Options for reuse of nutrients from waste water in the Mekong Delta, Vietnam [Elektronische Ressource] / von Ute Arnold

Ute Arnold

Informations

• Publié par: rheinische_friedrich-wilhelms-universitat_bonn
• Publié le: 01 janvier 2010
• Nombre de lectures: 19
• Langue: Deutsch
• Poids de l'ouvrage: 1 Mo

Extrait

Institut für Nutzpflanzenwissenschaften und Ressourcenschutz
Options for reuse of nutrients from waste water
in the Mekong Delta, Vietnam
Inaugural Dissertation
zur
Erlangung des Grades
Doktor der Agrarwissenschaften
(Dr. agr.)
der Hohen Landwirtschaftlichen Fakultät
der
Rheinischen-Friedrich-Wilhelms-Universität
zu Bonn
vorgelegt am 28.8.2009
von
Ute Arnold
aus
Kempten (Allgäu)1. Referent: PD Dr. Joachim Clemens
2.Prof. Dr. Wolfgang Büscher
Tag der Promotionsprüfung: 17.12.2009
Erscheinungsjahr: 2010
Diese Dissertation ist auf dem Hochschulschriftenserver der ULB Bonn
http://hss.ulb.uni-bonn.de/diss_online elektronisch publiziert.Content and Lists
Content
List of Tables ......................................................................................................................VII
Abbreviations and Technical Terms.................. XII
1. Introduction ...................................................................................................................1
1.1. Motivation..................1
1.2. Workflow...................3
2. Status Quo in the Mekong Delta and in Vietnam ...........................................................4
2.1. Political, Sociological and Economic Frame.....................................4
2.2. Water Sources and Supply ................................5
2.2.1 Groundwater Use in the Mekong Delta ...................................6
2.2.2 Surface Water Use in the Delta..6
2.2.3 Rain Water Use in the Mekong Delta......................................8
2.3. Sanitation, Waste and Waste Water Treatment..............................9
2.3.1 Sanitation ...........................................................................9
2.3.2 Solid Waste....................................... 11
2.3.3 Waste Water..................................... 12
2.4. Agriculture and Farming ............................................................ 13
2.4.1 Land Use and Farming Systems in the Mekong Delta............. 13
2.4.2 Natural Conditions............................................................. 15
2.4.3 Fertiliser Use..................................... 16
2.4.4 Expected Development....................................................... 17
2.5. Conclusions Regarding the Status Quo in the Mekong Delta and Expected Development ... 17
3. Required Systems ........................................................................................................18
3.1. Nutrient Demand in Agriculture.................. 18
3.2.Recycling Potential........................................................................................ 19
3.3. Water Treatment Systems.......................... 20
3.4. Demand for Wastewater Treatment Systems................................ 21
4. Anaerobic Treatment in Biogas Digesters....................................24
4.1. Background of Anaerobic Technology.......................................... 24
4.1.1 Process............................................. 24
4.1.2 Common Techniques and History......... 26
4.1.3 Development and Practice in Vietnam .................................. 29
4.1.4 Main Findings and Research Questions................................. 31
4.2. Material and Methods................................ 32
4.2.1 Field examinations............................. 32
4.2.1.1 Collaboration and Additional Data..................................... 32
4.2.1.2 Chemical and Microbiological Analysis Methods.................................................. 33
4.2.1.3 Statistical Evaluation....................................................... 33
4.3. Results and Discussion.............................. 34
4.3.1 Wastewater Characteristics................. 34
4.3.1.1 Waste Water Types........................................................ 34
4.3.1.2 Composition of Water Sources ......................................... 36
4.3.2 Management of Biogas Digesters and Process Parameters...................................... 37
IIIContent and Lists
4.3.2.1 Management.................................................................................................. 37
4.3.2.2 Hydraulic Retention Time................ 38
4.3.2.3 Loading Rate. 38
4.3.2.4 Process Parameters........................ 41
4.3.3 Wastewater Treatment Efficiency......................................................................... 43
4.3.3.1 Suspended Solids and Turbidity....... 43
4.3.3.2 Biological and Chemical Oxygen Demand .......................................................... 43
4.3.3.3 Microbiology .................................. 44
4.3.3.4 Summary and Recommendations for Process and Wastewater............................. 46
4.3.4 Balance and Fluxes............................ 48
4.3.4.1 Pig Sty Balance.............................. 48
4.3.4.2 Water Balance for Biogas Digesters .................................................................. 48
4.3.4.3 Nutrient Fluxes in ... 49
4.3.5 Potential Use as Fertiliser.................................................................................... 50
4.3.5.1 Effluent......................................... 50
4.3.5.2 Sludge.......... 55
4.3.6 Economic Aspects.............................. 56
4.3.6.1 Business Economics........................ 56
4.3.6.2 Further Effects and National Economics ............................................................ 57
4.4. Conclusions.............................................................................. 57
5. Waste Water Ponds......................................59
5.1. Introduction............. 59
5.1.1 Process................................................................ 59
5.1.2 History and Common Techniques......... 59
5.1.3 Practice in the Mekong Delta............................................... 60
5.1.4 Research Questions............................................................ 60
5.2. Material and Methods................................................................ 60
5.3. Results and Discussion.............................. 61
5.3.1 Field Parameters 61
5.3.2 Biological and Chemical Oxygen Demand 62
5.3.3 Microbiology...................................................................................................... 62
5.3.4 Nitrogen........... 63
5.3.5 Reuse of Pond Water and Sludge for Agriculture and Aquaculture ........................... 63
5.3.5.1 Reuse of Water.............................. 63
5.3.5.2of Pond Sludge..................................................................................... 64
5.4. Conclusions.............................................. 64
6. Composting of Biogas Sludge.......................65
6.1. Introduction............................................................................. 65
6.1.1 Process............................................. 65
6.1.2 History and Common Techniques......... 67
6.1.3 Development and Practice in Vietnam.. 70
6.1.4 Summary and Research Questions....................................................................... 72
6.2. Material and Methods................................ 72
6.2.1 Set-up.............. 72
6.2.3 Measurements... 73
6.3. Results and Discussion.............................................................. 74
6.3.1 Management and Process Parameters.................................. 74
6.3.1.1 Observations ................................. 74
6.3.1.2 Temperature.. 75
6.3.1.3 Moisture........................................ 76
6.3.1.4 Mass Balance. 77
6.3.2 Fertiliser Quality................................ 78
IVContent and Lists
6.3.2.1 Carbon and Nitrogen ...................................................................................... 78
6.3.2.2 Hygienic Parameters....................... 79
6.3.2.3 Heavy Metals................................. 81
6.3.2.4 Maturity and Plant Acceptance......................................... 82
6.3.2.5 Field Application............................................................. 84
6.4. Conclusions and Outlook............................................................ 85
6.4.1 General............................................. 85
6.4.2 Process and Experimental Set-up......................................... 85
6.4.3 Application and implementation in the Mekong Delta............. 86
7. Vermicomposting.........................................87
7.1. Introduction............................................................................. 87
7.1.1 Process 87
7.1.2 Common Techniques and History......... 89
7.1.3 Vermicomposting in Vietnam............................................... 90
7.1.4 Summary and Research Questions....................................... 90
7.2. Material and Methods ................................................................ 91
7.2.1 Set-up.............. 91
7.2.2 Measurements... 92
7.3. Results and Discussion.............................. 93
7.3.1 Management and Process Parameters .................................................................. 93
7.3.2 Mass Development............................................................. 94
7.3.3 Nutrients........... 96
7.3.4 Hazardous Substances........................ 99
7.3.4.1 Hygienic Parameters....................................................... 99
7.3.4.2 Anorganic Salts and Heavy Metals...........................