環保專案成果報告查詢系統

專案計畫編號	EPA-98-U1U4-04-001
經費年度	098
計畫經費	2,500 千元
專案開始日期	2009/04/02
專案結束日期	2010/01/31
專案主持人	高志明
主辦單位	永續發展室
承辦人	林燕柔
執行單位	國立中山大學產學營運中心
專案分類	土壤及地下水
中文關鍵字	乳化型釋氫基質, 整治牆, 現地生物復育
英文關鍵字	slow hydrogen-releasing material; biobarrier; contaminated groundwater; trichloroethylene;slow hydrogen-releasing material; biobarrier; contaminated groundwater; trichloroethylene
協同主持人
共同主持人	葉琮裕
計畫聯絡人	梁書豪
計畫聯絡電話	07-5252000#4419
計畫聯絡信箱	d953030004@student.nsysu.edu.tw

中文摘要	含氯有機溶劑普遍使用於脫脂、電子零件清洗及乾洗等工業製程中，為地下水中常見之重質非水相溶液(dense non-aqueous phase liquids, DNAPL)污染物，而三氯乙烯(trichloroethylene, TCE)則為國內外最具代表性之含氯有機溶劑。此外，三氯乙烯具有潛在之基因突變性及致癌性等毒性特徵，因此一旦發生三氯乙烯洩漏，將可能經由飲用水等多種暴露途徑，對鄰近民眾之健康造成嚴重危害。因此，本研究中將以三氯乙烯為目標污染物，研究發展處理DNAPL污染地下水之整治技術。常用之三氯乙烯整治技術包括抽取處理法、空氣注入法及化學藥劑處理法等，惟因污染之地下水為一動態環境，污染物濃度及環境因子隨整治時程之改變而不同，使得整治三氯乙烯污染地下水之困難度相當高，傳統整治技術無法因應此一動態環境，使整治效率及經費無法達到預期目標。由於三氯乙烯污染場址之整治是屬於長期性的工作，因此應用生物整治技術是較為經濟可行的整治方式。如此，將使整體之整治效益提高，並彌補傳統整治技術之缺點。惟三氯乙烯之生物降解需長期注入主要基質，但基質之注入將造成阻塞問題且易使注入井之操作及維護費用增加。因此，結合生物整治及透水性整治牆之概念，乃成為一種較為務實且突破傳統窠究之設計思維。如此，當可有效處理三氯乙烯污染之地下水，並可擴大應用於其他含氯有機溶劑污染場址之整治。本研究中以三氯乙烯為目標污染物，研究發展處理重質非水相溶液(dense non-aqueous phase liquids, DNAPL)污染地下水之整治技術。本研究之目的為設計生物透水性整治牆，並發展一種可緩慢釋放碳源、氫源及營養物質之基質，以加速三氯乙烯之生物降解。研究中所設計合成之基質將結合蔬菜油(慢速分解基質)、糖蜜(快速分解基質)及生物可分解界面活性劑(simple green, SG和卵磷脂)，使蔬菜油乳化為較易擴散之乳化型釋氫基質，以期長期提供微生物共代謝好氧或厭氧還原脫氯所需之碳源或氫源。本研究之工作項目包括乳化型釋氫基質合成、好氧及厭氧微生物批次試驗及管柱試驗。乳化油合成配方方面，以50%乳化油為基準，卵磷脂及SG濃度分別為72 mg/L及71 mg/L時，其乳化程度可達100%，顯示該配方為乳化最佳比例。乳化油合之成方式，以卵磷脂及SG混合乳化油以乳化均質機攪拌30分鐘所生成之粒徑最小，且界達電位為負值，有利於土壤孔隙間傳輸。乳化油之傳輸特性方面，乳化油及純蔬菜油會造成土壤孔隙的吸附阻塞而發生短流現象，但被吸附之油滴亦會進行脫附行為而進一步造成延遲現象的發生；但以上之延遲現象亦可能是因為土壤粒徑之異質性造成巨大粒徑分佈之乳化，於不同粒徑具有不同傳輸狀況下傳輸所造成蔬菜油/水對TCE之分配係數實驗顯示，蔬菜油對TCE有強的富集特性，可使高濃度三氯乙烯集中於蔬菜乳化油油滴中，當地下含水層環境尚未有厭氧產氫情況發生時，蔬菜油可有效攔阻溶於水中TCE，待微生物增長後，蔬菜油物理攔阻及微生物厭氧產氫脫氯反應同時發生，增強TCE之處理效率。卵磷脂、SG、糖蜜及釋氫基質皆可促進微生物進行TCE好氧共代謝，而綜合維他命雖可促進微生物生長，但無法有效刺激微生物作為TCE好氧共代謝之碳源。另外，糖蜜經微生物代謝後易產生有機酸，造成pH下降，進而造成微生物生長之抑制。卵磷脂、SG、綜合維他命、糖蜜、釋氫基質之降解比率依大小之分可得卵磷脂>糖蜜>SG>釋氫基質>綜合維他命>現地地下水(無基質)。此外，卵磷脂、SG及釋氫基質反應後之氧化還原電位(ORP)皆為還原態。而若環境緩衝能力充足，糖蜜亦可將ORP轉變為還原態。由微生物厭氧批次試驗得知，因此釋氫基質確實可有效促進厭氧生物還原脫氯反應，使TCE降解至乙烯。環境中硝酸鹽濃度過高時，可能會延緩釋氫基質產氫，進而延遲TCE還原脫氯作用。當反應環境處於富硫酸鹽狀態時，仍能持續產氫刺激脫氯菌進行還原脫氯作用。研究結果顯示，TCE之厭氧降解比率依序為釋氫基質組>富硫酸鹽組>富硝酸鹽組>現地地下水(無基質)。反應過程中之pH變化可能由於釋氫基質經厭氧發酵後所產生之有機酸導致，但由TCE之厭氧降解結果得知，pH變化應不會對微生物降解產生影響。由基因評估法得知，卵磷脂、SG、糖蜜及釋氫基質可測得phenol monooxygenase、toluene monooxygenase及toluene dioxygenase之基因，因此可有效針對微生物進行誘發酵素降解TCE的潛能。乳化型釋氫基質在單純釋氫基質及釋氫基質於富硝酸鹽和富硫酸鹽下皆可有效刺激Dehalococcoides菌群誘發生成tceA、bvcA及vcrA等還原脫氯酵素。由管柱試驗得知，以乳化型釋氫基質建立生物透水性整治牆同時具有下列機制：(1)蔬菜油對於TCE之富集性及(2)緩慢釋出氫氣及醋酸鹽促進厭氧還原脫氯作用產生等機制，因此可有效攔阻及降解TCE及其降解副產物，並透過溶氧消耗，使反應環境處於還原狀態下，更可促進厭氧脫氯菌群增長。若以管柱試驗之結果為例，TCE整治費用為9 NTD/mg TCE，由於僅以耗材成本預估，並無法實際估算人事、操作及維護成本。但若單純以整治面考量，厭氧處理仍是最經濟之方式，因此選用乳化型釋氫基質作為厭氧生物整治之基質可避免持續灌注之高操作費用，在考量成本及效能上，乳化型釋氫基質之生物透水性整治牆極具競爭力，但目前仍缺乏實際應用案例，未來將朝模場或實場應用，以加強該技術之應用性。
中文關鍵字	乳化型釋氫基質, 整治牆, 現地生物復育

中文摘要

含氯有機溶劑普遍使用於脫脂、電子零件清洗及乾洗等工業製程中，為地下水中常見之重質非水相溶液(dense non-aqueous phase liquids, DNAPL)污染物，而三氯乙烯(trichloroethylene, TCE)則為國內外最具代表性之含氯有機溶劑。此外，三氯乙烯具有潛在之基因突變性及致癌性等毒性特徵，因此一旦發生三氯乙烯洩漏，將可能經由飲用水等多種暴露途徑，對鄰近民眾之健康造成嚴重危害。因此，本研究中將以三氯乙烯為目標污染物，研究發展處理DNAPL污染地下水之整治技術。常用之三氯乙烯整治技術包括抽取處理法、空氣注入法及化學藥劑處理法等，惟因污染之地下水為一動態環境，污染物濃度及環境因子隨整治時程之改變而不同，使得整治三氯乙烯污染地下水之困難度相當高，傳統整治技術無法因應此一動態環境，使整治效率及經費無法達到預期目標。由於三氯乙烯污染場址之整治是屬於長期性的工作，因此應用生物整治技術是較為經濟可行的整治方式。如此，將使整體之整治效益提高，並彌補傳統整治技術之缺點。惟三氯乙烯之生物降解需長期注入主要基質，但基質之注入將造成阻塞問題且易使注入井之操作及維護費用增加。因此，結合生物整治及透水性整治牆之概念，乃成為一種較為務實且突破傳統窠究之設計思維。如此，當可有效處理三氯乙烯污染之地下水，並可擴大應用於其他含氯有機溶劑污染場址之整治。本研究中以三氯乙烯為目標污染物，研究發展處理重質非水相溶液(dense non-aqueous phase liquids, DNAPL)污染地下水之整治技術。本研究之目的為設計生物透水性整治牆，並發展一種可緩慢釋放碳源、氫源及營養物質之基質，以加速三氯乙烯之生物降解。研究中所設計合成之基質將結合蔬菜油(慢速分解基質)、糖蜜(快速分解基質)及生物可分解界面活性劑(simple green, SG和卵磷脂)，使蔬菜油乳化為較易擴散之乳化型釋氫基質，以期長期提供微生物共代謝好氧或厭氧還原脫氯所需之碳源或氫源。本研究之工作項目包括乳化型釋氫基質合成、好氧及厭氧微生物批次試驗及管柱試驗。乳化油合成配方方面，以50%乳化油為基準，卵磷脂及SG濃度分別為72 mg/L及71 mg/L時，其乳化程度可達100%，顯示該配方為乳化最佳比例。乳化油合之成方式，以卵磷脂及SG混合乳化油以乳化均質機攪拌30分鐘所生成之粒徑最小，且界達電位為負值，有利於土壤孔隙間傳輸。乳化油之傳輸特性方面，乳化油及純蔬菜油會造成土壤孔隙的吸附阻塞而發生短流現象，但被吸附之油滴亦會進行脫附行為而進一步造成延遲現象的發生；但以上之延遲現象亦可能是因為土壤粒徑之異質性造成巨大粒徑分佈之乳化，於不同粒徑具有不同傳輸狀況下傳輸所造成蔬菜油/水對TCE之分配係數實驗顯示，蔬菜油對TCE有強的富集特性，可使高濃度三氯乙烯集中於蔬菜乳化油油滴中，當地下含水層環境尚未有厭氧產氫情況發生時，蔬菜油可有效攔阻溶於水中TCE，待微生物增長後，蔬菜油物理攔阻及微生物厭氧產氫脫氯反應同時發生，增強TCE之處理效率。卵磷脂、SG、糖蜜及釋氫基質皆可促進微生物進行TCE好氧共代謝，而綜合維他命雖可促進微生物生長，但無法有效刺激微生物作為TCE好氧共代謝之碳源。另外，糖蜜經微生物代謝後易產生有機酸，造成pH下降，進而造成微生物生長之抑制。卵磷脂、SG、綜合維他命、糖蜜、釋氫基質之降解比率依大小之分可得卵磷脂>糖蜜>SG>釋氫基質>綜合維他命>現地地下水(無基質)。此外，卵磷脂、SG及釋氫基質反應後之氧化還原電位(ORP)皆為還原態。而若環境緩衝能力充足，糖蜜亦可將ORP轉變為還原態。由微生物厭氧批次試驗得知，因此釋氫基質確實可有效促進厭氧生物還原脫氯反應，使TCE降解至乙烯。環境中硝酸鹽濃度過高時，可能會延緩釋氫基質產氫，進而延遲TCE還原脫氯作用。當反應環境處於富硫酸鹽狀態時，仍能持續產氫刺激脫氯菌進行還原脫氯作用。研究結果顯示，TCE之厭氧降解比率依序為釋氫基質組>富硫酸鹽組>富硝酸鹽組>現地地下水(無基質)。反應過程中之pH變化可能由於釋氫基質經厭氧發酵後所產生之有機酸導致，但由TCE之厭氧降解結果得知，pH變化應不會對微生物降解產生影響。由基因評估法得知，卵磷脂、SG、糖蜜及釋氫基質可測得phenol monooxygenase、toluene monooxygenase及toluene dioxygenase之基因，因此可有效針對微生物進行誘發酵素降解TCE的潛能。乳化型釋氫基質在單純釋氫基質及釋氫基質於富硝酸鹽和富硫酸鹽下皆可有效刺激Dehalococcoides菌群誘發生成tceA、bvcA及vcrA等還原脫氯酵素。由管柱試驗得知，以乳化型釋氫基質建立生物透水性整治牆同時具有下列機制：(1)蔬菜油對於TCE之富集性及(2)緩慢釋出氫氣及醋酸鹽促進厭氧還原脫氯作用產生等機制，因此可有效攔阻及降解TCE及其降解副產物，並透過溶氧消耗，使反應環境處於還原狀態下，更可促進厭氧脫氯菌群增長。若以管柱試驗之結果為例，TCE整治費用為9 NTD/mg TCE，由於僅以耗材成本預估，並無法實際估算人事、操作及維護成本。但若單純以整治面考量，厭氧處理仍是最經濟之方式，因此選用乳化型釋氫基質作為厭氧生物整治之基質可避免持續灌注之高操作費用，在考量成本及效能上，乳化型釋氫基質之生物透水性整治牆極具競爭力，但目前仍缺乏實際應用案例，未來將朝模場或實場應用，以加強該技術之應用性。

中文關鍵字

乳化型釋氫基質, 整治牆, 現地生物復育

類型	檔名	檔案大小	說明	最新版公開日期
期末報告	final(公開).pdf	0MB		2010/6/1 上午 12:00:00

摘要	Soil and groundwater at many existing and former industrial areas and disposal sites is contaminated by halogenated organic compounds that were released into the environment. Halogenated organic compounds are heavier than water. When they are released into the subsurface, they tend to adsorb onto the soils and cause the appearance of DNAPL (dense-non-aqueous phase liquid) pool. Among those halogenated organic compounds, trichloroethylene (TCE), a human carcinogen, is one of the commonly observed contaminants in groundwater. Thus, TCE was used as the target compound in this study. One cost-effective approach for the remediation of the chlorinated-solvent and petroleum products contaminated aquifers is the installation of permeable reactive zones or barriers within aquifers. As contaminated groundwater moves through the emplaced reactive zones, the contaminants are removed, and uncontaminated groundwater emerges from the downgradient side of the reactive zones. The objective of this proposed study was to assess the potential of using a passive in situ carbon/hydrocarbon releasing barrier system to bioremediate TCE-contaminated groundwater. This passive active biobarrier system would have advantages over conventional systems including less maintenance, cost-effectiveness, no above-ground facilities, no groundwater pumping and reinjection, and groundwater remediation in situ. In this study, the unique biobarrier system has been developed. The biobarrier system included a carbon/hydrogen releasing barrier, which contained slow carbon/hydrogen-releasing materials. The slow carbon/hydrogen releasing material would cause the aerobic cometabolism and reductive dechlorination of TCE in aquifer. The carbon/hydrocarbon-releasing materials would release carbon when contacts with groundwater and release hydrogen after the anaerobic biodegradation of released carbon, thus cause the reductive dechlorination of TCE. In this study, batch experiments were operated to test the feasibility of using vegetable oil as the slow-released substrate, molasses as fast-degrading substrate, and biosurfactant [simple green (SG) and lecithin] to produce emulsified oil. Several experimental conditions included the concentrations of contaminants and substrates, shacking speed, and percentage of each component. In the batch experiment, emulsified oil was prepared by blending with water, vegetable oil, lecithin, and SG. The stable emulsified oil was formed after 30 min of blending. Results show that formed emulsified oil globule had the smallest diameter with negative zeta potential. The negative zeta potential of the oil droplets would increase the inter-particle repulsion between the droplets and soil particles, which was beneficial for the transportation of emulsified oil within the soil pores. However, the emulsified oil and the vegetable oil would also adsorb onto the soil particles (with positive zeta potential), and cause the following clogging of the soil pores. The sorbed oil droplets would desorb after the equilibrium was reached. The sorption mechanism and soil heterogeneity would also cause the retardation of oil in the soils. Compared with vegetable oil, results show that the emulsified oil caused more uniform sorption onto soil particles and lower oil to water partition coefficient. Moreover, results show that TCE had higher affinity to emulsified oil. Thus, emulsified oil droplets would help to retard TCE molecules before the anaerobic biodegradation of TCE can occur. Thus, the removal of TCE in water phase could be due to the mechanisms of sorption and biodegradation. Results from the microcosm study indicate that the addition of emulsified oil, cane molasses, SG, or lecithin would enhance the biodegradation rate of TCE under anaerobic conditions. However, addition of multivitamin would increase the bacterial population in the media but would not be able to enhance the TCE degradation rate. Results show that significant pH drop was observed due to the production of organic acids after the anaerobic biodegradation process of cane molasses. This also caused the inhibition of microbial growth in microcosms. Results reveal that higher TCE removal efficiency was observed in microcosms with lecithin addition followed by the addition of cane molasses, SG, emulsified oil, multivitamin, groundwater (without substrate addition). Moreover, reduced environmental conditions [with negative oxidation-reduction potential (ORP)] were observed after the addition of lecithin, cane molasses, SG, and emulsified oil. This would accelerate the reductive dechlorination of TCE in practical application. Results from the microcosm experiments also show that addition of cane molasses would significantly enhance the reductive dechlorination of TCE to the nontoxic end product (ethane). However, appearance of high nitrate concentration would inhibit the TCE degradation process due to the occurrence of denitrification. Compared with nitrate, high sulfate concentration would not have significant impact on the reductive dechlorination of TCE. Results from the gene analysis show that phenol monooxygenase, toluene monooxygenase, and toluene dioxygenase were observed in the microcosms with lecithin, cane molasses, SG, and emulsified oil. This indicates that the addition of substrates would induce the potential of TCE-degrading enzyme. Addition of emulsified oil and emulsified oil in nitrate or sulfate-rich media would stimulate Dehalococcoides sp. to induce tceA, bvcA, and vcrA, enzymes for TCE reductive dechlorination. Results from the column study indicate that two major TCE removal mechanisms caused by the emulsified oil are as follows: (1) adsorption of TCE onto oil globules, and (2) release of hydrogen and acetate to enhance the reductive dechlorination process. The slowly released substrates from the emulsified oil would also consume dissolved oxygen (DO) and produce reduced environmental conditions to enhance the growth of TCE-degraders. Results from the column study also indicate that the remediation cost is approximately NT$9 for each mg of TCE removal. However, the cost would go up if operation and maintenance cost is considered. Results of this study will aid in designing an in situ biobarrier system containing slowly released carbon/hydrogen materials for remedial application. The proposed treatment scheme would be expected to provide a more cost-effective alternative to remediate TCE and other chlorinated-solvent contaminated aquifers. Knowledge obtained from this study will aid in designing a carbon/hydrogen releasing reactive barrier system for site remediation.
英文關鍵字	slow hydrogen-releasing material; biobarrier; contaminated groundwater; trichloroethylene;slow hydrogen-releasing material; biobarrier; contaminated groundwater; trichloroethylene

摘要

Soil and groundwater at many existing and former industrial areas and disposal sites is contaminated by halogenated organic compounds that were released into the environment. Halogenated organic compounds are heavier than water. When they are released into the subsurface, they tend to adsorb onto the soils and cause the appearance of DNAPL (dense-non-aqueous phase liquid) pool. Among those halogenated organic compounds, trichloroethylene (TCE), a human carcinogen, is one of the commonly observed contaminants in groundwater. Thus, TCE was used as the target compound in this study. One cost-effective approach for the remediation of the chlorinated-solvent and petroleum products contaminated aquifers is the installation of permeable reactive zones or barriers within aquifers. As contaminated groundwater moves through the emplaced reactive zones, the contaminants are removed, and uncontaminated groundwater emerges from the downgradient side of the reactive zones. The objective of this proposed study was to assess the potential of using a passive in situ carbon/hydrocarbon releasing barrier system to bioremediate TCE-contaminated groundwater. This passive active biobarrier system would have advantages over conventional systems including less maintenance, cost-effectiveness, no above-ground facilities, no groundwater pumping and reinjection, and groundwater remediation in situ. In this study, the unique biobarrier system has been developed. The biobarrier system included a carbon/hydrogen releasing barrier, which contained slow carbon/hydrogen-releasing materials. The slow carbon/hydrogen releasing material would cause the aerobic cometabolism and reductive dechlorination of TCE in aquifer. The carbon/hydrocarbon-releasing materials would release carbon when contacts with groundwater and release hydrogen after the anaerobic biodegradation of released carbon, thus cause the reductive dechlorination of TCE. In this study, batch experiments were operated to test the feasibility of using vegetable oil as the slow-released substrate, molasses as fast-degrading substrate, and biosurfactant [simple green (SG) and lecithin] to produce emulsified oil. Several experimental conditions included the concentrations of contaminants and substrates, shacking speed, and percentage of each component. In the batch experiment, emulsified oil was prepared by blending with water, vegetable oil, lecithin, and SG. The stable emulsified oil was formed after 30 min of blending. Results show that formed emulsified oil globule had the smallest diameter with negative zeta potential. The negative zeta potential of the oil droplets would increase the inter-particle repulsion between the droplets and soil particles, which was beneficial for the transportation of emulsified oil within the soil pores. However, the emulsified oil and the vegetable oil would also adsorb onto the soil particles (with positive zeta potential), and cause the following clogging of the soil pores. The sorbed oil droplets would desorb after the equilibrium was reached. The sorption mechanism and soil heterogeneity would also cause the retardation of oil in the soils. Compared with vegetable oil, results show that the emulsified oil caused more uniform sorption onto soil particles and lower oil to water partition coefficient. Moreover, results show that TCE had higher affinity to emulsified oil. Thus, emulsified oil droplets would help to retard TCE molecules before the anaerobic biodegradation of TCE can occur. Thus, the removal of TCE in water phase could be due to the mechanisms of sorption and biodegradation. Results from the microcosm study indicate that the addition of emulsified oil, cane molasses, SG, or lecithin would enhance the biodegradation rate of TCE under anaerobic conditions. However, addition of multivitamin would increase the bacterial population in the media but would not be able to enhance the TCE degradation rate. Results show that significant pH drop was observed due to the production of organic acids after the anaerobic biodegradation process of cane molasses. This also caused the inhibition of microbial growth in microcosms. Results reveal that higher TCE removal efficiency was observed in microcosms with lecithin addition followed by the addition of cane molasses, SG, emulsified oil, multivitamin, groundwater (without substrate addition). Moreover, reduced environmental conditions [with negative oxidation-reduction potential (ORP)] were observed after the addition of lecithin, cane molasses, SG, and emulsified oil. This would accelerate the reductive dechlorination of TCE in practical application. Results from the microcosm experiments also show that addition of cane molasses would significantly enhance the reductive dechlorination of TCE to the nontoxic end product (ethane). However, appearance of high nitrate concentration would inhibit the TCE degradation process due to the occurrence of denitrification. Compared with nitrate, high sulfate concentration would not have significant impact on the reductive dechlorination of TCE. Results from the gene analysis show that phenol monooxygenase, toluene monooxygenase, and toluene dioxygenase were observed in the microcosms with lecithin, cane molasses, SG, and emulsified oil. This indicates that the addition of substrates would induce the potential of TCE-degrading enzyme. Addition of emulsified oil and emulsified oil in nitrate or sulfate-rich media would stimulate Dehalococcoides sp. to induce tceA, bvcA, and vcrA, enzymes for TCE reductive dechlorination. Results from the column study indicate that two major TCE removal mechanisms caused by the emulsified oil are as follows: (1) adsorption of TCE onto oil globules, and (2) release of hydrogen and acetate to enhance the reductive dechlorination process. The slowly released substrates from the emulsified oil would also consume dissolved oxygen (DO) and produce reduced environmental conditions to enhance the growth of TCE-degraders. Results from the column study also indicate that the remediation cost is approximately NT$9 for each mg of TCE removal. However, the cost would go up if operation and maintenance cost is considered. Results of this study will aid in designing an in situ biobarrier system containing slowly released carbon/hydrogen materials for remedial application. The proposed treatment scheme would be expected to provide a more cost-effective alternative to remediate TCE and other chlorinated-solvent contaminated aquifers. Knowledge obtained from this study will aid in designing a carbon/hydrogen releasing reactive barrier system for site remediation.

英文關鍵字

slow hydrogen-releasing material; biobarrier; contaminated groundwater; trichloroethylene;slow hydrogen-releasing material; biobarrier; contaminated groundwater; trichloroethylene