A three-dimensional model of radionuclide migration from a canister of spent nuclear fuel

Authors

  • A Pereira

DOI:

https://doi.org/10.1260/175095407781421630

Abstract

The development of a three-dimensional model of the near-field of ageological repository for spent nuclear fuel is described. The near-fieldcomprises a canister where the spent fuel is enclosed, a layer of bentoniteclay around the canister, a backfilled tunnel over the canister’s depositionhole and finally, the fractured rock adjacent to the bentonite and the tunnel.The main transport processes are diffusion, sorption, radioactive decayand groundwater flow. A mathematical model attempts to couple thewater flow to the mass transport. This model has been simplified to reduceits computational complexity. Our results are compared with the results ofa compartment model obtained from the literature. It is concluded from theagreement between our 3D model and the compartment model, that theresistance approach used in one-dimensional compartment models isrobust enough for use in models for probabilistic risk analysis of long-termperformance of a geological repository.The development of a three-dimensional model of the near-field of ageological repository for spent nuclear fuel is described. The near-fieldcomprises a canister where the spent fuel is enclosed, a layer of bentoniteclay around the canister, a backfilled tunnel over the canister’s depositionhole and finally, the fractured rock adjacent to the bentonite and the tunnel.The main transport processes are diffusion, sorption, radioactive decayand groundwater flow. A mathematical model attempts to couple thewater flow to the mass transport. This model has been simplified to reduceits computational complexity. Our results are compared with the results ofa compartment model obtained from the literature. It is concluded from theagreement between our 3D model and the compartment model, that theresistance approach used in one-dimensional compartment models isrobust enough for use in models for probabilistic risk analysis of long-termperformance of a geological repository.

References

Dverstorp B., Mendes B., Pereira A. and Sundström B. Data Reduction for Radionuclide Transport Codes used in Performance Assessments: an Example of Simplification Errors. Mat. Res. Symp. Proc. Vol. 506, Materials Research Society, 1998. https://doi.org/10.1557/proc-506-797

Hedin, A. (2002). Integrated Analytic Radionuclide Transport Model for a Spent Nuclear Fuel Repository in Saturated Fractured Rock. Nuclear Technology 138, pp79-205. https://doi.org/10.13182/nt02-a3287

Neretnieks I. Stationary Transport of Dissolved Species in the Backfill Surrounding a Waste Canister in Fissured Rock: Some Simple Analytical Solutions. Nuclear Technol., 72, 196, 1986. https://doi.org/10.13182/nt86-a33741

Lindgren M and Lindström F. (1999). SR97 Radionuclide Transport Calculations. SKB report TR-99-23.

Pereira, A. (2006). Three Dimensional Modelling of a KBS-3 Canister for Spent Nuclear Fuel - some migration studies. SKI Report 2006:17, Stockholm, Sweden, in press.

Published

2007-06-30

How to Cite

Pereira, A. (2007) “A three-dimensional model of radionuclide migration from a canister of spent nuclear fuel”, The International Journal of Multiphysics, 1(2), pp. 189-198. doi: 10.1260/175095407781421630.

Issue

Section

Articles