本研究利用高級氧化方法進行預處理(如UV/PS處理及臭氧處理)，並結合好氧生物處理來處理不易生物降解的有機物(如EDTA)，針對UV/PS及臭氧這兩項程序進行研究，並比較兩項程序對EDTA及金屬-EDTA的去除效率。利用UV對Persulfate (PS)於30分鐘的光催化反應下及相對於100%的理論PS完全氧化EDTA的劑量 (即PS與EDTA莫爾比為17:1)，進行光催化處理EDTA及金屬-EDTA廢水，於EDTA、Fe(II)EDTA和CuEDTA的廢水中TOC去除率分別為68.46%、30.97%及94.96%，並將pH調整到7時，銅跟鐵的去除率分別為95.34%及97.61%。然而利用臭氧程序處理EDTA及金屬-EDTA最高的TOC去除率只有10%，銅跟鐵的去除率幾乎為零，由於反應時間太短，導致無法行成氫氧根降解EDTA及金屬-EDTA。
利用UV/PS程序對EDTA及金屬-EDTA進行預處理並結合好氧生物程序進一步處理，在EDTA的廢水中，PS劑量為30%的理論COD、在Fe(II)EDTA的廢水中，PS劑量為10%的理論COD。經由UV/PS進行預處理再用好氧生物處理進一步處理，EDTA廢水及Fe(II)EDTA的TOC去除率皆可達到60%， 將有機負荷率分別控制在1 kg/m3-day 及0.5 kg/m3-day於EDTA及Fe(II)EDTA的廢水。未進行預處理及利用臭氧處理方法進行預處理的TOC去除率僅僅1%，但採用UV/PS進行預處理時，TOC去除效率可以達60%。

In this study, pre-treatment processes such as ozonation and photocatalysis of persulfate (UV/PS), followed by aerobic biological treatment process were employed to treat recalcitrant organic substances, i.e., EDTA and metal-EDTA wastewater. In the UV/PS process, the removal of TOC reached 68.46, 26.75, and 93.16% for EDTA, Fe(II)EDTA, and CuEDTA, respectively, and after adjusting pH to 7 the removal of Cu and Fe was 95.34% and 97.61%, respectively, at PS:EDTA molar ratio of 17:1 corresponding to 100% of the theoretic PS dosage required to oxidize EDTA completely and irradiation time of 30 min. Meanwhile, the highest removal of TOC using ozonation process was only 10% for both EDTA and metal-EDTA and Cu and Fe removal were negligible. It is due to insufficient reaction time for generating enough OH• to degrade EDTA and metal-EDAT.
With the UV/PS pre-treatment process using 30% and 10% of the theoretical PS dosage required for complete oxidation of the theoretical COD for EDTA wastewater and Fe(II)EDTA wastewater, respectively.  TOC removal was 60% with the organic loading rate of 1 kg/m3-day for EDTA wastewater and removal was 60% with organic loading rate of 0.5 kg/m3-day for the Fe(II)EDTA wastewater. The TOC removal using aerobic process without pre-treatment or using ozone pre-treatment were negligible (∼1%).

Acknowledgements                                                                                                                                       i
中文摘要                                                                                                                                                      ii
Abstract                                                                                                                                                      iii
Contents                                                                                                                                                vi
List of Tables                                                                                                                                            viii
List of Figures                                                                                                                                               ix
1 Introduction                                                                                                                                              1
1.1 Background information                                                                                                                         1
1.2 Objectives                                                                                                                                     2
1.3 Research scope                                                                                                                                      3
2 Literature reviews                                                                                                                                      4
2.1 Wastewater containing CuEDTA or FeEDTA                                                                                        4
2.2 Advanced oxidation processes (AOPs) for the treatment of metal-EDTA complexes                      5
2.2.1 Electro-Fenton or Fenton process                                                                                                      6
2.2.2 PS related process                                                                                                                         7
2.2.3 Ozone process                                                                                                                                10
2.3 Biological treatment process                                                                                                              11
3 Materials and Methods                                                                                                                          13
3.1 Chemicals and materials                                                                                                                 13
3.2 Experimental setup and procedures                                                                                                       13
3.2.1 UV/PS process                                                                                                                                 13
3.2.2 Ozonation process                                                                                                                        15
3.2.3 Integration of physical-chemical and biological processes                                                                     17
3.3 Analytic methods                                                                                                                        19
3.3.1 HPLC for EDTA analysis                                                                                                               19
3.3.2 Chemical oxygen demand (COD)                                                                                                          20
3.3.3 TOC                                                                                                                                                   21
3.3.4 Flame atomic adsorption spectrophotometer                                                                                   21
4 Results and Discussion                                                                                                                          22
4.1 UV/PS process                                                                                                                                           22
4.1.1 Treatment of EDTA                                                                                                                         22
4.1.2 Treatment of CuEDTA                                                                                                                      27
4.1.3 Treatment of Fe(II)EDTA                                                                                                                   31
4.2 Comparison of TOC removal for CuEDTA, FeEDTA and EDTA by UV/PS process                   35
4.3 Ozonation process                                                                                                                         37
4.4 Biological process                                                                                                                               38
4.4.1 Biological process for EDTA without pre-treatment                                                                  38
4.4.2 Biological process for EDTA and Fe(II)EDTA with pre-treated by UV/PS process                  39
4.4.3 Biological process for EDTA with pre-treated by ozonation process                                        42
5 Conclusions                                                                                                                                            44
5.1 Conclusions                                                                                                                                                   44
5.2 Recommendations                                                                                                                             45
References                                                                                                                                                    46

List of Tables
2.1	The effect of metal-EDTA stability constants in electro-Fenton process [30]                              7
2.2	Compare the decomplexation of CuEDTA using UV/PS and UV/H2O2                                     10
3.1	PS dosage related with EDTA molar ratio and COD mass ratio                                                        15
3.2	Ozone dosage using ozone generator                                                                                        17
3.3	COD concentration of EDTA                                                                                                      21

List of Figures
3.1	Scheme of the UV system                                                                                                                 14
3.2	Scheme of the ozone system                                                                                                       16
3.3	Schematic of aerobic system                                                                                                     18
3.4	EDTA standard curve                                                                                                                20
4.1	TOC removal as function of time under the different of PS dosage (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for com- plete oxidation of EDTA). Experimental conditions: EDTA = 1 mM.  (a)Initial pH = 7. (b) Initial pH = 5. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                                         23
4.2	TOC removal as function of pH under the different of PS dosage (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for com- plete oxidation of EDTA). Experimental conditions: EDTA = 1 mM. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                                                                                                      25
4.3	The variation of pH as a function of PS dosage (0%, 25%, 50%,  75%,  100%, and 125% of theoretic dosage required for complete oxidation of EDTA).  (a) Initial pH = 7.  (b) Initial pH  = 5                                                                                                                                                      26
4.4	TOC removal as a function of time under different of PS dosages (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for com- plete oxidation of CuEDTA). Experimental conditions: EDTA = 1 mM. Cu:EDTA molar ratio = 1:1. Initial pH = 2.7. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                         28
4.5	The variation of pH as a function of PS dosage (0%, 25%, 50%,  75%,  100%, and 125% of theoretic dosage required for complete oxidation of CuEDTA). Reaction time = 60 min               29
4.6	Cu species as a function of pH. Modelled using Mineql+. Cu concentration = 1 mmole/L                         30
4.7	Cu removal as function of time under the different of PS dosage (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for complete oxidation of CuEDTA). Experimental conditions: EDTA = 1 mM. Cu:EDTA molar ratio = 1:1. Initial pH = 2.7. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                         30
4.8	Cu removal with TOC removal correlation. Experimental conditions: EDTA = 1 mM. Cu:EDTA molar ratio =  1:1.  Initial  pH  =  2.7.  UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                                                                                      31
4.9	TOC removal as function of time under the different of PS dosage (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for complete oxidation of Fe(II)EDTA). Experimental conditions: EDTA = 1 mM. Initial pH = 2.5. UV radiation (wavelength 254 nm) =8 W. Radiation density = 72 mW/cm2                                                                                                         32
4.10	The variation of pH as a function of PS dosage (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for complete oxidation of Fe(II)EDTA)                                                                 33
4.11	Fe-EDTA species as a function of pH. (a) Fe(II)  system.  (b)  Fe(III) system. Modelled using Mineql+. Fe:EDTA molar ration of 1:1. Fe concentration = 1 mmole/L                                          34
4.12	Fe removal as function of time under the different of PS dosage (0%, 25%, 50%, 75%, 100%, and 125% of theoretic dosage required for complete oxidation of Fe(II)EDTA). Experimental conditions: EDTA = 1 mM. Initial pH = 3. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                                                 35
4.13	TOC removal as a function of PS:EDTA molar ratio for metal-complexed EDTA and EDTA. Experimental conditions: EDTA = 1 mM. Metal:EDTA molar ratio = 1:1. Reaction time = 30 min. pH = neutral pH. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                                                                                              36
4.14	TOC removal as a function of ozone dosage for EDTA, CuEDTA and Fe(II)EDTA by ozonation process. Experimental conditions: EDTA = 1 mM. Metal:EDTA molar ratio = 1:1. Solution volume = 0.3 L. Reaction time = 60 min. pH = neutral pH. Ozone flow rate = 10.53 mg O3/min                                                                                                                                                   38
4.15	TOC removal as a function of Days for EDTA by biological process. Experimental conditions: EDTA = 1 mM. pH = 8. Organic loading rate = 0.5 kg/m3-day                                                39
4.16	TOC removal as a function of days for (a) EDTA and (b) Fe(II)EDTA were pre-treated by UV/PS process. Experimental conditions: EDTA = 1 mM. pH = 8. (a) Organic loading rate = 1 kg/m3-day. (b) Organic loading rate = 0.5 kg/m3-day. (a) PS dosage = 30%  of  COD.  (b)  PS dosage = 10% of COD UV irradiation time = 30 min. UV radiation (wavelength 254 nm) = 8 W. Radiation density = 72 mW/cm2                                                                                                             41
4.17	TOC removal as a function of days for EDTA was pre-treated by ozona- tion process. Experimental conditions: EDTA = 1 mM. Aeration time = 35 min. pH = 8. Ozone flow rate = 10.53 mg O3/min                                                                                                                                    43

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