Ash Dust Concentration in the Vicinity of the Ash Disposal Site Depending on the Size of the Pond (Water Mirror)

Thermal power plants Nikola Tesla A and B are large sources of ash from their ashes/slag deposit sites Total sizes of ashes/slag depots are 600ha and 382ha, with active cassettes having dimensions similar to 200 ha and similar to 130 ha The active cassettes of the disposal sites are covered by rather large waste ponds the sizes of vary depending on the working condition of a sluice system and on meteorological conditions Modeling of ash lifting was attempted using results from the dust lifting research The relation between sizes of ponds and air dust concentration in the vicinity of ash disposal sites was analyzed As expected, greater sizes of dried disposal site surfaces in combination with stronger winds gave greater dust emission and greater air dust concentratio

Environmental Impact Assessment of the Nuclear Reactor in Vinca, Based on the Data on Emission of Radioactivity from the Literature - a Modeling Approach

Research activities of Vinca Institite have been based on two heavy water research reactors: a 10 MW one, RA, and zero power, RB. Reactor RA was operational from 1962 to 1982. In 2010, spent fuel has been sent to the country of origin, and the reactor now is in decommissioning. During the operational phase of the reactor there were no recorded accidental releases into the environment, only operational ones. Results of the environmental impact assessment of the assumed emission of radionuclides from the ventilation of nuclear reactor RA in Vinca to the atmospheric boundary layer are presented in this paper. Evaluation was done by using the Gaussian straight-line diffusion model and taking into account characteristics of the reactor ventilation system, the assumed emission release of radioactivity (from the literature), site-specific meteorological data for six-year period and local topography around nuclear reactor, and corresponding dose factors for inventory of radionuclides. Based on the described approach, and assuming that the range of appropriate meteorological data for six year period for the application of described mathematical model is enough for this kind of analysis, it can be concluded that the nuclear reactor RA, in the course of its work from 1962 to 1982, had no influence on the surrounding environment through the air above regulatory limits

Representativity of Air Quality Control in Limited Number of Grid Points

In this study, we point to loss of accuracy in representing a field of air pollution concentration due to reduction of number of monitoring points or changes in their location. Using a Gaussian-type diffusion model, a high resolution concentration field was generated from 17 points representing the actual distribution of possible pollution sources. The starting grid consisted of 90 601 points. Then we reduced number of points by two orders of magnitude, forming the grid of 961 points. After that, the second reduction to 36 points was performed, still forming a regular grid. Finally, we had 16 points whose positions are in a qualitative agreement with the actual distribution of sampling stations in the area

Modeling air concentration of fly ash in Belgrade, emitted from thermal power plants TNTA and TNTB

The aim of the study was to estimate if dust/fly ash emitted into the atmosphere from chimneys and the ash disposal sites of the thermal power plants Nikola Tesla A and B in Obrenovac could increase the concentration of PM10 in New Belgrade. TNTA and TNTB are close to Belgrade (population of 2.5 million) and it is important to estimate the amount of the pollution emitted into the atmosphere from these sources. The pollution from chimneys is estimated from yearly amounts of discharge, while the lifting of ash/coal dust was parameterized by the model. The used model is the straight-line Gaussian plume model written in the Fortran programming language. The first estimation was done using mathematical modeling for the idealized situation with prescribed winds and stability. The second estimation was done using the observed meteorological data for the whole year of 2009. With strong winds (over 40 km/h), dust will reach Belgrade in dozens of minutes, while during moderate winds (similar to 10-30 km/h), it would take about one hour to reach it. In these cases atmosphere is close to the neutral stability class. In case of weaker winds and stable atmosphere, the increase of air dust concentration in Belgrade would start after a few hours (6-10). Regarding the other two sources of pollution, coal handling piles and ash deposit sites, during strong winds ( GT 40 km/h) and neutral stability, fly ash would reach Belgrade in several dozen of minutes. (C) 2016 Published by Elsevier B.V. on behalf of Institution of Chemical Engineers

Representativity of Air Quality Control in Limited Number of Grid Points

In this study, we point to loss of accuracy in representing a field of air pollution concentration due to reduction of number of monitoring points or changes in their location. Using a Gaussian-type diffusion model, a high resolution concentration field was generated from 17 points representing the actual distribution of possible pollution sources. The starting grid consisted of 90 601 points. Then we reduced number of points by two orders of magnitude, forming the grid of 961 points. After that, the second reduction to 36 points was performed, still forming a regular grid. Finally, we had 16 points whose positions are in a qualitative agreement with the actual distribution of sampling stations in the area