Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/5580
標題: 水井厭氧腐蝕模擬管柱之菌相研究―螢光原位雜交技術結合化學分析
作者: 林正晏
關鍵字: fluorescence in situ hybridzation;螢光原位雜交;sulfate reducing bacteria;oxygen release compound;sulfide;硫酸鹽還原細菌;釋氧物質;硫化物
出版社: 環境工程學系
摘要: 
在水井腐蝕問題上,以硫酸鹽還原細菌(Sulfate Reducing Bacteria,SRB)產生的硫化氫腐蝕最為嚴重。本研究著重於探討添加抑制劑後對SRB的影響,藉由螢光原位雜交(Fluorescence in situ Hybridzation,FISH)進行SRB、古細菌以及硫氧化菌的菌數分析,以瞭解不同種類抑制劑以及抑制劑量對微生物族群結構之變化,以及對SRB與硫化氫所造成的影響為何。
在井水分析中,由傳統SRB計數培養方法與FISH均證實受腐蝕的井水中存在著SRB,顯示SRB的存在可能造成井水腐蝕。但在傳統培養上,培養基對微生物的選擇性、微生物的活性以及培養技術誤差……等因素,常造成分析上環境中微生物的族群結構上造成偏差與低估。由井水樣品的採樣分析中,在安慶三的地區中,地下水中SRB及T. Thiooxodans與T. Ferrooxidans所佔的比例較表層水高,表示該地區的SRB在地下水中較具優勢,當SRB增加時,T. Thiooxodans與T. Ferrooxidans 的比例也隨之增加,可能SRB所產生的還原硫可當作硫氧化細菌的電子接受者,並促成水井內部的硫循環。
為瞭解造成水井產生硫化氫腐蝕問題,因此在管柱培養中,於SRB產生硫化氫後,添加各類型抑制劑來控制水中的硫化氫。實驗時分析pH、溶氧、ORP、TOC、溶解性硫化物、硫酸鹽…等水質參數的變化以及藉由螢光原位雜交法瞭解水中細菌結構之變化。在管柱培養初期,由FISH與硫化氫的分析顯示,當探針SRB385的雜交訊號開始產生的同時,水中硫化氫的濃度便突然增加,證實SRB385探針能有效的顯示出SRB族群變化。
添加抑制劑的管柱培養中,過氧化鎂與釋氧物質(oxygen release compound,ORC®TM)的添加並沒有立即對硫化物產生抑制反應,需等到SRB385的雜交訊號消失後才有明顯的成效,顯示過氧化鎂與ORC對SRB並沒有立即的抑制成效,但添加過氧化鎂與ORC會影響硫酸鹽還原速率(Sulfate Reduction Rate,SRR),無添加抑制劑時SRR為7.68 mg‧L-1‧day-1(R2為0.8958);添加10克過氧化鎂則SRR降為2.15 mg‧L-1‧day-1(R2為0.7177);當再添加10 克ORC後, SRR為-0.1238 mg‧L-1‧day-1 (R2為0.0175),顯見添加ORC較過氧化鎂能有效的降低硫酸鹽還原作用之發生。在管柱培養過程中,溶氧一直維持在極低的濃度下,顯示過氧化鎂與ORC釋出的溶氧會立即被消耗,但水中的硫化氫仍長期維持在高濃度的狀態下,這結果顯示當水中有足夠的硫酸根供SRB利用時,硫化氫被抑制劑氧化的速率並不會遠大於SRB產生硫化氫的速率,直到水中硫酸根濃度很低時,硫化氫的濃度才有明顯的減少。
當硫化物濃度高時,添加10 ml氯化鐵(aq)會明顯造成硫化物濃度的下降,添加鐵鹽之結果會造成硫化鐵的沈澱現象,但是溶解性硫化物的莫耳數減少量為1.044 mmol;添加250 ppm氯化鐵溶液10 ml,所造成的莫耳數變化為9.26 μmol,兩者相差甚大。因此無論是沈澱或者是氧化還原反應均無法有效解釋硫化物濃度大量減少的原因,最可能的原因便是添加鐵鹽會促進利用微生物利用硫化物的活性。
同時添加1 ml過氧化氫以及10 ml氯化鐵溶液的效應,會造成六號管柱的溶解性硫化氫濃度在第五十四天到第七十五天間均低於 10 mg/L。但SRB的細菌比例卻由第五十四天的9.29%緩慢的上升到第七十天的45.70%,顯示添加低劑量過氧化氫以及鐵鹽的效應,會對SRB造成立即性的抑制作用,同時鐵鹽的添加用於促進利用硫化物的微生物生長。由FISH分析的資料也指出,過氧化氫對SRB有很強的抑制作用,但缺乏持效性,當水中溶氧低於0.5 mg/L後,溶氧則不足以抑制SRB生長,造成SRB在管柱培養環境中仍有機會成為優勢族群。

Sulfate reducing bacteria(SRB) produces hydrogen sulfide which is most critical problem in corroded-well .This research discuss as the addition of inhibitors how to influence SRB activity variation for reducing corrosion . bacterium structure transform analysis eubacteria、archaea、SRB and sulfur-oxidizing bacteria by fluorescence in situ hybridzation (FISH) . utilizing FISH to understand in different inhibitor species and different inhibitor dosage how to influence SRB activity and hydrogen sulfide production .
In well sample analysis, this experimental result confirm that SRB existence in well by traditional microbiological culturing techniques and FISH, revealing SRB action maybe cause corroded-well problem, but traditional microbiological culturing techniques easy to cause bacterium structure analysis bias for medium selectiveness、bacteria activity diversity、experimentation aberration in environment sample . In sample of Anqing-3 , SRB385 and THIO820 hybridzation signal percentage in ground water is higher than surface water ,Which reveal SRB transmission pass way maybe from groundwater to supply . When SRB385 hybridzation signal percentage increase THIO820 hybridzation signal percentage increase together , because SRB produce hydrogen sulfide which supply electron donor for T. Thiooxodans and T. Ferrooxidans .
In column culturing experiment add different inhibitor species in media . The experimentation purpose is to understand inhibitor how control hydrogen sulfide to produce . The experimentation analysis pH、DO、ORP、total organic carbon、dissolved sulfide and sulfate to understand chemical parameter variation ﹔The experimentation is to understand bacteria structure transform by FISH techniques . The initial stage of experiment , dissolved sulfide concentration increase when SRB385 hybridzation signal percentage produce .This result to prove SRB385 probe can represent SRB group .
In additive-inhibitor of column culturing experiment , addition magnesium peroxide or oxygen release compound (ORC) do not have immediately effect for hydrogen sulfide produce control . The sulfide concentration obvious decrease until SRB385 hybridzation signal disappear . The result to prove magnesium peroxide or ORC do not have immediately effect for SRB activity control . But addition magnesium or ORC can influence Sulfate Reduction Rate(SRR) . In non-additive- inhibitor of column culturing experiment , the SRR is 7.68 mg‧L-1‧day-1 (R2 is 0.8958)﹔In additive-magnesium peroxide of column culturing experiment , the SRR is 2.15 mg‧L-1‧day-1(R2 is 0.7177)﹔In additive-magnesium peroxide and ORC of column culturing experiment .After addition magnesium peroxide and ORC , the SRR is -0.1238 mg‧L-1‧day-1 (R2 is 0.0175) . The result to prove addition magnesium peroxide or ORC can reduce sulfate reduction . In column culturing experiment process , DO keep low concentration all along , the result to reveal magnesium peroxide or ORC release oxygen which is consummated in a moment . If media had enough sulfate to provide SRB to utilize , the hydrogen sulfide keep high concentration in long-term. The result reflect inhibitor to oxidize sulfate rate is not obviously high than sulfide produce rate .
When sulfide keep high concentration , addition 10 ml of iron(Ⅲ) chloride can seriously change sulfide concentration and produce iron sulfide precipitation . addition iron(Ⅲ) chloride mole number is 9.26 μmol , but decreased sulfide concentration is 1.044 mmol , the result can not explain by chemical reaction cause sulfide concentration seriously change , probably addition iron can provide some bacteria usefully oxidation sulfide .
When addition 1 ml hydrogen peroxide and 10 ml of iron(Ⅲ) chloride together , the effect mark sulfide concentration rapidly disappear and sulfide maintain low concentration for next twenty five days . Addition inhibitor and iron cause SRB385 hybridzation signal percentage decrease from 52.42 % to 9.29 % . After that SRB385 hybridzation signal percentage moderately increase . The result reflect sulfide effective control by addition 1 ml hydrogen peroxide and 10 ml of iron(Ⅲ) chloride together . result indicate that addition 1 ml hydrogen peroxide and 10 ml of iron(Ⅲ) chloride together can decrease SRB activity or increase sulfide oxidation efficiency . This experiment prove that hydrogen peroxide can rapidly exterminate SRB group. But SRB maybe revive when dissolved oxygen concentration is smaller than 0.5 mg/L .
URI: http://hdl.handle.net/11455/5580
Appears in Collections:環境工程學系所

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