To investigate the an air pollution by particulate matter and its dispersion, a cement plant produceing portland cement 600, 000 ton/year and its vicinity were ´´,surveyed from Obtober, 1980 to April, 1983.
The survey was main?y focusde on main stack emmission rate of the cement plant and particle size distrioetijon in the dust, dustfall and total suspended particulate concentration in the area by month and distance from the stack.
The results of the study were as foil=aws;
1. The main stack emission rate was surveyed before and after the spray tower was additionally installed to the original E.P and bag filter. Before the spray tower installed, the main stack emission rate was higher (0.648/Nm3) than the emission standard of Korean Environmental Preservation Law´s (0.5g/Nm3, amended to 0.4"m3 on April 1983), but after the spray tower was installed, its main stack emission rate was markedly decreased to the standard (0.438/Nm3).
2. 23pm of the particle size was the Iargest portion (20.8%) of the dust particulate from the main stack and 50% of the frequency distribution was 1. 5pm Of the size. Most particle size was below l0pm.
3. The spray tower reduced the dustfall to 37.819.76 ton/km´-/month while dustfall appeared at 45.2915.45 ton/km2/month, in the vicinity of plant before spray tower installed
4. Mean concentrations of total suspended particulate for 24 hours; of the various stations were determined in 20.6200. Oug/m3, 3 stations of tham were higher than the value of Harry and William´s arthmetic average standard 130pg/m3.
5. Linear regression between dustfall(X) and total suspended particulate(Y) concentration was an equation, Y=4. 024X+11. 479. (r=0. 913
6. During the whole seasons in the opposite area 100m apart from the emission source the prevailing wind direction was with estimated more than 30ton/km2/month, and the concentration of total suspended particulate for 24 hrurs averaging time was more than 140ug/ m3 in the same area and direction.
7. Assumi la the wind direction were constant through the day ~iustfalIs for a day were
estimated at 13. 40ton/km2Jday, 10.79ton/l;m=/day and 4.55ton/km~II/day at various distances of 100m, 500nn and 1,500m from the emission source respectively.
8. In the simutaliou of dustfall and suspended dust by area., Gaussian dispersion model mod-
ified by size distribution of particulate matter was not appEcated since the emission of dust were from multi sources other them stack.
From the above results, it could be applied that the dispersion of dust from the cement plant is estinated and regulated for the purpose of environmental protection.
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