Characterisation of a high pH cement backfill for the geological disposal of nuclear waste: the Nirex Reference Vault Backfill

Rita G. W. Vasconcelos; Nicolas Beaudoin; Andrea Hamilton; Neil C. Hyatt; John L. Provis; Claire L. Corkhill

doi:10.1016/j.apgeochem.2017.11.007

Characterisation of a high pH cement backfill for the geological disposal of nuclear waste

the Nirex Reference Vault Backfill

Rita G. W. Vasconcelos, Nicolas Beaudoin, Andrea Hamilton, Neil C. Hyatt, John L. Provis, Claire L. Corkhill

Civil And Environmental Engineering

Research output: Contribution to journal › Article

8 Citations (Scopus)

26 Downloads (Pure)

Abstract

In a conceptual UK geological disposal facility for nuclear waste within a high-strength, crystalline geology, a cement-based backfill material, known as Nirex Reference Vault Backfill (NRVB), will be used to provide a chemical barrier to radionuclide release. The NRVB is required to have specific properties to fulfil the operational requirements of the geological disposal facility (GDF); these are dependent on the chemical and physical properties of the cement constituent materials and also on the water content. With the passage of time, the raw materials eventually used to synthesise the backfill may not be the same as those used to formulate it. As such, there is a requirement to understand how NRVB performance may be affected by a change in raw material supply. In this paper, we present a review of the current knowledge of NRVB and results from a detailed characterisation of this material, comparing the differences in performance of the final product when different raw materials are used. Results showed that minor differences in the particle size, surface area and chemical composition of the raw material had an effect on the workability, compressive strength, the rate of hydration and the porosity, which may influence some of the design functions of NRVB. This study outlines the requirement to fully characterise cement backfill raw materials prior to use in a geological disposal facility and supports ongoing assessment of long-term post-closure safety.

Original language	English
Pages (from-to)	180-189
Number of pages	10
Journal	Applied Geochemistry
Volume	89
Early online date	15 Nov 2017
DOIs	https://doi.org/10.1016/j.apgeochem.2017.11.007
Publication status	Published - 28 Feb 2018

Fingerprint

Radioactive Waste

backfill

Radioactive wastes

Waste disposal

radioactive waste

Raw materials

Cements

cement

Geology

Radioisotopes

Hydration

Chemical properties

Water content

Compressive strength

Physical properties

Porosity

Particle size

Crystalline materials

hydration

compressive strength

Keywords

geological disposal
nuclear waste
cement
mineralogy
microstructure

Cite this

Vasconcelos, R. G. W., Beaudoin, N., Hamilton, A., Hyatt, N. C., Provis, J. L., & Corkhill, C. L. (2018). Characterisation of a high pH cement backfill for the geological disposal of nuclear waste: the Nirex Reference Vault Backfill. Applied Geochemistry, 89, 180-189. https://doi.org/10.1016/j.apgeochem.2017.11.007

Vasconcelos, Rita G. W. ; Beaudoin, Nicolas ; Hamilton, Andrea ; Hyatt, Neil C. ; Provis, John L. ; Corkhill, Claire L. / Characterisation of a high pH cement backfill for the geological disposal of nuclear waste : the Nirex Reference Vault Backfill. In: Applied Geochemistry. 2018 ; Vol. 89. pp. 180-189.

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abstract = "In a conceptual UK geological disposal facility for nuclear waste within a high-strength, crystalline geology, a cement-based backfill material, known as Nirex Reference Vault Backfill (NRVB), will be used to provide a chemical barrier to radionuclide release. The NRVB is required to have specific properties to fulfil the operational requirements of the geological disposal facility (GDF); these are dependent on the chemical and physical properties of the cement constituent materials and also on the water content. With the passage of time, the raw materials eventually used to synthesise the backfill may not be the same as those used to formulate it. As such, there is a requirement to understand how NRVB performance may be affected by a change in raw material supply. In this paper, we present a review of the current knowledge of NRVB and results from a detailed characterisation of this material, comparing the differences in performance of the final product when different raw materials are used. Results showed that minor differences in the particle size, surface area and chemical composition of the raw material had an effect on the workability, compressive strength, the rate of hydration and the porosity, which may influence some of the design functions of NRVB. This study outlines the requirement to fully characterise cement backfill raw materials prior to use in a geological disposal facility and supports ongoing assessment of long-term post-closure safety.",

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Vasconcelos, RGW, Beaudoin, N , Hamilton, A, Hyatt, NC, Provis, JL & Corkhill, CL 2018, 'Characterisation of a high pH cement backfill for the geological disposal of nuclear waste: the Nirex Reference Vault Backfill', Applied Geochemistry, vol. 89, pp. 180-189. https://doi.org/10.1016/j.apgeochem.2017.11.007

Characterisation of a high pH cement backfill for the geological disposal of nuclear waste : the Nirex Reference Vault Backfill. / Vasconcelos, Rita G. W.; Beaudoin, Nicolas ; Hamilton, Andrea; Hyatt, Neil C.; Provis, John L.; Corkhill, Claire L.

In: Applied Geochemistry, Vol. 89, 28.02.2018, p. 180-189.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Characterisation of a high pH cement backfill for the geological disposal of nuclear waste

T2 - the Nirex Reference Vault Backfill

AU - Vasconcelos, Rita G. W.

AU - Beaudoin, Nicolas

AU - Hamilton, Andrea

AU - Hyatt, Neil C.

AU - Provis, John L.

AU - Corkhill, Claire L.

PY - 2018/2/28

Y1 - 2018/2/28

N2 - In a conceptual UK geological disposal facility for nuclear waste within a high-strength, crystalline geology, a cement-based backfill material, known as Nirex Reference Vault Backfill (NRVB), will be used to provide a chemical barrier to radionuclide release. The NRVB is required to have specific properties to fulfil the operational requirements of the geological disposal facility (GDF); these are dependent on the chemical and physical properties of the cement constituent materials and also on the water content. With the passage of time, the raw materials eventually used to synthesise the backfill may not be the same as those used to formulate it. As such, there is a requirement to understand how NRVB performance may be affected by a change in raw material supply. In this paper, we present a review of the current knowledge of NRVB and results from a detailed characterisation of this material, comparing the differences in performance of the final product when different raw materials are used. Results showed that minor differences in the particle size, surface area and chemical composition of the raw material had an effect on the workability, compressive strength, the rate of hydration and the porosity, which may influence some of the design functions of NRVB. This study outlines the requirement to fully characterise cement backfill raw materials prior to use in a geological disposal facility and supports ongoing assessment of long-term post-closure safety.

AB - In a conceptual UK geological disposal facility for nuclear waste within a high-strength, crystalline geology, a cement-based backfill material, known as Nirex Reference Vault Backfill (NRVB), will be used to provide a chemical barrier to radionuclide release. The NRVB is required to have specific properties to fulfil the operational requirements of the geological disposal facility (GDF); these are dependent on the chemical and physical properties of the cement constituent materials and also on the water content. With the passage of time, the raw materials eventually used to synthesise the backfill may not be the same as those used to formulate it. As such, there is a requirement to understand how NRVB performance may be affected by a change in raw material supply. In this paper, we present a review of the current knowledge of NRVB and results from a detailed characterisation of this material, comparing the differences in performance of the final product when different raw materials are used. Results showed that minor differences in the particle size, surface area and chemical composition of the raw material had an effect on the workability, compressive strength, the rate of hydration and the porosity, which may influence some of the design functions of NRVB. This study outlines the requirement to fully characterise cement backfill raw materials prior to use in a geological disposal facility and supports ongoing assessment of long-term post-closure safety.

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KW - nuclear waste

KW - cement

KW - mineralogy

KW - microstructure

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M3 - Article

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SP - 180

EP - 189