Coupled transport/reaction modelling of copper canister corrosion aided by microbial processes

SummaryCopper canister corrosion is an important issue in the concept of a nuclear fuel repository. Previous studies indicate that the oxygen-free copper canister could hold its integrity for more than 100000 years in the repository environment.Microbial processes may reduce sulphate to sulphide and considerably increase the amount of sulphide available for corrosion. In this paper, a coupled transport/reaction model is developed to account for the transport of chemical species produced by microbial processes. The corroding agents like sulphide would come not only from the intruding groundwater, but also from the reduction of sulphate near the canister. The reaction of sulphate-reducing bacteria and the transport of sulphide in the bentonite buffer is included in the model. The local depth of copper canister corrosion is calculated by the model.

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Lifetimes of Used Nuclear Fuel Containers Affected by Sulphate-Reducing Bacteria Reactions inside the Canadian Deep Geological Repository

Applied Sciences ◽

10.3390/app11177806 ◽

2021 ◽

Vol 11 (17) ◽

pp. 7806

Author(s):

Jorge A. Garcia-Hernandez ◽

Kumaraswamy Ponnambalam ◽

Mythreyi Sivaraman

Keyword(s):

Nuclear Fuel ◽

Host Rock ◽

Bentonite Clay ◽

Reaction Diffusion ◽

Deep Geological Repository ◽

Sulphate Reducing Bacteria ◽

Used Nuclear Fuel ◽

Geological Repository ◽

Sulphide Production ◽

Reducing Bacteria

The present work aims at approximating the reduction of sulphate to sulphide caused by sulphate-reducing bacteria (SRB) inside the Canadian deep geological repository in order to calculate the expected lifetime of used nuclear fuel containers (UFCs). Previous studies have assumed a conservative constant concentration of sulphide at the host rock interface. The novelty of this study resides in the use of first-order kinetics to explicitly account for the SRB-induced sulphide production. This reaction term is developed following an empirical approach using published results on actual sulphate reduction by SRB and included in a coupled reaction-diffusion system. Lifetimes of UFCs are subsequently calculated following the conditions of two scenarios: having SRB active only at the region closest to the host rock and having SRB active at the host rock and throughout the bentonite clay. This study shows that the mean lifetimes of UFCs in both cases are above one million years. However, more accurate results would require the characterization of the host rock and groundwater of the prospective emplacement, as well as additional experiments on growth and sulphide production by the microbial communities from the site.

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A DFT Based Coupled Transport-Reaction Model for H2 Fueled SOFC Model Anodes

ECS Meeting Abstracts ◽

10.1149/ma2011-01/41/1890 ◽

2011 ◽

Keyword(s):

Reaction Model ◽

Coupled Transport ◽

Transport Reaction

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Investigation into Mechanisms of Microbial Effects on Iron and Manganese Transformations in Artificially Recharged Groundwater

Water Science & Technology ◽

10.2166/wst.1988.0080 ◽

1988 ◽

Vol 20 (3) ◽

pp. 47-53 ◽

Cited By ~ 1

Author(s):

Yan Bao-rui

Keyword(s):

Groundwater Quality ◽

Biochemical Reaction ◽

Reaction Products ◽

Injection Wells ◽

Iron Bacteria ◽

Sulphate Reducing Bacteria ◽

Prevention And Treatment ◽

Reducing Bacteria ◽

Iron And Manganese ◽

Microbial Effects

After artificial recharging of groundwater some problems occurred, such as changes in groundwater quality, the silting up of recharge (injection) wells, etc. Therefore, the mechanisms of microbial effects on groundwater quality after artificial recharging were studied in Shanghai and the district of Changzhou. These problems were approached on the basis of the amounts of biochemical reaction products generated by the metabolism of iron bacteria, sulphate-reducing bacteria, Thiobacillusthioparus, and Thiobacillusdenitrificans. The experiments showed that in the transformations occurring and the siltation of recharge wells, microorganisms play an important role, due to the various chemical and biochemical activities. A water-rock-microorganisms system is proposed, and some methods for the prevention and treatment of these effects are given.

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