声明
Acknowledgement
摘要
Abstract
Table of contents
List of Figures
List of Tables
Acronyms and abbreviations
1.Chapter one:Introduction and thesis structures
1.1 General Introduction
1.2 General view of water resources and water pollution in China
1.3 Problem statement and definitions
1.4 Objectives of the research
1.5 Scope of the study
1.6 Thesis organization
2.Chapter two:Literatures review and background
2.1 Introduction
2.2 Anaerobic treatment process
2.2.1 Principle of anaerobic treatment
2.2.2 Main conversion processes of organic matter in anaerobic reactor
2.2.3 High rate anaerobic reactors
2.2.4 Anaerobic filter
2.2.5 Important factors affecting anaerobic treatment efficiency
2.2.6.Advantage and disadvantages of anaerobic filter
2.3 Biological nutrients removal(BNR)
2.3.1 Principle of biological nitrogen removal
2.3.2 Enhanced biological phosphorus removal
2.4 Constructed wetlands
2.4.1 General background of constructed wetlands
2.4.2 Type of constructed wetlands
2.4.3 Pollutants removal processes in the constructed wetlands
2.4.4 Role of constructed wetland plants
3.Chapter three:Material and methods
3.1 Introduction
3.2 Process description
3.3 System operation
3.4 Experimental setup
3.4.1 A pilot scale of the modified anaerobic-anoxic-oxic(A2/O)process
3.4.2 A laboratory scale of the modified A2/O process
3.4.3 Constructed wetland
3.5 Wastewater characteristics,analytical techniques and system operation
3.5.1 Raw wastewater characteristics
3.5.2 Analytical methods
3.5.3 Seeding and start-up period of the system reactors
3.5.4 Taguchi orthogonal array design
3.6 Summary
4. Chapter four:Performance evaluation of the modified A2/O process for rural domestic wastewater treatment at ambient temperature
4.1 Introduction
4.2 Brief background of A2/O process
4.3 Material and methods
4.3.1 Experimental system and operation
4.3.2 Domestic wastewater characteristics and analytic items
4.4 Results and discussions
4.4.1 Profiles of operational parameters of UAF treatment process
4.4.2 Anoxic/Oxic treatment process efficiency
4.4.3 Overall treatment performance of the modified A2/O process
4.5 Summary
5.Chapter five:Application of Taguchi orthogonal array design for optimization the COD removal process
5.1 Introduction
5.2 Material and methods
5.2.1 Experimental setup
5.2.2 Taguchi orthogonal array(TOA)method
5.2.3 Analytical methods
5.3 Taguchi results and discussions
5.3.1 General linear model
5.3.2 Effect of pH on the COD removal process
5.3.3 Effect of the temperature on the COD removal process
5.3.4 Effect of HRT on the COD removal process
5.3.5 Effect of the OLR on the COD removal process
5.3.6 Prediction of the optimum COD removal efficiency
5.4 Long term performance efficiency of the UAF reactor
5.5 Evaluation of water dropping height in the oxic reactor regarding to NH4+ removal
5.6 Long term performance efficiency of an integrated A/O process
5.7 Summary
6.Chapter six:Performance efficiency of the horizontal subsurface flow constructed wetland
6.1 Introduction
6.2 Constructed wetlands background
6.3 Material and methods
6.3.1 Preparation of constructed wetland and test procedures
6.3.2 Raw wastewater eharaeteristics
6.4 Plants growth parameters
6.5 Performance efficiency of the constructed wetland
6.5.1 COD removal efficiency
6.5.2 TN and NH4+-N removal efficiency
6.5.3 TP removal efficiency
6.6 Summary
7.Chapter seven:Overall assessment of the bio-ecological combined system performance efficiency for rural domestic wastewater treatment
7.1 Introduction
7.2 Efficiency of the bio-ecological combined system in COD removal
7.3 Efficiency of the bio-ecological combined system in TN removal
7.4 Efficiency of the bio-ecological combined system in NH4+-N removal
7.5 Efficiency of the bio-ecological combined system in TP removal
7.6 Summary
8.Chapter eight:Conclusions and Recommendations
8.1 Conclusions
8.2 Recommendations
References
List of Publications