Měření emisí ultrajemných částic z malých spalovacích zařízení se zřetelem na nové poznatky z výzkumu bezpečnosti nanočástic

Abstract

The world today is facing a global problem of air pollution and its adverse impacts on human health. Total suspended particles (TSP) in the atmosphere influence man much more than other harmful substances in the same environment. In the nineties, a significant improvement in air quality in the Czech Republic was achieved. However, many, particularly transport and industry heavily loaded areas (e.g. some Moravian-Silesian regions), still exceed the value limits for the protection of public health. Sources of TSP in ambient air are mainly from combustion processes. These sources are important agents in the production of TSP of small combustion equipment (SCE). The SCE problem is the low height of the chimney, which causes an accumulation of solid pollutants in the breathing zone of the population, and the fact that these devices have virtually no exhaust gas purification (filters), and do not operate similar supervisory and regulatory frameworks as large combustion sources of air pollution, whose parts are controlled continuously. From a health perspective, there is a close link in the quantitative relationship between exposure to high concentrations of PM10 and PM2.5 and the growing number of illnesses and deaths [3]. Particles of smaller size may be more risky than larger particle sizes, as they penetrate deeper into the respiratory system. It was found [2],[57] that the ultrafine particles (particles smaller than 100 nm) are able to actively penetrate directly into the bloodstream. With the development of toxicological knowledge about ultrafine particles (nanoparticles), attention to their potential risks to human health is falling.Understanding the relationship between the amounts of emissions, their physicochemical properties, and biological activity are very important when designing and implementing effective measures to reduce the risk of exposure to the population. The objective of the dissertation thesis is focused on determining the specific emissions (SE) TSP, PM10, PM2.5, PM1, PM0.1, from the combustion of solid fuels in small combustion equipment in normal operation in households - at nominal and reduced power, and during the combustion of different types of fuels. A suitable and practical usable method of taking individual particle size fractions to determine both the mass and number concentration of particles (PM0.1 - PM10) was developed. From the twenty five combustion tests performed, based on the percentage of PM10, ultrafine particles (UFP) represented an average of 8%wt., and PM1 fraction is represented by an average of 90%wt. When comparing numerical and mass concentrations of particles based on the percentage of the ultrafine particles in the PM1, they represented on average 65%num. amount and 10%wt. Absolute values of SE TSP and SE individual particle sizes are much higher among older types of combustion equipment. The newer types of combustion devices (automatic and gasification burners) reduce the SE of SCE very significantly. However, the value of the SE PM0.1 average remained the same. With regard to the results obtained, it is necessary to continue to concentrate on the characterization of SCE with a focus on fine and ultrafine particles. Identifying the physico-chemical properties of these particles to spread information about their level of toxicity and toxicological tests should be used, as some substances can be biologically highly active even when low concentrations of pollutants are present.