1. THORIUM AS A FUEL FOR
NUCLEAR REACTOR
SUBMITTED BY-
MOHD ASIF SIDDIQUE
1305251022
2. INTRODUCTION
Thorium-based nuclear power is nuclear reactor-based electrical
power generation fuelled primarily by the fission of the isotope
uranium-233 produced from the fertile element thorium.
A nuclear reactor consumes certain specific fissile isotopes to
produce energy. The three most practical types of nuclear reactor
fuel are:
Uranium-235, purified (i.e. "enriched") by reducing the amount
of uranium-238 in natural mined uranium. Most nuclear power has
been generated using low-enriched uranium (LEU), whereas high-
enriched uranium (HEU) is necessary for weapons.
Plutonium-239, transmuted from uranium-238 obtained from
natural mined uranium. Plutonium is also used for weapons.
Uranium-233, transmuted from thorium-232, derived from
natural mined thorium. That is this article's subject.
3. THORIUM FUEL CYCLE
The thorium fuel cycle is a nuclear fuel cycle that uses
the isotope of thorium, 232Th, as the fertile material.
In the reactor, 232Th is transmuted into
the fissile artificial uranium isotope 233U which is the nuclear fuel.
The thorium fuel cycle claims several potential advantages over
a uranium fuel cycle-
thorium's greater abundance
superior physical and nuclear properties
better resistance to nuclear weapons
plutonium and actinide production
4. NUCLEAR REACTION WITH THORIUM
In the thorium cycle, fuel is formed
when 232Th captures a neutron (whether in a fast reactor or thermal
reactor) to become 233Th. This normally emits an electron and
an anti-neutrino (ν) by β− decay to become 233Pa. This then emits
another electron and anti-neutrino by a second β− decay to
become 233U.
6. WORLD ENERGY CONSUMPTION IS RAPIDLY ESCALATING
FUTURE ENERGY CONSUMPTION HAS BEEN SIGNIFICANTLY UNDERESTIMATED
In 2007, the world consumed*:
5.3 billion tonnes of coal
(128 quads**)
31.1 billion barrels of oil
(180 quads)
2.92 trillion m3 of natural gas
(105 quads)
65 million kg of uranium ore
(25 quads)
Contained 16,000 MT of thorium!
**1 quad = 1 quadrillion BTU = 172 million barrels (Mbbl) of crude oil
29 quads of hydroelectricity
Dominated by Hydrocarbons
Year US World
2010 108 510
2020 121 613
2030 134 722
Total Energy Demand
Projections (quads)***
In a global warming environment, where will the world turn for safe, abundant, low-cost energy?
7. THORIUM FUEL SUPPLY
Thorium is abundant around
the world and rich in energy
Estimated world reserve base
of 1.4 million MT
INDIA has about 20% of the world
reserve base
World Thorium Resources
Country
Australia
India
USA
Norway
Canada
South Africa
Brazil
Other countries
World total
Reserve Base (tons)
340,000
300,000
300,000
180,000
100,000
39,000
18,000
100,000
1,400,000
Source: U.S. Geological Survey, Mineral Commodity
Summaries, January 2008
8. ENERGY GENERATION COMPARISON
6 kg of fissile material in a liquid-fluoride
reactor has the energy equivalent (66,000
MW*hr electrical*) of:
=
230 train cars (25,000 MT) of bituminous coal or,
600 train cars (66,000 MT) of brown coal,
or, 440 million cubic feet of natural gas (15% of a
125,000 cubic meter LNG tanker),
or, 300 kg of enriched (3%) uranium in a
pressurized water reactor.
*Each ounce of thorium can therefore produce
$14,000-24,000 of electricity (at $0.04-0.07/kW*hr)
9. TYPES OF THORIUM-BASED REACTORS
HEAVY WATER REACTORS (PHWRs)
HIGH-TEMPERATURE GAS COOLED REACTORS(VHTR)
BOILING WATER REACTOR(BWR)
PRESSURIZED WATER REACTOR(PWRs)
11. OTHER APPLICATION
Industrial process heat for many uses, such as ammonia production
with the Haber process.
Desalination of water
Hydrogen production by water splitting
Combined heat and power
Nuclear marine propulsion
12. ADVANTAGES
Inherent safety
Stable coolant- Molten fluorides are chemically stable and
impervious to radiation
Low pressure operation- Because the coolant salts remain liquid at
high temperatures, LFTR cores are designed to operate at low
pressures
Leak Resistance. Due to the low pressure operation , the potential
for large leaks is also greatly reduced
Easier to control