循環淋洗整治受疏水性有機化合物污染之土壤

Remediation for contaminated soil by HOC in soil washing circulation system

李家榮(Chia-Jung Lee)

指導教授 ： 泣奉華

崑山科技大學/工程學院/環境工程研究所/碩士(2007年)

摘要

隨著近年來工業快速的發展，有機化合物大量製造使用，破壞了大自然的平衡，亦對人類的生活環境造成極大的危害及威脅。而土壤污染在環境較不易被發掘，在整治上的困難度也較高。釵h研究已證實，受到疏水性有機化合物污染(hydrophobic organic compound, HOCs)之土壤可以利用界面活性劑(surfactant)增加HOCs之溶解性(Solubilization)，對土壤的整治(remediation)而言是一種有效之方式，但是淋洗液(desorption solvent)用量不可小歔，且淋洗液之後續收集處理不易，若能將淋洗液重複利用，不僅能降低淋洗液之用量，亦能降低整治成本。
本研究探討以淋洗方式整治受疏水性有機化合物污染之土壤，研究中所使用之PAHs為naphthalene及anthracene，將整治後之淋洗液經過活性碳吸附PAHs後，再回流至原來淋洗槽內，重複利用。
實驗結果顯示，所使用之淋洗液對土壤中PAHs能明顯的增加PAH的溶解度，且批次實驗證實，活性碳對於實驗用之界面活性劑之吸附效果較不明顯，但對PAHs卻有明顯之吸附(sorption)效果，因此大為增加循環系統之實用性。
連續流實驗亦證明，將淋洗通過污染土壤後之界面活性劑再次流過活性碳管柱，能將界面活性劑中溶解之PAHs吸附達99.9%以上，達到脫附液再生之幼纂C當再次更換污染土壤，以再生之界面活性劑進行脱附，雖然脱附之增溶高度有下降，但效果亦比CaCl2佳，初步估計為界面活性劑被吸附於活性碳上，使得微胞量降低，將已經活性碳將污染物吸附後，回流之界面活性劑添加回原來的濃度，實驗進行是利用界面活性劑由TOC測定下降之碳數，推算界面活性劑減少之濃度，以利於添加界面活性劑之量。實驗結果顯示，於第一天進行脱附時，其增溶高度約為20倍，第二天更換新土壤，並將界面活性劑條回原來的濃度進行實驗，其結果與未將界面活性劑之濃度進行調整比較，未將界面活性劑之濃度進行調整，其增溶高度約為13倍，而進行界面活性劑濃度調整後，發現其增溶高度與剛配置的界面活性劑差不多。

關鍵字

PAHs ； 土壤整治 ； 管柱實驗 ； 循環整治系統 ； HOCs

並列摘要

With the rapid industrial development recently and large amounts of usage in organic chemicals, the great nature balance has been badly damaged. This situation also causes extremely huge menace and damage to mankind. Furthermore, soil pollution cannot be found easily and it also results in higher difficulty for remediation. Many researches have testified that soils polluted with hydrophobic organic compound (HOCs) can be effectively remedied for soil by using surfactants to increase the solubilization of HOC. For soil remediation, it has proven to be an effective way. However, the volume consumed for desorption solvents should never be ignored and it is difficult for subsequent collection for desorption solvents. If the said desorption solvents can be reused, it cannot only reduce the volume consumed for desorption solvents, but also reduce the remediation cost.
This study is aimed to explore the soils polluted by HOC by means of washing circulation. The PAHs adopted in this study are naphthalene and anthracene. After the washing solvents after remediation are led through active carbon to make PAHs desorbed, solvents can be returned into original washing tanks for reusing. The study indicates the solvents used for this study can enhance the PAHs solubilization in soil. Also, batch experiments show that active carbon causes less significant sorption effect for surfactants used in this study but reversely cause significant sorption to PAHs. Thus, the operable application for this washing circulation system is well enhanced.
The continuous flow experiment also proves that when the surfactants washed and led through polluted soils are led through active carbon columns again, the PAH sorption solved by surfactants can reach 99.9% above and the renewal effect for sorption solvents can be effected accordingly. When the polluted soils are changed once more and desorbed with surfactants, despite reduced solubilization, the effect is still better than that of CaCl2. It is initially estimated that surfactants desorbed on active carbon will reduce micelle volume. If the volume desorbed by surfactants can be calculated and the surfactant condensation can be resumed, the micelle volume can be increased with better overall system available.
Flow experiment prove, through contaminated soil surfactant after in to flow through activated carbon in charge of the post to continue in succession, it can absorb anthracene dissolving in to surfactant, the desorption rate can be more than 99.9%, the renewable reason drenches the lotion. As changing the contaminated soil again, go on with the recycled surfactant. Person who enclose reduce to first take second place 65%, estimate reason that the surfactant is sorption on the activated carbon, make the little afterbirth amount reduce and reduce and take off the result of enclosing.

並列關鍵字

Column Experiments ； HOC ； Soil Remediation ； Washing Circulation System ； PAH

參考文獻

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