessment was conducted using the CALINE4 mathematical model. The study showed that the PM10 emissions from the re-entrained road dust can be responsible for up to 25 % in the winter and 50 % in the summer of the total PM10 concentrations in the air near the roads.

Applied Sciences, Vol. 8, Issue 11, 2301, Nov 19, 2018

Featured Application: Yielded research results indicate that the problems of the computational gr... more Featured Application: Yielded research results indicate that the problems of the computational grid resolution in the CALMET/CALPUFF modeling system cannot be neglected during air quality impact assessment at a local scale for regulatory purposes. Decrease in grid resolution results in the underestimation of the highest maximum concentrations, which may lead to inadequate administrative decisions. Abstract: Increase in grid resolution in atmospheric non-steady-state dispersion models induces a more faithful reflection of the area surface, and thus contributes to more detailed and diversified calculation results but also significantly prolongs the calculation time. This paper presents the influence of horizontal grid resolution in the CALMET/CALPUFF modeling system on the results of air quality impact assessment in a local scale carried out for the Municipal Solid Waste Incineration (MSWI) Plant in Krakow using the maximum permissible emission of NO x. Subject to comparative analysis were four grids of the following resolutions: 100, 250, 500 and 1000 m. A direct intercomparison of air concentrations was made for 676 discrete receptors with the use of statistical indicators. On the basis of the calculations and analyses, it has been stated that, depending on the regular grid spacing, some differences in calculated concentrations can occur affecting the results of the air quality impact assessment. The highest concentrations in all computational receptors present in the given case were obtained for 100 m grid spacing. When compared to a grid of 100 m, the relatively smallest discrepancies were obtained for a grid of 250 m, with an already significantly shortened calculation time.

Geomatics and Environmental Engineering, Vol. 13, No. 2, 31-45, May 27, 2019

The exceedance of air quality standards in urban agglomerations leads local communities to take a... more The exceedance of air quality standards in urban agglomerations leads local communities to take actions that aim to improve aerosanitary conditions. For these actions to be efficient, it is essential to regularly collect accurate quantitative data that is able to characterize the degree of ambient air pollution. In order to achieve this objective, air quality monitoring systems are constantly being extended. In this paper, the usefulness of newly established air quality measuring stations in Krakow was examined. The assessment was carried out using statistical methods on the basis of the spatial and temporal variability of particulate matter (PM 10) air concentrations over the period of 2016-2017. In the analysis, meteorological data (wind directions) were applied. The main part of this assessment was a pairwise comparison of the PM 10 concentrations measured at particular stations. The differences between the average values and the Pearson correlation coefficient were considered. In order to verify the statistical significance of the obtained results, the t-Student test was conducted. The greatest absolute differences between the measured values occurred during the autumn-winter period (heating season). Notwithstanding the foregoing, a high variability was also observed among the traffic stations.

E3S Web of Conferences, Vol. 22, Issue 00149, Nov 7, 2017

The accuracy of air pollutants dispersion modelling results depends on the quality of the input d... more The accuracy of air pollutants dispersion modelling results depends on the quality of the input data, including the representativeness of the meteorological data. The paper presents the results of the AERMOD model validation using data from Tracy Power Plant experiment (Nevada, USA) with various meteorological data sources, including WRF modelling system outputs. The highest efficiency of the AERMOD model performance was found using site-specific meteorological data and the results from the WRF model. In general, the AERMOD modelling system inadequately represents the concentration levels of tracer gas (SF6) at receptors situated below the emitter height in areas of complex topography.

Environmental Protection and Natural Resources, Vol. 28, No. 2(72), 22-27, Jun 27, 2017

The paper presents the possibilities of selected functions from openair package for R programming... more The paper presents the possibilities of selected functions from openair package for R programming environment in urban air pollution assessment. Examples of data analysis were based on the measurements from continuous air quality monitoring stations in Krakow (Poland). In order to present additional functionality of this software, modeling results of back trajectories and air pollution dispersion were used. Functions and visualization methods included in openair package make scrutiny of large data sets easier and less time consuming. They allow for analysis of measurement data with the determination of general relationships between parameters, additional complex spatial analyses for back trajectories, and validation of air pollution dispersion models. Openair package is, therefore, a valuable and functional tool that can be successfully used as a support in the air quality management system.

The paper presents a comprehensive analysis of the impact of continuous casting of steel technolo... more The paper presents a comprehensive analysis of the impact of continuous casting of steel technology on air pollutant emissions in one of the Polish steelworks - Huta Katowice S.A. in Dąbrowa Górnicza. Emission sources occurring in the production process and the levels of pollutant emissions into the air were described. Implementation of continuous casting of steel brought significant changes in the production cycle in steelworks and caused an increase in the efficiency of manufacture of products. Calculated environmental effects showed a significant reduction of all pollutant emissions in the whole plant. English title: Technology of continuous casting of steel and its impact on reducing pollutant emissions from metallurgical processes.

Badania i Rozwój Młodych Naukowców w Polsce - Ochrona środowiska (red. J. Nyćkowiak, J. Leśny), Jan 1, 2017

The chapter presents exemplary results of backward trajectory calculations using the HYSPLIT mode... more The chapter presents exemplary results of backward trajectory calculations using the HYSPLIT modeling system to assess the inflow directions of selected air pollutants at the location of Krakow. The analysis was carried out using both WRF meteorological modeling results and NCEP/NCAR global reanalysis dataset. The study focused on episodes characterized by elevated concentrations of air pollutants observed at the Kurdwanow urban background station in Krakow (Southern Poland), which location was chosen as the starting point for backward trajectory calculations. Both the ventilation effects caused by a sudden change of wind speed and direction (Xaver cyclone) and stagnation of the air during winter period were presented. In order to determine long-term trends, a clustering analysis for trajectories calculated for 2015 was performed. The results indicate that elevated concentrations of PM10 are associated with inflows of air masses originating from the south and south-west (i.a. crossing the Ostrawa-Mošnov industrial zone), but this may be partially associated with the influence of local emission sources. The inflow from the North and North Sea areas is characterized by higher wind speed and is consequently associated with lower air pollutants concentrations observed at the location of Kurdwanow urban background station in Krakow.

Assessment of the impact on air quality for combustion sources should be carried out using advanc... more Assessment of the impact on air quality for combustion sources should be carried out using advanced modelling systems with chemical transformation modules taken into account, especially for the facilities characterized by significant emission of gaseous air pollutants (including SO2). This approach increases the reliability of the obtained evaluation results by modelling the formation of secondary inorganic aerosol (SIA) in the air which can substantially contribute to PM10. This paper assesses in this regard selected chemical transformation modules (MESOPUFF, RIVAD/ARM3, ISORROPIA/RIVAD) available in the CALPUFF model (v. 6.42) and its application in the atmospheric dispersion modelling of air emissions from a coal-fired large combustion plant (LCP) not equipped with a flue gas desulphurization (FGD) system. It has been proven that consideration an additional mechanism of secondary sulfate aerosol formation in aqueous phase in the ISORROPIA/RIVAD module (AQUA option) causes a significant increase in the annual average concentration of PM10 in the air compared to the other considered options, along with the calculation variant which excludes chemical transformation mechanisms. Type of the selected chemical transformation module has no significant effect on the results of modelled NO, NO2 and NOx concentrations in the air. However, it can lead to different SO2 results, especially for annual averaged, and in some points, for the hourly averaged concentrations.
English title: Assessment of the air pol lution inflow dir ect ions using the HYSPLIT model.

Air quality impact assessment is usually carried out with the application of simplified stationar... more Air quality impact assessment is usually carried out with the application of simplified stationary dispersion models, which omit the chemical transformation process of air pollutants. Omission of this effect in the calculation process increases the uncertainty of the obtained results, and hinders the decision making process, related to air quality management. The paper presents a comparison of atmospheric dispersion modeling related to pollutants emitted from high industrial emitters, performed with and without consideration of various chemical transformation modules pertaining to the formation of inorganic aerosols, available in the CALMET/CALPUFF modeling system. A mechanism of inorganic aerosol formation in a liquid phase, considered in the ISORROPIA/RIVAD+AQUA module was observed to exert strong influence on calculation results referring to concentration levels of some air contaminants. The following was found out: more than a double decrease of the annual average concentration of SO2, and even more significant increase (from 7 to 10 times) of the annual average concentration of PM10 (as a sum of primary and secondary particles) in comparison to other considered chemical transformation modules (MESOPUFF, RIVAD/ARM3, ISORROPIA/RIVAD), and a variant with a chemical transformation module switched off (without taking into account the secondary inorganic aerosol formation).

The paper discusses the role of wind speed and mixing-layer height in shaping the levels of pollu... more The paper discusses the role of wind speed and mixing-layer height in shaping the levels of pollutant concentrations in the air of Krakow (Southern Poland). The hourly averaged measurements of concentrations of selected air pollutants and wind speed values from the period of 2014-2015, recorded at two of the air quality monitoring stations within Krakow (both industrial and urban background) were used for this purpose. Temporal variability of mixing-layer height in the area of the monitoring stations was determined using numerical modelling with the CALMET model and the measurements derived from, i.a., two upper air stations. It was found that wind speed and mixing-layer height are in at least moderate agreement with the concentration values for some pollutants. For PM10, PM2.5, NO2, NOx, CO and C6H6 correlation coefficient is of negative value, which indicates that the low wind speed and low mixing-layer height may be the dominant reason for elevated concentrations of these substances in the air, especially in the winter months. Moderate but positive correlation was found between O3 concentrations and analysed meteorological parameters, proving that the availability of appropriate precursors and their inflow from the neighbouring areas have an important role in the formation of tropospheric ozone. On the other hand, in case of SO2, a weak both positive and negative correlation coefficient was obtained, depending on the period and location of the station concerned.

Preliminary analysis of the results of atmospheric dispersion modeling for dust emission from the... more Preliminary analysis of the results of atmospheric dispersion modeling for dust emission from the Katowice Steelworks (Poland) showed necessity of verification the particulate matter, lead and cadmium emission from the plant. The verification was limited to the substance emission sources influencing air pollution to the largest extent. Both scale of dust emission and its granulometric and chemical composition were re-evaluated. Further calculations of the air propagation for the pollutants were carried out and calculation results were compared with direct measurements. Thus the Katowice Steelworks impact on air quality and the level of total dust, lead and cadmium ground deposition was evaluated.
English title: Verification of dust emission from the Katowice Steelworks and range of its impact.

Continuous measurement results of selected constituent concentrations in the gases emitted to the... more Continuous measurement results of selected constituent concentrations in the gases emitted to the air during the coke wet quenching process were presented and discussed in the paper. The measurements were carried out for the standard wet quenching tower. The research covered such substances as carbon dioxide, carbon monoxide, hydrogen sulfide, nitrogen oxide, nitrogen dioxide and a total content of hydrocarbons and hydrogen (combustible gases). Changeability of the substance concentrations depending of the quenching process duration was analyzed. Among other things the beginning of these substances formation, appearance of the maximum and the range of observed concentrations were taken into consideration. Main reactions reactions occurring in the process and mechanisms of the flue gas component formations were presented as well.
English title: Changeability of selected pollutant concentrations in flue gases from the coke wet quenching process.