VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY LE THI VAN INTENSIFIED PHOSPHORUS REMOVAL FROM SYNTHETIC WASTEWATER BY LAB-SCALE HORIZONTAL SUB-SURFACE FLOW CONSTRUCTED WETLANDS USING A MIXTURE OF COAL SLAG AND CALCINED FERRALSOLS AS SUBSTRATE MASTER'S THESIS LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY LE THI VAN INTENSIFIED PHOSPHORUS REMOVAL FROM SYNTHETIC WASTEWATER BY LAB-SCALE HORIZONTAL SUB-SURFACE FLOW CONSTRUCTED WETLANDS USING A MIXTURE OF COAL SLAG AND CALCINED FERRALSOLS AS SUBSTRATE MAJOR: ENVIRONMENTAL ENGINEERING CODE: 8520320.01 SUPERVISORS: Principal Supervisor: Dr. NGUYEN THI AN HANG Co-Supervisor: Assoc. SATO KEISUKE Hanoi, 2020 LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com ACKNOWLEDGEMENTS First and foremost, I would like to express my deep gratitudes to Dr. Nguyen Thi An Hang, my Principal Supervisor, who gave me the opportunity to get involved in this interesting research.
She not only provided me valuable advices on this research but also strengthened my research skills, built up my confidence, and encouraged me to overcome all difficulties. It would have been impossible to fulfill this work without her enthusiastic supports. I extend my sincere thanks to Assoc. Sato Keisuke, my Co-supervisor, who gave me practical advices on the feasibility and applicability of my research.
It was very kind of him to give me opportunities to learn about Japanese culture and people, which will definitely be useful for my future. My gratitude is also gone to Dr. Vu Ngoc Duy for his extraordinary supports. I was immensely benefited from his continuous assistance in constructed wetlands setting up and experimental data processing.
My special thanks go to B. Nguyen Thi Xuyen, the project assistant, for her helps with taking care of CWs system during the global COVID-19 pandemic period. For me, she is a sincere friend and I have learnt a lot from her. I would like to acknowledge VNU Vietnam Japan University (VJU), Ritsumeikan University (RITs), and Hiyoshi Corporation for providing me the best conditions to study and have internship in Vietnam and Japan.
Especially, I am so grateful to Prof. Jun Nakajima and Prof. Soda Satoshi for teaching me at VJU and supporting me during my internship in Japan. This research was completed in the laboratory of the Master’s Program in Environmental Engineering (MEE), VNU Vietnam Japan University (VNU-VJU).
I would like to acknowledge Vietnam National Foundation for Science and Technology Development (NAFOSTED) [grant number 105.13, 2018], and Asia Research Center, Vietnam National University, Hanoi (ARC-VNU) and Korea Foundation for Advanced Studies (KFAS) [grant number CA.11A, 2018] for financial supports. i LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com Lastly, I would like to express my deep gratitudes to my parents for raising me with a love of science and supporting me in all my pursuits. My heartfelt thanks go to Son-san for his love, accompanying, and comments on my thesis research. Thank you all my friends, who were MEE Batch 3 students, for unforgettable memories.
Hanoi, June 14th 2020 Le Thi Van ii LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com TABLE OF CONTENTS ACKNOWLEDGEMENTS.i TABLE OF CONTENTS. iii LIST OF TABLES.vi LIST OF FIGURES. vii LIST OF ABBREVIATIONS. 1 CHAPTER 1: LITERATURE REVIEW.
Pig farming in Vietnam. Pig farming development in Vietnam. Environmental concerns of anaerobically treated swine wastewater. Phosphorus pollution and remedy technologies.
Phosphorus significance and environmental concern. Technologies for phosphorus decontamination of anaerobically treated swine wastewater (ATSWW). Classification of constructed wetlands (CWs). Phosphorus removal by different components in CWs.
Advantages and disadvantages of CWs in P removal from wastewater. 26 CHAPTER 2: MATERIALS AND METHODS.28 iii LUAN VAN CHAT LUONG download : add luanvanchat@agmail. Experimental set-up. Constructed wetlands design and operation.
Analytical methods and equipment. Environmental parameters analysis. Calculation and statistical analysis. 44 CHAPTER 3: RESULTS AND DISCUSSION.
Ferrasols calcination for P removal enhancement. Lab-scale Ferralsols calcination. Large-scale Ferralsols calcination. Adsorptive behaviours of calcined Ferrasols.
Factors influencing P adsorption. Characterization of the filter materials. Characterization of natural and calcined Ferralsols. Characterization of coal slag.
Applicability of the investigated filter materials. Treatment performance of sub-surface horizontal flow constructed wetlands. Side-effects of filter materials on HSSF-CWs effluents. 69 CHAPTER 4: CONCLUSIONS AND RECOMMENDATIONS.73 iv LUAN VAN CHAT LUONG download : add luanvanchat@agmail.89 v LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com LIST OF TABLES Table 1.
Treatment efficiency of piggery wastewater by anaerobically treatment in Thua Thien Hue. P removal mechanisms of CWs components. Effect of nutrient uptake by plants on removal of nitrogen and phosphorus (%) in different CWs simulated scenarios. Parameters of real post-anarobically swine wastewater in Hanoi.
Comparison of P adsorption capacity of investigated filter materials. Coparing CF500 produced in lab-scale and large-scale. Langmuir and Freundlich adsorption isotherm constants. P adsortion capacity of different materials.
Mineral composition of NF and CF500 samples. Main chemical compositions of NF, CF500 and CS. Types of vibration peak in NF and CF500. The chemical compositions in CF500 and NF.
Hydraulic properties of CF500 compared with other materials. The chemical compositions in CS. Physical properties of CS compared with other materials. Selection the mixing ratio of CF500 and CS.
The concentration of 6 heavy metals in post-adsorption solutions. 71 vi LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com LIST OF FIGURES Figure 1. Distribution of pig production in Vietnam by ecological regions. P is an important and essential nutrient for plants.
HABs are triggered by nutrient enrichment. Classification of CWs. The diagram of VSSF-CWs. P adsorption mechanism on material surface.
Phytoremediation Using Aquatic Plants. Rhizosphere in CWs plants. Phosphorus cycle in constructed wetland. Source structure of the national electricity system by primary energy 22 Figure 2.
Pha Lai Thermal Power Joint Stock Company. Principle diagram of electricity production technology. Sampling location of Ferralsols in Dak Nong Province. Stone placed at the bottom of CW units.
Sand added on the top of CWs units. Aquatica ipomoea planted from seeds on the soil before being transferred into CW units. Cymbopogon citratus kept alive in the tap water before being transferred into CW units. Aquatica ipomoea at the time being tranferred into CWs.
Preparing NF for calcination with the commcerical furnace. Layers structure of tanks in CWs. Nutrient solution storage tank.38 vii LUAN VAN CHAT LUONG download : add luanvanchat@agmail. The HSSF-CWs system planted with water spinach and lemongrass.
AMRAY Model 1830 Scanning Electron Microscope. X-ray fluorescence spectrometer. UV/Vis Diode Array Spectrophotometer. The pH meter.
The SensION + EC5, Hach, China. Atomic absorption spectrophotometer. Effect of pH of NF and CF500 on P removal. Effect of dosage of NF and CF500 on P removal.
Effect of temperature of CF500 on P removal. The fitting Langmuir and Freundlich isotherm models. 51 for P adsorption by CF500. The fitting Langmuir and Freundlich isotherm models for P adsorption by NF.
The fitting Langmuir and Freundlich isotherm modelts for P adsorption by CS. Linear form of adsorption isortherms: a) Langmuir model and b) Freundlich model of CF500. Linear form of adsorption isortherm following a) Langmuir model and b) Freundlich model of NF. Linear forms of adsorption isortherms: a) Langmuir model and b) Freundlich model of CS.
Kinetic curve of CF500. Kinetic curve of NF. Kinetic curve of of CS. SEM observation for a) NF and b) CF500.
XRD spectrum of NF. XRD spectrum of CF500. 59 viii LUAN VAN CHAT LUONG download : add luanvanchat@agmail. FTIR analysis for NF and CF500.
The P removal efficiency of 4 units of CWs. The change of P concentration in the effluent over the time. pH of post-adsorption solutions. EC of post-adsorption solutions.
71 ix LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com LIST OF ABBREVIATIONS ATP Adenosine triphosphate BOD Biochemical oxygen demand COD Chemical oxygen demand CWs Constructed wetlands DNA Deoxyribonucleic acid DO Oxygen demand FAO Food and agriculture organization FWS-CWs Free water surface constructed wetlands HSSF-CWs Horizontal sub-surface flow constructed wetlands N Nitrogen P Phosphorus RNA Ribonucleic acid SSF-CWs Sub-surface flow constructed wetlands SS Suspended solid TKN Total Kjeldahl nitrogen TP Total phosphate VSSF-CWs Vertical sub-surface flow constructed wetlands x LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com INTRODUCTION According to the Food and Agriculture Organization (FAO), Asia is one of the largest producers and consumers of livestock products (Vu, 2019). The pig breeding industry in Asia develops at a very fast pace but it is mainly spontaneous and has not yet met the technical standards of breeding facilities and breeding techniques (Le, 2014). Therefore, the swine wasteawter normally contains high levels of pathogens, nirogen (N), and phosphorus (P) (Vietnam National Environment Report, 2014). Nowadays, there are variable technologies for treating livestock wastewater such as: The upflow sludge blanket filteration, USBF (Truong, 2010); stabilization lakes (Nguyen, 2011); upflow anaerobic sludge blanket, UASB (Rodrigues, 2010), anaerobic reactor of expanded granular sludge bed - EGSB (Lee, 2012).
In Vietnam, anaerobic treatment is considered an appropriate solution to treat wastewaters containing high contents of organic matter and suspended solids such as swine wastewater. However, this technology is not the final stage in the treatement system to ensure the criteria for safe discharge into the environment (Nguyen, 2012). Therefore, it is necessary to implement additional treatment to swine wastwater after anaerobic treatment before discharging it into the environment. Phosphorus is an important element in all known life forms.
Inorganic P in the form PO43- plays an important role in biological molecules such as Deoxyribonucleic acid (DNA) and Acid ribonucleic (RNA). On the other side, P at high concentration is one of the causes of water pollution with phenomena known as eutrophication and toxic algae. According to QCVN 40: 2011/BTNMT (column B), the discharge limit for P in the industrial wastewater is 6 mg/L. CWs have many advantages, namely simple operation, less maintaining demand, low energy requirement, green teachnology, and especially are suitable for small communities as a decentralized technology (Wu, 2015).
1 LUAN VAN CHAT LUONG download : add luanvanchat@agmail.com In the CWs, P can be removed from wastewater via several pathways, such as sorption onto filter materials, plant uptake and microbial assimilation (Vymazal, 2008). Of which, the role of filter materials is domninant, with the removal mechanisms as follows: adsorption, precipitation, settling, etc. (Wu et al. Regarding the P treatment performance, the horizontal subsurface flow CWs (HSSF-CWs) were found to be more efficient than other types of CWs, such as vertical subsurface flow CWs (VSSF-CWs), free water surface CWs (FWS-CWs) (Arun,2019).
Even in the HSSF-CWs, their P removal ability is usually low and unstable. To overcome this challenge, this study aims at enhancing the P removal efficiency of HSSF-CWs by utilizing a mixture of an industrial by-product (coal slag) and a natural material (Ferralsols) as the filter materials and accumulating plants, namely water spinach (Aquatica ipomoea) and lemongrass (Cymbopogon citratus). To achieve this ultimate goal, a research titled “Intensified phosphorus removal from synthetic wastewater by lab-scale horizontal sub-surface flow constructed wetlands using a mixture of coal slag and calcined ferralsols as substrate” was carried out with the specific objectives as follows: (i) Improve P sorption capacity of raw ferralsols (NF) by calcination, (ii) Investigate the adsorption behaviors, (iii) Evaluate the P treatment performance of the HSSF-CWs using mixture of filter materials and acumulating plants, and (iv) Elucidate possible side-effects of using the selected media in HSSF-CWs. This thesis comprises of 4 main Chapters with the following major contents: Introduction: This part gave the research background, objectives, scope and scale, and research significance.
Literature review: This Chapter provided overall information about environmental problems related to P pollution, the discharge standsards for P containing wastwater, numerous technologies for P decontamination from wastewater. In addition, the composition of swine wastwater after anaerobic treatment was investigated. Especially, this chapter focuses on the CWs, highlighting the roles of filter media and wetland plants. 2 LUAN VAN CHAT LUONG download : add luanvanchat@agmail.
Materials and methods: This Chapter introduced materials, methods and equipments used for this research. Also, the experimental set-up was described in details.