Please use this identifier to cite or link to this item:
標題: 加氯量對自來水不鏽鋼管線生物膜消長影響之研究
The effect of different chlorine levels in controlling bioflm formation on stainless steel surfaces in distribution systems
作者: 蔡長憲
Tasi, Chang-Hsien
關鍵字: biofilm;生物膜;drinking water;distribution system;自來水;配水管線
出版社: 環境工程學系
本研究的目的即在探討不同加氯濃度對自來水不鏽鋼管線生物膜生長的影響。研究中採用異營菌平板計數、ATP biomass、濾膜法測大腸菌以及菌種的分離及觀察等方法,同時配合模式模擬,評估加氯對於管線生物膜消長的影響,作為未來自來水廠控制微生物污染的參考依據。
由試驗結果顯示,在異營菌計數方面,不加氯的情況下,培養14週後生物膜密度可達最大值8.7×105 CFU/cm2,且隨著培養時間增長,生物膜會愈趨於穩定。在加氯的試程中,高加氯濃度對生物膜累積的速率比低濃度慢,但隨著培養時間的增加會愈接近。在ATP biomass方面,不加氯情況下平均生物膜形成速率(biofilm formation rate, BFR)為325.2 ATP pg/cm2day,低加氯濃度與高濃度試程則分別為159及118.4 ATP pg /cm2day。在大腸菌方面,加氯對大腸菌的抑制作用僅開始培養時有效,而不同加氯濃度在抑制大腸菌效果上,並無明顯差異。另外,在菌種分離方面,生物膜中分離出的菌種種類較原水中多,且以革藍氏陰性桿菌居多。

Generally speaking , most the effluents of the water treatment plant can fill drinking water prescripts now . But it is frequent that consumers complain the quality of drinking water . According to the references , this phenomenon results from the recontamination of transport processes . And biological contamination is regarded as the primary problem , furthermore the problem of biofilm accumulation is especially tough and difficult to be treated .
The purpose of this research is to study the effect of different chlorine levels in controlling bioflm formation on stainless steel surfaces in distribution systems . For evaluating the effect of chlorination , including heterotrophic plate counts , ATP biomass analysis , coliform measurement with membrance method and separation and observation of biofilm bacteria was applied to the experiment , then a water quality model was used to simulate the result all together . Furthermore the results can apply to the operation of the water treatment industries .
The results of experiments indicated that maximum heterotrophic plate counts levels of the biofilm was 8.7×105 CFU/cm2 after 14 weeks of exposure for non-chlorine water and the biofilm became steadier with cultivated time extending . The accumulation rate of biolilm for high-chlorine level water was lower than low-chlorine level water , but the contrast diminished with cultivated time extending . Average biofilm formation rates was 325.2 ATP pg/cm2day for non-chlorine water , 159 and 118.4 ATP pg /cm2day for low-chlorine and high-chlorine level water . Chlorination showed a bit of effects in controlling attached coliform in cultivated incipiency , and there are no difference between chlorine levels . The bacterial species separated from biofilm were more than from original water , and most of these species were Gram-negative bacteria .
The theoretical results showed that the propose model could predict the experimental data well . The accumulative rate of attached bacteria in the distribution system increased with the decrease of the chlorine level and the enhance of the concentration of free bacteria , DOC , and BDOC . From a sensitivity analysis , The concentration of attached bacteria was higher under the conditions of higher utilized rate of substrates , lower natural decayed rate , higher resistive ability to chlorine , and took more time to grow into stabilized condition .
Appears in Collections:環境工程學系所

Show full item record

Google ScholarTM


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.