1st Edition

Adsorptive Removal of Manganese, Arsenic and Iron from Groundwater UNESCO-IHE PhD Thesis

By Richard Buamah Copyright 2010
    198 Pages
    by CRC Press

    198 Pages
    by CRC Press

    Arsenic, manganese and iron in drinking water at concentrations exceeding recommended guideline values pose health risks and aesthetic defects. Batch and pilot experiments on manganese adsorption equilibrium and kinetics using iron-oxide coated sand (IOCS), Aquamandix and other media have been investigated and modeled. Effect of manganese and iron loading on manganese removal and rate of oxidation of adsorbed iron and manganese have been studied.

    Aquamandix and IOCS demonstrated iron and manganese adsorption capacity that increases with increasing pH under oxic and anoxic conditions. Manganese loading and low filtration rate using feedwater with no nitrite favour non-uniform development of catalytic manganese oxide on media that subsequently enhances manganese removal.

    Acknowledgements                                                   
    Abstract                                                            

    1 Introduction                                                    
    1.1 Water consumption, resources and quality                        
    1.1.1 Groundwater use and quality in Ghana                   
    1.1.2 Groundwater use and quality in the Netherlands            
    1.1.3 Groundwater quality problems                         
    1.2 Manganese, arsenic and iron removal methods                     
    1.3 Origin, mobilization and chemistry of manganese, arsenic and iron    
    1.3.1 Manganese in groundwater: reduction and oxidation         
    1.3.2 Arsenic in groundwater                               
    1.3.3 Iron in groundwater: reduction and oxidation              
    1.4 Theoretical background of adsorptive processes                    
    1.4.1 Equilibra                                           
    1.4.2 Forces and energetics of adsorption                     
    1.4.3 Adsorbate – solvent properties                         
    1.4.4 Adsorption isotherm                                 
    1.5 Need for research                                           
    1.6 Research objectives                                          
    1.7 Outline of the thesis                                         
    1.8 References                                                 

    2 Presence of manganese, iron and arsenic in the groundwater within the gold-belt zone of Ghana                                       
    2.1 Introduction                                                
    2.1.1 Sources of manganese, iron and arsenic in groundwater      
    2.1.2 Simplified geology of Ghana                           
    2.1.3 The gold belts of Ghana                              
    2.2 Materials and methods                                       
    2.2.1 Communities within regions and districts covered           
    2.2.2 Analysis of samples                                  
    2.3 Results and discussions                                       
    2.3.1 Categorization of wells                                
    2.3.2 Occurrence of manganese and iron                      
    2.3.3 Occurrence of arsenic.                                
    2.3.4 Arsenic contamination, mobilization and geology          
    2.4 Conclusions                                                
    2.5 References                                                 

    3 Adsorptive removal of manganese (II) from the aqueous phase using iron oxide coated sand                                           
    3.1 Introduction                                                
    3.2 Theoretical background                                       
    3.2.1 Solubility and oxidation states of manganese               
    3.2.2 The adsorption phenomenon                           
    3.2.3 Freundlich’s adsorption isotherm                       
    3.2.4 Adsorption kinetic models                             
    3.3 Materials and methods                                       
    3.3.1 Materials for batch studies                             
    3.4 Results and discussions                                       
    3.4.1 The effect of pH and hydrogen carbonate                 
    3.4.2 Adsorption isotherms                                 
    3.4.3 Adsorption kinetic study                               
    3.5 Conclusion                                                
    3.6 References                                                 

    4 Manganese adsorption characteristics of selected filter media for groundwater treatment: equilibrium and kinetics                     
    4.1 Introduction                                                
    4.2 Theoretical background                                       
    4.2.1 Oxidation of manganese                               
    4.2.2 Isotherms of manganese adsorption on media              
    4.2.3 Kinetics of manganese adsorption                       
    4.3 Experimental section                                         
    4.3.1 Materials                                           
    4.3.2 Methodology                                       
    4.4 Results and discussion                                        
    4.4.1 Adsorption isotherms                                 
    4.4.2 Manganese removal under oxic and anoxic condition        
    4.4.3 Adsorption kinetics                                   
    4.4.4 Relationship between the manganese adsorption potential and the media characteristics                               
    4.5 Conclusion                                                
    4.6 References                                                 
    Appendix 4.1                                               

    5 Manganese removal from groundwater; problems in practice and potential solutions                                               
    5.1 Introduction                                                
    5.2 Theoretical background                                       
    5.3 Materials and methods                                       
    5.3.1 Pilot plant experiments                                
    5.3.2 Laboratory and bench scale investigations                 
    5.3.3 Development coating and Scanning Electron Microscopy investigations                                       
    5.4 Results and discussions                                       
    5.4.1 Pilot plant experiments                                
    5.4.2 Laboratory and bench scale investigations                 
    5.4.3 Development coating and Scanning Electron Microscopy investigations                                       
    5.5 Conclusions                                                
    5.6 Acknowledgement                                          
    5.7 References                                                 

    6 Optimising the removal of manganese in UNESCO-IHE arsenic removal family filter treating groundwater with high arsenic, manganese, ammonium and iron                                   
    6.1 Introduction                                                
    6.2 Theoretical background                                       
    6.2.1 The role of metallic oxides in arsenic removal              
    6.2.2 Influence of ammonium and methane on manganese, arsenic and iron removal                              
    6.3 Family filter for arsenic removal                                
    6.4 Methodology, equipment and materials                          
    6.4.1 Column experiment                                  
    6.5 Result and discussions                                        
    6.5.1 Column experiments.                                 
    6.6 Conclusions                                                
    6.7 References                                                 
    Appendix 6.1                                               

    7 Oxidation of adsorbed ferrous and manganese ions: kinetics and influence of process conditions                                            
    7.1 Introduction                                                
    7.2 Theoretical background for kinetics                             
    7.3 Material and methods                                        
    7.3.1 Preliminary tests                                     
    7.3.2 Experimental set up                                  
    7.4 Results and discussions                                       
    7.4.1 Characterization of the IOCS media                      
    7.4.2 Residence time distribution                            
    7.4.3 Column experiments – adsorbed ferrous oxidation          
    7.4.4 Column experiment – adsorbed Mn2+ oxidation with Aquamandix                                       
    7.5 Conclusions                                                
    7.6 References                                                 
    Appendix 7.1                                               

    8 Summary and conclusions                                        
    8.1 Introduction                                                
    8.1.1 Groundwater quality                                  
    8.1.2 Groundwater treatment                                
    8.1.3 Need for research and objectives
    8.2 Presence of manganese, iron and arsenic in the groundwater         
    8.3 Adsorptive removal of manganese(II) from the aqueous phase using IOCS                                                
    8.4 Manganese adsorption characteristics of selected filter media for groundwater treatment: equilibria and kinetics                     
    8.5 Manganese removal from groundwater; problems in practice and potential solution                                            
    8.6 Optimising the removal of manganese in UNESCO-IHE arsenic removal family filter treating groundwater with high arsenic, manganese, ammonium and iron                                
    8.7 Oxidation of adsorbed ferrous and manganese ions: kinetics and influence of process conditions                                 
    8.8 Reference                                                 
    8.9 Recommendations for further studies                            

    Samenvatting (Summary in Dutch)                                       
    List of symbols                                                      
    Abbreviations                                                       
    List of Publications and Presentations                                     
    Curriculum Vitae                                                     

    Biography

    Richard Buamah (1966) is born in Ghana. He completed Bachelor of Science degree in Biochemistry at the Kwame Nkrumah University of Science and Technology (KNUST) in 1990. Five years later he completed his Master of philosophy degree programme in Biochemistry at KNUST. In 2000 he joined the UNESCO-IHE Institute for Water Education (the Urban Water and Infracture department) to pursue a number of graduate courses in Water Treatment followed by a PhD programme under sandwich construction.
    He has twelve publications to his credit and has presented papers and posters at several peer reviewed conferences including the Biennial World Water Congress of the IWA (2008, Vienna, Austria), the Leading Edge Technology Conference of the IWA (2008 Zurich, Switzerland) and UCOWR/NIWR conference, (2009, Durham, North Carolina – USA).