Nuclear Energy Revision Sheet - Quia · 7 Fast breeder reactor (FBR) G 8 Steam power plant H...
Transcript of Nuclear Energy Revision Sheet - Quia · 7 Fast breeder reactor (FBR) G 8 Steam power plant H...
Question I
Identify the NPP parts by writing the number of the correct power plant part
in the blank. Select your answers from the list provided below.
1 Reactor 2 Steam
generator
3 Primary
water loop
4 Control
rods
5 Turbine–
generator
6 Secondary
water loop
7 Cooling
water
8 Transmission
lines
9 Nuclear
fuel
10 Cooling
tower
1
1
Condenser 1
2
Pressurizer 1
3
Containment
building
Question II [29 marks]
1) Fill in the table below with the required information:
Nuclear Reactor Fuel used Moderator Coolant
Boiling water reactors (BWR)
Enriched UO2
Water
Water
Pressurized
water reactors (PWR) Enriched UO2
Water
Water
Pressurized
heavy water
reactors (PHWR)-CANDU
Natural UO2
Heavy water
Light or heavy water
Advanced power reactors
(APR1400). Enriched U-235
Water
Water
Gas-cooled
reactor (GCR) Natural U/
Enriched UO2
Graphite
CO2 or Helium
2) What are the three grades of enriched Uranium and where they are used?
1. Slightly enriched uranium: has a U-235 concentration of 0.9% to 2%
Usage: is used in some heavy water reactors.
2. Low enriched uranium: has a lower than 20% concentration of U-235
Usage: For use in commercial light water reactors
3. Highly enriched uranium: has a greater than 20% concentration of U-
235.
Usage: Weapon grade uranium
3) Match the nuclear reactor or the power plant type in column (A) with the correct figure in column (B). Write your answer in the answer box provided
Column A 1 2 3 4 5 6 7 8
Column B B C A E G H D F
No Column (A) Letter Column ( B )
1
Boiling water reactors (BWR)
A
2
Pressurized water reactors
(PWR)
B
3
Pressurized heavy water
reactors (PHWR)-CANDU.
C
4
Advanced power reactors (APR1400).
D
5
Gas-cooled reactor (GCR)
E
6
Advanced Gas-cooled Reactor
(AGR)
F
7
Fast breeder reactor (FBR)
G
8
Steam power plant
H
Question III
The figure shown below for the pressurized water reactor, name the
indicated parts. Select your answers from the list provided below.
Condenser Primary loop Secondary loop
Tertiary loop
Steam Generator
Reactor coolant
pump
Reactor Pressure
Vessel
Condenser coolant pump
Turbine Electricity Generator
Fill in the indicated parts. Write
your answers in the table below.
Number Name (select from the list)
1 Reactor Pressure Vessel
2 Steam Generator
3 Primary loop
4 Turbine
5 Electricity Generator
6 Tertiary loop
7 Condenser coolant pump
8 Condenser
9 Primary loop
10 Reactor coolant pump
Question IV
1) Nuclear reactors can be classified according to their types, moderators and use.
Classify the nuclear reactors according to their usage and give examples for each one
as specified below.
Nuclear reactor usage Examples
Electricity production I. Boiling water nuclear reactor.
II. Pressurized water nuclear reactor.
Propulsion I. Nuclear marine propulsion.
II. Various proposed forms of rocket propulsion.
Heat production reactors Any two of the following:
I. Desalination plants.
II. Heat for domestic use and industrial heating.
III. Hydrogen production for use of hydrogen
economy.
Research Reactors I. Research and training material testing.
II. Production of radio isotopes for medicine and
industry.
Nuclear Fuel Production
Reactors I. The breeder reactors
II. Reactors used to produce weapon grade
plutonium
2) Differentiate between the function of the neutron poisons and the function
of neutrons moderators.
Neutron Poisons
( Absorbers)
Using neutron poisons (neutron absorbers) which absorb
excess neutrons to control the nuclear reaction.
Neutron Moderators
Using neutron moderators, which reduce the velocity of
fast neutrons, thereby turning them into thermal neutrons
which are more likely to be absorbed by other nuclei.
3) Referring to the figure shown below, describe how the steam pressure
could be reduced during accidents which cause reactor coolant leakage.
Answer:
During accidents the reactor coolant
converts to steam in the drywell and
pressure builds up quickly.
Vent pipes or tubes from the drywell
Direct the steam below the water level
in the wetwell.
This condenses the steam and reduces
the pressure
Question V
Answer the following questions:
A. For a pressurized water reactor, the containment building encloses
the following components: marks each)
I. The steam generator.
II. The entire reactor building.
III. The pressurizer.
B. There are three different containment building designs based on their
shapes, these are:
I. Can design
II. Spherical Design
III. Combined design( Can and Spherical)
C. Control rods are used to control the chain reaction in the nuclear reactor, beside that, the control system includes a number of devices
,these are:
I. Sensing elements that measure the number of neutrons.
II. Other devices to regulate the position of the control rods.
Question VI
1) Given the following reaction:
a) State the type of the above reaction.
Nuclear Fusion
Describe the reaction.
Nuclear fusion involves two atomic nuclei (Deuterium and Tritium) joining To make a large nucleus (Helium).
Energy and fast neutrons are released when this happens.
b) State two disadvantages of utilizing the heat generated by this
reaction in electrical power generation.
Any two of the following:
1. Fusion reactions can produce fast neutrons, a highly energetic and
dangerous form of nuclear reaction.
2. This requires replacing the shielding material periodically which
makes
the operation of the fusion power plant expensive and impractical.
3. Lithium can be used to slowdown these neutrons, but lithium is
chemically reactive and rare so its use is not practical. 2) In many countries, the fuel assemblies, after being in the reactor for 3 to
6 years, are stored underwater for 10 to 20 years. Suggest two reasons for using water as storage medium for spent fuel.
A. It serves as a shield to reduce the radiation levels that people
working above may be exposed to.
B. It cools the fuel assemblies that continue to produce heat (called
decay heat) for some time after removal.
3) Match the nuclear reactor or the power plant type in column (A) with the
correct figure in column (B). Write your answer in the answer box provided
Column A 1 2 3 4 5 6 7 8
Column B B C A E G H D F
No Column (A) Letter Column ( B )
1
Boiling water reactors (BWR)
A
2
Pressurized water reactors (PWR)
B
3
Pressurized heavy water reactors (PHWR)-CANDU.
C
4
Advanced power reactors
(APR1400).
D