Spent Fuel Reprocessing Optimisation
CHOOSE EXPERTS, FIND PARTNERSCHOOSE EXPERTS, FIND PARTNERSCHOOSE EXPERTS, FIND PARTNERSCHOOSE EXPERTS, FIND PARTNERS
OptimisationH. Druenne
Outline
•
12-13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010 2
• Nuclear in Belgium : a long story
• Optimisation of the stored spent fuel for recycling
3
1880 1986
HISTORY OF THE GDF SUEZ GROUP1895 1946 2001 20081858 19971862
ELECTROBEL
12-13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010
LYONNAISE DES EAUX ET DE L'ECLAIRAGE
TRACTIONEL
COMPAGNIEUNIVERSELLE DU CANAL MARITIME DE SUEZ
GDF SUEZ A world leader in the utilities sector
� providing electricity, gas, energy services and environmental services
- Turnover of €80 billion in 2009
- 200 000 employees
412-13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010
GDF SUEZ, A balanced electricity generation mix with nuclear
• 73 000 MW of installedgenerating capacities
• A competitive electricity
12-13/07/10 5
16%11%
1%1%
3%
Universidad Politécnica de Madrid. Cursos de verano 2010
• A competitive electricitygeneration portfolio
• Flexible, efficient and low CO2 generation facilities
• Safe and reliable nuclearpower plants.
16%
52%
11%
Nuclear
Hydro
Natural Gas
Coal
Biomass and biogas
Wind
Other non renewables
12-13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010 6
GDF SUEZ> A STREAMLINED ORGANISATION
7
KEY FIGURES 2009
Turnover of Tractebel Engineering : 460 M€
INDUSTRY 2% GDF SUEZ 47%
12-13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010
INFRASTRUCTURE 23%
POWER 42%
GAS 7%
INDUSTRY 2%
NUCLEAR 26%
GDF SUEZ 47%
THIRD PARTY 53%
Sector Client
8
STAFF
27%WOMEN
23%BRAZIL
7%INDIA-ASIA
71%71%71%71%71%ENGINEERS
12-13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010
Resources : 3.300 highly skilled people present in > 20 countries
73%MEN
MIDDLE EAST
2%13%REST OF EUROPE
55%
BELGIUM & FRANCE
29%29%29%OTHERS
NUCLEAR IN BELGIUM
A long story
12-13/07/10 9Universidad Politécnica de Madrid. Cursos de verano 2010
… but with many reversals
NUCLEAR IN BELGIUM
• 1915 – 1960 : U mine of Shinkolobwe (in Belgian Congo)
- Union Minière du Haut Katanga : the richest mine in the world at that time
- First exploited for Radium (for therapeutical uses)
12-13/07/10 10Universidad Politécnica de Madrid. Cursos de verano 2010
NUCLEAR IN BELGIUM
• 1915 – 1960 : U mine ok Shinkolobwe (in Belgian Congo)
- 1939 : African Metal
- 1942 : Manhattan project
- 1944 : tripartite agreement between GB – USA and Belgium to guarantee the
12-13/07/10 11Universidad Politécnica de Madrid. Cursos de verano 2010
- 1944 : tripartite agreement between GB – USA and Belgium to guarantee the total U production to the US in return for the participation of Belgium in future civil nuclear development.
• But …
- Most of the Belgo-Congolese U was used for military objectives
- 1946 : decision of US senator Mc Mahon to forbid any exchange of the US civil nuclear technology
NUCLEAR IN BELGIUM
In the 50’ies, everything seems possible with nuclear
• 1952 : creation of SCK/CEN one of the most famous hot labsin the world
12-13/07/10 12Universidad Politécnica de Madrid. Cursos de verano 2010
in the world = still active:manyinternational programs
AtomiumAtomium : Universal Exhibition : Universal Exhibition Brussels, 1958Brussels, 1958
NUCLEAR IN BELGIUM
1956 : BR-1 : after GB and France, Belgium (although small) is the 3rd country in Western Europe to get a core
12-13/07/10 13Universidad Politécnica de Madrid. Cursos de verano 2010
Europe to get a core critical
- Graphite-gas cooled reactor with natural U
= still in operation (research and education)
NUCLEAR IN BELGIUM
• 1961 : BR-2 : research reactor
= still operational (research on materials)
12-13/07/10 14Universidad Politécnica de Madrid. Cursos de verano 2010
NUCLEAR IN BELGIUM
• 1962 : BR-3 : first PWR in Europe
now being dismantled = full size dismantling technique
development
12-13/07/10 15Universidad Politécnica de Madrid. Cursos de verano 2010
development
Removal of the RPVCutting with plasma torch
NUCLEAR IN BELGIUM
• 1971 : founding of IRE (Institute for Radioelements)
- Mission : to contribute to public health and environmental protection
• Production of radionuclides for nuclear medecine > Worldwide leaderMajor producer of I-131First producer of Mo-99 for Europe
12-13/07/10 16Universidad Politécnica de Madrid. Cursos de verano 2010
���� 95% of exportation
• Management of radioactive waste
• Radiological monitoring of the environment (TRANSRAD)
• Consultancy projects
- 2010 : founding of IRE ELIT
NUCLEAR IN BELGIUM
Reprocessing and recycling are the reference policy
• 1957 : Belgonucléaire
- 1960 – 1970 : Development of the MIMAS (now applied in MELOX plant in F)
- 1963 : 12 MOX fuel rods in BR3 for electricity production: a world first
12-13/07/10 17Universidad Politécnica de Madrid. Cursos de verano 2010
- 1963 : 12 MOX fuel rods in BR3 for electricity production: a world first
- 1986-2006 : 660 tHM = 40 ton Pu
But shut down in 2006
Year
France
Switzerland
Germany
Belgium
Japan
0
100
200
300
400
500
600
700
1986
1997
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
NUCLEAR IN BELGIUM
• 1962 : founding of FBFC
- 1962 : first PWR fuel assembly in Europe / first MOX assembly in the world
- 1972 : first BWR fuel assembly in Europe (RBU/AEG)
- 1986 : start up of Gad fuel fabrication
12-13/07/10 18Universidad Politécnica de Madrid. Cursos de verano 2010
- 1986 : start up of Gad fuel fabrication
- 1987 / 1991 : first PWR MOX for France / Germany
- 1995 / 1998 : first BWR MOX for Germany / Japan
= still in operation
NUCLEAR IN BELGIUM
• 1966 – 1974 : EUROCHEMIC
- pilot plant for reprocessing - built in MOL with contribution of 14 OECD countries- before industrial scale in France and GB
12-13/07/10 19Universidad Politécnica de Madrid. Cursos de verano 2010
- before industrial scale in France and GB
… But extension abandoned and shutdown in 1974
> the large countries had theirown capacities and were no longer interested.
NUCLEAR IN BELGIUM
• 1967 : CHOOZ A a French-Belgian project
largest PWR in the world at that time
Shutdown in 1991
12-13/07/10 20Universidad Politécnica de Madrid. Cursos de verano 2010
• 1974 – 1975 : DOEL and TIHANGE
First power stations : reprocessing as design basis � small pools
� reprocessing contracts with La Hague
NUCLEAR IN BELGIUM
• 1974 : launch of a research program for underground repository � underground laboratory HADES
= still on going
12-13/07/10 21Universidad Politécnica de Madrid. Cursos de verano 2010
NUCLEAR IN BELGIUM
DOEL
MOL - DESSEL
2212-
13/07/10Universidad Politécnica de Madrid. Cursos de verano 2010
UNIT
Fis
sile
hei
ght
Thermal power Power uprate
programs
ICFM
LHGR
Co
re o
utl
et
tem
pe
ratu
res
Hot spot
In o
pe
rati
on
sin
ce
Nu
mb
er o
f ass
em
blie
s
Ass
em
bly
latt
ice
NS
SS
TIHANGE
[ft] [MW] [W/cm] [°C] FDH
Doel 1 1975 W 121 14*14 8 1192 -> 1311 (+10% ) PU+SGR in 2009 12 m 222 316.8 1.62Doel 2 1975 W 121 14*14 8 1192 -> 1311 (+10% ) PU+SGR in 2004 12 m 244 316.1 1.64Doel 3 1982 FRA 157 17*17 12 2775 -> 3054 (+10% ) PU+SGR in 1993 12 m (end of MOX) 196 324.7 1.62Doel 4 1985 W 157 17*17 14 2988 SGR in 1996 18 m 165 ² 327.3 1.62
Tihange 1 1975 FRA 157 15*15 12 2655 -> 2865 (+8% ) PU+SGR in 1995 18 m 238 322.2 1.64Tihange 2 1982 FRA 157 17*17 12 2775 -> 2895 (+4.3% ) PUCE in 1995
-> 3054 (+10% tot) PU+SGR in 2001 18 m 196 324.4 1.65
Tihange 3 1985 W 157 17*17 14 2988 SGR in 1998 18 m 165 ² 331.3 1.621 PU = power uprating SGR= steam generator replacement
PUCE = Power Uprate and Cycle Extension2 Typical value as for EPR
Nu
mb
er o
f ass
em
blie
s
12-13/07/10 23Universidad Politécnica de Madrid. Cursos de verano 2010
NUCLEAR IN BELGIUM
But …
• US decision to not reprocess
• TMI in 1976 + Tchernobyl in 1986
12-13/07/10 24Universidad Politécnica de Madrid. Cursos de verano 2010
� Anti nuclear movement
>> Lack of information => wrong perception of the public :
- Nuclear waste
- Danger of incidents : small probability but unmanageable in densely populated Belgium
- Risk of proliferation (dirty bomb)
NUCLEAR IN BELGIUM
• Pu is demonized !
12-13/07/10 25Universidad Politécnica de Madrid. Cursos de verano 2010
BNS Conference - 26 March 2009 25
NUCLEAR IN BELGIUM
But …
• Strong reduction of U price => economic profit questionable
12-13/07/10 26Universidad Politécnica de Madrid. Cursos de verano 2010
NUCLEAR IN BELGIUM
But …
� 1993 : Parliament decision to suspend reprocessing1998 : Government decision to cancel reprocessing contract concluded
12-13/07/10 27Universidad Politécnica de Madrid. Cursos de verano 2010
1998 : Government decision to cancel reprocessing contract concluded in 1991, but authorized 66 ton HM coming from former reprocessing to be recycled as MOX in 2 units (Tihange 2 and Doel 3) and ERU in Doel 1
Since then :
- no more reprocessing and fuel stored in interim storage on site
- reprocessing and direct disposal of spent fuel are put on equal footing
NUCLEAR IN BELGIUM
• Things are changing…
12-13/07/10 28Universidad Politécnica de Madrid. Cursos de verano 2010
NUCLEAR IN BELGIUM
• 2010 : MYRRHA = go !
- A flexible fast spectrum research reactor, is conceived as an accelerator driven system (ADS), able to operate in sub-critical and critical modes. It contains a proton accelerator, a spallation target and a multiplying medium with MOX fuel, cooled by liquid lead-bismuth (Pb-Bi).
12-13/07/10 29Universidad Politécnica de Madrid. Cursos de verano 2010
cooled by liquid lead-bismuth (Pb-Bi).
- Funds voted in march 2010
NUCLEAR IN BELGIUM
In most countries, the final back end solution
is not defined nor decided yet
� saturation of the storage capacities
12-13/07/10 30Universidad Politécnica de Madrid. Cursos de verano 2010
To face the storage capacities saturation, and according to the Government resolution, 2 solutions are studied in parallel :
build new capacities
and
reprocess the spent fuel
NUCLEAR IN BELGIUM• Situation on 1.1.2009
12-13/07/10 31Universidad Politécnica de Madrid. Cursos de verano 2010
(1) definitively unloaded since 1976(1) definitively unloaded since 1976
(2) reprocessed in UP2 plant(2) reprocessed in UP2 plant
QUANTITY OF SPENT NUCLEAR FUEL QUANTITY OF SPENT NUCLEAR FUEL ton HMton HM
3.2293.229
140140(2) reprocessed in UP2 plant(2) reprocessed in UP2 plant
(3) reprocessed in UP3 plant(3) reprocessed in UP3 plant
(4) currently stored at NPPs = (1) (4) currently stored at NPPs = (1) -- (2) (2) -- (3)(3)
(5) to be unloaded up to the end of the 40 years(5) to be unloaded up to the end of the 40 years
(6) to be disposed if no reprocessing = (4) + (5)(6) to be disposed if no reprocessing = (4) + (5)
recyclable plutonium in (6) with 55% fissile recyclable plutonium in (6) with 55% fissile
recyclable uranium in (6) with 1% U235recyclable uranium in (6) with 1% U235
532532
2.5572.557
4949
4.7004.700
2.1432.143
4.5004.500
140140
55000
Av
era
ge
dis
cha
rge
bu
rnu
p [
MW
d/t
]
55000
Av
era
ge
dis
cha
rge
bu
rnu
p [
MW
d/t
]
REPROCESS THE SPENT FUEL
• The storage capacities contain
large ranges of burnupenrichment
cooling time
12-13/07/10 32Universidad Politécnica de Madrid. Cursos de verano 2010
30000
35000
40000
45000
50000
3.5 3.6 3.7 3.8 3.9 4 4.1 4.2 4.3 4.4 4.5
Av
era
ge
dis
cha
rge
bu
rnu
p [
MW
d/t
]
Feed enrichment [%]
Ideal enrichment - average discharge
burnup dependance in annual cycle
30000
35000
40000
45000
50000
3.5 3.6 3.7 3.8 3.9 4 4.1 4.2 4.3 4.4 4.5
Av
era
ge
dis
cha
rge
bu
rnu
p [
MW
d/t
]
Feed enrichment [%]
Ideal enrichment - average discharge
burnup dependance in annual cycle
cooling time
Should the reprocessing be chosen as back end solution, then how to define the best strategy ?
REPROCESS THE SPENT FUEL
• Physics : evolution of MOX and ERU characteristics
versus burnupenrichment
cooling time
12-13/07/10 33Universidad Politécnica de Madrid. Cursos de verano 2010
cooling time
Do they meet the technical constraints ?
• Illustrative application : comparison of 2 strategies on a specific spent fuel inventory
• Conclusion
34
Cursos de
verano
201012-13/07/10
• Yield of U-232, U-234 and U-236 during irradiation
MANY TRANSMUTATIONS
U232 decay after reprocessing
U-234 and U-236 stable (half-life resp. 2.4 E+05 and 2.3 E+07 years)
MANY TRANSMUTATIONS
12-13/07/10 35
Cursos de
verano
2010
Main source of various Pu isotopes
Pu 239
Pu 238
Pu 240
Pu 241
DRH1
Slide 35
DRH1 Voir les sections 4 slides plus loin : fissions / capture = un peu moins de 2 tant pour U5 que pour Pu9
U-235 : Sur 6 neutrons absorbés, 5 fissions et 1 capture
Pu-239 : sur 4 neutrons absorbés, 3 fisisons + 1 capture
Allure des courbes d'évolution (au moins en début d'irradiation (hors disparition par fission)
Pu 239 : Evolution linéaire car production continue par absorption dans U8
Pu240 : intégrale de l'évolution du Pu239 => fonction du second degré
Pu241 : intégrale de l'évlution du Pu240 => 1 degré en plus de la précédentedruenne; 09/02/2010
12-13/07/10 36Universidad Politécnica de Madrid. Cursos de verano 2010
IMPACT OF BU ON PU AND REPU QUALITY
• Higher burnups => lower Pu and U quality
Residual Pu versus U depletion before reprocessing
0.7 96
U23
8 co
nten
t [%
]
3.8Initial ENU enrichment :Residual enrichment depending on depletion
4.5
52.9
0
0.1
0.2
0.3
0.4
0.5
0.6
0 10000 20000 30000 40000 50000Burnup UO2 [MWd/t]
Pu
cont
ent [
%] -
Am
241
[0 / 0
0]
91
92
93
94
95
U23
8 co
nten
t [%
]
PU 238PU 239PU 240PU 241PU 242Am 241U238
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 10000 20000 30000 40000 50000 60000Assembly burnup [MWd/t]
U23
5 an
d U
236
in [%
]
0.1
0.5
0.9
1.3
1.7
2.1
2.5
Pu2
36 a
nd U
232
in [p
pb]
or U
234
in [°
/00
]
U235
U236U234
U232
Pu236
12-13/07/10 37Universidad Politécnica de Madrid. Cursos de verano 2010
EQUIVALENCE PRINCIPLE
• No change in cycle energy when some ENU replaced by MOX and/or ERU
• If same kinf at EOC core average burnup• If same kinf at EOC core average burnup
• Simple approach and very good approximation(based on full core calculations)
CONSTRAINTS
• Neutronics : MOX fraction is chosen accordingly
• Storage capacities => minimum reprocessing rate
12-13/07/10 38Universidad Politécnica de Madrid. Cursos de verano 2010
• Pu max content in MOX � MOX equivalence
• MOX fabrication & transport � MOX assembly decay heat
• ERU maximum enrichment � ERU equivalence
• ERU fabrication � U-232 limit in ERU
MOX CHARACTERISTICS
• During source ENU cooling time:
Pu-241 decay
⇒ Pu quality loss
12-13/07/10 39Universidad Politécnica de Madrid. Cursos de verano 2010
9.5
10
Ave
rag
e P
u c
on
ten
t [%
]
Total Pu average content in MOX equivalent to 4.3% UOX
4.5% => 51 GWd/t
⇒ Pu quality loss
⇒ higher [Pu] in MOX
� The shorter the source ENU cooling time: the better the Pu quality => [Pu]
���� For long storage times : stabilisationEquivalence limit due to [Pu] limit
8
8.5
9
5 10 15 20 25 30 35 40 45
Ave
rag
e P
u c
on
ten
t [%
]
Storage duration before reprocessing (years)
3.8% => 41 GWd/t
Feed enrichment - discharge burnup
dependance for annual cycle
10
11
Nu
mb
er o
f ass
em
blie
s
Number of ENU assemblies to be reprocessed to get 1 MOX (equivalent to 4.3 UOX)
MOX CHARACTERISTICS
• During source ENU cooling time:
Pu-241 decay
⇒ Pu quantity losses
12-13/07/10 40Universidad Politécnica de Madrid. Cursos de verano 2010
10
11
Num
be
r of a
sse
mbl
ies
Number of ENU assemblies to be reprocessed to get 1 MOX (equivalent to 4.3 UOX)
8
9
5 10 15 20 25 30 35 40 45
Nu
mb
er o
f ass
em
blie
s
Storage duration before reprocessing (years)
Feed enrichment - discharge burnup
dependance for annual cycle
⇒ Pu quantity losses
⇒ more ENU to be reprocessedfor 1 MOX
� The shorter the source ENU cooling time:
the lesser ENU to be reprocessed
8
9
5 10 15 20 25 30 35 40 45
Num
be
r of a
sse
mbl
ies
Storage duration before reprocessing (years)
Feed enrichment - discharge burnup
dependance for annual cycle
MOX CHARACTERISTICS
• During source ENU cooling time:
Pu-238 decay
⇒ Lower PuO2 powder
12-13/07/10 41Universidad Politécnica de Madrid. Cursos de verano 2010
1000
1200
1400
De
cay
he
at [
W/a
sse
mbl
y]
Fresh MOX decay heat of 1 MOX ass. equivalent to 4.3% UOX
⇒ Lower PuO2 powder residual heat
⇒ But MOX residual heat depends also on [Pu]
�Maximum decay heat at 15 y source ENU cooling timeSmall variation but :
best as short as possibleor wait as long as necessary
400
600
800
5 10 15 20 25 30 35 40 45
De
cay
he
at [
W/a
sse
mbl
y]
Storage duration before reprocessing (years)
Feed enrichment - discharge burnup
dependance for annual cycle
4.4
4.5
2
Ach
iev
ab
le e
qu
iva
len
ce w
ith
5%
ER
U
23
6
URT quality and ERU (@ 5%) equivalence
ERU CHARACTERISTICS
• Reprocessed U quality : U-235 (fissile) / U-236 (neutron absorber)
12-13/07/10 42Universidad Politécnica de Madrid. Cursos de verano 2010
Impact of initial enrichmentand burnup 4.4
4.5
2
Ach
iev
ab
le e
qu
iva
len
ce w
ith
5%
ER
U
23
6
URT quality and ERU (@ 5%) equivalence
4
4.1
4.2
4.3
1
1.5
2
35000 40000 45000 50000 55000
Ach
iev
ab
le e
qu
iva
len
ce w
ith
5%
ER
U
U-2
35
/ U
-23
6
Source assembly burnup [MWd/t]
Feed enrichment - discharge
burnup dependance for annual cycle
But rather stable isotopes => not impacted by cooling time
� ERU enrichment limit :limited available equivalence : 4.4 to 4.25%impact on ICFM
4
4.1
4.2
4.3
1
1.5
2
35000 40000 45000 50000 55000
Ach
iev
ab
le e
qu
iva
len
ce w
ith
5%
ER
U
U-2
35
/ U
-23
6
Source assembly burnup [MWd/t]
Feed enrichment - discharge
burnup dependance for annual cycle
30%
35%
35
40
45
23
6 c
on
ten
t
U-232 content in ERU
30%
35%
35
40
45
23
6 c
on
ten
t
U-232 content in ERU
30%
35%
35
40
45
23
6 c
on
ten
t
U-232 content in ERU
U-232 decay
ERU CHARACTERISTICS
• During source ENU storage time
12-13/07/10 43Universidad Politécnica de Madrid. Cursos de verano 2010
U-232 = parent product of Tl-208 = strong gamma emitter
0%
5%
10%
15%
20%
25%
0
5
10
15
20
25
30
35
5 10 15 20 25 30 35 40
Re
lati
ve
Pu
-23
6 c
on
ten
t
U-2
32
[p
pb
]
Delay before reprocessing [years]
55 000 MWd/t
48 000 MWd/t
38 000 MWd/t
ERU enrichment : 5%
0%
5%
10%
15%
20%
25%
0
5
10
15
20
25
30
35
5 10 15 20 25 30 35 40
Re
lati
ve
Pu
-23
6 c
on
ten
t
U-2
32
[p
pb
]
Delay before reprocessing [years]
55 000 MWd/t
48 000 MWd/t
38 000 MWd/t
ERU enrichment : 5%
Accumulation
from Pu_236
decay
0%
5%
10%
15%
20%
25%
0
5
10
15
20
25
30
35
5 10 15 20 25 30 35 40
Re
lati
ve
Pu
-23
6 c
on
ten
t
U-2
32
[p
pb
]
Delay before reprocessing [years]
55 000 MWd/t
48 000 MWd/t
38 000 MWd/t
ERU enrichment : 5%
Accumulation
from Pu_236
decay
emitter
Pu-236 decay before separation
U-232 decay after separation
� ERU U-232 best for short storage times or much longer
But margins versus future limit 37 ppb
ILLUSTRATIVE APPLICATION
• Typical spent fuel stock
- Belgian stock taken as an example
• Note that reprocessing in Belgium is currently not possible without formal Government authorization
• => explorative analysis
12-13/07/10 44Universidad Politécnica de Madrid. Cursos de verano 2010
• => explorative analysis
- Huge dispersion in burnups, enrichments and cooling times
30000
35000
40000
45000
50000
55000
3.50 3.60 3.70 3.80 3.90 4.00 4.10 4.20 4.30 4.40 4.50
Bur
nup
[MW
d/t]
Feed initial enrichment [%]
ILLUSTRATIVE APPLICATION
• Comparison of 2 scenarios :
- “Hot first” : the assemblies are sent to reprocessing as soon as they have cooled enough (the older ones remains in the storage)
12-13/07/10 45Universidad Politécnica de Madrid. Cursos de verano 2010
30000
35000
40000
45000
50000
55000
3.50 3.60 3.70 3.80 3.90 4.00 4.10 4.20 4.30 4.40 4.50
Bur
nup
[MW
d/t]
Feed initial enrichment [%]
- “Cold first” : the oldest assemblies are first reprocessed
Same equivalence objective and same MOX fraction
SPENT FUEL MANAGEMENT
• For older assemblies more ENU to get 1 MOX
- “Cold first” scenario leads to a faster reduction of the storage inventory
- “Hot first” scenario strong reduction of reprocessing needs
12-13/07/10 46Universidad Politécnica de Madrid. Cursos de verano 2010
15500
7500
8500
9500
10500
11500
12500
13500
14500
15500
0 5 10 15 20 25 30
Nu
mb
er
of
ass
em
bli
es
to b
e s
tore
d
Reprocessing year from T0
Storage management
"Hot first" scenario
"Cold first" scenario
4.84.8
MOX EQUIVALENCE
• The shorter the source ENU cooling time the better the Puquality
- Hot first scenario gives better Pu => better equivalence
12-13/07/10 47Universidad Politécnica de Madrid. Cursos de verano 2010
9.6
9.8
10
10.2
10.4
10.6
4.2
4.3
4.4
4.5
4.6
4.7
0 5 10 15 20
MO
X a
ve
rag
e P
u c
on
ten
t [%
]
Av
ail
ab
le e
qu
iva
len
ce [
UO
X %
]
Reprocessing year from T0
MOX equivalence
9.6
9.8
10
10.2
10.4
10.6
4.2
4.3
4.4
4.5
4.6
4.7
0 5 10 15 20
MO
X a
ve
rag
e P
u c
on
ten
t [%
]
Av
ail
ab
le e
qu
iva
len
ce [
UO
X %
]
Reprocessing year from T0
MOX equivalence
MOX DECAY HEAT
• Maximum decay heat at 15 y cooling time:best as short as possible or wait as long as necessary
- Hot first ���� hotter MOX assemblies
still compatible
12-13/07/10 48Universidad Politécnica de Madrid. Cursos de verano 2010
MOX decay heatstill compatiblewith transportcapacities(1100 W/ass)
300
400
500
600
700
800
900
1000
1100
0 5 10 15 20
MO
X a
sse
mb
ly h
ea
t (W
)/a
ss)
Reprocessing year from T0
MOX decay heat
ERU EQUIVALENCE
• Limited available equivalence : 4.4 to 4.25%
Not dependant on source ENU cooling time
But source ENU enrich & BU => more residual U-235 for more recent ENU
12-13/07/10 49Universidad Politécnica de Madrid. Cursos de verano 2010
54.3
Hot first
���� more ERU assemblies
4.5
4.6
4.7
4.8
4.9
5
3.8
3.9
4
4.1
4.2
4.3
0 5 10 15 20
ER
U e
nri
chm
en
t [%
]
Av
ail
ab
le e
qu
iva
len
ce [
UO
X %
]
Reprocessing year from T0
ERU equivalence
ERU - RADIOPROTECTION
• Best for short storage times or much longer
- The scenarios are before or after the U-232 peak => limited impact
12-13/07/10 50Universidad Politécnica de Madrid. Cursos de verano 2010
35
ERU U-232 content
0
5
10
15
20
25
30
0 5 10 15 20
U-2
32
[p
pb
]
Reprocessing year from T0
ERU U-232 content
CONCLUSION
• For this specific case, the best choice is the “hot first scenario”
- The amount of ENU to reprocess � hot first = - 18% !
- The gains on Natural U : hot first + 3% and SWU : hot first +20%
12-13/07/10 51Universidad Politécnica de Madrid. Cursos de verano 2010
- The gains on Natural U : hot first + 3% and SWU : hot first +20% (resulting from ENU assemblies replacement by ERU and MOX)
Very attractive to think about and optimize it !
To be done for each specific case as results depend on:storage constraintsICFMequivalence objectivesacceptable MOX fraction …