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EN
Samples of PM10 and PM2.5 fractions were collected between the years 2010 and 2013 at the urban area of Krakow, Poland. Numerous types of air pollution sources are present at the site; these include steel and cement industries, traffic, municipal emission sources and biomass burning. Energy dispersive X-ray fluorescence was used to determine the concentrations of the following elements: Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, As and Pb within the collected samples. Defi ning the elements as indicators, airborne particulate matter (APM) source profiles were prepared by applying principal component analysis (PCA), factor analysis (FA) and multiple linear regression (MLR). Four different factors identifying possible air pollution sources for both PM10 and PM2.5 fractions were attributed to municipal emissions, biomass burning, steel industry, traffic, cement and metal industry, Zn and Pb industry and secondary aerosols. The uncertainty associated with each loading was determined by a statistical simulation method that took into account the individual elemental concentrations and their corresponding uncertainties. It will be possible to identify two or more sources of air particulate matter pollution for a single factor in case it is extremely difficult to separate the sources.
EN
Samples of PM2.5 fraction (particles with aerodynamic diameter ≤2.5 mu m) of air particulates were collected in winter 2011 and summer 2012 in Cracow, Poland. The concentrations of PM2.5 were 50 ±23 mu g/m3 (wintertime) and 16 ± 6 mu g/mV (summertime). The energy dispersive X-Ray fluorescence method was used for the determination of the concentrations of PM2.5-related elements. Principal component analysis and multilinear regression analysis were used to determine source contributions to ambient concentrations of PM2.5. In wintertime, the sources of air pollution were identified as municipal emission, steel and ferrous industry (49.2%), traffic (37.8%) and other, not identified sources (13%), whereas during summer, they were traffic (53%), steel and ferrous industry (18%), and not identified sources (29%).
EN
The scientific interest in air pollution comes from its influence on human health, the condition of cultural heritage and climate. The PM2.5 fraction (particles of a diameter of 2.5 mm or below), indirectly, has a significant impact on health which is associated with respiratory tract and blood vessel related diseases. However, not only the size, but also the content of the particles has a significant meaning. To determine the particulate matter contents, elemental analysis can be performed using numerous techniques, the most important of which is X-ray fluorescence. In this study, samples of PM2.5 fraction collected in Krakow, Poland were analyzed. The X-ray fluorescence method was used to perform elemental analysis. The gravimetric method was applied to determine the concentration of the PM2.5 fraction. Low detection limits of individual elements and precision of the X-ray fluorescence method were determined. The concentrations of the following elements: Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Br, Rb, Sr and Pb in the PM2.5 fraction samples collected in Krakow were evaluated. The homogeneity of the samples was also estimated. The concentrations of PM2.5 fraction collected in the summer of 2013 were in the range of 6–23 ng/m3. The concentrations of PM2.5 fraction collected in the winter of 2013 were in the range of 26–171 ng/m3. The precision of the method was found to be below 1% for elements with high concentration in the sample and 6–8 % for trace elements.
EN
The carbon-in-leach (CIL) process is one the most efficient methods of gold recovery from gold bearing ores. The efficiency of the leaching process greatly depends on the flow structure created by mechanical agitation (in some cases air agitation) in the leaching tanks. Residence time distribution (RTD) measurement was conducted in the CIL section of a gold processing plant in order to determine the flow structure in the first tank using the 131I radioactive tracer. The shape of the experimental data revealed that the flow behaviour in the tank was close to an ideal mixer. Modelling of the experimental data, however, revealed that the tank was not behaving as a single perfect mixer, but consisted of two mixing zones. The flow structure in the tank was best described by the “perfect mixers with exchange” model consisting of two mixing zones. The model allowed the determination of flow parameters including the mean residence time, flow rate and volumes of the mixing zones.
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