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Development and Utilisation of Bayer Process By-Products

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Development and Utilisation of Bayer Process By-Products School of Civil and Mechanical Engineering Department of Civil Engineering Development and Utilisation of Bayer process By-products Evan John Jamieson This thesis is presented for the Degree of Doctor of Philosophy of Curtin University October 2013 DECLARATION To the best of my knowledge and belief this thesis contains no material previously published by any other person except where due acknowledgement has been made. This thesis contains no material which has been accepted for any other degree or diploma in any University. Evan John Jamieson October, 2013 ii ABSTRACT The Bayer Process is the hydrometallurgical treatment of bauxite ore for the extraction of alumina. Globally this process produces in excess of 64 millions of tonnes per annum of alumina (IAI, 2011). This extraction also results in a non- extracted residue called red mud. CSIRO (2011) report an estimated 120 million tonnes per annum of red mud production. This product is typically highly alkaline and needs to be contained in long-term secure storage facilities. It could however, be considered an underutilised resource. Karl Bayer’s original patent outlined many possible uses for bauxite residue (Bayer, 1889) and research has been conducted towards that outcome almost continuously since. In that time, very few products have entered the market and most are only of small volume. This thesis assesses a variety of possible Bayer process by-products, and their subsequent utilisation. The focus is upon production of high volume commodity products that are made to specification and are suitable for multiple applications. This work includes pilot plant production and field demonstration trials. This thesis reports on four key products that could make significant impact upon utilisation of wasted resources. These products are, • Carbonated Red Mud and Alkaloam® - produced from the fine bauxite residue commonly termed red mud; • Red Sand™ - manufactured from coarse bauxite residue; • Red Lime™ - a by-product of liquor causticisation; • Bayer-derived geopolymers - a cement replacement made from processed Bayer liquor. These four products have been assessed and demonstrate significant benefit in their potential use. iii ACKNOWLEDGEMENTS I would like to sincerely thank my supervisors, Professor Hamid Nikraz (Principal, Curtin University) for his support and guidance throughout this project and David White (Associate, Alcoa of Australia Limited “Alcoa”), for his direction and review. Their support has allowed this thesis to be an enjoyable process. Special thanks to Associate Professor Arie Van Riessen, Dr Robert Hart, Dr Catherine Kealley, Dr William Rickard, Emily Carter, Felicia Lee, Min (Emily) Xie, Barry Wittington, Bruno Penna and Les Vickers of the Centre for Materials Research, Curtin University. Their technical expertise in the field of geopolymer science has ensured the smooth progress of development. Thanks to Gary Johnson, Gary Jones, Sarvesh Mali and Jeremy Robertson of Boral Technical Services, for assistance with larger mix demonstrations and assessment of Bayer aggregate testing within Ordinary Portland Cement (OPC) concrete. Thanks to Mark Whittaker and Alireza Rezagholilou for access to the Curtin Civil Engineering laboratory equipment and for teaching me how to interpret the data. Thanks to Diane Garth for keeping the university student paperwork in check. Thanks to Jacquie Greene and Sarah Daw for assistance with Alcoa documentation. Thanks to Dr Shelly Attiwell for her invaluable assistance and training in the interpretation of ASLP, TCLP and pH dependence leach testing. Thanks to Bureau Veritas (Ultra Trace) and Intertek (Genalysis) for processing samples in a timely fashion. Thanks to Alan Jones for being a mate as well as a colleague. Apart from keeping me out of trouble while in the field, he has proven to be highly resourceful. Thanks for the reality checks. Thanks to Associate Professor Norman Stockton, formerly of West Australian School of Mines, for his help with understanding and application of separation technologies. iv Thanks to Dr Stevan Green and Dr Mark Neville formerly of the Cooperative Research Centre - Centre for Sustainable Resource Processing (CSRP), where the ideas for maximisation of public benefit were nurtured. Thanks to Dr Glen Corder of the Sustainable Minerals Institute (SMI) and Dr Ben McLellan of the School of Energy Science, Kyoto University for assistance with evaluation of sustainability of by-products, particularly Red Sand(TM) and geopolymer respectively. Thanks to Dr Robert Summers, Dr Mark Rivers, Martin Clarke, Adam Lillicrap and the crew from the Department of Agriculture and Food, Western Australia (DAFWA). Their long term independent monitoring of Red SandTM, Red LimeTM and Alkaloam(R) trials were critical to product validation. Thanks to Tom Bond of WML Consultants and Bahaa Kanbour of Main Roads Western Australia (MRWA) for the opportunity to conduct trials and their independent assessment of Red SandTM in road construction. Thanks to the crew of Southern Road Services for their tolerance of my presence during road construction. Thanks to Mark Drechsler of Parsons Brinkerhoff Australia Pty Ltd for assessment of sand reshaping technologies. Thanks to the Fairbridge Village Board for the opportunity to conduct a demonstration field trial on lawn top dressing. Also to Dave Allen of MBS Environmental Pty Ltd for environmental assessment of the site and to Ecotech Pty Ltd for air monitoring. Thanks to Kathy Allen for the corporate library services. Where would we be without the smooth flow of information? Also to Kit Farrelly of Curtin University of Technology, who provided similar services for the non-corporate related topics. Thanks to Stephen Leavy and the Analytical Services Group within Alcoa’s Technology Delivery Group, for their tireless performance and pursuit of accuracy. v A special mention to Margaret McIntyre, Anne Donovan, Lydia Formentin, Renscha Van Niekerk, Helen Coleman, David del Pino and Kim-Louise Burke. Thanks to Karen Lambeck, Daniel Ward and Shannon Dye for help with commercial and intellectual property issues. Thanks to Albert Russo for his assistance in the field of Bayer Liquor analysis, Kevin Beckham for improving the automated geopolymer formulations model and Sharon Eyer for assistance with XRF, XRD and SEM. My appreciation also goes to Kirk Moore for the determination of the Bayer evaporation energy consumption. I wish to acknowledge the assistance of Dr Shelly Attiwell again and the expertise of Professor Brian O’Conner for assistance in the field of radiological analysis, calculation and comparison to regulations. Thanks also to Peter Swash and John Cornell for assistance with QEMSCAN mineralogical assessment of Red Sand™ grains. I am grateful to Alcoa of Australia Limited, particularly to Dr Ian Harrison, Dr Chris Baker, and Dr Anthony McKinnon for allowing me the opportunity to publish this thesis. It highlights the progressive nature of the organisation to support this aspiration and the respect afforded to me by my managers. Many thanks. I wish to thank my mother (Dorothy) for her support and I acknowledge the encouragement of my late father (Alexander). Thanks also to Bob and Val (Dad and Mum 2). Thanks to my beloved children, Katelyn and Suzanne, for occasionally allowing me to have use of the computer. Finally, I thank my wife Barbara Ann, for always being by my side; a wife of distinction, a lady of honour and a friend of God. To God be glory. 1 Peter 4:11 "If anyone ministers, let him do it as with the ability that God supplies, that in all things God may be glorified through Jesus Christ, to whom belong the glory and the dominion forever and ever." NKJV. vi DEDICATION To those that suffer from the hidden disease of the black dog: I say never ever give up. You can survive it. The dog lies. Get help. Please! I have commenced and completed this thesis while suffering the mental illness of anxiety and depression. I performed this task to show to my children and others that mental illness is an “Illness”. It is not a lack of cognitive function or rational thought. vii LIST OF PUBLICATIONS ARISING FROM WORK Refereed Journals Van Riessen, A., Jamieson, E., Kealley, C., Hart, R., & Williams, R. (2013). Bayer- Geopolymers: An exploration of synergy between the alumina and geopolymer industries. Cement and Concrete Composites. 41. pp. 29–33. Journal Impact Factor = 2.421. Kealley, C., Van Riessen, C., Jamieson, E., & Hart, R. (2013). Optimisation of ambient setting flyash – Bayer liquor geopolymers. Submitted to Cement and Concrete Composites, 2013. Journal Impact Factor = 2.421. Jamieson, E., McLellan, B., Van Riessen, A., & Nikraz, H. (2013). Embodied energy of Bayer-derived geopolymers. Submitted to Journal of Cleaner Production. Journal Impact Factor = 3.398. Jamieson, E., Van Riessen, A., Kealley, C., & Hart, R., (2014). Development and use of Bayer geopolymer concrete. To be submitted to Hydrometallurgy 2014. Journal Impact Factor = 2.027 Attiwell, S., Jamieson, E., Van der Sloot, H., & Nikraz, H. (2014). Nitrate leach investigation of ameliorated soils using standard and a modified pH dependence test. In final preparation Attiwell, S., Jamieson, E., Van der Sloot, H., & Nikraz, H. (2014). Comparative assessment of the Australian and European Standard Leach tests for assessment of industrial by-products for re-use. In final preparation viii Refereed Conferences Jamieson, E., Van Riessen, A., Kealley, C., & Hart, R. (2012). Development of Bayer geopolymer paste and use as concrete.
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