淨水場回收廢水中重金屬風險評估之研究

The study for risk assessment of heavy metals in recycling wastewater from water treatment plant

林文嵐(Wen-Lan Lin)

指導教授 ： 張添晉

國立臺北科技大學/工程學院/環境規劃與管理研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00094

摘要

為因應台灣水資源短缺及水資源再利用之國際環保趨勢，回收廢水再利用更顯其必要性；台灣自來水公司迴用淨水場程序廢水早已行之有年，將廢水行廢水處理程序處理而獲得較潔淨之上澄液，此上澄液採取全量或少量之回收方式迴用並與原水混合，再經後續淨水程序處理後供人民飲用，然而廢水迴用後，可能因淨水處理程序所添加化學藥劑，造成水質中重金屬重複累積而提高後人民續飲用風險。
本研究選取6座(依處理量分大型及中小型)具有代表性之淨水場，針對各場枯、豐水期之回收廢水水質進行實際採樣，並將採樣數據整合分析，以評估回收廢水迴用對人體造成之健康風險。本研究採用美國環保署國家研究委員會（NAS-NRC）建議之風險評估四大步驟、美國環保署綜合風險資訊系統(IRIS)發佈之致癌及非致癌參數以及國民飲用水生活習慣和體態等因素，針對回收廢水中7項重金屬物質進行人體健康風險評估；回收廢水中7項重金屬經致癌及非致癌風險量化評估，結果顯示，除麥寮第二淨水場枯水期之風險值略高於10-6外，其餘5座淨水場枯豐水期癌症風險(Risk)低於10-6及非致癌危害指數(HI)小於1，回收廢水迴用所造成致癌及非致癌風險之影響低，因此無論淨水場之類型為大型亦或中小型，回收廢水於枯豐水期階段仍可全量回收再利用。
此外，本研究亦以風險評估之架構，設定致癌及非致癌目標風險值，以提出淨水場回收廢水風險管理執行步驟之建議，以及淨水場回收廢水存有風險危害之因應策略，進而達成國內淨水場回收廢水管理之目標。

關鍵字

回收廢水 ； 風險評估 ； 風險資訊分析 ； 風險管理

並列摘要

Due to lack of water resource in Taiwan as well as trend of global resource utilization, wastewater recycle and reuse is truly important. For Taiwan water corporation, recycling wastewater out of water purification process has been implemented for several years. It lets wastewater treat by treatment process and obtains cleaner supernatant liquid, the cleaner the supernatant liquid with the whole volume or a small amount of recovery mode reuses back to Water Separation Well and mixes with raw water, and then treated by water treatment process. However, the pollutants of recycling wastewater were cumulative, which resulted in the risk of drinking water quality This study selected seven heavy mentals including dissolve aluminum, lead, chromium, cadmium, mercury, selenium and arsenic to be the subject matter of risk assessment.
This study selected 6 representative water treatment plants, focusing on their wastewater qualities analysis in different seasons, and integrated sampling data to access human health risks caused by the recovery of wastewater. This study utilized the four steps of risk assessment which proposed by U.S. Environmental Protection Agency National Research Council, the parameters of carcinogenic and non carcinogenic which emitted by U.S. Environmental Protection Agency Integrated Risk Information System, and took drinking habits and body into account to assess seven heavy metals in recycling wastewater on human health risk. Except the carcinogenic risk of Mailiao Water Treatment Plant with recycling wastewater during dry season was higher than 10-6 ,other water treatment plants in different seasons caused carcinogenic and non-carcinogenic risk were qualified with two standard indicators such as cancer risk was less than 10-6 and non-carcinogenic hazard index was smaller than 1. The effect of causing carcinogenic and non-carcinogenic risk in recycling wastewater was very low; therefore, whether water treatment plant was large or small scale, recycling wastewater in different seasons could be total amount recycled.
Furthermore, this study also utilized risk assessment framework and set risk targets including cancer and non-carcinogenic risk values to draft the risk management operational recommendations in recycling wastewater and also provided proper solutions to recycling wastewater in water treatment plant which had harmful risk.

並列關鍵字

recycling wastewater ； risk assessment ； information analysis of risk ； risk management

參考文獻

【21】 謝俊明，「利用HPLC-ICP/MS 進行尿中砷物種生物偵測」，勞工安全衛生研究季刊，第14卷，第3期，2006年，第195-204 頁。

【51】 行政院衛生署，台灣一般民眾暴露參數會編，2008。

【52】 行政院衛生署(2007年)．民國95年衛生統計系列（六）衛生統計動向。

【2】 National Research Council (NRC). 1983. Risk assessment in the federal government: managing the process. NAS Press, Washington DC.

【5】 行政院勞工委員會勞工安全衛生研究所，勞工作業場所化學危害暴露之風險評估-先驅計劃，2004年。