الفهرس 
Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
Greater Cairo suffers from a serious air quality problem resulting from the release of different air pollutants with high emission loads. Most of air pollutants have significant health impact on the human being, especially; particulate matter of diameter 10 micrometers or less (PM10), sulfur dioxide (SO2), and nitrogen dioxide (NO2).
Arab Abu Saed area is located approximately 40 km south to Cairo. This area contains more than 228 clay brick kilns which represent the largest cluster of brickworks in Egypt. All the brick factories are identically operated using the same old traditional Open-Hoffman kilns where fuel is combusted. The Heavy Fuel Oil (HFO) and the Natural Gas (NG) are the only available types of fuels to be used in these kilns.
The aim of this study is to assess the pollution reduction due to conversion of the fuel used from HFO to NG in 176 brick kilns using two Gaussian plume models (GPM), Classical GPM (CGPM) and American Environmental Regulatory Model (AERMOD). The assessment is focusing on three primary air pollutants; PM10, SO2, and NO2 in seven different locations surrounding the brick factories.
The fuel switching from HFO to NG has resulted in a significant emission load reduction of PM10, SO2, and NO2 that reached 96%, 72% and 24% respectively. This reduction has been resulted mainly due to the difference in the chemical composition between the HFO and NG and subsequently the combustion exhaust. The estimation of the pollutants’ concentrations using the two Gaussian dispersion models’ results show that Minya town has the highest concentration of PM10, SO2, and NO2 in case of burning HFO, while the lowest concentration is estimated to be at Tabbin South monitoring station if NG is used. However, Minya town is the most positively affected site of the pollution reduction resulting from the fuel switching.
Some statistical analyses were used to evaluate the correlation and the agreement of both Gaussian dispersion models’ results. Consequently, it is concluded that, in case of uncomplicated (flat) surrounding terrain and low wind speed condition, using Power law scheme to calculate the plume dispersion parameters in CGPM can give accurate results compared to the advanced Gaussian Plume models like AERMOD.
In addition, radiation activity measurements were carried out for six HFO samples to investigate the dispersion of occurring radionuclides in air resulting from burning the HFO and calculate the annual average effective dose to workers or public to assess the radiological hazard. The radiation measurement showed that, the average concentrations of Ra-226, Th-232 and K-40 per each kiln reached 7000, 6500, and 8000 Bq/day respectively. However, the average concentrations of naturally occurring radionuclides were considerable high; the average dose due to external exposure to different organs or tissues was 2.65 mSv/y. This value within the international permissible values for workers.
Furthermore, fifty samples of raw clay materials were collected from many factories in Arab Abu Saed area and were analyzed by HPGe detector to measure the total annual equivalent dose and effective dose due to exposure to average activity of all naturally occurring radionuclides (mSv/y) in clay bricks. Results show that radiological hazard due to external exposure for different organs or tissues for workers and public are within the international permissible values.