1. Numerical model of the fusion-fission hybrid system based on gas dynamic trap for transmutation of radioactive wastes
Andrey Anikeev
Institute for Neutron Physics and Reactor Technology, KIT, Karlsruhe, Germany
In collaboration with:
Budker INP
Novosibirsk
Budker Institute of Nuclear Physics, Novosibirsk, Russia (original affilation)
Institut für Sicherheitsforschung, Forschungszentrum Dresden-Rossendorf.

2. Motivation
Transmutation of long-lived radioactive nuclear waste, including plutonium, minor actinides and fission products, represents a highly important problem of fission reactor technology and is presently studied worldwide in large-scale.
Fusion-fission devices might be useful such as the production of fuel for fission reactors, direct electricity production, and closing the nuclear fuel cycle by transmuting spent nuclear fuel from fission reactors.
GDT based neutron source shows great promise in future fusion-fission applications.

3. Objectives
Numerical modelling and choice of parameters of the GDT NS as a driver in ADS-like subcritical burners.
Neutron flux > 1018 n/s
Test a GDT-DS burner capability
Requirements to MA burner systems:
energy efficiency Q=Poutel/Pinpel > 1 (self-sufficiency) !
servicing of min 5 LWRs

4. GDT plasma neutron source as irradiation facility
Background
GDT plasma neutron source as irradiation facility
Kotelnikov I.A., Mirnov V.V., Nagorny V.P., Ryutov D.D., Plasma Physics and Controlled Fusion Research, 2, IAEA, Vienna, p.309, 1985
Test zone
~ 15 m
Magnetic field : B0 1 T Neutral beams injection: D0+T0
B 15 T energy , ED/T 65 keV
Target warm plasma : total power, Pinj 36 MW
temperature Те 0.75 keV Energy consumption: MW (50 MW)
density ne 2-5 x 1020 m-3 Total fusion neutron power: MW

5. GDT plasma neutron source as irradiation facility
Background
GDT plasma neutron source as irradiation facility
Kotelnikov I.A., Mirnov V.V., Nagorny V.P., Ryutov D.D., Plasma Physics and Controlled Fusion Research, 2, IAEA, Vienna, p.309, 1985
Test zone

6. Is a compact machine  relatively low investment costs!
GDT neutron source driven system Technical idea
The technical idea would be to put up the GDT vertically and to surround both neutron production zones by a sub-critical system.
Positive features of the GDT NS:
Continuous source.
2 drivers with variable intensities.
n-zones can be longitudinally extended.
n-emission intensity can be axially profiled.
Neutron energy = 14 MeV
Is a compact machine  relatively low investment costs!

7. Preceding results Comparison of the driven sub-critical MA burners
Source:
ADS [1]
GDT basic [2]
GDT basic [2,3] Te~ 3.5 keV
GDT long [2] 2x1.5 m
GDT long [3] 2x4 m
Psuppl; MW 20 50
100
150
Pnusefull, MW
0.25 * * * *
Sn , neutron/s
1.25х1018
* 2 х 1017
* x1017
* 6.8х1017
* 1.8х1018
Pfis , MW (total)
263 87
288
378
1044
Pelout , МW (η=40%)
105 35
115
151
418
Q= Pelout / Psuppl;
5.3
0.7
2.3
1.5
2.8
MA burning rate, kg/year
( 1 LWRs = 29 kg / year)
36 (1.2)
23 (0.8)
75 (2.6)
52 (1.8)
144 (5)
* for both side of GDT (2 n-zones)
[1] G. Aliberti et al.. Nuclear Science and Eng. 146 (2004) 13.
[2] K. Noack et al. Annals of Nuclear Energy 35 (2008) 1216–1222.
[3] A. Anikeev et al. in Proc. of Cairo 11th International Conference on Energy & Environment (2009).

8. Preceding results Comparison of the driven sub-critical MA burners
Source:
ADS [1]
GDT basic [2]
GDT basic [2,3] Te~ 3.5 keV
GDT long [2] 2x1.5 m
GDT long [3] 2x4 m
Psuppl; MW 20 50
100
150
Pnusefull, MW
0.25 * * * *
Sn , neutron/s
1.25х1018
* 2 х 1017
* x1017
* 6.8х1017
* 1.8х1018
Pfis , MW (total)
263 87
288
378
1044
Pelout , МW (η=40%)
105 35
115
151
418
Q= Pelout / Psuppl;
5.3
0.7
2.3
1.5
2.8
MA burning rate, kg/year
( 1 LWRs = 29 kg / year)
36 (1.2)
23 (0.8)
75 (2.6)
52 (1.8)
144 (5)
* for both side of GDT (2 n-zones)
[1] G. Aliberti et al.. Nuclear Science and Eng. 146 (2004) 13.
[2] K. Noack et al. Annals of Nuclear Energy 35 (2008) 1216–1222.
[3] A. Anikeev et al. in Proc. of Cairo 11th International Conference on Energy & Environment (2009).

9. Study: Optimisation of the GDT neutron source
I. Improvement of the GDT basic: Electron temperature
: Te should be increased up to the self-consistent value.
– Radial confinement !
– Reduction of the electron heat losses !
GDT „Basic version“: Pinp = 50 MWel, Einj = 65 keV x
 ~3 !
: Pfis = 144 МW therm (one side)
Pfistotal = 288 MW therm (both side)
Pouttotal = 115 MWel
Q =   ~3
GDT-DS 
0.75
3.5
Te < 10-2 Einj !

10. Study: Optimisation of the GDT neutron source
I. Improvement of the GDT basic: Electron temperature
: Te should be increased up to the self-consistent value.
– Radial confinement !
– Reduction of the electron heat losses !
■ GDT experiment
♦ Estimation Te~Ph2/3
▲ Estimation Te~Ph2/7 (electron heat conductivity).

11. Study: Optimisation of the GDT neutron source
II. Improved GDT neutron source for driven system (KIT version):
Requirements:
Continuous source.
Neutron emission Sn > 1018 n/s (for each n-zones).
Neutron power flux densyty qn < 2 MW/m2 → Geometry of the n-zone.
Fusion energy efficiency Qfus ~ 1 → low energy “cost” of a neutron.
Assumptions:
Improved axial confinement → low axial loses → Te ~ 3 keV.
Vortex radial confinement → low transverse tranport.
High β ~ 60% (experimentally attained value).
Maximal magnetic field in the mirror with approriate mirror ratio.
Pilet injection → steady state plasma density.
Extended neutron emission region → 2 x 2m n-zones.

12. Study: Optimisation of the GDT neutron source
II. Improved GDT neutron source for driven system:
Instruments and methods of modeling:
A full 3D calculations by Integrated Transport Code System (ITCS).
ITCS includes modules:
MCFIT – Monte-Carlo Fast Ions Transport code – fast ions, fusion reactions.
NeuFIT – Neutral particles and gas simulations.
FITMag – Magnetic field perturbation by high pressure plasmas (β reduction).
PlasmaX – Target plasma simulations (heating, losses → temperature).
NeutronS – Neutron flux calculation.
+ Input/Output subroutines.

13. Study: Optimisation of the GDT neutron source
II. Improved GDT neutron source for driven system:
Results: Main parameters of the GDTNS_KA:
Magnetic field (SC coils):
in midplane, B T
im mirror, Bm T
lenght, L 16 m
Target warm plasma :
temperature, Те 3 keV
density, ne 5x1020 m-3
radius, a 10 cm
Neutral beams injection: D0+T0
energy, Einj 65 keV
total power, Pinj 75 MW
trapped power, Ptr 50 MW
Fussion power:
total, Pfus 15 MW
neutron, Pn 12 MW
neutron yield MW/m
Is a compact machine → low investment costs.
Electricity consumption ~ 120 MW.
2 x 2m neutron emission zones with intencivity of 1.5x1018 neutron/s

14. On axis magnetic field profile
Results: Improved GDT neutron source for driven system
On axis magnetic field profile
— vacuum magnetic field
– – beta reduced MF
n-zone

15. Axial profile of neutron yield
Results: Improved GDT neutron source for driven system
Axial profile of neutron yield
2 x 2 m neutron emission zones with intencivity of 1.5x1018 neutron/s

16. Study: Subcritical GDT driven MA burner
First analysis of proposed GDT driven subcritical reactor we made on a base of EFIT (European Facility for Industrial Transmutation) reactor design [1]. The EFIT reactor is designed to be a demonstration ADS facility for industrial scale transmutation of minor actinides, with a power of about 400 MWth. The EFIT reactor is cooled by lead. Its fuel is uranium free CERCER fuel 50% MgO +50% (Pu,MAO2) in volume, containing a large quantity of americium. The plutonium content is ~ 37% leading to Keff ~ 0.97.
In [2] several variations of EFIT design parameters were studied by using ENDF/B-6.5 based 69 group cross sections in the deterministic Sn code TWODANT. We used original (A) and extended (G) version of the EFIT reactor design for application with the GDT neutron source instead of the ADS lead target.
[1] J.U. Knebel et.al., 9th Information Exchange Meeting P&T, Nîmes, 2006
[2] M. Badea, R. Dagan, C.H.M. Broeders, Jahrestagung Kerntechnik 2007, Karlsruhe, Mai 2007

17. G A Applied EFIT-like cylindrical geometry with GDT neutron source
Study: Subcritical GDT driven MA burner
Applied EFIT-like cylindrical geometry with GDT neutron source
The fuel composition CERCER fuel 50% MgO +50% (Pu,MAO2) :
a) plutonium with weight fractions: Pu , Pu , Pu , Pu , Pu
b) MA with weight fractions: U , Np , Am , Am , Cm , Cm
Fuel
Pb Buffer
Plenum
Pb_Ext
R= cm
R 48 cm
R 30 cm
14 MeV n-source
400 cm
250 cm
R= cm
240 cm
90 cm A G

18. Pfis = 550 MW therm (one side)
Study: Subcritical GDT driven MA burner
Results of calculations
Source
ADS
GDT NS
Geometry A G
Radius (cm)
156.72
115.72
Height (cm)
240
400
Fuel height (cm) 90
250
Keff
0.9718
0.9724
0.9733
0.9741 Ks
0.9329
0.9573
0.9411
0.9577
Pfis = 550 MW therm (one side)
Pouttotal = 440 MWel (both side)
Pinp = 120 МВтel
Q = 3.7

19. Conclusions.
A new improved numerical model of the GDT neutron source based on last experimental results with a scaling to high Te ~ 3 keV and Qfus~ 0.3 was proposed and numerical simulated. The two 2 m n-zones with 1.6 MW/m neutron yield can produce 1.5x1018n/s each. It can be used for application to FDS burner of MA.
Analysis of proposed GDT driven subcritical reactor for MA burning was made on the base of the EFIT reactor design. The elongated version of EFIT with GDT-NS instead a spallation target show considerable promise for future development of this model. Detailed 3D simulation and thermohydraulic study should be made in the nex step of the project.

20. Thank you for attention!!!