Environmental Engineering Reference
In-Depth Information
Figure 4.9 Artist
s conception (http://www-
fusion-magnetique.cea.fr/gb/fusion/principes/
principes05.htm) of ITER-based electric power
plant. In the figure, (1) marks the injection point
of DT mixture into the reaction chamber, where,
due to confinement and various heating
sources, it goes into the plasma state and burns
in fusion reactions (2). At location (3) is marked
the release of energy in the formof radiance and
fast particles and helium ash. (4) indicates the
first wall, of the vacuum chamber, marked
breeding blanket
where fast particles are
turned into heat but turn some particles into
tritons T that enter the plasma. The first wall,
breeding blanket, and vacuum chamber are
cooled by a heat extraction systemthat is used to
produce steam and supply a conventional
turbine and alternator electricity producing
system (5).
U
3.48GJ will be available. This is well beyond the 0.207 GJ needed to
heat the plasma to 1.5
¼
10MW348
¼
10
8
K.
One of the dif
culties is that the induction heating needs a conductive plasma to
start with. So there are other methods used to start the plasma before the inductive
heating. These are indicated in Figure 4.9.
Looking at Figure 4.10, note at the bottomthat the Primary fuels are Li andD. The
flow diagram indicates that Li is turned into T, some of which, along with D and
4
He,
is pumped out at the end of each heating cycle. These residues undergo isotope
separation, after which the
4
He is emitted as waste and the Tand D are reinjected as
fuel.
The
first role of the breeding blanket is to protect the vacuum vessel and magnets
from neutron and gamma radiations. In its breeding function, it produces from
lithium the tritium T needed for continued fusion reactions. Finally, it converts
neutron energy into heat and transfers that heat to a heat exchanger system. The
breeding reaction is based on neutrons from the D-T
T reaction
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