蔣本基臺灣大學：環境工程學研究所劉鴻擇Liu, Hung-TseHung-TseLiu2007-11-292018-06-282007-11-292018-06-282006http://ntur.lib.ntu.edu.tw//handle/246246/62644摘要 本研究的目的在於評估溴離子與氨氮濃度在臭氧處理程序中對於溴酸鹽生成的影響，進而在加氯消毒處理程序中評估溴離子濃度對於含溴物種的三鹵甲烷(THM)及鹵乙酸類(HAA)生成影響。在臭氧處理程序中，根據溴酸鹽的生成進行溴酸鹽模式預測的推導，並建立最小化溴酸鹽生成的操作方針。 本研究實驗操作可分為以下兩個階段：第一階段為臭氧處理程序，針對臭氧實驗中，溴離子、氨氮、總有機碳、臭氧濃度以及溴酸鹽生成進行分析並建立溴酸鹽預測模式。第二階段為加氯實驗，對於餘氯量與消毒副產物生成潛勢依實驗時間的不同（1、3、6、24、48、168 小時）進行取樣與分析。 研究結果顯示，利用因子分析方法對於澄清湖水質資料分析中，溴離子與溴酸鹽為分類項目中的一個類別，得知溴酸鹽生成與溴離子存在的關係。在臭氧處理程序中，溴酸鹽的生成隨著溴離子與臭氧反應時間的增加而增加。當水體中存有氨氮時，氨氮與次溴酸（HOBr）的反應會降低溴酸鹽的生成，然而臭氧亦會與氨氮反應生成硝酸鹽（NO3-）。因此，氨氮濃度對於溴酸鹽生成的降低有顯著的影響。在加氯實驗中，溴離子濃度對於含溴物種的三鹵甲烷影響較鹵乙酸類明顯。最後經由溴酸鹽預測模式的建立達到溴酸鹽濃度最小化的操作方針，以求符合臭氧處理程序之最終目標。 關鍵字：臭氧化處理程序;溴酸鹽;溴酸鹽預測模式;消毒副產物生成潛勢;三鹵甲烷;鹵乙酸類Abstract The objective of this study is intended to assess the effects of bromide and ammonia concentrations on bromate formation and bromide on bromide-containing THMs and HAAs species and to develop the bromate formation model for establishing operation guideline on minimization of bromate formation. The experiment of work in this study can be divided into two stages. In stage 1, ozonation of water sample was conducted to evaluate reduction of bromide, ammonia, TOC, ozone, and the formation of bromate, and development the bromate formation model. In stage 2 chlorination samples were collected at 1, 3, 6, 24, 48, and 168 hours, respectively, for residual chlorine, THMs, and HAAs analyses. The result of Factor analysis reveals that the group of bromide and bromate is one of the principal components for source water quality parameters at Cheng-Chin Lake. The bromate formation concentration increases with increasing reacting time between ozone and bromide. In principle, in the presence of ammonia, the bromate formation can be reduced due to the reaction of hypobromous acid with ammonia. Since the ammonia can react with ozone to form nitrate, the fraction of the ammonia attributed to reduce the bromate formation in ozonation should be identified. In chlorination process, the effect of bromide concentration on the distribution of bromide-containing THMs species is more significant than that effect on bromide-containing HAAs species. Finally, an integrated bromate formation model was developed and can be utilized as an operation guideline for minimization of bromate formation in the course of ozonation. CE Database subject headings: ozonation, bromate, bromate formation model, DBPFP, THM, HAAContents Chapter I Introduction 1-1 1-1 Background 1-1 1-2 Objectives 1-3 1-3 Major Tasks 1-3 Chapter II Literatures Review 2-1 2-1 Ozonation 2-1 2-2 DBP Formation by Ozonation 2-5 2-2-1 Ozonation By-Products 2-5 2-2-2 Bromate Formation Mechanisms 2-5 2-2-3 Factors affecting Bromate Formation 2-9 2-3 Chlorination 2-15 2-4 DBP Formation by Chlorination 2-16 2-4-1 Chlorination By-Products 2-16 2-4-2 Factors affecting DBP Formation 2-17 Chapter III Materials and Methods 3-1 3-1-1 Research flowchart 3-1 3-1-2 Experimental procedures 3-2 3-2 Experimental Methods 3-3 3-2-1 Experimental Design 3-3 3.2.2 Unit Process 3-7 3-2-3 Analytical Method for DBPs 3-10 3-2-4 Analytical Methods for Residual chlorine, TOC, Bromide and Ammonia 3-20 3-3 Apparatus 3-25 Chapter IV Results and Discussion 4-1 4-1 Water quality background analyses 4-1 4-1-1 Source water quality analyses 4-1 4-1-2 Disinfection by-products analyses 413 4-1-3 Background information analyses 4-17 4-2 Modeling Bromate Formation In The Ozonation Process 4-21 4-2-1 Effect of bromide concentration on bromate formation 4-21 4-2-2 Effect of ammonia concentration on bromate formation 4-25 4-2-3 Development of bromate formation model 4-31 4-3 Chlorination and predictive DBP formation model 4-36 4-3-1 Chlorine demand and chlorine decay model 4-36 4-3-2 Formation potential of THMs and HAAs 4-43 4-3-3 Predictive DBP formation model 4-51 4-4 Comparison of DBPs formation between ozonation and chlorination processes 4-54 4-4-1 Relationship between organic and inorganic DBP formation concentrations 4-54 4-4-2 Effect of bromide-containing compounds on THMs and HAAs 4-58 4-4-3 Strategies on minimization of bromate formation 4-61 Chapter V Conclusions and Recommendations 5-1 5-1 Conclusions 5-1 5-2 Recommendations 5-3 Reference R-1 Appendix A-1 List of Figures Figure 2-1-1 Desired and undesired effects of the ozonation process (von Gunten, 2003). 2-2 Figure 2-1-2 The reaction mechanism of ozone with organic matter in aqueous solutions 2-4 Figure 2-2-1 Reaction of O3 with Br- and OBr- in aqueous solutions 2-7 Figure 2-2-2 Reaction of bromate formation during ozonation in bromide-containing waters: (a) reactions with ozone (b) reactions with ozone and OH radicals. (von Gunten, 1994) 2-8 Figure 2-2-3 Bromate formation mechanism pathways during ozonation: direct and indirect 2-9 Figure 2-2-4 The oxidation mechanisms of molecular ozone and OH radical. The OH radical oxidation mechanism includes reactions of secondary oxidants as CO3- and Br2- 2-11 Figure 2-2-5 Bromate formation during ozonation in the presence of ammonia (Pinkernell and von Gunten, 2001) 2-11 Figure 3-2-1 Procedures of the ozonation tests to determine the formation of bromate at various levels of ozone dose. 3-5 Figure 3-2-2 Procedures of chlorination tests to determine the chlorine decay, THMs, and HAAs concentrations at different chlorine contact time. 3-6 Figure 3-2-3 The experimental apparatus of ozone batch reactor: 3-8 Figure 4-1-1 The turbidity and hardness in the source water from the Cheng-Chin Lake 4-3 Figure 4-1-2 The colour and odor in the source water from the Cheng-Chin Lake 4-3 Figure 4-1-3 The iron and manganese in the source water from the Cheng-Chin Lake 4-5 Figure 4-1-4 The TDS and ammonia-nitrogen in the source water from the Cheng-Chin Lake 4-5 Figure 4-1-5 The bromide in the source water from the Cheng-Chin Lake 4-6 Figure 4-1-6 The nitrate and nitrite in the source water from the Cheng-Chin Lake 4-7 Figure 4-1-7 The coliform group and total bacterial count in the source water from the Cheng-Chin Lake 4-8 Figure 4-1-8 The Chlorophyll a and odorant in the source water from the Cheng-Chin Lake 4-9 Figure 4-1-9 The COD in the source water from the Cheng-Chin Lake 4-10 Figure 4-1-10 The TOC and AOC in the source water from the Cheng Chin Lake 4-11 Figure 4-1-11 The THMs and HAAs formation in the clear well at the Cheng-Chin Lake Waterworks. 4-16 Figure 4-1-12 The bromate formation during the pre- and post-ozonation processes at the Cheng-Chin Lake Waterworks. 4-16 Figure 4-2-1 The bromide reduction at different levels of bromide concentrations in the ozonation process 4-23 Figure 4-2-2 Effect of bromide concentration on bromate formation in the ozonation process 4-23 Figure 4-2-3 The relationship between bromide reduction and bromate formation 4-24 Figure 4-2-4 The reduction of ammonia concentration at 9.0 mg/L of ozone dose 4-26 Figure 4-2-5 The reduction of ammonia concentration at 7.0 mg/L of ozone dose 4-27 Figure 4-2-6 Effect of ammonia concentration on bromide reduction at 9.0 mg/L of ozone dose 4-27 Figure 4-2-7 Effect of ammonia concentration on bromide reduction at 7.0 mg/L of ozone dose 4-28 Figure 4-2-8 Effect of ammonia concentration on bromate formation at 9.0 mg/L of ozone dose 4-30 Figure 4-2-9 Effect of ammonia concentration on bromate formation at 7.0 mg/L of ozone dose 4-30 Figure 4-2-10 DBPs formation mechanism among Br-, NOMs and NH3 in the course of ozonation and chlorination processes 4-31 Figure 4-2-11 Observations and predictions of the bromate formation in this investigation. 4-35 Figure 4-3-1 The residual chlorine and chlorine demand at different reaction times 4-38 Figure 4-3-2 Effect of different bromide concentrations on chlorine demand 4-38 Figure 4-3-3 The relationship between residual chlorine concentration and the predictive model curve of the chlorine decay model 4-42 Figure 4-3-4 Effect of ammonia concentration on THM formation 4-45 Figure 4-3-5 Effect of bromide concentration on THM formation 4-45 Figure 4-3-6 The species distribution of THMs at various levels of ammonia and bromide concentrations. 4-46 Figure 4-3-7 Effect of ammonia concentration on HAA formation 4-49 Figure 4-3-8 The distribution of HAA5 species various levels of ammonia and bromide concentrations 4-49 Figure 4-3-9 The relationship between THM formation and the predictive model curve of THM formation model 4-52 Figure 4-4-1 The DBPs (bromate, THMs, and HAAs) formation measured at various levels of ammonia concentrations 4-56 Figure 4-4-2 The effect of bromide and ammonia concentrations on DBPs (bromate, THMs, and HAAs) formation. 4-56 Figure 4-4-3 The distribution of bromide-containing THMs species at different bromide concentrations. 4-60 Figure 4-4-4 The distribution of bromide-containing HAAs species at different bromide concentrations. 4-60 Figure 4-4-5 Effect of ozonation dose on bromate formation 4-62 Figure 4-4-6 Effect of bromide concentration on bromate formation 4-62 List of Tables Table 2-2-1 Bromine species formed during bromate formation, oxidation states and important oxidants. 2-7 Table 2-2-2 The levels of ammonia concentration with different source water 2-13 Table 3-2-1 The experimental design for the ozonation and chlorination processes. 3-4 Table 4-1-1 The statistics data of the water treatment plant of Cheng Chin Lake 4-12 Table 4-1-2 The DBP concentration statistics data of water treatment plant of Cheng-Chin Lake 4-15 Table 4-1-3 Pearson correlation matrix of the background data in the Cheng-Chin Lake 4-19 Table 4-1-4 The results of Factor analyses for background data 4-20 Table 4-2-1 The kinetics constants for ozone decay and bromate formation models 4-35 Table 4-3-1 Chlorine decay constants for parallel first-order reaction in this investigation 4-40 Table 4-3-2 The deviation between experimental and predictive data in this investigation 4-41 Table 4-3-3 The percentages of four THMs at different levels of ammonia and bromide concentrations. 4-47 Table 4-3-4 The percentages of HAA5 for different ammonia and bromide concentrations. 4-50 Table 4-3-5 THM yield coefficient of different experimental conditions. 4-53 Table 4-3-6 The deviation of THM between experimental data and predictive model. 4-53 Table 4-4-1 The experimental data for bromate, THMs, and HAAs formation during the ozonation and chlorination processes. 4-57 Table 4-4-2 The distribution of bromide-containing DBPs (THMs and HAAs) species. 4-59en-US臭氧化處理程序溴酸鹽溴酸鹽預測模式消毒副產物生成潛勢三鹵甲烷鹵乙酸類ozonationbromatebromate formation modelDBPFPTHHAAthesis