Nuclear Reactor Comparison: Fuel, Coolant, Moderator, and Products

This presentation provides a comparative analysis of different types of nuclear reactors, primarily focusing on Pressurized Water Reactors (PWR) and Advanced Gas-Cooled Reactors (AGR). It discusses the main components of a nuclear power plant, including the electric generator, condenser, nuclear reactor, heat exchanger, and steam turbine. The presentation classifies nuclear reactors based on neutron energy, fuel used, and moderator used, detailing the working principles, advantages, and disadvantages of PWRs, including their use of enriched uranium and high-pressure water cooling systems. It further explores AGRs, highlighting their use of natural uranium, gas coolants like carbon dioxide and helium, and graphite moderators. The presentation also touches upon gas-cooled fast reactors and gas turbine modular reactors, comparing the features of AGRs and PWRs. It emphasizes the chemical reactions involved, the mechanisms of operation, and the end products and their uses, providing a systematic representation of data with referenced sources. Desklib provides access to this presentation and many other resources for students.

NUCLEAR
REACTORS

Nuclear Power Plant
Main Components
• Electric
Generator
• Condenser
• Nuclear Reactor
• Heat Exchanger
• Steam Turbine
Source: Tsumune et al. (2012)

Types of Nuclear Reactors
They are classified on the basis of:
• Neutron Energy
• Fast Reactors
• Thermal Reactors
• Fuel Used
• Natural Fuels
• Enriched Uranium
• Moderator Used
• Heavy water
• Water Moderated
• Beryllium Moderated
• Graphite Moderated
Source: Tsumune et al. (2012)

• Coolant Used
• Gas Cooled
• Liquid Metal cooled
• Organic liquid cooled
• Water cooled

Pressurized Water Reactor
• The most common nuclear reactor type,
accounting for about 60% of all the nuclear power
reactors globally
• Work by maintaining water under pressure so as
to heat but does not boil
• No mixing occurs between the water from the
reactor and that in the steam generator
• This makes most of the reactivity remain in the
reactor area
• It uses the light water cooled system of cooling

Pressurized Water Reactor
Source: Souza et al. (2014)

Working of a PWR
• Heat is created inside the reactor vessel by the core
• The generated heat is then carried by the
pressurized water in the primary coolant loop to the
steam generator
• Vaporization of the water in the secondary loop by
the heat from the primary coolant loop occurs
inside the generator leading to the production of
steam Dwyer, D. A., & Langford, T. J. (2015).
• The steam is directed to the main turbine by the
streamline making it to turn the turbine generators
which in turn produce electricity.

Heat Exchange Mechanism of Generation of Electricity in PWR
Source: Souza et al. (2014)

Layout of PWR
Fuel Used
Enriched Uranium
• The fuel has a
higher amount
of fuel that in
the uranium-235
fuels
• Uranium oxides
are used in
place of pure
uranium
• Uranium oxides are used because they are
very resistant to irradiation damage as well as
properly adopted to the extreme burn-raps
• It is quite resistant to corrosion by water
Source: Souza et al. (2014)

Advantages
Less control rods required
Ease of maintenance due to the
independence of the two
circuits of each other.
High power density which when
combined with the fact that
enriched uranium is used as the
fuel generates a highly
compact core size for a specific
output of power
• Uses water that is free from radioactive steam
hence does not call for special shielding materials
during piping
• Uses water that is cheap in cost and plenty in
supply as the coolant , moderator and reflector
Source: Féron, Herms, &
Tanguy (2012)

Disadvantages
• High temperature and high pressure in the
primary circuit promotes corrosion
• A very strong material is thus needed for the
construction of the vessel for example stainless
steel which leads to increased cost of construction
• Charging of the PWR fuel demands for a shut
down of the plant which lengthens the time into at
least some months
• Low pressure in the secondary circuit in
comparison to the primary circuit
• Low pressure values in the secondary circuit lead
to low thermal efficiency of the reactor
• Very low thermal efficiency of the plant at about
20%
•

Benefits of PWR
• They offer tremendous importance to different
militaries across the globe due to their use on
nuclear ships and naval vessels.
• The nuclear power enables the ships to navigate
over very long periods of time without calling for
refueling.
• The Pressurized Water Reactors is an excellent
reactor for the ships due to their high specific
power as it uses high pressure.
• This permits the reactors to remain fairly intact
especially if high enriched uranium is used Zhang,
L., & Wang, J. (2014).