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i Vienglasy Mangnomek INVESTIGATION ON A COMBINATION OF CHEMICAL AND BIOLOGICAL METHODS FOR THE TREATMENT OF PULP AND PAPER MILL WASTEWATER IN VIENTIANE MASTER THESIS Hanoi, November 2011 TECHNICAL UNIVERSITY OF DRESDEN VNU UNIVERSITY OF SCIENCE ii TECHNICAL UNIVERSITY OF DRESDEN VNU UNIVERSITY OF SCIENCE Vienglasy Mangnomek INVESTIGATION ON A COMBINATION OF CHEMICAL AND BIOLOGICAL METHODS FOR THE TREATMENT OF PULP AND PAPER MILL WASTEWATER IN VIENTIANE Major: Waste Management and Contaminated Site Treatment MASTER THESIS SUPERVISOR: ASSOC. PROF. DR. BUI DUY CAM ASSOC. PROF. DR. DO QUANG TRUNG Hanoi, November 2011 iii Table of contents Abbreviations iv List of tables v List of figures vi Abstracts vii Acknowledgement viii Introduction 1 CHAPTER I. LITERATURE STUDY 2 1.1.Status of environmental management in Vientiane 2 1.1.1. Introduction of Vientiane 2 1.1.2. Environmental issues in Vientiane 3 1.1.3. Situation of pulp and paper mill in Vientiane 7 1.2. The pulp and paper mill wastewater treatment technologies 11 1.2.1. Pulp and paper mill production 11 1.2.2. Sources of pollution in the production of pulp and paper mill 12 1.3. Some methods commonly using to treat with the wastewater 15 1.3.1. Physicochemical treatment 15 1.3.2. Membrane filtration 19 1.3.3. Biological treatment 21 CHAPTER II. EXPERIMENT 25 2.1. Research objective 25 2.2. Equipment and Chemicals………………… ……………………………… 26 iv 2.2.1. Equipments 26 2.2.2. Chemicals 26 2.3. Analitycal methods in the study 28 2.3.1. Determination of Chemical Oxygen Demand 28 2.3.2. Determination of Biochemical Oxygen Demand……………………… …29 2.3.3. Analysis of Ammonia content 30 2.3.4. Analysis of Nitrite and Nitrate 31 2.3.5. Procedure for the determination of Phosphate 33 2.4. Preparation of Pulp and paper mill samples 34 2.5. Physicochemical method for the pretreatment of pulp and paper mill wastewater……………………………………………………………………… 35 2.5.1. Coagulation experiments for sample 1 and 2 35 2.5.2. Reduce of COD value by pH change for sample 3 35 2.6. Removal of COD in pulp and paper mill wastewater by combinated Aerobic and Anaerobic circulatory System ……………………………………………….35 2.7. Material filling in column 36 CHAPTER III. RESULTS AND DISCUSSION 39 3.1. Pretreatment of pulp and paper mill wastewater by physicochemical methods39 3.1.1. Coagulation experiments for sample 1 and 2 39 3.1.2. Effect of the pH and PAC doseage to the reduction of COD in sample 3 41 3.2. Investigation of the biological treatment with activated sludge 43 3.2.1. Effect of retention time on COD removal for sample 1 43 3.2.2. Effect of retention time on COD removal for sample 2………………… 44 3.2.3. Effect of retention time on COD removal for sample 3 ………….……….45 3.3. Primary investigation on the treatment of pulp and paper mill wastewater by the combination of circulatory aerobic and anaerobic system 46 v 3.3.1. The reduction of COD 47 3.3.2. The change of Ammonia 48 3.3.3. The change of Nitrite 49 3.3.4. The change of Nitrate…………………………………………………… 50 3.3.5. The change of Phosphrus 51 3.3.6. A proposed model for pulp and paper mill wastewater treatment for Vientaine factories 52 Conclusions 54 References ……………………………………………………………………….55 vi Abbreviations AC Anaerobic Contact process AF Anaerobic Filter AOX Adsorbable organic halogens BOD Biological Oxygen Demand COD Chemical Oxygen Demand CSOCA&A Circulatory system of combination of Aerobic and Anaerobic DO Dissolved Oxygen MLSS Mixed Liquor Suspended Solids PAC Poly Aluminum Chloride TSS Total suspended solids vii List of tables Table 1. Wastewater Quality in Vientiane Capital Jan-Dec 2000[2]………… …5 Table 2. Industrial Growth in Lao PDR [2]………………………………… ……6 Table 3.Pollutants in the wastewater in the factory’s ponds[8]………………… 8 Table 4. Typical efficiencies of aerobic systems [9]…………………………… 22 Table 5. Anaerobic degradability of pulp and paper mill wastewater[19]… … 23 Table 6. Data of standard curve 30 Table 7. Data of ammonia standard curve……………………………………….32 Table 8. Data of nitrite standard curve making………………………………… 33 Table 9. Data of nitrate standard curve……………………………………… …34 Table 10. Data of phosphorus standard curve………………………………… 35 Table 11. Effect of PAC dosage to COD reduction for sample 1…………….….41 Table 12. Effection of coagulant PAC to COD removal …………………… …42 Table 13. Effection of pH changed to COD removal……………………………44 Table 14. Effection of coagulant PAC to COD removal ……………………… 44 Table 15. Data of effection of aerobic to COD removal ……………………… 46 Table 16. Data of effection of aerobic to COD removal…………………………47 Table 17. Data of effection of aerobic to COD removal…………………………48 Table 18. Data of effection of CSOCA&A to COD removal…………………….49 Table 19. Data of effection of CSOCA&A to NH 4 + due to times……………… 51 Table 20. Data of effection of CSOCA&A to NO 2 2- due to times……………… 51 Table 21. Data of effection of CSOCA&A to Nitrate due to times………………52 viii Table 22. Data of effection of CSOCA&A to Phosphorus due to times……… 53 List of figures Figure 1. Map of Lao PDR………………………………………………… ….2 Figure2 . Source flowchart from the production line in KPS paper mill in Laos [8]………………………………………………………………….……… 10 Figure 3. Process description for pulp and paper mill factory[10]………….… 12 Figure 4. Pollutants from various sources of pulping and papermaking [11]…………………………………………………………………………….….15 Figure 5. Diagram of Flocculate w11………………………………………… 27 Figure 6. Diagram of Aerobic system W11………………………………………27 Fignure 7. COD standard curve 30 Figure 8. Ammonia standard curve…………………………………….……… 32 Figure 9. Nitrite standard curve……………………………………………… …33 Figure 10. Nitrate standard curve………………………………………….…… 34 Figure 11. Phosphorus standard curve……………………….…………….…….35 Figure12. Diagram of combining Anaerobic and Aerobic system………… … 38 Figure 13 : Surface of porous material………………………………………… 39 Figure14. Microorganism layer……………………………………………… …38 Figure 15. Membrane of porous material after three times circularly pumping water containing nutrient……………………………………………………… 38 Figure 16. Diagram of effection of PAC dosage to COD removal………… …38 Figure 17 Diagram of effection of coagulant PAC to COD removal…………….41 Figure 18. Diagram of effection of pH changed to COD removal… 42 Figure 19. Diagram of effection of coagulant PAC to COD removal………… 43 ix Figure 20. Diagram of effection of aerobic to COD removal…………….… … 44 Figure 21. Diagram of effection of aerobic to COD removal……………….……45 Figure 22. Diagram of effection of aerobic to COD removal……………….……46 Figure 23. Diagram of effection of aerobic to COD………………………… …48 Figure 24. Diagram of effection of aerobic to Ammonia………………….…… 49 Figure 25. Diagram of effection of aerobic to Nitrite………………………… 50 Figure 26. Diagram of effection of aerobic to Nitrate……………………………51 Figure 27. Diagram of effection of aerobic to Phosphrus…………………… …51 Figure 28 : A purposed model wastewater treatment process using activated sludge…………………………………………………………………….…… 54 x Abstract Lao PDR is a country rich in natural resources and its water resources are vital in providing the basic needs for its people, socio-economic development of the country. The scale and extent of environment problems in the urban areas of Vientiane is relatively small compared to other cities in the region due to its relatively small size and population, low population density, and relatively low level of industrial activity. However, there are some water pollution problems in major urban areas caused by various water uses by communities (households, hotels, hospitals and entertainment centers). In addition, the actions of the agricultural and industrial sectors have resulted in water pollution, including mineral exploitation, pulp and paper mills factories and hydropower generation. Therefore, in accordance with the Millennium Development Goals, the government set targets in order to improve the local people’s access to safe drinking water by the years 2015. For in Vientiane is one looking for manage methods for treatment wastewater discharges. In this study, the situation of environmental pollution in Vientiane in general and from the pulp and paper mill wastewater in particularly was evaluated. These are recognized that the environmental issues in Vientiane having problem. The wastewater samples were collected from pulp and paper mill factories in Laos and Vietnam for the experiments in laboratory of Environmental Chemistry, Hanoi University of Science. The physicochemical and biological methods for the treatment of wastewater were investigated. The results shown that, the pulp and paper mill wastewater can be pretreated by the reduction of pH with dilute H 2 SO 4 acid at pH = 3; and by the coagulation with poly aluminum chloride (PAC). The COD removal from 74.21% of sample 1 and 62.16% of sample 3. Then the wastewater samples can be treated by using combined aerobic and anaerobic system with efficiency of COD removal 94.99% of anaerobic and 90% for aerobic