Career Point University

Submitted To:-

Mr. Kamal Arora

DEAN

Career Point University,Kota

Nuclear Power Plant

Fissile and Fertile Materials

Submitted By:-

Mukul Sharma (K11553)

B.Tech , 5th sem , EE

Contents Nuclear Power Plant

Components of a nuclear power plant

Nuclear Power plant Electricity Production

Advantages of Nuclear Power

Disadvantages of Nuclear Power

Fertile materialFissile materials from fertile materials

Fissile Material

List of fissile materials

Application of Fertile and Fissile material

Difference between Fissile and Fertile

Nuclear Power Plant

A nuclear power plant (nuclear power station) looks like a standard thermal power

station with one exception. The heat source in the nuclear power plant is a nuclear

reactor. As is typical in all conventional thermal power stations the heat is used to

generate steam which drives a steam turbine connected to a generator which produces

electricity.

Steam turbine is a common feature of all thermal power plants. Steam Turbine was

invented in 1884 by Sir Charles . Exceptional feature of the nuclear power plant is the

nuclear reactor and its safety and auxiliary systems.

The nuclear power plant consist of two main buildings:

Containment building (houses Nuclear Reactor)

Turbine building (houses Turbo Generator)

Components of a nuclear power plant Nuclear Reactor. A nuclear reactor is a key device of nuclear power plants. Main purpose of the

nuclear reactor is to initiate and control a sustained nuclear chain reaction.

Steam Generators. Steam generators are heat exchangers used to convert feedwater into steam from

heat produced in a nuclear reactor core. They are used in pressurized water reactors (PWR) between

the primary and secondary coolant loops.

Pressurizer. Pressure in the primary circuit is maintained by a pressurizer, a separate vessel that is

connected to the primary circuit (hot leg) and partially filled with water which is heated to the

saturation temperature (boiling point) for the desired pressure by submerged electrical heaters.

Temperature in the pressurizer can be maintained at 345 °C (653 °F).

Reactor Coolant Pumps. Reactor coolant pumps are used to pump primary coolant around the

primary circuit. These pumps are powerful, they can consume up to 6 MW each and they can be used

for heating the primary coolant before a reactor start-up.

Nuclear Power plant Electricity Production

The heat is produced by fission in a nuclear reactor and passes into the

primary cooling water. This heat, deposited in the cooling water, is conducted

to the steam generators situated in the containment building. Steam generators

produce high pressurized steam. The pressurized steam is then usually fed to a

multi-stage steam turbine. Steam turbines in western nuclear power plants are

among the largest steam turbines ever

Advantages of Nuclear Power

Nuclear electricity is reliable and relatively cheap (with an average

generating cost of 2.9 cents per kW/h) once the reactor is in place and

operating.

Large reserves of Uranium in United States - Fuel for nuclear power plants

will not run out for tens of thousands of years

Nuclear power plants contribute no greenhouse gasses and few atmospheric

pollutants

Disadvantages of Nuclear Power

Uranium is ultimately a nonrenewable resource.

Nuclear power plants are extremely costly to build.

The slight possibility that nuclear power plants can have

catastrophic failures.

Large environmental impact during the mining and processing

stages of uranium are numerous.

Nuclear waste (Spent nuclear fuel) is extremely hazardous and must

be stored safely for thousands of years.

Fertile material

Fertile material is a material that, although not itself fissionable by thermal

neutrons, can be converted into a fissile material by neutron absorption and

subsequent nuclei conversions

In nuclear engineering, fertile material (nuclide) is material that can be

converted to fissile material by neutron transmutation and subsequent nuclear

decay. The process of the transmutation of fertile materials to fissile materials is

referred to as fuel breeding. There are two basic fertile materials: 238U and 232Th.

Fissile materials from Fertile materials

A fast-neutron reactor , meaning one with little or

no neutron moderator and hence utilizing fast neutrons,

can be configured as a breeder reactor, producing more

fissile material than it consumes, using fertile material in

a blanket around the core, or contained in special fuel

rods.

Since plutonium-238, plutonium 240 and plutonium-

242 are fertile, accumulation of these and other non

fissile isotopes is less of a problem than in thermal

reactors, which cannot burn them efficiently. Breeder

reactors using thermal-spectrum neutrons are only

practical if the thorium fuel cycle is used, as uranium-

233 fissions far more reliably with thermal neutrons than

plutonium-239.

Fissile Material

In nuclear engineering, fissile material (nuclide) is material that is

capable of undergoing fission reaction after absorbing thermal (slow

or low energy) neutron. These materials are used to fuel

thermal nuclear reactors, because they are capable of sustaining

a nuclear fission chain reaction.

For heavy nuclides with atomic number of higher than 90, most of

fissile isotopes meet the fissile rule

List of fissile materials

Fissile nuclides in nuclear fuels include:

Uranium-235 which occurs in natural uranium and enriched uranium.

Plutonium-239 bred from uranium-238 by neutron capture.

Plutonium-241 bred from plutonium-240 by neutron capture. The 240Pu comes from 239Pu by the

same process.

Uranium-233 bred from thorium-232 by neutron capture.

P

Plutonium-239

Plutonium-241

U

Uranium-233

Uranium-235

Application of Fertile and fissile Materials

Fissile Material

In nuclear engineering, fissile

material is material capable of

sustaining a nuclear fission chain

reaction. By definition, fissile

material can sustain a chain reaction

with neutrons of any energy. The

predominant neutron energy may be

typified by either slow neutrons (i.e.,

a thermal system) or fast neutrons.

Fertile Material

Proposed applications for fertile material

includes a space-based facility for the

manufacture of fissile material for

spacecraft nuclear propulsion.

The facility would notionally transport

fertile materials from Earth, safely

through the atmosphere, and locate them at

a space facility at the Earth–Moon L1

Lagrangian point where man-1

Difference between Fissile and Fertile

Fissile material consist of fissionable isotopes that are capable of

undergoing nuclear fission only after capturing a thermal

neutron. 238U is not fissile isotope, because 238U cannot be fission by

thermal neutron. 238U does not meet also alternative requirement to

fissile materials. 238U is not capable of sustaining a nuclear fission

chain reaction, because neutrons produced by fission of 238U have

lower energies than original neutron (usually below the threshold

energy of 1 MeV). Typical fissile materials: 235U, 233U, 239Pu, 241Pu.

Fertile material consist of isotopes that are not fissionable by

thermal neutrons, but can be converted into fissile isotopes (after

neutron absorption and subsequent nuclear decay). Typical fertile

materials: 238U, 232Th.