On the Fractal Mechanism of Interrelation Between the Genesis, Size and Composition of Atmospheric Particulate Matters in Different Regions of the Earth

Experimental data from the National Air Surveillance Network of Japan from 1974 to 1996 and from inde-pendent measurements performed simultaneously in the regions of Ljubljana (Slovenia), Odessa (Ukraine) and the Ukrainian “Academician Vernadsky” Antarctic station (64o15W;65o15S), where the air elemental composition was determined by the standard method of atmospheric particulate matter (PM) collection on nucleopore filters and subsequent neutron activation analysis, were analyzed. Comparative analysis of dif-ferent pairs of atmospheric PM element concentration data sets, measured in different regions of the Earth, revealed a stable linear (on a logarithmic scale) correlation, showing a power law increase of every atmos-pheric PM element mass and simultaneously the cause of this increase – fractal nature of atmospheric PM genesis. Within the framework of multifractal geometry we show that the mass (volume) of atmospheric PM elemental components has a log normal distribution, which on a logarithmic scale with respect to the random variable (elemental component mass) is identical to normal distribution. This means that the parameters of two-dimensional normal distribution with respect to corresponding atmospheric PM-multifractal elemental components measured in different regions, are a priory connected by equations of direct and inverse linear regression, and the experimental manifestation of this fact is the linear correlation between the concentra-tions of the same elemental components in different sets of experimental atmospheric PM data.

Distribution and Accumulation of Major and Trace Elements in Gypsum Samples from Lignite Combustion Power Plant

Flue gas containing volatile elements, fine fly ash particulates not retained by particle control devices, and limestone are the most important sources of trace and major elements (TMEs) in wet flue gas desulphurization (WFGD) gypsum. In this study, samples of gypsum slurry were separated into fine and coarse fractions. Multi-elemental analysis of 45 elements in the different size fractions of gypsum, slurry waters and lignite were performed by k0-INAA (k0-instrumental neutron activation analyses). The study found that the volatile elements (Hg, Se and halogens) in the flue gas accumulate in the fine fractions of gypsum. Moreover, the concentrations of most TMEs are considerably higher in the fine fractions compared to the coarse fractions. The exceptions are Ca and Sr that primarily originate from the limestone. Variations of TMEs in the finer fractions are dependent on the presence of CaSO4·2H2O that is the main constituent of the coarse fraction. Consequently, the content of TMEs in the fine fraction is highly dependent on the efficiency of separating the fine fraction from the coarse fraction. Separation of the finer fraction, representing about 10% of the total gypsum, offers the possibility to remove effectively TMEs from WFGD slurry.

Temperature Fractionation (TF) of Hg Compounds in Gypsum from Wet Flue Gas Desulfurization System of the Coal Fired Thermal Power Plant (TPP)

Gypsum from the wet flue gas desulfurization system of the lignite fired thermal power plant Sostanj, Slovenia, can efficiently retain mercury (Hg), of which most is contained in finer gypsum fractions, with concentrations above 10 kg-1. The aim of this work was to identify and study the temperature stability of Hg species in gypsum by a temperature fractionation (TF) method. A self-constructed apparatus was used that consisted of an electrical furnace for controlled heating up to 700°C, with a heating rate of 2.2°C·min-1, and an AAS detector with Zeeman background correction. The pattern of Hg release during temperature increase depends highly on the matrix/substrate in which it is contained. Based on spiking gypsum with known Hg compounds we concluded that the largest proportion of Hg in gypsum belongs to Hg-Cl and Hg-Br compounds appearing at 160°C to 200°C, followed by smaller amounts of HgO, HgS and Hg sulfates appearing at 300°C and 450°C. Further development of methodology for identifying Hg species would require identification of the decomposition fragments of Hg and other compounds, complemented by a better understanding of Hg reactivity at higher temperatures.