TFT-LCD (Thin-film transistor liquid crystal display)為台灣近年重點發展之工業之一，而隨著其產量的增加，大量的廢水也同時產生，預計TFT-LCD工業之總廢水量會高達200,000 CMD，而其中33%為有機廢水，主要之成分包括二甲基亞楓(Dimethylsulfoxide, DMSO)、乙醇胺(Monoethanolamine, MEA)以及氫氧化四甲基銨(Tetramethylammonium hydroxide, TMAH)，而這些物質在生物處理上會有一定的困難，因其不容易被微生物利用。
本研究建立二連序批式反應器(Sequencing Batch Reactor, SBR)以探討TFT-LCD有機廢水之生物可降解性，以及其降解效率。此二SBR分別以無氧/好氧(Anoxic/Oxic, A/O)以及好氧(aerobic)之方式操作，其進流基質為人工配置之TFT-LCD有機廢水，主要含有DMSO、MEA及TMAH，經過長期監測發現，DMSO、MEA及TMAH之去除率均達99%以上，此顯示生物處理此種廢水之可行性，而MEA及TMAH降解中產生之氨氮則會經硝化作用轉化為硝酸鹽氮。
即便這三個成分在反應槽操作下有極高的去除率，為了確認光電廢水生物處理俱有環境友善性，針對其代謝中間產物進行批次實驗，發現在厭氧情形下，DMS是主要的DMSO中間代謝產物，無法順利降解至硫酸根。進一步針對DMSO在不同情形下進行降解觀察，同樣在厭氧態，DMS仍為主要的DMSO中間代謝產物，而在好氧情形則可以完全氧化成硫酸根。由於以往在廢水處理系統中往往只提到DMS所導致臭味問題，鮮少針對DMS對於廢水處理效率的影響。在批次實驗中發現，DMS會抑制硝化反應，在DMS被分解後，硝化現象才得以開始。可見DMSO分解成DMS後，是否可以降解至硫酸根將是影響廢水處理廠操作的重要關鍵。
利用16S rDNA 定序反應槽汙泥,發現Hyphomicrobium and Thiobacillus 是主要可以把DMSO氧化成硫酸根的菌群。螢光雜合技術(FISH)結果也同樣印證Hyhpomicrobium是主要的DMSO分解的族群。利用T-RFLP技術，可以發現在好氧反應槽具有較高比例的Hyphomicrobium菌群，在Thiobacillus 和Hyhpomicrobium則同時出現在AO反應槽，在降解DMS的批次實驗中，Hyphomicrobium的活性伴隨著硫酸根的生成上升了五倍。另外使用T-RFLP在偵測氨氧化細菌的部分，發現在好氧反應槽的主要族群是Nitrosospira 和Nitrosomonas europaea, 而在AO反應槽中則是Nitrosomonas europaea 和TF491。在批次實驗中，發現TF491這一群氨氧化菌會被DMS抑制，但對Nitrosomonas europaea抑制性較不顯著，可見Nitrosomonas europaea是在光電廢水處理中主要的氨氧化細菌，而DMS可能導致氨氧化細菌多樣性降低。
本研究也探討一實廠TFT-LCD AO MBR廢水處理廠之效能，該廠的汙染物包含MEA, TMAH和DMSO。經長期監測結果發現該廠之TMAH及MEA去除率達99%；DMSO的去除率也高達99%，但實際轉化成硫酸根的約只有77%，而約23%以DMS的形式逸散的空氣中。
本研究發現，無中間代謝產物的TFT-LCD廢水生物處理在好氧情形下是可行的。但若需合併脫氮程序需要進一步之研究以找到最佳之處理程序。

Thin-film transistor liquid crystal display (TFT-LCD) is one of the most promising industries in Taiwan in the 21st century. Along with the increasing production of TFT-LCD, more and more wastewater from the manufacturing processes is also produced. The total amount of TFT-LCD wastewater in Taiwan is expected to be as high as 200,000 CMD in the future. Nearly one third of the TFT-LCD wastewater is organic, mainly comprises of dimethylsulfoxide (DMSO), monoethanolamine (MEA), and tetramethylammonium hydroxide (TMAH). These compounds were considered to be slow- or non-biodigradable.
In this study, two lab-scale sequencing batch reactors (SBRs) were established to study the biodegradability of TFT-LCD wastewater. These two SBRs were operated as anoxic/oxic and aerobic respectively, with synthetic TFT-LCD wastewater (containing DMSO, MEA, and TMAH) as substrate. From the long-term monitoring, the removal efficiency of DMSO, MEA, and TMAH was as high as 99%. This implies that biodegradation of this kind of wastewater is feasible. Because MEA and TMAH are organic nitrogen compounds, ammonia was produced during their biodegradation and further be nitrified to nitrate.
Though with high removal efficiency, the intermediates produced during biodegradation of TFT-LCD were still unknown. Therefore, the mechanism of the degradation of DMSO, MEA, and TMAH under different conditions was also studied. No specific intermediate besides ammonia was detected during MEA and TMAH degradation. However, for DMSO, large amount of odorous dimthylsulfide (DMS) was produced under anaerobic condition. DMS was also found out to be an inhibitor of nitrification in this study. This implies that the presence of DMS is a major problem of TFT-LCD wastewater treatment.
From the results of 16S rDNA cloning sequencing, Hyphomicrobium and Thiobacillus were the dominant DMSO-degrading communities in our systems. This result was also verified by fluorescence in-situ hybridization (FISH). Terminal restriction fragment length polymorphism (T-RFLP) was also used to study the community of the two SBRs. In aerobic SBR, Hyphomicrobium was found to be the dominant community and both Hyphomicrobium and Thiobacillus were found in A/O SBR. We also used the T-RFLP method to study the communities of ammonia oxidizing bacteria (AOB) in our system. The main AOB communities in aerobic SBR were Nitrosospira sp. and Nitrosomonas europaea. For A/O SBR, Nitrosomonas europaea and TF491 were the dominant communities. In the batch tests, we observed that TF491 was suppressed with the presence of DMS. This might make the communities of AOB less diverse in TFT-LCD wastewater treatment processes.
A full-scale anoxic/oxic membrane bioreactor (A/O MBR) treating TFT-LCD wastewater was also investigated in this study. From the long-term monitoring results, more than 99% of DMSO, MEA, and TMAH were removed in this process. However, the conversion rate of DMSO to sulfate was only 77%, about 23% was emitted to the atmosphere as organic sulfur compounds, like DMS. Therefore, reducing the production of such kind of volatile sulfur compounds is crucial for TFT-LCD wastewater treatment.
In summary of this study, aerobic treatment without production of intermediates was feasible. But further studies are needed to obtain the optimum process for treating carbon, nitrogen, and sulfur simultaneously.

Ahn, J., T. Daidou, et al. (2001). "Metabolic behavior of denitrifying phosphate-accumulating organisms under nitrate and nitrite electron acceptor conditions." Journal of Bioscience and Bioengineering 92(5): 442-446.
Alef, K. and D. Kleiner (1989). "Rapid and sensitive determination of microbial activity in soils and in soil aggregates by dimethylsulfoxide reduction." Biology and Fertility of Soils 8(4): 349-355.
Amann, R. and B. M. Fuchs (2008). "Single-cell identification in microbial communities by improved fluorescence in situ hybridization techniques." Nat Rev Micro 6(5): 339-348.
Amann, R., W. Ludwig, et al. (1995). "Phylogenetic identification and in situ detection of individual microbial cells without cultivation." Microbiol. Rev. 59(1): 143-169.
Andreae, M. (1980). "Dimethylsulfoxide in marine and freshwaters." Limnology and Oceanography 25(6): 1054-1063.
Anthony, C. (1982). The biochemistry of methylotrophs, Academic Pr.
Arellano-Garcia, L., S. Revah, et al. (2009). "Dimethyl sulfide degradation using immobilized Thiobacillus thioparus in a biotrickling filter." Environ Technol 30(12): 1273-1279.
Balows, A. (1992). The Prokaryotes: a handbook on the biology of bacteria: ecophysiology, isolation, identification, applications, Springer-Verlag.
Beller, H. R., P. S. Chain, et al. (2006). "The genome sequence of the obligately chemolithoautotrophic, facultatively anaerobic bacterium Thiobacillus denitrificans." J Bacteriol 188(4): 1473-1488.
Bentley, R. and T. G. Chasteen (2004). "Environmental VOSCs--formation and degradation of dimethyl sulfide, methanethiol and related materials." Chemosphere 55(3): 291-317.
Bremner, J. M. and L. G. Bundy (1974). "Inhibition of nitrification in soils by volatile sulfur compounds." Soil Biology and Biochemistry 6(3): 161-165.
Briones, A. M., S. Okabe, et al. (2002). "Influence of Different Cultivars on Populations of Ammonia-Oxidizing Bacteria in the Root Environment of Rice." Appl. Environ. Microbiol. 68(6): 3067-3075.
Charlson, R., J. Lovelock, et al. (1987). "Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate." Month: 655-661.
Chen, T. K., C. H. Ni, et al. (2003). "Nitrification–Denitrification of Opto-electronic Industrial Wastewater by Anoxic/Aerobic Process." Journal of Environmental Science and Health, Part A: Toxic/Hazardous Substances and Environmental Engineering 38(10): 2157 - 2167.
Cheng, X., E. Peterkin, et al. (2005). "A study on volatile organic sulfide causes of odors at Philadelphia's Northeast Water Pollution Control Plant." Water Research 39(16): 3781-3790.
Cho, K.-S., M. Hirai, et al. (1991). "Degradation characteristics of hydrogen sulfide, methanethiol, dimethyl sulfide and dimethyl disulfide by Thiobacillus thioparus DW44 isolated from peat biofilter." Journal of Fermentation and Bioengineering 71(6): 384-389.
Cho, K. S., M. Hirai, et al. (1992). "Degradation of hydrogen sulfide by Xanthomonas sp. strain DY44 isolated from peat." Appl Environ Microbiol 58(4): 1183-1189.
Claus, G. and H. Kutzner (1985). "Physiology and kinetics of autotrophic denitrification by Thiobacillus denitrificans." Applied Microbiology and Biotechnology 22(4): 283-288.
Cotter, P. A. and R. P. Gunsalus (1989). "Oxygen, nitrate, and molybdenum regulation of dmsABC gene expression in Escherichia coli." Journal of Bacteriology 171(7): 3817-3823.
DE Beer, D., J. C. VAN DEN Heuvel, et al. (1993). "Microelectrode Measurements of the Activity Distribution in Nitrifying Bacterial Aggregates." Appl. Environ. Microbiol. 59(2): 573-579.
De Bont, J. A. M., J. P. Van Dijken, et al. (1981). "Dimethyl Sulphoxide and Dimethyl Sulphide as a Carbon, Sulphur and Energy Source for Growth of Hyphomicrobium S." J Gen Microbiol 127(2): 315-323.
De Zwart, J. M. M. a. K., J.G. (1992). "C1-cycle of sulfur compounds." Biodegradation 3(37-59).
De Long, E., G. Wickham, et al. (1989). "Phylogenetic stains: ribosomal RNA-based probes for the identification of single cells." Science 243(4896): 1360.
Edwards, K., W. Bach, et al. (2004). "Neutrophilic iron-oxidizing bacteria in the ocean: their habitats, diversity, and roles in mineral deposition, rock alteration, and biomass production in the deep-sea." Geomicrobiology Journal 21(6): 393-404.
Gilomen, S. (2007). Identifying ammonia and nitrite oxidizing bacteria responsible for nitrification in opto-electronic wastewater, SOUTHERN ILLINOIS UNIVERSITY AT CARBONDALE.
Glindemann, D., J. Novak, et al. (2006). "Dimethyl sulfoxide (DMSO) waste residues and municipal waste water odor by dimethyl sulfide (DMS): the north-east WPCP plant of Philadelphia." Environ. Sci. Technol 40(1): 202-207.
Glindemann, D., J. Novak, et al. (2006). "Dimethyl Sulfoxide (DMSO) Waste Residues and Municipal Waste Water Odor by Dimethyl Sulfide (DMS): the North-East WPCP Plant of Philadelphia." Environmental Science and Technology 40: 202-207.
Grady, C., G. Daigger, et al. (1999). Biological wastewater treatment, Marcel Dekker Inc.
Griebler, C. (1997). "Dimethylsulfoxide (DMSO) reduction: a new approach to determine microbial activity in freshwater sediments." Journal of Microbiological Methods 29(1): 31-40.
Hayes, A. C., Y. Zhang, et al. (2009). "Linking performance to microbiology in biofilters treating dimethyl sulphide in the presence and absence of methanol." Appl Microbiol Biotechnol.
Hirano, K., J. Okamura, et al. (2001). "An efficient treatment technique for TMAH wastewater by catalyticoxidation." IEEE transactions on semiconductor manufacturing 14(3): 202-206.
Huang, S. (2006). "Bioprocess study and ecological dynamics of non-woven membrane bioreactor treating TFT-LCD wastewater."
Jensen, A. B. and C. Webb (1995). "Treatment of H2S-containing gases: A review of microbiological alternatives." Enzyme and Microbial Technology 17(1): 2-10.
Jewell, T., S. L. Huston, et al. (2008). "Methylotrophy in freshwater Beggiatoa alba strains." Appl. Environ. Microbiol.: AEM.00379-00308.
Juliette, L. Y., M. R. Hyman, et al. (1993). "Inhibition of Ammonia Oxidation in Nitrosomonas europaea by Sulfur Compounds: Thioethers Are Oxidized to Sulfoxides by Ammonia Monooxygenase." Appl. Environ. Microbiol. 59(11): 3718-3727.
Kane, S. R., A. Y. Chakicherla, et al. (2007). "Whole-Genome Analysis of the Methyl tert-Butyl Ether-Degrading Beta-Proteobacterium Methylibium petroleiphilum PM1." Journal of Bacteriology 189(5): 1931-1945.
Kiene, R. P., R. S. Oremland, et al. (1986). "Metabolism of Reduced Methylated Sulfur Compounds in Anaerobic Sediments and by a Pure Culture of an Estuarine Methanogen." Appl. Environ. Microbiol. 52(5): 1037-1045.
Knapp, J., N. Jenkey, et al. (1989). "The anaerobic biodegradation of diethanolamine by a nitrate reducing bacterium." Biodegradation 7(3): 183-189.
Koito, T., M. Tekawa, et al. (1998). "A novel treatment technique for DMSO wastewater." IEEE transactions on semiconductor manufacturing 11(1): 3-8.
Kuske, C., S. Barns, et al. (1997). "Diverse uncultivated bacterial groups from soils of the arid southwestern United States that are present in many geographic regions." Applied and Environmental Microbiology 63(9): 3614.
Labbe, N., V. Laurin, et al. (2007). "Microbiological community structure of the biofilm of a methanol-fed, marine denitrification system, and identification of the methanol-utilizing microorganisms." Microbial Ecology 53(4): 621-630.
Lai, B. and W. K. Shieh (1996). "Batch monoethylamine degradation via nitrate respiration." Water Research 30(10): 2530-2534.
Large, P., D. Peel, et al. (1961). "Microbial growth on C1 compounds. 2. Synthesis of cell constituents by methanol-and formate-grown Pseudomonas AM1, and methanol-grown Hyphomicrobium vulgare." Biochemical Journal 81(3): 470.
Layton, A. C., P. N. Karanth, et al. (2000). "Quantification of Hyphomicrobium populations in activated sludge from an industrial wastewater treatment system as determined by 16S rRNA analysis (vol 66, pg 1167, 2000)." Applied and Environmental Microbiology 66(11): 5106-+.
Lee, D., M. Lee, et al. (2004). Strain for decomposing TMAH, and method of wastewater treatment using the same, Google Patents.
Lee, Y., C. Lee, et al. (2004). "Kinetics and mechanisms of DMSO (dimethylsulfoxide) degradation by UV/H2O2 process." Water Research 38(10): 2579-2588.
Lei, C. N. (2008). "Study of the degradation mechanism of TFT-LCD organic wastewater under aerobic, anoxic and anaerobic conditions (Master thesis)." National Cheng Kung University, Taiwan.
Lim, J., S. Baek, et al. (2009). "Ferruginibacter alkalilentus gen. nov., sp. nov. and Ferruginibacter lapsinanis sp. nov., novel members of the family'Chitinophagaceae'in the phylum Bacteroidetes, isolated from freshwater sediment." International journal of systematic and evolutionary microbiology 59(10): 2394.
Lin, H. L. (2006). "Study on reaction kinetics characteristics of Thin-film Transistor Liquid Crystal Display Wastewater by SBR reactor." National Cheng Kung University.
Lin, I. S. (2006). "利用分子生物技術分析光電業廢水生物處理單元菌相結構之研究(Master thesis)." 國立中央大學.
Liu, W., T. Marsh, et al. (1997). "Characterization of microbial diversity by determining terminal restriction fragment length polymorphisms of genes encoding 16S rRNA." Appl. Environ. Microbiol. 63(11): 4516-4522.
Lomans, B. P., C. van der Drift, et al. (2002). "Microbial cycling of volatile organic sulfur compounds." Cellular and Molecular Life Sciences 59(4): 575-588.
Lukow, T., P. Dunfield, et al. (2006). "Use of the T-RFLP technique to assess spatial and temporal changes in the bacterial community structure within an agricultural soil planted with transgenic and non-transgenic potato plants." FEMS Microbiology Ecology 32(3): 241-247.
McTavish, H., J. A. Fuchs, et al. (1993). "Sequence of the gene coding for ammonia monooxygenase in Nitrosomonas europaea." Journal of Bacteriology 175(8): 2436-2444.
MEIBERG, J. B. M., P. M. BRUINENBERG, et al. (1980). "Effect of Dissolved Oxygen Tension on the Metabolism of Methylated Amines in Hyphomicrobium X in the Absence and Presence of Nitrate: Evidence for Aerobic Denitrification." J Gen Microbiol 120(2): 453-463.
MEIBERG, J. B. M. and W. Harder (1978). "Aerobic and Anaerobic Metabolism of Trimethylamine, Dimethylamine and Methylamine in Hyphomicrobium X." J Gen Microbiol 106(2): 265-276.
Mobarry, B. K., M. Wagner, et al. (1997). "Phylogenetic probes for analyzing abundance and spatial organization of nitrifying bacteria (vol 62, pg 2157, 1996)." Applied and Environmental Microbiology 63(2): 815-815.
Mohan, S., N. Rao, et al. (2005). "Treatment of complex chemical wastewater in a sequencing batch reactor (SBR) with an aerobic suspended growth configuration." Process Biochemistry 40(5): 1501-1508.
Mrklas, O., A. Chu, et al. (2003). "Determination of ethanolamine, ethylene glycol and triethylene glycol by ion chromatography for laboratory and field biodegradation studies." Journal of Environmental Monitoring 5(2): 336-340.
Murakami-Nitta, T., K. Kirimura, et al. (2003). "Degradation of dimethyl sulfoxide by the immobilized cells of Hyphomicrobium denitrificans WU-K217." Biochemical Engineering Journal 15(3): 199-204.
Murakami-Nitta, T., H. Kurimura, et al. (2002). "Continuous degradation of dimethyl sulfoxide to sulfate ion by Hyphomicrobium denitrificans WU-K217." J Biosci Bioeng 94(1): 52-56.
Nakatsu, C. H., K. Hristova, et al. (2006). "Methylibium petroleiphilum gen. nov., sp. nov., a novel methyl tert-butyl ether-degrading methylotroph of the Betaproteobacteria." Int J Syst Evol Microbiol 56(5): 983-989.
Ndegwa, A., R. Wong, et al. (2004). "Degradation of monoethanolamine in soil." Journal of Environmental Engineering and Science 3(2): 137-145.
Olsen, G., D. Lane, et al. (1986). "Microbial ecology and evolution: a ribosomal RNA approach." Annual Reviews in Microbiology 40(1): 337-365.
Park, H. (2005). Effect of dissolved oxygen on ammonia-oxidizing bacterial communities in activated sludge, THE UNIVERSITY OF WISCONSIN-MADISON.
Park, H. and D. Noguera (2004). "Evaluating the effect of dissolved oxygen on ammonia-oxidizing bacterial communities in activated sludge." Water Research 38(14-15): 3275-3286.
Park, S., Y. K. Ku, et al. (2006). "The characterization of bacterial community structure in the rhizosphere of watermelon (Citrullus vulgaris SCHARD.) using culture-based approaches and terminal fragment length polymorphism (T-RFLP)." Applied Soil Ecology 33(1): 79-86.
Park, S., T. Yoon, et al. (2001). "Biological treatment of wastewater containing dimethyl sulphoxide from the semi-conductor industry." Process Biochemistry 36(6): 579-589.
Regan, J., G. Harrington, et al. (2002). "Ammonia-and nitrite-oxidizing bacterial communities in a pilot-scale chloraminated drinking water distribution system." Applied and Environmental Microbiology 68(1): 73.
Sanger, F., S. Nicklen, et al. (1977). "DNA sequencing with chain-terminating inhibitors." Proceedings of the National Academy of Sciences 74(12): 5463.
Suylen, G. and J. Kuenen (1986). "Chemostat enrichment and isolation of Hyphomicrobium EG." Antonie Van Leeuwenhoek 52(4): 281-293.
Toyoda, A., T. Koito, et al. (1998). "Efficient treatment technique for DMSO wastewater." NEC RES DEV 39(2): 101-105.
Urakami, T., H. Araki, et al. (1990). "Isolation and identification of tetramethylammonium-biodegrading bacteria." Journal of Fermentation and Bioengineering 70(1): 41-44.
USEPA (1999). "Wastewater technology fact sheet sequencing batch reactors." EPA 832-F-99-073.
Wang, A. J., D. Z. Du, et al. (2005). "An innovative process of simultaneous desulfurization and denitrification by Thiobacillus denitrificans." J Environ Sci Health A Tox Hazard Subst Environ Eng 40(10): 1939-1949.
Ward, N. L., J. F. Challacombe, et al. (2009). "Three Genomes from the Phylum Acidobacteria Provide Insight into the Lifestyles of These Microorganisms in Soils." Appl. Environ. Microbiol. 75(7): 2046-2056.
Weon, H., B. Kim, et al. (2006). "Niastella koreensis gen. nov., sp. nov. and Niastella yeongjuensis sp. nov., novel members of the phylum Bacteroidetes, isolated from soil cultivated with Korean ginseng." International journal of systematic and evolutionary microbiology 56(8): 1777.
Wu, C. L., Lin, H.J., Guo, H.R., Su, S.B. (2007). "Tetramethylammonium hydroxide intoxication." Chinese Journal of Occupational Medicine 14(2): 67-76.
Wu, J., M. Muruganandham, et al. (2007). "Degradation of DMSO by ozone-based advanced oxidation processes." Journal of hazardous materials 149(1): 218-225.
Wu, Y., L. Whang, et al. (2008). "Evaluation of performance and microbial ecology of sequencing batch reactor and membrane bioreactor treating thin-film transistor liquid crystal display wastewater." Water science and technology: a journal of the International Association on Water Pollution Research 58(5): 1085.
Yamaguchi, K., A. Kawamura, et al. (2003). "Characterization of Nitrous Oxide Reductase from a Methylotrophic Denitrifying Bacterium, Hyphomicrobium denitrificans A3151." J Biochem 134(6): 853-858.
You, S. (2005). "Identification of denitrifying bacteria diversity in an activated sludge system by using nitrite reductase genes." Biotechnology Letters 27(19): 1477-1482.
Zinder, S. and T. Brock (1978). "Dimethyl sulfoxide as an electron acceptor for anaerobic growth." Archives of Microbiology 116(1): 35-40.