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Effect of ESP on distribution and chemical composition of particles from biomass combustion
Preisler, Lukáš ; Köbölová, Klaudie (referee) ; Adamec, Vladimír (advisor)
Biomass combustion causes a significant number of particles that, released into the atmosphere, negatively affect human health. Knowledge of the size and composition of the particles is essential for possible flue gas separation by electrostatic precipitation technology. This technology is developed and used in large power plants, but the electrostatic precipitation in domestic boilers is rare. This work describes the methods of fine particle formation and their size distribution and composition. Measurement methods of chemical composition and the size distribution are provided. According to a review, the effect of electrostatic precipitator on size distribution and chemical composition is discussed. In the experimental part, fine particles were sampled from the flue gas of a domestic wood pellet boiler containing an experimental electrostatic precipitator. Due to operational reasons, the electrostatic precipitator did not run during sampling. Flue gas condensed on the inner surface of the flue. The particles were sampled on filters at the beginning and the end of the flue. The filter was analyzed on an electron microscope.
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Effect of ESP on distribution and chemical composition of particles from biomass combustion
Preisler, Lukáš ; Köbölová, Klaudie (referee) ; Adamec, Vladimír (advisor)
Biomass combustion causes a significant number of particles that, released into the atmosphere, negatively affect human health. Knowledge of the size and composition of the particles is essential for possible flue gas separation by electrostatic precipitation technology. This technology is developed and used in large power plants, but the electrostatic precipitation in domestic boilers is rare. This work describes the methods of fine particle formation and their size distribution and composition. Measurement methods of chemical composition and the size distribution are provided. According to a review, the effect of electrostatic precipitator on size distribution and chemical composition is discussed. In the experimental part, fine particles were sampled from the flue gas of a domestic wood pellet boiler containing an experimental electrostatic precipitator. Due to operational reasons, the electrostatic precipitator did not run during sampling. Flue gas condensed on the inner surface of the flue. The particles were sampled on filters at the beginning and the end of the flue. The filter was analyzed on an electron microscope.
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Aerosol size distribution of PAH in urban atmosphere
Bendl, Jan ; Hovorka, Jan (advisor) ; Mikuška, Pavel (referee)
The aim of the study was to determine the 13 health risk PAHs (phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene, ideno(1,2,3-cd)perylene and coronene; c-PAU highlighted) in the fractions of size-segregated aerosol of the urban air in Ostrava (2012, 2014) and Mlada Boleslav (2013) at low temperatures in winter, and to verify experimentally a sampling artifact, i.e., to quantify PAHs in the gas phase. For the particle size separation high-volume cascade impactor Hi-Vol BGI 900 was used. PAHs were determined by HPLC-FLD/PDA. In Ostrava in 2012 during the winter inversion (up to -25 řC), mean concentration of 13 PAHs in aerosol was 432 ng.m-3 ; in fraction 10 - 1 µm 119 ng.m-3 , 1 - 0,5 µm 185 ng.m-3 , 0,5 - 0,17 µm 91 ng.m-3 , in fraction < 0,17 µm 37 ng.m-3 and in the gaseous phase of min. 40 ng.m-3 . In the most unfavorable day 2. 2. 2012 (-18.6 ř C) reached the 24-hour average of 13 PAHs 890 ng.m-3 , the sum of carcinogenic PAHs 237 ng.m-3 and benzo(a)pyrene 32.3 ng.m-3 . An irregular and different decline of PAHs concentrations after inversion was measured: in fraction 1 - 10 µm 2.8 times, 0.5 - 1 µm 4.2 times, 0.5 - 0.17 µm 4 times and for <0.17 µm up to 7.6 times....
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Atmospheric aerosol: physical-chemical characterisation and source apportionment
Leoni, Cecilia ; Hovorka, Jan (advisor) ; Ždímal, Vladimír (referee) ; Lammel, Gerhard (referee)
Atmospheric aerosol is a ubiquitous component of the Earth atmosphere. By mass, aerosol natural sources override anthropogenic ones, the latter constituting less than 5% to the total aerosol loading (Jaenicke, 2008). Nevertheless, in urban environment the contribution can increase to 80-90%. Since anthropogenic sources are mostly associated with high temperature processes, urban aerosol number size distribution is usually dominated by ultrafine particles - UFPs (d<100 nm). The UFPs have the highest surface/mass ratios among aerosol particles and bond the highest pollutant loading as per particle mass. Additionally, the UFPs exhibit the highest deposition efficiency in deep region of the human respiratory tract. Therefore, this study focuses to urban aerosol particle spatial-temporal, physical and chemical characterization and source apportionment with special emphasis to the UFPs. The first study in residential district of Ostrava-Radvanice and Bartovice, an air pollution hot spot in Europe, identified industry being dominant sources of UFPs. High particle number concentrations (NC) were measured at the hot spot, with peaks up to 1.4x105 particles cm-3 during plume events, i.e. downwind an industrial facility. The plume-originating UFPs were mostly composed of 19−44 nm nanoparticles heavily...
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Aerosol size distribution of PAH in urban atmosphere
Bendl, Jan ; Hovorka, Jan (advisor) ; Mikuška, Pavel (referee)
The aim of the study was to determine the 13 health risk PAHs (phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene, ideno(1,2,3-cd)perylene and coronene; c-PAU highlighted) in the fractions of size-segregated aerosol of the urban air in Ostrava (2012, 2014) and Mlada Boleslav (2013) at low temperatures in winter, and to verify experimentally a sampling artifact, i.e., to quantify PAHs in the gas phase. For the particle size separation high-volume cascade impactor Hi-Vol BGI 900 was used. PAHs were determined by HPLC-FLD/PDA. In Ostrava in 2012 during the winter inversion (up to -25 řC), mean concentration of 13 PAHs in aerosol was 432 ng.m-3 ; in fraction 10 - 1 µm 119 ng.m-3 , 1 - 0,5 µm 185 ng.m-3 , 0,5 - 0,17 µm 91 ng.m-3 , in fraction < 0,17 µm 37 ng.m-3 and in the gaseous phase of min. 40 ng.m-3 . In the most unfavorable day 2. 2. 2012 (-18.6 ř C) reached the 24-hour average of 13 PAHs 890 ng.m-3 , the sum of carcinogenic PAHs 237 ng.m-3 and benzo(a)pyrene 32.3 ng.m-3 . An irregular and different decline of PAHs concentrations after inversion was measured: in fraction 1 - 10 µm 2.8 times, 0.5 - 1 µm 4.2 times, 0.5 - 0.17 µm 4 times and for <0.17 µm up to 7.6 times....
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How important are cannibalism and intraguild predation for aquatic insect communities?
PEROUTKA, Miroslav
Cannibalism and intraguild predation in the communities of aquatic insects are reviewed. Special attention is paid to the relationship of predator and prey size and to the impact of cannibalism and intraguild predation on population dynamics and individual life histories. Detection of prey and predator and antipredator strategies are also reviewed. The review is complemented by laboratory experiments on selected species of dragonflies.
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