| Summary: | 碩士 === 國立成功大學 === 環境工程學系碩博士班 === 92 === The air pollution due to the volatile organic compounds (VOCs) and the odorous problems in the petrochemical park were concerned by its neighborhood. The characterization of the odorous components, chosen from the consideration of the reference papers, the raw material list of the factories in the Da-She petrochemical industry park and the thresholds value of odorous compounds, was conducted in this study.
Twice of continuous 48 hours air sampling with the interval of two hours per time using the Canister followed the Method To-14, in the populated and sensitive sites of S1 upwind and S2 downwind around the Da-She industry park, was conducted in this study to measure 11 components (using GC/PFPD for hydrogen sulfide, GC/MS for VOCs and ammonium analyzer) including benzene, toluene, ethylbenzene, xylene, styrene, arcrylonitrile, 1,3-butidiene, MMA, ammonium and hydrogen sulfide, and the resolution of the investigation results accompanying with the variation of time and wind direction and velocity.
The major odorous components measured in the S1 site, located at the upwind of the industry park but downwind of the Jern-Shen freeway, included benzene (B), toluene (T), ethylbenzene (E), and m,p-xylene (X). Both of the average ratio of BTEX of 1:2.8:0.8:0.9 in the S1 site being 1.2 ~ 1.7 time of 1:3.4:0.6:0.5 in the site S2 were close to the ratio of 1:2.4:0.5:1.9 from the vehicle emission, which showed that the S1 and S2 sites were apparently effected by the freeway emission. However, in the S2 site the concentration range of the petrochemical components ammonium, acrylonitrile, 1,3-butidiene, styrene and MMA releasing from the factory were 2.2 ~111 ppb, 0.3 ~ 42.6 ppb, 0.4 ~ 14.9 ppb, 1.5 ~ 6.2 ppb and 0.5 ~ 0.6 ppb respectively that corresponded to the ratio of 75.3:10.7:7.1:5.3:1, which being larger than that of 14.6:1.2:1.2:6.6:1 in site S2 showed that the effect due to the petrochemical factories emission was significant in site S2.
The components of ammonium and hydrogen sulfide, measured in site S1 always existing in the same time and not belong to the vehicle emission, indicated that the further investigation of its potential source was needed. On the other aspect, these compounds including acrylonitrile, 1,3-butidiene, styrene and MMA measured in the S2 site appearing at the same duration of a.m. 11:00 ~ p.m.7:00 indicated that was caused from the emission of the factories in the industry park., while the similar occasion of the ammonium and toluene observed simultaneously was correlated to the emission from two factories . The major wind source of the S2 in the daytime (a.m. 6:00 ~ p.m. 6:00) being the western direction, and the western north and eastern south direction in the nighttime (p.m. 6:00 ~ a.m. 6:00) came from the industry park, which resulted in the 1.1 ~ 12.4 time of industry contents in the daytime larger than that in the nighttime.
The odor strength, defined as the ratio of measured concentration to the thresholds concentration, of the ammonium and toluene appearing often with higher concentration were the major odorous components in the petrochemical park, while some components come from industrial emission was measured seldom with lower concentration and odor strength in the order of styrene, MMA, 1,3-butidiene and acrylonitrile. The square of the correlation coefficient between the total concentration and the total odor strength of all odorous components measured twice in the S2 sits of 0.8 and 0.7 were significant for the identification of the odorous components.
The comparisons of measuring the VOCs between the continuous monitoring system in site and the method TO-14 sampling by canister obtained the square of the correlation coefficient of 0.62 ~ 0.96, owing to the lower instant concentration existing in the VOCs monitoring system in site and the higher concentration obtaining in the canister sampling method spending more time.
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