TY - GEN
T1 - Identification of Oxygen-Depleting Components in MX-80 Bentonite
AU - Carlsson, Torbjörn
AU - Muurinen, Arto
PY - 2009
Y1 - 2009
N2 - After closure, the near-field of a nuclear waste
repository contains large amounts of oxygen in tunnels
and deposition holes. The bentonite buffer/backfill will
contain oxygen as a gas phase in unsaturated pores as
well as dissolved gas in porewater. The redox conditions
in the bentonite filling after post-closure will change
towards reducing conditions. In the initial stage, the
development of the redox state is mainly governed by the
depletion of oxygen. The main mechanisms of oxygen
depletion in the bentonite are: 1) diffusion into the
surrounding rock and 2) reactions with accessory minerals
and by microbial aerobic consumption of organic matter
[1,2]. The reactions leading to oxygen depletion are not,
however, well understood. The objective of this work was
to gather new information concerning oxygen depletion in
MX-80. This was done by measuring oxygen depletion and
changes in the redox state in suspensions of 1) MX-80, 2)
a heavy fraction of MX-80, or 3) a light fraction of
MX-80.
AB - After closure, the near-field of a nuclear waste
repository contains large amounts of oxygen in tunnels
and deposition holes. The bentonite buffer/backfill will
contain oxygen as a gas phase in unsaturated pores as
well as dissolved gas in porewater. The redox conditions
in the bentonite filling after post-closure will change
towards reducing conditions. In the initial stage, the
development of the redox state is mainly governed by the
depletion of oxygen. The main mechanisms of oxygen
depletion in the bentonite are: 1) diffusion into the
surrounding rock and 2) reactions with accessory minerals
and by microbial aerobic consumption of organic matter
[1,2]. The reactions leading to oxygen depletion are not,
however, well understood. The objective of this work was
to gather new information concerning oxygen depletion in
MX-80. This was done by measuring oxygen depletion and
changes in the redox state in suspensions of 1) MX-80, 2)
a heavy fraction of MX-80, or 3) a light fraction of
MX-80.
U2 - 10.1557/PROC-1124-Q05-02
DO - 10.1557/PROC-1124-Q05-02
M3 - Conference article in proceedings
T3 - Materials Research Society Symposia Proceedings
SP - 251
EP - 256
BT - Proceedings of the Scientific Basis for Nuclear Waste Management XXXII Symposium
PB - Materials Research Society
T2 - 2008 MRS Fall Meeting
Y2 - 1 December 2008 through 5 December 2008
ER -