A nuclear fuel power plant differs from
a fossil fuel power plant in that a nuclear reactor and a specialized
boiler are substituted for the conventional furnace and boiler. The
major difference is found in the handling of nuclear fuel and boiler
room equipment. Steam still plays the dominant role in the production
of electricity.
Nuclear Energy
Nuclear energy (sometimes less
precisely referred to as atomic energy), may be defined as the energy
which is created when mass is destroyed. The equivalence of matter
and energy are expressed in Einstein’s well known equation: E = mc2
Since the velocity of light (c) is
186,000 miles per second, a very small change in mass (m) will
produce an enormous amount of energy. For one pound of mass, the
energy released will be found to be: E/lb = 38,690 billion Btu or
(assuming 13,000 Btu per pound of coal) some three billion times as
much energy in uranium (pound for pound).
However, a way has not yet been found
to convert all of a given bulk of matter to energy. Even in the
normal reaction (or fission) of uranium, only about one-thousandth of
the mass is consumed. So when one pound of uranium is fissioned, some
three-million times more energy is obtained than by burning one pound
of coal. A fantastic potential.
(To put nuclear energy into proper
perspective, while Einstein determined the relationship between
energy and mass, he also was convinced that energy derived from mass
was impossible. Others determined that it was possible, and it
remained for Fermi to demonstrate not only its possibility, but its
practicability as well.)
Nuclear Fuel
In describing the combustion of fossil
fuels, the atoms of one substance (e.g. carbon) combine with the
atoms of another (e.g. oxygen) to form a molecule of a third (e.g.
carbon dioxide), liberating heat in the process.
In nuclear fuel, energy is released by
reactions that take place within the atom itself. The atom, as small
as it is, is made up of still smaller particles and the magnitudes of
the spaces between them bear the same relative relationship as the
elements of the solar system; indeed, the atom can be portrayed as a
miniature solar system.
At the center of this system is a
nucleus. Around this small, but relatively heavy center, particles
having a negative electric charge, called electrons, spin at very
high speeds. The nucleus is made up of two kinds of particles,
protons and neutrons. Protons are positively charged particles and
usually are equal in number to the electrons.
Neutrons resemble the protons but carry
no electrical charge. Practically all of the atom’s mass is in the
nucleus; one electron has only about one two-thousandth (0.002) the
mass of the proton. To give some idea of the minuteness of relative
dimensions involved, if the nucleus was as large as a baseball,
electrons would be specks a half-mile away. The diameter of an atom,
which is also the electron orbit, is in the nature of two one-hundred
millionths (0.000,000,002) of an inch, and the diameter of the
nucleus about one ten-thousandth (0.0001) of the diameter of the
atom, or two trillionths (0.000,000,000,002) of an inch.
No comments:
Post a Comment