Abstract
The objective of the current study was to evaluate the effects of supplementary pulverised fuel ash on phosphate-modified calcium aluminate cement. These systems are being established as part of a wider project to develop alternative cementing systems for the encapsulation of problematic low- and intermediate-level radioactive waste in the UK.
The nuclear industry has established specific processing and property criteria, which must be fulfilled to ensure suitability for industrial application. In a series of studies, pulverised fuel ash was used as a partial replacement for calcium aluminate cement to improve the fluidity of the system and increase the setting time. Properties such as slurry pH and fluidity, setting time, mechanical properties, and porosity were investigated using Vicat, Colflow, and compressive strength testing equipment and mercury intrusion porosimetry. The hardened cement pastes were also characterised using X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy.
A formulation envelope was identified, which fulfilled the plant acceptance tests defined by industry to ensure suitability for industrial application. It was found that pH of calcium aluminate phosphate cements is lower than that of conventional cementing systems used to encapsulate radioactive waste in the UK. Hence, they have potential to be used as an alternative cementing system for the encapsulation of problematic radioactive metals.
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Notes
- 1.
Water that is not chemically bound within the cement matrix, and is therefore available to react.
- 2.
Cement chemistry nomenclature; C = CaO, A = Al2O3, S = SiO2, T = TiO2, H = H2O.
References
Glasser FP (1992) Progress in the immobilization of radioactive wastes in cement. Cement Concr Res 22:201–216
Wilding CR (1992) The performance of cement based systems. Cement Concr Res 22(2–3):299–310
Setiadi A et al (2006) Corrosion of aluminium and magnesium in BFS composite cements. Adv Appl Ceram 105:191–196
Milestone NB et al (2006) Reactions in cemented nuclear waste forms – the need for a toolbox of different cement types. In: Materials Research Society symposium proceedings, vol 932
The 2007 UK Radioactive Waste Inventory (2007) Department for Environment, Food and Rural Affairs and Nuclear Decommissioning Authority, pp 1–140
Sugama T, Allan M, Hill JM (1992) Calcium phosphate cements prepared by acid-base reaction. J Am Ceram Soc 75(8):2076–2087
Sugama T, Carciello NR (1991) Strength development in phosphate-bonded calcium aluminate cements. J Am Ceram Soc 74(5):1023–1030
Sugama T, Carciello NR (1995) Sodium phosphate-derived calcium phosphate cements. Cement Concr Res 25(1):91–101
Setiadi A (2006) Corrosion of metals in composite cement. In: Department of Engineering Materials, The University of Sheffield, Sheffield
Swift P, Kinoshita H, Collier NC, Utton CA (2012) Phosphate modified calcium aluminate cement for radioactive waste encapsulation. Advances in Applied Ceramics
Sharp JH et al (2003) Cementitious systems for encapsulation of intermediate level waste. In: Proceedings of ICEM ‘03: the 9th international conference on radioactive waste management and environmental remediation, Oxford, England
Scrivener KL, Campas A (2006) Calcium aluminate cements, Chapter 13. In: Hewlett PC (ed) Lea’s chemistry of cement and concrete. Butterworth-Heinemann, Oxford, pp 711–782
Sugama T, Carciello NR, Gray G (1992) Alkali carbonation of calcium aluminate cements: influence of set-retarding admixtures under hydrothermal conditions. J Mater Sci 27(18):4909–4916
Methods of testing cement (2005) Determination of setting times and soundness, BS EN 196-3:2005+A1:2008, The British Standards Institution
Atkins M, Glasser FP (1992) Application of Portland cement-based materials to radioactive waste immobilization. Waste Manage 12(2–3):105–131
Megat Johari MA et al (2011)Influence of supplementary cementitious materials on engineering properties of high strength concrete. Construct Build Mater 25(5):2639–2648
Lee SH et al (2003) Effect of particle size distribution of fly ash-cement system on the fluidity of cement pastes. Cement Concr Res 33(5):763–768
Chatterjee AK (2002) Special cements, Chapter 6. In: Bensted J, Barnes P (eds) Structures and performance of cements. Spon Press, London
Majumdar AJ, Edmonds RN, Singh B (1990) Hydration of Secar 71 aluminous cement in presence of granulated blast furnace slag. Cement Concr Res 20(1):7–14
Bensted J (2002) Calcium aluminate cements, Chapter 4. In: Bensted J, Barnes P (eds) Structure and performance of cements. Spon Press, London
Acknowledgments
Thanks are given to the Immobilisation Science Laboratory (ISL) of the University of Sheffield. Special thanks are given to Dr. Claire Utton of the ISL, Dr. Martin Hayes of the National Nuclear Laboratory (NNL), and Dr. Neil Milestone of Milestone and Associates Ltd., New Zealand for their helpful discussions and support. The authors gratefully acknowledge the Engineering and Physical Sciences Research Council and NNL for funding.
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Swift, P., Kinoshita, H., Collier, N.C. (2013). The Effect of Supplementary Pulverised Fuel Ash on Calcium Aluminate Phosphate Cement for Intermediate-Level Waste Encapsulation. In: Bart, F., Cau-di-Coumes, C., Frizon, F., Lorente, S. (eds) Cement-Based Materials for Nuclear Waste Storage. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-3445-0_19
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