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Characterization of the chemical composition of the tar produced in the gasification of biomass
Mahelová, Zora ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Biomass is a renewable source of energy and represents an acceptable alternative to fosil fuels. Usable methods of energetic use of biomass are combustion and gasification. Main interest is focused on gasification in last years. Gasification is based on conversion of organic material to usable gaseous product called syngas, which can be used as a fuel for energy production. Large amount of tar is formed as a by-product of incineration and gasification of biomass. Tar is composed by various mixture of organic substances, has a negative effect on operating conditions and is a potential threat to environment. Experimental part of this study was focused on analysis of tar obtained by gasification of various kind of biomass. Selected groups of hydrocarbons and oxygen compounds were identified in analysed samples. Individual biomass samples were compared regarding to determined relative content of selected substances. Analysis was done by complete twodimensional gas chromatography with mass spectrometric detection (GCxGC/TOF-MS).
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Determination of organic compounds in the tar
Magdechová, Andrea ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
The diploma thesis deals with determination of organic compounds in the tar. It is focussed on polycyclic aromatic hydrocarbons, BTEX and n-alkanes. The tar samples were collected by Faculty of Mechanical Engineering BUT Brno during two days and under diferent conditions of biomass gasification. The samples were filtrated and refined using column chromatography on silicagel sorbent. Gas chromatography with mass detection was chosen to determine polycyclic aromatic hydrocarbons and gas chromatography with flame ionisation detection was chosen to determine BTEX and n-alkanes.
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The Application of Separation Techniques Based on Gas and Liquid Chromatography with Different Types of Detectors for the Determination of Biologically Active Compounds and Selected Xenobiotics
Mravcová, Ludmila ; Hajšlová, Jana (referee) ; Kráčmar, Stanislav (referee) ; Chýlková,, Jaromíra (referee) ; Vávrová, Milada (advisor)
This work deals with the using and application of separation techniques for analysis of polymers degradation and polycyclic aromatic hydrocarbons. Thereby this work is separated to two special parts. In the first part, the degradation properties of synthetic biopolymers based on lactic acid, gylcolic acid and poly(ethyleneglycol) PLGA-PEG-PLGA and ITA-PLGA-PEG-PLGA-ITA (modified by itaconic acid) were studied. These copolymers (firstly their thermosensitive hydrogels) should be used for therapy of fractures in orthopedy (as adhesives). Therefore, the sol-gel and gel-sol phase diagrams were determinated for selected samples of copolymers. The samples forming gel at 37 C was used for other study. Polymer samples were depredated in phosphate buffer at 37°C. The degradation process of physical hydrogels was described by the decrease of molecular weight and the increase of concentration lactic acid and glycolic acid in phosphate buffer. The obtained results confirmed that the degradation of polymer modified by itaconic acid is faster process than no modified polymer and polymers with lower ratio PLGA/PEG degrade also faster than lower ration PLGA/PEG. The influence of pH it was also tested. The rate of degradation of polymers was follow pH 4,0
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Source apportionment of PAH in middle Europe
Lhotka, Radek
The diploma thesis deals with the determination of sources of polycyclic aromatic hydrocarbons (PAH) and the changes in the PAH concentrations during the last 11 years, from 2006 to 2016. The data were sampled at National Atmospheric Observatory in Košetice, a representative station for the Central European Region. Multidimensional statistical methods as Positive Matrix Factorization (PMF), conditional bivariate probability function (CBPF), and Potential Source Contribution Function (PSCF) were used for data analyses. In the first part, the changes in concentrations of the four specific PAH, Benzo(a)pyrene (BaP), Fluoranthene (FLA), the sums of all the PAH (SUMA), and the Toxical Equivalent (TEQ) was studied. The highest concentration of all four specific PAH was detected at the beginning of the studied period. The immission limit for BaP was not exceeded. Statistically significant decreasing trend for BaP, TEQ, and SUMA PAH was identified. Second part of the thesis studied the PAH source apportionment. The study proved that the station was strongly influenced by the local domestic heating on one hand, and long-distance transportation from the west, and specifically from the northwest on the other hand. The influence of long-distance transport has an increasing trend over time, vice-versa for the...
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The relation between microbial diversity and biodegradation of organic pollutants in soils
Adámek, Michael ; Svobodová, Kateřina (advisor) ; Matyska Lišková, Petra (referee)
This work sums up the knowledge of the currently studied microorganisms capable of degradation of organic compounds contaminating soil and of the impact of biodiversity on biodegradation efficiency. As documented in many studies effective soil remediation can be achieved by mixed-species consortia isolated from polluted soils. However, use of these cultures for bioaugumentation requires further research on their influence on the biodiversity of autochthonic soil microflora. Though bioaugumentation provably affects bioremediation effectivity no ideal carrier for microbes has been found yet that would provide survival of the introduced organisms in the competitive soil environment. Next, selection of suitable bioaugumentation agents should be based on previous analyses of autochthonic microbes in the targeted contaminated soils. Further, this work shows that the presence of key species might be more important for the biodegradation efficiency than biodiversity of soil microflora. Biodiversity is more related to the functionality of soil ecosystems which can be affected by the presence of contaminants leading to positive selection of taxa capable of pollutant degradation. However, there are just a few studies on the relationship between biodiversity and degradation of pollutants. Its further research...
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Source apportionment of PAH in middle Europe
Lhotka, Radek ; Zíková, Naděžda (advisor) ; Mikeš, Ondřej (referee)
The diploma thesis deals with the determination of sources of polycyclic aromatic hydrocarbons (PAH) and the changes in the PAH concentrations during the last 11 years, from 2006 to 2016. The data were sampled at National Atmospheric Observatory in Košetice, a representative station for the Central European Region. Multidimensional statistical methods as Positive Matrix Factorization (PMF), conditional bivariate probability function (CBPF), and Potential Source Contribution Function (PSCF) were used for data analyses. In the first part, the changes in concentrations of the four specific PAH, Benzo(a)pyrene (BaP), Fluoranthene (FLA), the sums of all the PAH (SUMA), and the Toxical Equivalent (TEQ) was studied. The highest concentration of all four specific PAH was detected at the beginning of the studied period. The immission limit for BaP was not exceeded. Statistically significant decreasing trend for BaP, TEQ, and SUMA PAH was identified. Second part of the thesis studied the PAH source apportionment. The study proved that the station was strongly influenced by the local domestic heating on one hand, and long-distance transportation from the west, and specifically from the northwest on the other hand. The influence of long-distance transport has an increasing trend over time, vice-versa for the...
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The relation between microbial diversity and biodegradation of organic pollutants in soils
Adámek, Michael ; Svobodová, Kateřina (advisor) ; Matyska Lišková, Petra (referee)
This work sums up the knowledge of the currently studied microorganisms capable of degradation of organic compounds contaminating soil and of the impact of biodiversity on biodegradation efficiency. As documented in many studies effective soil remediation can be achieved by mixed-species consortia isolated from polluted soils. However, use of these cultures for bioaugumentation requires further research on their influence on the biodiversity of autochthonic soil microflora. Though bioaugumentation provably affects bioremediation effectivity no ideal carrier for microbes has been found yet that would provide survival of the introduced organisms in the competitive soil environment. Next, selection of suitable bioaugumentation agents should be based on previous analyses of autochthonic microbes in the targeted contaminated soils. Further, this work shows that the presence of key species might be more important for the biodegradation efficiency than biodiversity of soil microflora. Biodiversity is more related to the functionality of soil ecosystems which can be affected by the presence of contaminants leading to positive selection of taxa capable of pollutant degradation. However, there are just a few studies on the relationship between biodiversity and degradation of pollutants. Its further research...
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Characterization of the chemical composition of the tar produced in the gasification of biomass
Mahelová, Zora ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Biomass is a renewable source of energy and represents an acceptable alternative to fosil fuels. Usable methods of energetic use of biomass are combustion and gasification. Main interest is focused on gasification in last years. Gasification is based on conversion of organic material to usable gaseous product called syngas, which can be used as a fuel for energy production. Large amount of tar is formed as a by-product of incineration and gasification of biomass. Tar is composed by various mixture of organic substances, has a negative effect on operating conditions and is a potential threat to environment. Experimental part of this study was focused on analysis of tar obtained by gasification of various kind of biomass. Selected groups of hydrocarbons and oxygen compounds were identified in analysed samples. Individual biomass samples were compared regarding to determined relative content of selected substances. Analysis was done by complete twodimensional gas chromatography with mass spectrometric detection (GCxGC/TOF-MS).
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The Application of Separation Techniques Based on Gas and Liquid Chromatography with Different Types of Detectors for the Determination of Biologically Active Compounds and Selected Xenobiotics
Mravcová, Ludmila ; Hajšlová, Jana (referee) ; Kráčmar, Stanislav (referee) ; Chýlková,, Jaromíra (referee) ; Vávrová, Milada (advisor)
This work deals with the using and application of separation techniques for analysis of polymers degradation and polycyclic aromatic hydrocarbons. Thereby this work is separated to two special parts. In the first part, the degradation properties of synthetic biopolymers based on lactic acid, gylcolic acid and poly(ethyleneglycol) PLGA-PEG-PLGA and ITA-PLGA-PEG-PLGA-ITA (modified by itaconic acid) were studied. These copolymers (firstly their thermosensitive hydrogels) should be used for therapy of fractures in orthopedy (as adhesives). Therefore, the sol-gel and gel-sol phase diagrams were determinated for selected samples of copolymers. The samples forming gel at 37 C was used for other study. Polymer samples were depredated in phosphate buffer at 37°C. The degradation process of physical hydrogels was described by the decrease of molecular weight and the increase of concentration lactic acid and glycolic acid in phosphate buffer. The obtained results confirmed that the degradation of polymer modified by itaconic acid is faster process than no modified polymer and polymers with lower ratio PLGA/PEG degrade also faster than lower ration PLGA/PEG. The influence of pH it was also tested. The rate of degradation of polymers was follow pH 4,0
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Determination of organic compounds in the tar
Magdechová, Andrea ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
The diploma thesis deals with determination of organic compounds in the tar. It is focussed on polycyclic aromatic hydrocarbons, BTEX and n-alkanes. The tar samples were collected by Faculty of Mechanical Engineering BUT Brno during two days and under diferent conditions of biomass gasification. The samples were filtrated and refined using column chromatography on silicagel sorbent. Gas chromatography with mass detection was chosen to determine polycyclic aromatic hydrocarbons and gas chromatography with flame ionisation detection was chosen to determine BTEX and n-alkanes.
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