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VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY NGUYEN THI THUONG STUDY ON POTENTIAL FILTER MATERIALS FOR USE AS SUBSTRATE IN CONSTRUCTED WETLAND TO STRENGTHEN PHOSPHORUS TREATMENT PERFORM[.]
VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY NGUYEN THI THUONG STUDY ON POTENTIAL FILTER MATERIALS FOR USE AS SUBSTRATE IN CONSTRUCTED WETLAND TO STRENGTHEN PHOSPHORUS TREATMENT PERFORMANCE FROM SWINE WASTEWATER MASTER'S THESIS Hanoi, 2019 VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY NGUYEN THI THUONG STUDY ON POTENTIAL FILTER MATERIALS FOR USE AS SUBSTRATE IN CONSTRUCTED WETLAND TO STRENGTHEN PHOSPHORUS TREATMENT PERFORMANCE FROM SWINE WASTEWATER MAJOR: ENVIRONMENTAL ENGINEERING CODE: PILOT SUPERVISORS DR NGUYEN THI AN HANG ASSOC PROF DR SATO KEISUKE DR VU NGOC DUY Hanoi, 2019 ACKNOWLEDGMENTS First of all, I would like to express my heartfelt gratitude to my principal supervisor, Dr Nguyen Thi An Hang for giving me a chance to explore an exciting research field – the constructed wetlands, for always inspiring me She has spent plenty of time for teaching, explaining hard questions as well as sharing her own experiences in approaching and solving research problems Thanks to that, I was well equipped with essential knowledge and skills to fulfill my research I also express my deepest thanks to Assoc Prof Dr Sato Keisuke, who provided me a great guidance during my internship Besides teaching, providing knowledge and enthusiastic support, he always treated me tenderly likes my father In addition, he helped me not to be confused when I first arrived in Japan My special thanks go to Dr Vu Ngoc Duy, who gave me valuable supports in developing research methods, implementing experiments, and deepening my research The second, I want to send my sincere thanks to VNU Vietnam Japan University (VJU), Ritsumeikan University (RITs), Shimadzu Corporation and Shigaraki Center for warm welcome and enthusiastic support during my internship in Japan Without their precious supports, I would not be able to complete this research Especially, I would like to convey my devoted appreciation to Prof Dr Jun Nakajima, Assoc Prof Dr Hiroyuki Katayama, for teaching and supporting me during my study at VJU This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 105.99-2018.13, 2018, Asean Research Center (ARC) research grant of Vietnam National University, Hanoi (VNU), and Japan International Cooperation Agency (JICA) Last but not least, my profound gratitude goes to my family for their spiritual supports during my thesis writing and my daily life as well This accomplishment would not have been possible without them Hanoi, May 31th, 2019 Nguyen Thi Thuong i TABLE OF CONTENTS ACKNOWLEDGMENTS i TABLE OF CONTENTS ii LIST OF TABLES iv LIST OF FIGURES iv LIST OF ABBREVIATIONS .v INTRODUCTION CHAPTER LITERATURE REVIEW 1.1 Phosphorus (P) pollution and its consequences 1.2 Regulations related to P removal 1.3 Phosphorus treatment technologies .11 1.4 Constructed wetlands (CWs) system for wastewater decontamination 19 1.4.1 Definition 19 1.4.2 Classification .19 1.4.3 Application of CWs in wastewater treatment .23 1.4.4 Factors influencing the CWs treatment performance 25 1.4.5 Mechanisms of P removal in CWs 29 1.5 Removing P by substrates in CWs 31 1.6 Overview of research objects .33 1.6.1 Swine waste water .33 1.6.2 Ca-rich bivalve shell as the substrate in CWs 35 CHAPTER MATERIALS AND RESEARCH METHODOLOGY 41 2.1 Materials and equipment 41 2.2 Experiment setting up 45 2.2.1 Modification of materials 45 2.2.2 Characterization of the developed material .46 2.2.3 Adsorption experiments 49 2.2.4 Removal of P from synthetic wastewater using the integrated CWs- adsorption system 51 ii 2.3 Analytical methods .53 2.3.1 Phosphorus analysis 53 2.3.2 Other parameters analysis 53 2.4 Data statistical analysis .53 CHAPTER RESULTS AND DISCUSSION 55 3.1 Screening of filter materials for use as substrate in CWs 55 3.1.1 Comparing potential materials based on P adsorption capacities 55 3.1.2 Comparing filter materials based on their permeability 57 3.1.3 Comparing filter materials based on their side effects 58 3.1.4 Selection of potential filter materials .62 3.2 Intensive investigation of the selected filter materials –white hard clam (WHC) 64 3.2.1 Identification of the optimal modification conditions of WHC 64 3.2.2 Physicochemical properties 66 3.2.3 Batch experiment 70 3.2.4 Column experiment 80 3.2.5 Comparing the P removal efficiency of modified white hard clam (WHC-M800) in the synthetic and real swine wastewater .82 3.3 The P treatment performance in the integrated CWs – adsorption system 83 CHAPER CONCLUSION AND RECOMMENDATION .88 4.1 CONCLUSION 88 4.2 RECOMMENDATION 89 REFERENCES 90 APPENDICES 108 Appendix 1: Visiting some CW systems during internship in Japan 108 Appendix 2: Preparing WHC as the substrate in CWs 109 Appendix 3: Designing and operating the integrated CW-adsorption system .110 iii LIST OF TABLES Table 1.1 Effluent discharge standards of different countries Table 1.2 Phosphorus removal efficiencies of different methods 17 Table 1.3 Mechanism of phosphorus removal in constructed wetland system 30 Table 1.4 Some filter media used for P removal 32 Table 1.5 The main composition of swine wastewater after anaerobic digestion by biogas chamber 34 Table 1.6 The main chemical compositions of bivalve shells and limestone 37 Table 1.7 Some studies used bivalve shell for P removal 39 Table 3.1 Phosphorus adsorption capacity of different materials 57 Table 3.2 Permeability constant (K) of investigated materials 58 Table 3.3 The concentration of heavy metals released from materials 61 Table 3.4 Summary of the obtained scores for investigated materials Error! Bookmark not defined Table 3.5 Effect of calcination temperature .65 Table 3.6 Effect of the calcination time 66 Table 3.7 Brunauer Emmett Teller (BET) analysis 67 Table 3.8 Elemental content of WHC .68 Table 3.9 Elemental content of WHC-M800 68 Table 3.10 Langmuir and Freundlich adsorption isotherm constants .78 Table 3.10 P adsorption capacity at different conditions 81 Table 3.11 Parameters of real post-biogas swine wastewater in Chuong My, Hanoi 83 Table 3.12 The phosphorus concentrations before and after treatment with horizontal flow lab-scale constructed wetlands 85 Table 3.13 The phosphorus removal efficiency and pH after treatment with horizontal flow lab-scale constructed wetlands 86 iv LIST OF FIGURES Figure 1: Thesis‘s outline Figure 1.1 Eutrophication from phosphorus contamination Figure 1.2 The treatment technologies for phosphorus removal .11 Figure 1.3 Metabolic pathways of PAO under aerobic and anaerobic conditions 15 Figure 1.4 The classification of CWs used in wastewater treatments 19 Figure 1.5 The schematic surface flow constructed wetland 20 Figure 1.6 The schematic vertical flow constructed wetland 21 Figure 1.7 The schematic horizontal flow constructed wetland 21 Figure 1.8 The schematic hybrid constructed wetland 22 Figure 1.9 Phosphorus cycle in constructed wetland .29 Figure 1.10 The main clam species in Vietnam .37 Figure 2.1 Images of investigated filter materials 41 Figure 2.2 The routine to Thai Binh shellfish Co., Ltd, Tien Hai Thai Binh 42 Figure 2.3 Procedure to prepare WHC as phosphorous adsorbent 43 Figure 2.4 The pig farm in Chuong My, Hanoi .44 Figure 2.5 Equipments used in this study 45 Figure 2.7 The experiment setting according to Darcy law .47 Figure 2.8 Procedure for determine of porosity .47 Figure 2.9 Small column adsorption test 51 Figure 2.10 Integrated CWs-adsorption systems 52 Figure 2.11 Calibration curve for phosphorus analysis 53 Figure 3.1 Comparison of P adsorption capacity of investigated filter materials 56 Figure 3.2 pH of post-adsorption solutions 59 Figure 3.3 Images of raw WHC and WHC modified at different temperatures 65 Figure 3.4 SEM observation for WHC .67 Figure 3.5 SEM observation for 67 Figure 3.6 EDX spectrum of WHC 68 Figure 3.7 EDX spectrum of WHC-M800 .68 v Figure 3.8 FTIR analysis for WHC 69 Figure 3.9 FTIR analysis for WHC WHC-M800 69 Figure 3.10 Effect of pH of WHC on phosphorus removal 71 Figure 3.11 Effect of pH of WHC-M800 on phosphorus removal 71 Figure 3.12 Effect of dosage of WHC on phosphorus removal 73 Figure 3.13 Effect of dosage of WHC-M800 on phosphorus removal 73 Figure 3.14 Effect of temperature of WHC on phosphorus removal .74 Figure 3.15 Effect of temperature WHC-M800 on phosphorus removal 74 Figure 3.16 The fitting of isotherm models to P adsorption onto WHC .77 Figure 3.17 The fitting of isotherm models to P adsorption onto WHC-M800 .77 Figure 3.18 Linear form of adsorption isotherm following Langmuir of WHC 77 Figure 3.19 Linear form of adsorption isotherm following Freundlich of WHC 77 Figure 3.20 Linear form of adsorption isotherm following Langmuir of WHC-M800.78 Figure 3.21 Linear form of adsorption isotherm following Freundlich of WHC-M800 .78 Figure 3.22 Kinetic test of WHC 79 Figure 3.23 Kinetic test of WHC-M800 79 Figure 3.24 Breakthrough curve of WHC-M800 for P removal under the different flowrate .81 Figure 3.25 Breakthrough curve of WHC-M800 for P removal under the different initial concentration 81 Figure 3.26 Breakthrough curve of WHC-M800 for P removal under the different weight of material .81 Figure 3.28 P adsorption capacity of WHC-M by real wastewater and synthetic wastewater 83 Figure 3.29 The change of phosphorus in the effluent over the time 85 vi LIST OF ABBREVIATIONS BET Brunauer emmett teller BOD Biological oxygen demand COD Chemical oxygen demand EBPR Enhanced biological phosphorus removal EPA Environmental Protection Agency FTIR Fourier transform infrared spectroscopy HAP Hydroxyapatite HLR Hydraulic loading rate HRT Hydraulic retention time MAP Magnesium ammonium phosphate hexahydrate MBRs Membrane bioreactor PAOs Polyphosphate accumulating organisms RO SEM USEPA WHC WWTP Reverse osmosis Scanning electron microscopy United States environmental protection agency White hard clam Wastewater treatment plant vii INTRODUCTION Background Swine breeding industry is an important part of agriculture sector in Vietnam In recent years, numerous large scales of pig farms have been developed to meet the pork demand in the market According to General Statistics Office of Vietnam (2018), the whole country has about 500,000 livestock households, over 29 million pig heads, 3.8 million tons of meat Also, as the pig producer, Vietnam is the biggest in ASEAN and the seventh biggest in the world The swine breeding industry has promoted the economic development as well as the GDP of the country Despite the huge economic benefits, pig breeding industry makes many environmental problems, which negatively affect to human health and ecosystems That is because swine wastewater normally contains high concentration of nutrients, such as phosphorus (P) and nitrogen (N) that are main reasons for eutrophication (Wang et al., 2013) Currently, the most common method for swine wastewater treatment is anaerobic digestion using biogas chamber However, according to several studies, the concentration of pollutants in the effluent after biogas treatment is still very high, exceeding the permitted discharge standards (National Institute of Animal Husbandry, 2015) Thus, further treatment is necessary to ensure the concentration of P in the effluent meets requirements (Ngo, 2013; Nguyen, 2016) Among several technologies utilized for swine wastewater treatment, constructed wetland has shown a promising technology Constructed wetlands (CWs) have been applied as a green technology to treat various kinds of wastewater This technology is gaining much attention of scientists in all over the world, especially in developing countries (Wu et al., 2015) That is because CWs have many advantages, such as low cost, simple operation, high removal efficiency, high biodiversity value, and great potential for water and nutrient reuse (Kadlec, 2009; Vymazal, 2007; Zhang, 2014) Table 1.7 Some studies used bivalve shell for P removal Materials Cockle shell Mussel shell Modification condition P initial P adsorption R removal concentration capacity efficiency (mg/L) (mg/g) (%) Type of wastewater 750oC, 1h 0.85 – 2.21 87.63 Shrimp farm effluent No 0.85 – 2.21 43 Shrimp farm effluent No 0.5-5 1.04 88 Synthetic wastewater No 0.5 1.8 60 Synthetic wastewater 550 oC, 15min 0.5 2.2 77 700 oC, 20min 20 6.15 55 39 Synthetic wastewater Synthetic wastewater Size (mm) Study type Reference Lab-scale Aopreeya et al., 2013 Lab-scale Aopreeya et al., 2013 powder Lab-scale Kim et al., 2018