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年度	106	專案性質	實驗性質
專案類別	研究專案	研究主題	評估
申請機構	國立高雄師範大學	申請系所	生物科技系(所)
專案主持人	陳士賢	職等/職稱	教授
專案中文名稱	整治場址及離場處理場污染土壤總石油碳氫化合物快速篩檢方法效能評估
中文關鍵字	總石油碳氫化合物,快速篩檢方法,整治場址,離場處理場
專案英文名稱	Evaluating Efficacy of Soil Screening Methods of Total Petroleum Hydrocarbon in Contaminated soils in Remediated Sites and Ex-situ Treatment facility
英文關鍵字	Total petroleum hydrocsrbons,Soil screening methods,Remediated sites,Off site treatment facility
執行金額	1,050,000元
執行期間	2017/1/9 至 2017/11/30
計畫中文摘要	如何在發現油品污染初期，判斷洩漏來源並加以截斷，並減少實驗室分析成本，大幅縮短調查工作的時間，乃是非常關鍵的議題，本研究目的為提升總石油碳氫化合物(total petroleum hydrocarbon, TPH)現場篩測儀器之功能性，並了解其可能分析方法限制性，以強化現場篩測方法與傳統TPH分析結果之相容性。 工作項目主要分為兩個部分:實驗室測試及污染場址測試，實驗室測試首先針對一系列自行配置柴油污染土壤以RemScan進行污染土壤TPH分析，其TPH濃度範圍介於1060至52800 mg/kg，此一系列柴油污染土壤對應RemScan分析測值之相關係數為R2=0.9696，顯示不同濃度梯度之柴油污染土壤與RemScan TPH測值具高相關性。並將此一系列柴油污染土壤其檢測結果以GC/MS進行TPH分析，其TPH濃度介於770至59066 mg/kg，此一系列柴油污染土壤對應GC/MS TPH分析之相關係數為R2=0.9930，顯示不同濃度梯度之柴油污染土壤與TPH測值具極高相關性。在比對此一系列柴油污染土壤濃度測值時，可以發現在污染土壤TPH濃度小於10000 mg/kg時，RemScan數值較傳統TPH分析方法為高，但在污染土壤TPH濃度大於10000 mg/kg時，RemScan數值則較傳統TPH分析方法為低。 為探討不同污染土壤其污染時間長短對偵測之影響，因此以RemScan檢測新近石化污染土壤及受長期風化作用之石化污染土壤，測試不同污染年代的石化污染土壤，及評估TPH濃度高低對RemScan檢測之影響，並比較與傳統分析方法數據之差異性。在本研究中RemScan測值與GC/MS分析測值準確度以相對誤差來表示，在檢測8個樣品中有6個樣品得其測值，其兩種方法相對誤差介於3.37-20.4%。 污染場址測試選擇不同油品污染之場址，進行RemScan現場測試工作，並比較與傳統TPH分析方法數據之差異性，了解儀器偵測濃度線性範圍。針對污染場址中污染土壤樣品源自不同油品(如汽油加柴油、柴油加潤滑油)，挑選三個石化污染場址土壤樣品進行試驗，發現二處石化污染場址RemScan之測值均高於GC/MS分析。針對土壤樣品前處理發現土壤樣品以60C烘乾及自然風乾前處理所得之RemScan測值較接近，但自然風乾前處理需時72小時之等待時間，可能不符合現場及即時性之需求，因此若含水率過高之樣品將建議使用40C或60C烘乾，但經烘乾或風乾後碳數範圍屬於前端之化合物則會溢散，故此儀器不適合分析含有汽油之樣品。 在污染場址測試並於南部某台塑加油站污染場址進行18個污染土壤樣品RemScan測定，部分樣品無測值，6個樣品之RemScan之TPHd所測讀值均高於GC/MS測值，RemScan之測值與GC/MS分析檢測數據的相對誤差屬可接受範圍，5個樣品之RemScan之TPHd所測讀值低於GC/MS測值。在南部某中油加油站污染場址進行18個污染土壤樣品測定，多數樣品無測值，發現3個樣品RemScan之TPHd測值高於GC/MS測值。 土壤樣品中存在RemScan無法分析之樣品，評估應為土壤質地影響RemScan無法進行檢測，發現可分析之土壤樣本主要分佈於砂土（sand）、壤質砂土（loamy sand）、砂質壤土（sandy loam）及壤土（loam）；不可分析之土壤樣本則主要分佈於黏土（clay）、坋質黏土（silty clay）、坋質黏壤土（silty clay loam）、黏質壤土（clay loam）、砂質黏壤土（sandy clay loam）。於實驗同時亦發現土壤有機碳之含量會對RemScan檢測造成影響，有機碳含量從3.15% - 6.28%影響TPH測值數值為220.0 – 4140 mg/kg。 根據原廠之檢驗證明得知，RemScan之最低偵測極限為250 mg/kg，實際針對不同土壤可能有所變異。RemScan分析檢測數據僅需不到30秒即可得其測值，每小時可收集超過30筆之數據，可進行持續性操作。操作不需使用任何耗材，僅需維持電池電量供RemScan檢測分析。RemScan檢測僅使用紅外光照射樣品表面，樣品表面反射吸收之紅外光進入儀器偵檢器後獲得讀值，分析過程並無添加任何藥劑，故並無以化學性或物理性破壞樣品，檢測後樣品並可用於傳統TPH分析萃取使用。限制性為RemScan使用需避免含水率過高之因素，於含水率大於8%無法檢測，含水率低於8%亦能檢測，故樣品需風乾亦或是烘乾。因其紅外光射出區域僅直徑1 cm，測試需充分拌勻，並且需要夯實使其表面平坦，建議檢測時需進行5重複，以確保儀器檢測之可信度及準確性。根據原廠聲明，RemScan可檢測所有土壤質地之土樣，但須選擇不同土壤質地（砂土、黏土及坋土）之土壤為標準土進行校準，及建立其污染土壤檢量線方可使用，故欲分析之土壤需先判斷其土壤質地後方能進行模式選擇，爾後進行污染土壤測定。本研究發現適用於砂土及壤土，其適用之土壤質地尚需更多實際操作以累積數據。
計畫英文摘要	Total petroleum hydrocarbons (TPH) is a term used to describe a large family of several hundred chemical compounds that originally come from crude oil. The typical range from C6–C40 consist of fractions and classes. The fractions range from gasoline, through kerosene, diesel, jet fuel and crude oil. TPH analyses are required by regulatory agencies to evaluate subsurface contamination. These analyses are needed to assess the subsurface contamination stemming from leaking underground fuel tanks, spills, and product delivery lines. Evaluating the extent of contamination by TPH requires the following considerations in the field: type of hydrocarbon contamination, age of the hydrocarbon, type of matrix (water, soil, sludge), and distribution of hydrocarbon. Limitations of the TPH analytical method chosen from an environmental perspective not only total petroleum measurement is a requirement, but the compound classes and sometimes the individual components need reporting. This is due to the toxicity differences between the classes and individual compounds. In addition it is also very useful to know what fraction of petroleum is present, in the case of site investigation, under remediation processes or site closure. The objective of this project is to evaluate individual field measurement devices in laboratory and field studies. Quantitative results of TPH instrument (i.e., RemScan developed by Ziltek) were generated from laboratory and contaminated sites to draw conclusions regarding technology performance. In details, the tasks of laboratory measurement and field test were to: (1) determine the method detection limit, (2) evaluate the accuracy and precision of TPH measurement for a variety of contaminated soil samples, (3) evaluate the effect of interferents on TPH measurement, (4) evaluate the effect of soil moisture content on TPH measurement, (5) measure the time required for TPH measurement, and (6) estimate costs associated with TPH measurement. A series of diesel contaminated soils were prepared to verify correlation of TPH concentration gradient versus response of RemScan analysis in the laboratory. The TPH ranged from 1060 to 52800 mg/kg by RemScan analysis. Correlation was considered acceptable. Conventional TPH analysis was also performed by gas chromatograph/mass spectrometer (GC/MS). Concentrations of TPH ranged from 770 to 59066 mg/kg. When soil contains TPH less than 16000 mg/kg, it was observed that values of RemScan was normally higher than GC/MS analysis. However, when soils with TPH content higher than 16000 mg/kg, RemScan illustrated compatible results with GC/MS analysis. It was proposed that concentration of TPH at 10000 mg/kg may be the cutting point for better results. Weathered diesel contaminated soils were analyzed by both methods. Relative error ranged between 3.37 to 20.4% in 6 samples. Weathering effect of diesel contaminated soil did not affect the detection of TPH by field measurement device. However, 2 soil samples with texture of loamy sand cannot be detected by RemScan. Apparently physical characteristics of soil may affect application of RemScan in field work. Due to the limitation of instrument allowing sample with water content less than 8%, methods of sample pretreatment were assessed. The results indicated that oven dry at 40 or 60C is proper prior to RemScan analysis. Environmental samples were collected from three contaminated sites with mixture of diesel, gasoline, or lubricating oil. Among three samples tested in contaminated sites, RemScan demonstrated higher TPH values than conventional TPH method. Twenty four samples were collected from two gas stations which were operated by Formosa Petrochemical Corporation and CPC Corporation, respectively. Four samples from Formosa Petrochemical Corporation owned gas station indicated higher value by RemScan analysis. Also two samples from CPC Corporation owned gas station indicated higher value by RemScan analysis. Overall RemScan is a hand-held portable instrument that can be operated stand alone without the need for electricity or computer equipment. It is suitable for a full 8-hour day of infield use with only one battery swap. Also RemScan is easy to use and can be operated by relatively unskilled personnel in the field (i.e. <2 hours of training). No extra certification is required. It takes less than 30 seconds to collect a measurement from an air-dried sample with RemScan. For air-dried soil samples (<5% free moisture content by weight), the total sample measurement time, including preparation of a flat surface, is less than 2 minutes. Under this scenario, the instrument can collect more than 30 TPH measurements per hour. Operation does not require any consumables or hazardous chemicals. Calibrating the instrument takes less than 3 minutes after every hour of continuous use. The RemScan method is non-destructive in the sense that the measured soil can be left in, or returned to, its original location without significantly altering its physical and chemical properties. Certainly variety of soil texture and soil moisture are the limitation to its function. However, it offered compatible result of TPH analysis.