白姍燕－以臭氧氧化水中有機物之研究
Oxidation of Organic Matters in Aqueous Solution by Ozone
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臭氧為一強氧化劑，亦可被用為飲用水中氯消毒劑之替代品。但臭氧的使用效率常會因水質條件不同而受到干擾。本研究針對不同的水質條件，探討包括臭氧劑量、pH值以及鹼度等進行臭氧氧化水中有機物效率。

對於台大醫院污水處理廠之未加氯放流水，由於水中含有大量顆粒狀有機物及微生物，直接以臭氧進行氧化反應會造成水中NPDOC濃度上升的現象。若先將水中顆粒過濾，則可避免NPDOC濃度上升。當水中臭氧/ NPDOC濃度比大於0.5時，NPDOC的去除效果較佳。而UV₂₅₄吸光度在反應開始的20分鐘內急速下降，顯示臭氧對水中共軛雙鍵物質有極良好之氧化效率。隨著水中鹼度提高，NPDOC的去除率下降，但水樣的pH值對於NPDOC的去除並無明顯影響。唯pH值較高者對NPDOC的去除略有幫助，對 UV₂₅₄吸光物質的分解與反應速率常數則無影響。在經過臭氧反應後，溶液之pH值均趨近於8。

臭氧對於腐植酸與黃酸溶液NPDOC的去除率大約只有50％。對腐植酸而言，臭氧 / NPDOC濃度比為0.3時即可有效降低水中NPDOC；對黃酸而言，此值需為0.5時方可有效降低水中NPDOC。UV₂₅₄吸光度在反應開始的20分鐘之內降低90％，因此可以瞭解臭氧對水中化合物所含之雙鍵則有相當強的分解能力。當鹼度偏高時，臭氧對NPDOC的去除率下降；當pH值偏高時，臭氧對NPDOC的分解效率較好，但對UV₂₅₄吸光度的去除則無影響。隨著腐植酸濃度增加，經臭氧反應後溶液的pH值亦降低。

臭氧氧化並無法有效降低板新水廠原水中NPDOC濃度，對於UV₂₅₄的降解亦有限，主因板新水場原水之有機物濃度偏低之故。臭氧亦無法有效降低六堵水廠原水中NPDOC濃度，但對UV₂₅₄吸光度吸光度之降解則有相當良好之結果。以臭氧對金門原水進行氧化之效率相當好，對NPDOC及UV₂₅₄吸光度的降低均有良好成效。

This study evaluates the effectiveness of ozonation for control of the organic pollutants in water and wastewater. Effect of ozone dosages, initial concentrations of organic matter, pH, and alkalinity were studied.

Direct ozonation of the effluent from hospital wastewater treatment plant indicated that the non-pergeable dissolved organic carbon (NPDOC) was increased if the particulate organic matter (suspended solids) were not removed. However, an 80% removal of the NPDOC was obtained when the water was filtered before the ozonation when O3/NPDOC (mg/mg) was higher than 0.5. It was also observed that 90% of the UV254 absorbance was removed in twenty minutes of ozonation. Alkalinity deteriorates the effectiveness of ozonation. However, no apparent effect from pH was observed in the pH ranges (5-9) tested in this study.
When Aldrich humic acids was used, it is observed that only 50% of NPDOC was removed after ozonation. The optimum ozone dosage was determined to be 0.3 O3/NPDOC (mg/mg). More than 90% of the UV254 absorbance was removed in twenty minutes, as observed in the effluents of treated hospital wastewater. Similar observation was obtained when the fulvic acids extracted from the Aldrich humic acids was used. The pH values of the solutions were decreased after ozonation when humic and fulvic acids were ozonated. For comparison, raw water from Liu-Du, Ban-Hsin, and Kin-Men water treatment plants were also evaluated for the effectiveness of ozonation and the results were discussed in this study.