THE EMISSION OF ULTRAFINE PARTICLES IN THE MANUFACTURE OF FIREPLACE CERAMIC TILES

摘要

Studies in the field of the adverse effect of inhaled particles show that not only particle mass is crucial but also particle size and specific surface are. The main objective of this study was to investigate and characterise ultrafine particle (UFP) emissions on workplace in the manufacture of ceramic tiles at two problematic places - at ceramic tiles kiln and spraying glazing suspension. The process of creating of glaze on the surface of stove tiles is performed at temperatures reaching up to 1,100℃. At this high temperature occurs fugitive emissions from glaze and ceramic consist of vapours and UFP containing various heavy metals such as Pb, Cr, Cu, Mo, Zr, etc. from glaze and ceramic, respectively. The data obtained from the measurements confirmed the significant emissions of UFP at the two chosen workplaces, but the composition of particles, their size distribution and other parameters differed from one to another. In case of the workplace near the kiln, the following parameters were noted: total concentration of particles ranging from 5.6 nm to 560 nm is 2×10~5-4×10~5 N/cm~3; median of size distribution is 37 nm, median of mass distribution is 153 nm, particle surface deposited in tracheobronchial (TB) part of lungs is 200 μm~2/cm~3, particle surface deposited in alveolar (A) part of lungs is 450 μm~2/cm~3 and the concentration of Pb is 3,744 μg/m~3. In the case of the manual spraying of the glaze suspension on tiles, the following parameters were noted: total concentration of particles is 2×10~5 N/cm~3; median of size distribution is 11 nm, median of mass distribution is 177 nm, particle surface deposited in TB part of lungs is 50 μm~2/cm~3, particle surface deposited in A part of lungs is 170 μm~2/cm~3 and the concentration of Pb is 1.9 μg/m~3. It can be concluded from the data above that both the measured workplaces meet the permissible exposure limit for lead, which is 50 μg/m~3. It is important to note that, in this study, the health impacts of UFP on staff and employees were not studied.