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PL
Prezentowane badania miały na celu rozpoznanie stężeń submikronowego pyłu (PM1) i związanego z nim węgla organicznego (OC) i elementarnego (EC) w sali wykładowej i tzw. laboratorium studenckim. W pracy omówiono zmienność 24-godzinnych stężeń PM1, OC i EC w obu pomieszczeniach (I, ang. indoor) oraz w powietrzu atmosferycznym (O, ang. outdoor), a także przeanalizowano stosunek I do O. Na przełomie wiosny i lata, niezależnie od lokalizacji (Gliwice – laboratorium studenckie, Warszawa – sala wykładowa), stężenie węgla elementarnego (EC) i organicznego (OC) wewnątrz sal dydaktycznych kształtowała intensywność migracji tych zanieczyszczeń wraz z powietrzem atmosferycznym. Tym samym można uznać, że w żadnym z badanych pomieszczeń dydaktycznych nie występuje istotne źródło OC i EC. Mimo to należy zauważyć, że warunki sprzyjające sorpcji różnych zanieczyszczeń, w tym zwłaszcza związków organicznych tworzących grupę OC na cząstkach pyłu, zmieniają się dynamicznie w czasie i przestrzeni. Wydaje się, że w innym okresie pomiarowym, na przykład w zimie, kiedy wietrzenie sal jest rzadsze a pył atmosferyczny ma inny skład, kumulacja zanieczyszczeń, w tym OC, wewnątrz sal może być większa niż w okresie ciepłym.
EN
The research presented herein aimed at recognition of submicrone particulate matter concentration as well as organic (OC) and elemental (EC) carbon bound to it in a lecture room and students’ laboratory. The 24-h variability of PM1, OC and EC concentration in both rooms were also discussed along with I : O ratio. In the analysed period – the turn of spring and summer – independent of the location (Gliwice – students’ laboratory, Warsaw – lecture room) the indoor concentration of elemental carbon EC was conditioned by the intensity of those contaminants migration along with atmospheric air. Because of this, it can be concluded that in neither of the rooms there was an important source of OC and EC. However, it should be noted, that conditions favourable for different contaminant sorption, in particular those belonging to OC bound to particulate matter, vary in time and space. It is expected, that for other measurement period – for instance in winter, when rooms are ventilated seldom and PM has different composition, the cummulation of indoor contaminants, including OC, may be higher than for warm period.
EN
The aim of this research was to assess the content and composition of the pollutants emitted by domestic central heating boilers equipped with an automatic underfeed fuel delivery system for the combustion chamber. The comparative research was conducted. It concerned fuel properties, flue gas parameters, contents of dust (fly ash) and gaseous substances polluting the air in the flue gases emitted from a domestic CH boiler burning bituminous coal, pellets from coniferous wood, cereal straw, miscanthus, and sunflower husks, coniferous tree bark, and oats and barley grain. The emission factors for dust and gaseous air pollutants were established as they are helpful to assess the contribution of such boilers in the atmospheric air pollution. When assessing the researched boiler, it was found out that despite the development in design and construction, flue gases contained fly ash with a significant EC content, which affected the air quality.
PL
Celem pracy badawczej była ocena ilości i składu substancji zanieczyszczających emitowanych przez kotły małej mocy, wyposażone w samoczynny podajnik paliwa do komory spalania. Przeprowadzono badania porównawcze właściwości paliw, parametrów spalin, zawartości pyłu (popiołu lotnego) i gazowych substancji zanieczyszczających powietrze w emitowanych spalinach z kotła CO małej mocy spalającego węgiel kamienny (ekogroszek), pelety z drewna drzew iglastych, ze słomy zbożowej, z miskanta, z łusek słonecznika, korę drzew iglastych, ziarno owsa i ziarno jęczmienia. Ustalono wskaźniki emisji pyłu i gazowych substancji zanieczyszczających powietrze, pomocnych w ocenie udziału tego rodzaju kotłów w zanieczyszczeniu środowiska. Oceniając badany kocioł stwierdzono, że mimo osiągniętego postępu w konstrukcji, spaliny zawierają popiół lotny, ze znaczną zawartością węgla EC (black carbon), w ilości wpływającej na jakość powietrza.
EN
The analysis of elemental composition of ambient dust can help not only evaluate the environmental and health effects due to the air pollution but also identify emission sources. However, the whole number of projects and studies on concentrations and elemental composition of ambient (especially fine) dust hardly concern these issues in Eastern Europe. Neither is the chemical (and elemental) composition of the submicron ambient dust in Poland well recognized. There is also a shortage of data from long-term and parallel studies of the elemental composition of separate dust fractions. In the heavily polluted areas, the elemental composition of atmospheric aerosol and the dependence of elemental composition of particles on their size can appear essential for analyzing the toxicity of dust and its environmental effects. This study presents the results of determination and comparison of the elemental composition of four fractions of ambient dust in Zabrze (Poland), an urban area typical of the exposure of the Upper-Silesian Agglomeration population to the polluted air. The samples of the four dust fractions (fine: ≤1 µm – PM1, 1–2.5 µm – PM1-2.5, coarse: 2.5–10 µm – PM2.5-10, and 10–40 µm – PM10-40,) were collected during eight months (January–August 2009) with the use of a DEKATI-PM10 cascade impactor. All the dust samples (204 samples) were analyzed using a PANalytical Epsilon 5 spectrometer (EDXRF – energy dispersive X-Ray fluorescence spectroscopy). The minimum, maximum and average concentrations, for winter (January–April, heating season) and summer (May–August, non-heating season), of 38 elements from each of the four examined dust fractions were calculated. The influence of anthropogenic sources on the ambient concentrations of elements from each dust fraction was determined by analyzing the enrichment factors (EF). The strength of linear relationships (Pearson’s linear correlation coefficients) between each pair of elements was determined separately for fine and coarse dust. The highest ambient concentrations were assumed by two nonmetals – sulfur and chlorine; their concentrations were significantly lower in summer than in winter. Both sulfur and chlorine were mainly bound onto the finest particles. Their share in the coarse dust, even in summer, was small. They came from anthropogenic sources. Ambient, typical crustal, Si, Al, Fe, Mg, K, Ca, Ti, Sr, Rb in Zabrze came from natural sources regardless of the fraction they were bound to. Small seasonal variations in ambient concentrations of these elements or some of the concentrations higher in summer than in winter confirmed the fact. A significant portion of the mass of the crustal elements, especially of Al, Si and Fe, was concentrated in the coarse fractions. However, the mass distribution among the dust fractions indicates some of them (K, Ca, Mg, Rb, Sr) as coming partly from anthropogenic sources. It particularly concerns their part bound to fine dust in winter. The mass contribution of crustal matter to ambient dust was about 6.8 in winter and 9.7% in summer; the contribution to PM1 was half of it. Almost all remaining 27 elements (except for Mn, Zn, Ge, Sb, La) had the ambient concentrations not greater than 100 ng m-3, usually higher in winter. The average mass shares of each of these 27 elements in PM1, PM1-2.5, PM2.5-10, and PM10-40, were different and depended on the season of a year. Co, Cu, Zn, Pb and As were cumulated mostly in fine dust, while V, Mn, Co, Cr, Ni, Ag, Cd and Ba in coarse dust. The former, in fine dust, were assumed to be rather of anthropogenic origin and closely associated with combustion. The later originated partly from combustion (especially in winter) but their greater part was secondary and came from road dust. The largest contributors to the mass of the elements in fine dust in Zabrze are domestic furnaces and car engines, i.e. combustion of fossil fuels, biomass, and waste. The possible effect of industrial sources was also identified. The elemental composition of coarse dust is due to re-suspension of soil and road dust, and to a lesser extent, to municipal emission.
PL
Badano szybkość redukcji Fe(III)edta przez ditionin sodowy, Na(2)S(2)O(4) w zależności od: stosunku początkowych stężeń reagentów [Na(2)S(2)0(4)]o/[Fe(III)edta]o = 0,1:1; 0,3:1; 0,5:1 oraz 0,7:1, temperatury - 20, 40, 60, 80°C, pH roztworu - 3, 5, 7, 9 i początkowego stężenia chelatu żelazowego [Fe(III)edta]o = 0,005; 0,010; 0,050 i 0,100 mol/dm3. Pomiary prowadzono w okresowym reaktorze szklanym o pojemności 300 cm3. Stężenie jonów żelaza(III) oznaczano spektrofotometryczną metodą ortofenantrolinową. Wszystkie pomiary miały analogiczny przebieg - następowała bardzo szybka redukcja jonów żelaza(lll) w początkowych sekundach procesu, do poziomu zależnego jedynie od stosunku początkowych stężeń reagentów. Dla [Na(2)S(2)0(4)]o/[Fe(III)edta]o = 0,7:1 uzyskano całkowitą redukcję Fe(III)edta do Fe(II)edta. Pozostałe przebadane parametry nie miały wpływu na szybkość procesu redukcji
EN
The rate of Fe(III)edta reduction by sodium dithionite was investigated according to: ratio of initial reagents concentrations, [Na(2)S(2)0(4)]o/[Fe(III)edta]0 = 0.1:1; 0.3:1; 0.5:1 and 0.7:1, temperature - 20, 40, 60 and 80°C, solution pH -3,5,1 and 9, initial concentration of ferric chelate, [Fe(III)edta]0 = 0.005; 0.010; 0.050 and 0.100 mol/dm3. A periodic glass reactor of 300 cm3 volume was used. Concentrations of ferrous ions were determinated by o-fenanthroline method. Ali runs had the similar character. Ferric ions were reduced during first few seconds to a level depended from the initial ratio of reagents concentrations. Only for, [Na(2)S(2)0(4)]o/[Fe(III)edta]o = 0.7:1 run, Fe(III)edta was completely reduced to Fe(III)edta. Other investigated parameters had no influence on the Fe(II)edta process
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