Transcript Diapositiva 1 - Royal Institute of Technology

EUROTRANS
WP1.5 Safety Meeting
Lyon, October 10 - 11th 2006
Design of the EFIT-MgO/Pb Core
and Fuel Assemblies
Carlo Artioli, Massimo Sarotto
Italian Agency for new Technologies, Energy and Environment,
Advanced Physics Technology Division
Via Martiri di Monte Sole 4, 40129 Bologna, Italy
Objectives
 Transmutation of MAs
 ADS 300-400 MWth
 High PD to fast MAs incineration
Main Hypothesis
 Lead coolant:
 U-free CERCER Fuel:
T Inlet 400 °C – T Outlet 480°C
50-65% MgO VF + 50-35% (Pu,MAO2)
 Reactor Geometry, MgO VF & Fuel Enrichment E:
E = FIS / ( FERT + FIS )
FIS: PuO2 - FERT : MAO2 (Am, Cm, Np)
to satisfy: keff (t) ≤ 0,97 during the cycle
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
2
C. Artioli, M. Sarotto
Pu
[w%]
Pu238
3,737
Pu239
46,446
Pu240
34,121
Pu241
3,845
Pu242
11,850
Pu244
0,001
Pu & MA Isotopic Compositions
MOX spent Fuel after 30 years’ cooling
( CEA )
MA Vector
Pu Vector
Pu Vector
Pu238
Np237
Am241
Am242
91,8% Am
4,3% Cm
MA
[w%]
Np237
3,884
Am241
75,510
Am242
3,27E-06
Am242m
0,254
Am243
16,054
Cm242
2,3E-20
Cm243
0,066
Cm244
3,001
Cm245
1,139
Cm246
0,089
Cm247
0,002
Cm248
1,01E-04
Am242m
Pu239
Pu240
Pu241
Am243
Cm242
Cm243
Cm244
Cm245
Pu242
Pu244
Cm246
Cm247
Cm248
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
3
C. Artioli, M. Sarotto
FA Design Requirements
 Hex FAs with wrapper
 Pellet diameter as low as possible (high PD)
 Linear power f(MgO VF & conductivity)  200 [W cm-1]
 Max fuel operating Tmaxfuel = 1380 °C
 Max cladding (SS, SA213T91 coated) Tmaxclad = 550 °C
 Pb coolant velocity v  1 [m s-1]
 Residence time = 3 years: Pb corrosion is the most
restricting condition (in comparison to BUmax, DPAmax)
4
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Fuel cycle hyphotesis
For Pb corrosion (strongest requirement):
 3 years as max residence time
A
B
C
 Refuelling of 1/3 core each year
Years
A
B
C
0
0
0
0
1
1/0
1
1
2
1
2/0
2
3
2
1
3/0
4
3/0
2
1
5
1
3/0
2
6
2
1
3/0
7
3/0
2
1
8
1
3/0
2
9
2
1
3/0
Refuelling
After the first 3 years:
 Before refuelling the mean residence time is 2 years
We consider the keff beh.,
the core performances …
between [1,2] years
and the BU results (w/o
refuell.) at the 3rd year
 After refuelling the mean residence time is 1 years
4a
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Core Design Requirements (1/3)
 Pth  300-400 MWth but the size optimization criteria should be:
Min cost per kg of fissioned MAs
Min cost per MW deployed
cost / MWdeployed = f(core size, accelerator size)
increases by increasing the power
(also for the loose of φ*)
Without sufficient information and data about the unitary costs, we assume the following
semplified criterion:
decreases by increasing Pth
The largest size core acceptable within the current
spallation module design able to evacuate  11-12 MW.
The corresponding proton accelerator is: 800 MeV,
15-20 mA (to be verified)
Spallation module (19 hex FAs) fixes FA dimension
(double apothem = 191 mm)
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
5
C. Artioli, M. Sarotto
Rt
Fuel_Outer
Fuel_Inner
 Flattening Technique (2 radial fuel zones)
Target
Core Design Requirements (2/3)
DR1
DR2
Different MgO matrix contents Different Pin diameters
(fabrication more expensive
(less efficient because in the outer zone
for supplementary line cleaning) the max coolant outlet T is reached before
reaching the max allowed linear power & PD)
Coolant
Matrix
Pu+MA
Fuel
MgO VF OUT = 50%
BREST Style
Fuel
Matrix
Pu+MA
MgO VF IN = [60-65]%
Structural
Coolant
Structural
6
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
0,16
Inner & Outer FA Design
0,6
13,63 mm
191 mm
186
Fuel Inner
60-65% MgO
7,2
7,52
8,72
Fuel
Void
SS
Pb
Fuel Outer
50% MgO
178
4,91
VF(Fuel Pellet) = 21,65%
Filling r = 0,9167
(750 °C)
168+1 Fuel Pins
(7+1 pin rows)
(480 °C)
(440 °C)
7
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Core Design Requirements (3/3)
 High Burn up of MAs: f (fuel E); Low cost: f (PD)
 Limited keff (and I) variation during the cycle: f (fuel E)
 To obtain keff (t)  const
fuel E = 50%
In 3 years (AveBU = 84,75 MWd / kg (HM) )
1800
Pu & MAs mass variation
DPu / Pu (BOC)  -2,4%
1750
[ kg ]
1700
-35,1 kg (MA) / TWh
1650
Tot MA
Tot Pu
-5,9 kg (Pu) / TWh
1600
1550
DMA / MA (BOC)  -14,3%
[ years ]
1500
0
1
2
3
8
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Transmutation Performances
 Avoid Pu burning (expensive in sub-critical reactors)
 Avoid Pu Build Up (for public acceptability)
 Since we always burn  42 kg (HM) per TWh the approach could be:
f (fuel E = 45,7%)
-42 kg (MA) / TWh
0
kg (Pu) / TWh
Does not depend on Pth, DP …
The core design for this goal has to be compatible with:
• the keff (t) variations (f (fuel E) ) during the cycle
• the accelerator performances (800 MeV; 15–20 mA)
9
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Z [cm]
Calculation Tools & RZ Geometrical model
- ERANOS 2.0 – JEFF2.2 library
Beam line
Pb_Ext
Internal Lead
Target
Plenum
Fuel_Outer
45
Top_Assembly
Fuel_Inner
15
1) Cell calculations by the ECCO code
with 1968 energy groups (heterogeneous
geometry description for the Fuel Cells)
2) Spatial calculations by the BISTRO RZ
transport code (51 e. gr., RZ geometry
with “equivalent” radii to hex geometry)
AH
Pb_Ext
- Fixed:
1) fuel E (= 45,7%)
Box
Dummy
2) Spallat. Target DRt = 43,7 cm ( 19 FAs)
3) AH = 90 cm
Foot_Assembly
Box_Ax_In
DR1
DR2
4) MgO VF in fuel Outer (50%)
- Varying MgO VF in fuel IN (60, 62.5, 65 %):
DR = f(E) to obtain keff (t) ≤ 0.97
DR1 / DR2 to exploit PDcore,max1,2
DRt
DR
R [cm]
(equivalent with hexagonal rings)
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
10
C. Artioli, M. Sarotto
Keff(t) in 2 years with fuel E = 45,7%
0,97
Keff (t) during the cycle
0,968
Dkeff  550-600 pcm / year
( no matter the core size)
Keff
0,966
0,964
0,962
Pth = 365 MW (60% MgO IN)
Pth = 395 MW (62,5% MgO IN)
Pth = 430 MW (65% MgO IN)
0,96
Years
0,958
0
0,5
1
1,5
2
11
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Fuel Cycle (keff [2nd year] ≤ 0,97)
keff
2
2
0,97
average residence t [years]
Dkeff  550-600 pcm / year
0,964
1
1
Refuelling of 1/3 core
3
4
5
t [years]
Max allowable PDs (via Linear Power)
Different MgO VF
Different fuel pellet conductivity
Different LP
13
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Core performances (1/3)
(keff  0,964)
Worst
condition
(lowest keff,
highest I)
(keff  0,97)
14
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
395 MW Hex Layout (drawing by ANSALDO)
15
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Core performances (2/3)
keff = 0,964
0,97
ffrad = 1,29
ffax = 1,14
ffrad = 1,45
ffax = 1,15
16
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Core performances
(3/3)
Start Up
1 year (BOC)
2 years (EOC)
Spallation
Module
Fuel
The low keff excursion
does not require
significative proton current
variations:
-  16 mA (1 year)
-  13 mA (2 years)
17
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
BU performances (395 MW, EPu = 45,7%)
3300
TOT Pu
TOT MA
3200
3100
[ kg ]
3000
2900
DMA / MA (BOC)  -12,95%
2800
DPu / Pu (BOC)  -0,25%
2700
Years
2600
0
1
2
3
18
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
100
90
80
70
[%]
60
50
Behaviour of MA isotopes
40
30
Tot MA
Am241
Am243
Cm242
Cm244
20
10
0
0
3
2
1
years
19
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
100
90
80
Tot Pu
Pu238
Pu239
Pu242
70
Behaviour of Pu isotopes
[%]
60
50
40
30
20
10
0
0
1
Years
2
3
20
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Core and Burn Up performances
Reactor Perform.
1 year
2 years
BU perform.
3 years
Power [MWth]
395
PDMaxInnHM [W cm-3]
1306
N. Fas
48 + 174
PDMaxOutHM [W cm-3]
884
R [ cm]
43,9+38,6+74=156,5
ABUHM [MWd kg-1]
72,16
Core Vol [cm3]
6,38E+06
MA (BOC) [kg]
3256
E (Pu / (Pu+MA))
45,7% (BOC)
DMA / MA (BOC)
-13,0%
Dkg (MA)
-422
kg (MA) / TWh
-40,6
Pu (BOC) [kg]
2738
DPu / Pu (BOC)
-0,25%
Keff
0,964
0,969
Source Imp
0,59
0,61
APDHom [W cm ]
61
61
Tot ff In
1,47
1,41
Tot ff Out
1,67
1,63
I [mA] (600 MeV)
25,1
20,3
Dkg (Pu)
-7
I [mA] (800 MeV)
16,3
13,2
kg (Pu) / TWh
-0,7
-3
21
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto
Concluding Remarks
 42-0 approach for MAs transmutation (without Pu burning and production)
is a viable strategy
 The T/H analysis with RELAP code (P. Meloni) shows that we exceed
the safety limits on cladding temperature: (ffrad too high in the Outer part)
The problem can be solved by: 1) Optimising the 2 zones subdivision
2) Adopting 3 radial zones
INNER ZONE (Fax = 1.143)
Max Temperature
(°C)
Central Fuel (*)
Hot FA 1/48
Fr = 1.29
1319
OUTER ZONE (Fax =1.133)
Average FA
47/48
Hot FA
1/174
Fr = 1.45
Average FA
173/174
1094
1318
1006
 The calculations will
be refined (JEFF3.1
MgO, Pb library (1968 g),
Hex reactor model,
Surface Fuel (*)
905
790
863
719
Internal clad (**)
547
514
559
510
External clad (**)
535
504
549
503
Lead (**)
503
480
515
480
Uncertainties on MAs
nuclear data…)
* At max linear power
** At max core elevation
22
Lyon, 10 – 11th October 2006 , EUROTRANS – WP1.5 Specialist Meeting
C. Artioli, M. Sarotto