Treatment of Municipal Wastewater Reverse Osmosis Concentrate using Biological Activated Carbon based Processes A thesis submitted in fulfilment of the requirement for the degree of Doctor of Philosophy (PhD) Shovana Pradhan Master of Engineering (Civil/Environmental), Asian Institute of Technology (AIT), Thailand School of Civil, Environmental and Chemical Engineering College of Science, Engineering and Health RMIT University, Melbourne, Australia November, 2016 Declaration I hereby declare that: • the work presented in this thesis is my own work except where due acknowledgement has been made; • the work has not been submitted previously, in whole or in part, to qualify for any other academic award; • the content of the thesis is the result of work which has been carried out since the official commencement date of the approved research program. .............................. (Shovana Pradhan) ........../........../.......... 1 Acknowledgements I would like to express my sincere thanks and deep gratitude to my senior supervisor, Dr. Linhua Fan who has kindly given me the opportunity to pursue PhD study under his constant guidance. This thesis would have not been possible without his continuous encouragement, constructive feedback, invaluable advice and scientific inputs. Secondly, I would like to thank Prof. Felicity Roddick as my second supervisor, for her generous support, insightful counsel throughout my study period. She has been extremely motivating, encouraging and positive to my research work. The timely and constructive feedback from my supervisors helped me to improve the quality of my work, as well as professional development during my PhD work. I am grateful for providing scholarship to pursue my PhD by RMIT University. I would like to thank Prof. Andrew S. Ball from the School of Science for providing continuous and generous support to accomplish the microbiological study for my work. I am grateful to Dr. Esmaeil Shahsavari for his kind instructions and guidance for microbiological study, and outstanding help during PCR-DGGE-sequencing experiments. I would also like to thank the laboratory staffs: Dr. Sandro Longano, Mr. Cameron Crombie and Mrs. Peggy Chang for their continuous support and assistance with various technical instruments and chemicals throughout my research in Chemical Engineering Department. I am grateful to Dr. Thang Nguyen for his invaluable suggestion and continuous encouragement. Heartfelt thanks to my fellow colleagues and former postgraduate students: Dr. Muhammad Umar, Dr. Xiaolei Zhang and Dr. Biplob Kumar Pramanik, whose companionship and fruitful discussions have helped to create a stimulating and fun environment to learn and grow. Time spent with my colleagues will always cherish my memory. I wish to express my deepest gratitude to my parents, Lal Chand Pradhan and Saraswoti Pradhan, to whom this thesis is dedicated. This thesis would certainly not have existed without you and your support, encouragement, unconditional love and unending sacrifice. To my husband, Raju Sitoula, thank you for sharing this journey. This thesis is the outcome of your continuous and indispensable support throughout my research. I am indebted to your love and care, and taking utmost care of our daughters (Sarakshi Sitoula and Samyuka Sitoula) during my research. I am forever grateful to you all. Love you all. 2 List of publications Peer-refereed journal papers 1. Shovana Pradhan , Linhua Fan, Felicity A. Roddick, Esmaeil Shahsavari, Andrew S. Ball (2016). Impact of salinity on organic matter and nitrogen removal from a municipal wastewater RO concentrate using biologically activated carbon coupled with UV/H 2O2. Water Research, 94, 103-110. 2. Shovana Pradhan , Linhua Fan, Felicity A. Roddick (2015). Removing organic and nitrogen content from a highly saline municipal wastewater reverse osmosis concentrate by UV/H 2O2-BAC treatment. Chemosphere, 136, 198-203. 3. Shovana Pradhan , Linhua Fan, Felicity A. Roddick, Esmaeil Shahsavari, Andrew S. Ball. Treatment of a reverse osmosis concentrate using BAC-UV/H 2O2 in the reclamation of a municipal wastewater containing a significant proportion of petrochemical process wastewater. Under preparation. 4. Shovana Pradhan , Linhua Fan, Felicity A. Roddick. A comparative study of organic matter and nutrient removal by BAC-based processes on two RO concentrate streams with significantly different characteristics. Under preparation. Peer-reviewed conference papers 1. Shovana Pradhan, Linhua Fan and Felicity A. Roddick, 2015. Biological activated Carbon treatment of a highly saline reverse osmosis concentrate from municipal wastewater reclamation, International Desalination Association World Congress on Desalination and Water Reuse, August 30-September 4, 2015, San Diego, USA. 2. Shovana Pradhan, Linhua Fan and Felicity A. Roddick, 2014 . Treating municipal wastewater RO concentrate by a UV/H 2O2-BAC process for safe disposal, Qingdao International Conference on Desalination and Water Reuse, 9-12 June 2014, Qingdao, China. 3 3. L. Fan, J. Lu, S. Pradhan, F.A. Roddick, 2013. Reducing environmental risk of municipal wastewater reverse osmosis concentrate by an AOP-BAC treatment, International Desalination Association World Congress on Desalination and Water Reuse, 20-25 October 2013, Tianjin, China. Conference poster 1. Felicity Roddick, Thang Nguyen, Muhammad Umar, Shovana Pradhan and Linhua Fan, 2015. Process comparison for the treatment of a municipal wastewater reverse osmosis concentrate, Ozwater 15 Conference, 12-14 May, Adelaide, Australia. 4 Table of Contents Declaration ................................................................................................................................ 1 Acknowledgements ................................................................................................................... 2 List of publications ................................................................................................................... 3 Table of Contents ...................................................................................................................... 5 List of Figures ........................................................................................................................... 9 List of Tables ........................................................................................................................... 11 Nomenclature .......................................................................................................................... 13 List of abbreviations ............................................................................................................... 14 Summary ................................................................................................................................. 17 Introduction ................................................................................................... 21 1.1 Aim of the study and research questions: .................................................................. 26 1.2 Thesis Structure ......................................................................................................... 27 Literature Review ......................................................................................... 29 2.1 Introduction ................................................................................................................ 29 2.2 ROC disposal options ................................................................................................ 30 2.3 Characteristics of ROC, contaminants and potential environmental impacts ............ 33 2.4 Treatment of municipal ROC .................................................................................... 37 2.4.1 Physico-chemical treatment of municipal wastewater ROC ..................................... 37 2.4.2 Advanced Oxidation Processes (AOPs) .................................................................... 39 2.5 Biological processes .................................................................................................. 49 2.6 Biological activated carbon (BAC) ............................................................................ 50 2.6.1 Integrated treatment option for ROC using BAC ...................................................... 53 2.6.2 Nutrient removal during AOP and BAC processes ................................................... 57 2.7 Microbiological study of BAC systems ..................................................................... 61 2.8 Summary of Literature review ................................................................................... 62 Materials and Methods ................................................................................. 65 3.1 Analytical Methods .................................................................................................... 65 3.1.1 Dissolved organic carbon ........................................................................................... 65 3.1.2 Colour ........................................................................................................................ 65 3.1.3 Ultraviolet Absorbance (UVA 254 ) .............................................................................. 65 3.1.4 Specific UV absorbance (SUVA) .............................................................................. 66 3.1.5 Alkalinity and chloride .............................................................................................. 66 5 3.1.6