a presentation on NAPS

1. Summer Training Presentation By-
ASHISH KUMAR
(1313340033)
B.Tech 4th year Mechanical Branch
N.I.E.T. Greater Noida

2. Contents
 Introduction of NAPS
 Layout of NAPS
 Important data of NAPS
 Working of Nuclear Power Plant
 Principal of Nuclear Power Plant
 Uranium Fuel Bundle
 Calandria
 Heavy Water
 Moderator System
 Shut Down System
 Compressed Air System
 Cooling Water
 CWPH
 Feed Water System

3. INTRODUCTION OF NAPS
• Narora atomic power station is situated at the bank of river
Ganga in Bulandshahr district of Uttar pradesh
• Naps is involved in generating electricity by utilizing nuclear
energy
• Naps is a twin unit module which develope totally 440MWe
by using uranium as a fuel and heavy water as a moderator
• Naps is laid down on 4th january 1974
• The heat generated due to fission of Natural Uranium is
removed by circulating D2O Coolant
• Naps has 2 Natural draft cooling tower and 2 Induced draft
cooling tower

4. LAYOUT OF NAPS
 Administration building
 Overhead water tank
 Natural draft cooling tower
 220KV Switch yard
 Stack
 Service building
 Reactor building
 Purification building
 Turbine building
 Pump House
 Station Training centre
 Waste Management plant

5. IMPORTANT DATA OF NAPS
Sr.No Data Specification
1. Transmission Lines
a)220 kV Narora-Moradabad
b)220kV Narora-Harduaganj
c)220kV Narora-Simbholi
d)220kV Narora-Khurja
Five:
Single line
Single line
Single line
Double line
2. Stack Height 142 Meters
3. NDCT Height 128 Meters
4. NDCT Top Dia. 58 Meters
5. NDCT Base Dia. 107 Meters
6. NDCT Throat Dia. 53 Meters
7. Steam Flow 1314 Ton/hr
8. PHT Flow 12700 Ton/hr
9. Steam Pressure 48-40 kg/cm2
10. PHT Pressure 87 Kg/cm2
11. CCW Flow 39000 Ton/hr
12. Coolant Tubes 306
13. Fuel Bundle in 1 channel 12
14. Fuel Bundle Weight 15 Kgs
15. Condenser Pressure 680mm of hg
16. R B Design Pressure 1.25 Kg/cm2
17. Station Load 18-20 Mwe
18. Generator Power 220 MWe
19. Grid Voltage 220 Kv

6. WORKING OF NUCLEAR PLANT

7. working of nuclear power plant continued...
Nuclear power plants generated electricity from
nuclear heat
The nuclear heat converts water to steam ,which in
turn drives the turbine and generator to produce
electricity
Inside a nuclear power station,energy is released by
nuclear fission in the core of nuclear reactor
1kg of Uranium U-235 produce as much energy as
the burning of 4500 tonnes of high grade variety of
coal or 2000 tonnes of oil

8. Principal of Nuclear reactor
 A Nuclear Power reactor is only a source of heat
 The heat being produced when the uranium atom splits
(fission)
 Natural uranium consist of two types (isotopes) of uranium
namely U-235 and U-238 in the ratio of 1:139
 Naturally occuring uranium contains ony 0.71% U-235,the
remainder is the non fissible U-238
 When a U-235 atom is struck by a slow (or thermal)
neutron, it splits into two or more fragments

9. Principal continued(fission)...

10. URANIUM FUEL BUNDLE

11. Uranium fuel bundle continued...
Uranium fuel bundles are 49.53 cm long & has
8.17cm dia
Each bundle consists of 19 hermetically seal
zircaloy tubes containing compact & sintered
pallets of natural uranium
Twelve such bundles are located in each fuel
channel.

12. CALANDRIA

13. calandria continued...
Calandria is the heart of reactor and it is the source
of heat
Calandria is a cylindrical vessel having 306 Calandria
tubes
One coolant tube passes through each calandria
tube, and this Coolant tube has 12 fuel Bundles in it
which undergo fission reaction

15. HEAVY WATER
 Heavy water is used as both coolant and moderator
 Heat energy is transported by coolant from reactor
to the vertical, integral U-tubes in shell type of heat
exchangers
 The absorption of heavy water for neutron is far
less than the ordinary water
 This helps in neutron economy

16. Moderator System
 Moderator system is a
heavy water and helium
system
 Calandria is always full of
moderator up to 96% and
remaining volume is
covered by helium gas
 Working pressure and
temperature of
moderator system are
8Kg/cm2 and 63 oC
respectively

17. SHUTDOWN SYSTEM
1. PRIMARY SHUTDOWN SYSTEM
-This system will response in just 2.3 sec
-This is slow down acting system
-primary shutdown system has shutoff mechanism at 14
locations in the reactor
2.SECONDARY SHUTDOWN SYSTEM
-This will used when primary system is fail to shutdown the system
- This is the fast acting system and respond in 1.4sec
-secondary shutdown system is a fast acting back up system to the primary
shutdown system

18. Compressed Air System
The compressed air system has been provided
for the supply of compressed air for the
purpose of
• Instrumentation(Instrument Air)
• Control service(Service Air)
• Mask air requirement(Mass Air)

19. CWPH
 Circulating water system is mainly for removing the latent
heat from the turbine exhaust and maintains the desired
exhaust pressure in condenser.
 Some portion of circulating water is supplied
1. Turbine oil coolers
2. Hydrogen coolers
 plant consists of six horizontal opposed balanced type air
compressors, each having nominal capacity of 14.85M3/min.
(Free air delivery = 18.0M3/min) at a pressure 8.5 Kg/cm2

21. FEED WATER SYSTEM
Feed water system main function:-
1. Supply adequate high quality water to steam
generator.
2.heat the water from about 49℃ to 170℃.
Feed water pump:-
1.Feed water pump is used to increased the
pressure 350 psi to 1200 psi.
2.Each unit typically will have 2 or 3 Feedwater
pumps.

22. Feed Water pump
Feedpumps usually rotate at about 5000 revolutions per
minute and have an oil lubricating system.