Environmental Engineering Reference
In-Depth Information
Uranium-235
Uranium-235
Uranium-235
Energy
Fission
fragment
Uranium-235
n
n
Neutron
n
n
Energy
Energy
Uranium-235
Uranium-235
n
n
Fission
fragment
Uranium-235
Energy
Uranium-235
Uranium-235
Figure 2-6
Fission of a uranium-235 nucleus by a neutron (n)
releases more neutrons that can cause multiple fissions in a
nuclear chain reaction.
Uranium-235
Reaction
conditions
After World War II, the principle of
uncontrolled
nuclear fusion
was used to develop extremely powerful
hydrogen, or thermonuclear, weapons. These weapons
use the D-T fusion reaction, in which a hydrogen-2, or
deuterium (D), nucleus and a hydrogen-3 (tritium, T)
nucleus are fused to form a helium-4 nucleus, a neu-
tron, and energy, as shown in Figure 2-7.
Scientists have also tried to develop
controlled nu-
clear fusion,
in which the D-T reaction produces heat
that can be converted into electricity. After more than
50 years of research, this process remains in the labora-
tory stage. Even if it proves technologically and eco-
nomically feasible, many energy experts do not expect
it to become a practical source of energy until at least
2030.
Fuel
Products
Proton
Neutron
Energy
+
Hydrogen-2
(deuterium nucleus)
+
+
100
million
°
C
+
+
Helium-4 nucleus
+
+
Hydrogen-3
(tritium nucleus)
Neutron
Figure 2-7
The deuterium-tritium (D-T)
nuclear fusion
reaction
takes place at extremely high temperatures.
