Vyhodnocení rizik vlivu sekundární resuspenze prachových částic z termicky aktivních odvalů.

Abstract

In the past, several tens of dumps, which are the remains of black coal mining, originated in the Ostrava region. In earlier years, there were no technologies known to get rid of coal-based dirt, so a mixture of coal and tailings was bloated. This has often resulted in the self-extinguishing of ditches, some of which are still active today. Thermally active dumps adversely affect the atmosphere through inorganic, organic and gaseous emissions. In the dissertation the research focused on selected active dumps, namely the Ema, Hedvika and Hermanice. The dissertation deals with the measurement of selected toxic metals (AS, Cd, Cr, Cu, Ni, Pb, V and Zn) on PMx, soil and green masses (leaves) from July 2017 to April 2018 and also the creation of new collection devices PMx and PAHs. Toxic metals in the soil were assessed according to the methodological guidelines of the Ministry of the Environment - Pollution Indicators and further evaluated using the geoaccumulation index. According to the pollution indicator of the Ministry of the Environment, the arsenic limit is 5–15 × exceeded on all thermally active dumps, the other metals are below the limit. For the geoaccumulation index, all values show the first stage (unpolluted to moderately contaminated), only the sample from the dumps Hermanice shows a degree of arsenic of two (slightly contaminated). At the dumps of Hedvika and Hermanice the most frequent particles are 10-25 μm in the percentage of 25,2–25,4 %. Toxic metals on PMx were most represented at Hermanice. The highest measured concentrations were analyzed at Cu = 429 mg kg-1, V = 239 mg kg-1 and As = 223 mg kg-1. The highest concentrations of toxic metals in Zn (164 mg kg-1), V (135 mg kg-1) and Pb (89 mg kg-1) and in the soil Ema and Cr (187 mg kg-1). Green matter (leaves) show the largest difference in washed and unblended samples, where Zn (169 mg kg-1) from dumps Hermanice and Hedvika Cr sample (16 mg kg-1), with other metals ranging from 1-10 mg kg-1 dry matter. SEM analyzes were also carried out in the study, which showed that the toxic metal contained only the Ema (V = 0.20 % wt) and the Hermanice (Cr = 2.01 % wt) in the analyzed samples.