Studies of behavior of atmospheric mercury concentration at genera land mercury deposits areas
1983 Volume 18 Issue 1 Pages 66-76
Details
1983 Volume 18 Issue 1 Pages 66-76
Atmospheric mercury was measured by continuous monitor of Nippon Instruments Co. Ltd. Mercury AM-1 model used the collection by gold amalgamization method and the analysis by cold flamelesss atomic absorption spectroscopy.
The distribution of atmospheric mercury was investigated at four locations (commercial, background, mercury deposits and mercury deposits' neighbourhood areas) in Nara Prefecture, which have different environments. The two former were measured for 30 minute period and the two latter were measured for 1 hour period.
The amount of atmospheric mercury collected at the commercial area ranged from 1.89 to 16.40ng/m3, and the mean value and standard deviation was 5.12±2.12 ng/m3 (n=92). On the other hand, at the background area ranged from 1.87 to 3.87ng/m3, and the mean value and standard deviation was 2.54±0.50ng/m3 (n=45).
The hourly deviation of atmospheric mercury concentration at background area was so little compared to the commercial area.
The behavior of atmospheric mercury concentration at commercial area showed similar to CO, NO2, NOx and SO2 concentration, and moreover, the correction between atmospheric mercury and them showed strong correlation (r=0.606-0.742, n=80: CO, n=92: NO2, NOx, SO2). From this, atmospheric mercury was estimated to generate combustion systems. All fossil fuels contain 0.002-2 ppm mercury themselves, and almost of them are used to combustion energy. The mercury in fossil was estimated to emit to atmosphere together with NO2, NOx, SO2 and CO.
As to meteorological conditions, atmospheric mercury was not correlated with them. As there was no stationary generated origins as destruction plant and large factory near the sampling point of commercial area, no characteristic tendency was not shown to wind direction.
The behavior oaf tmospheric mercury concentration in basin as Nara showed high in night and low in day. This is estimated to the stability of air in a similar manner as concentration of NO2 and other air pollutants emitted in burning systems. From this, it is evident that atmospheric mercury is estimated to emit from the combustion system.
The mean value and standard deviation of atmospheric mercury concentration at mercury deposits area was 142.82±93.87 ng/m3 (n=136), and the maximum value was over 350ng/m3 and even minimum value was over 30ng/m3. On the other hand, these value at mercury deposits' neighbourhood area apart 650 m from mercury deposits area was 13.29±9.46ng/m3, and the maximum value was 47ng/m3 and the minimum value was 3.87 ng/m3.
