Summary: | 碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 101 === Erh-Jen River is located in southwestern Taiwan and is one of the most polluted rivers in Taiwan. Downstream of the river, untreated waste water from scrap metal waste incineration, pickling, and surface treatment has been discharged into the river for mor than three decades. This study collected sediment from Nan-Ding Bridge, downstream of the Erh-Jen River. Sediment was air-dried, passed through a 0.814 mm sieve then size-fractioned into five different particle sizes. The heavy metal analysis included total metal content, content extracted by 0.1 N HCl, and content extracted by 0.1 N NaOH. Heavy metal content was analyzed with Atomic Absorption spectrometry. The heavy metal results were as follows, Cu: 43.6-62.8 mg/kg, Cr: 37.3-41.7 mg/kg, Ni: 28.4-31.7 mg/kg, Cd: 0.08-0.35 mg/kg, Zn: 92.2-107.8 mg/kg, and Pb: 30.9-54.1 mg/kg. The order of total content for the heavy metals was Zn > Cu > Pb > Cr > Ni > Cd. The ranges of the enrichment factor (EF) for these metals were as follows: Cu 1.48 - 1.81, Cr 0.46 - 0.61, Ni 0.79 - 0.84, Cd 0.22 - 0.74, Zn 2.01 - 2.13, and Pb 1.11 - 1.29. The factors demonstrated that Cr, Ni, and Cd did not contaminate, Cu and Pb slightly contaminated, and Zn moderately contaminated the sediment. The enrichment factor implied that the major heavy metal polluters were Zn, Cu, and Pb in the Erh-Jen River.
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