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SUMMER TRAINING REPORT AT ATOMIC POWER STATION, RAWATBHATA
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A
REPORT ON
SUMMER TRANING
AT
“ELECTRIC POWER GENERATION IN RAJASTHAN
ATOMIC POWER STATION, RAWATBHATA”
SESSION-(2012-2013)
Department of Electrical Engineering
BALDEV RAM MIRDHA INSTITUTE OF TECHNOLOGY ,
JAIPUR
SUBMITTED TO: SUBMITTED BY:
MOHIT KHAROL RAKESH KUMAWAT
BMIT COLLEGE, JAIPUR B.TECH, 4th YR. (7th SEM.), EE
1 | P a g e
PREFACE
I Rakesh Kumawat student of fourth year of Electrical Engineering have
completed practical training at Rajasthan Atomic Power Station (RAPS) for 30
days from 21/05/12 to 19/06/12.
Being an engineering student, the training at Rajasthan Atomic Power Station
(RAPS) has been particularly beneficial for me. I saw various procedures,
processes and equipments used in production of electricity by nuclear power,
which were studied in books, and thus helped me in understanding of power
generation and distribution concepts of electrical power.
Rajasthan Atomic Power Station, a constituent of board of Nuclear Power
Corporation Of India Limited is a very large plant & is very difficult to acquire
complete knowledge about it in a short span. I have tried to get acquainted with
overall plant functioning and main concepts involved therein.
RAKESH KUMAWAT
Electrical Engineering
B.M.I.T.,JAIPUR.
2 | P a g e
ACKNOWLEDGEMENT
I am highly indebted and owe a sense of gratitude towards Mr.R.K.Sharma
Training Superintendent for giving me opportunity to impart training at Nuclear
Training Centre of RAJASTHAN ATOMIC POWER STATION under the
guidance of eminent professionals. It was highly educative and interactive to
take training at such a prestigious organization.
My sincere gratitude and thanks to Mr. R.C. Purohit , Senior Training Officer
and Training Co-ordinator, for providing me opportunity to complete my
training work at NTC.
I am also thankful to all those who helped me directly or indirectly through their
invaluable guidance and inspiration for successful completion of this training.
RAKESH KUMAWAT
B.M.I.T.,JAIPUR.
3 | P a g e
TABLE OF CHAPTER
S. NO. CHAPTER PAGE NO.
1. Introduction 5
2. Rajasthan Atomic Power Station 6
3. Nuclear Reactor Technology 7
4. Indian Nuclear Power 21
5. Cataloging of Nuclear Reactors 23
6. Radioactive Waste Management 28
7. Safety 30
8. RAPPCOF 33
9. Fire Section 35
10. Environmental survey laboratory 36
11. Future of the Industry 37
12. View of different stations 37
13. Conclusion 40
4 | P a g e
INTRODUCTION
Nuclear power is any nuclear technology designed to extract usable energy from
atomic nuclei via controlled nuclear reactions. The only method in use today is
through nuclear fission, though other methods might one day include nuclear
fusion and radioactive decay . All reactors heat water to produce steam, which
is then converted into mechanical work for the purpose of generating
electricity . In 2007, 14% of the world's electricity came from nuclear power.
More than 150 nuclear-powered naval vessels have been built, and a few
radioisotope rockets have been produced.
A nuclear reactor is a device in which nuclear chain reactions are initiated,
controlled, and sustained at a steady rate, as opposed to a nuclear bomb, in
which the chain reaction occurs in a fraction of a second and is uncontrolled
causing an explosion.
The most significant use of nuclear reactors is as an energy source for the
generation of electrical power and for the power in some ships .. This is usually
accomplished by methods that involve using heat from the nuclear reaction to
power steam turbines.
5 | P a g e
RAJASTHAN ATOMIC POWER STATION
UNIT-1&2
Fig.-1 Unit-3&4
6 | P a g e
Rawatbhata remote town in Chittorgarh district about 64 KMs, from Kota, an
industrial city of Rajasthan. The land selected is in between Rana Pratap Sagar
Dam &Gandhi Sagar Dam at the right bank of Chambal River. The water from
the reservoir of the Rana Pratap Sagar Dam serves the requirements of the
Nuclear Power Plants. There are four PHWR units of 100,200,220 MWe and
two units of 235 MW newly constructed which feed the Northern Grid as abase
load station. . For employees various colonies are constructed with all the
domestic facilities.
NUCLEAR REACTOR TECHNOLOGY
Just as many conventional thermal power stations generate electricity by
harnessing the thermal energy released from burning fossil fuels, nuclear power
plants convert the energy released from the nucleus of an atom, typically via
nuclear fission.
When a relatively large fissile atomic nucleus (usually uranium-235 or
plutonium-239) absorbs a neutron, a fission of the atom often results. Fission
splits the atom into two or more smaller nuclei with kinetic energy (known as
fission products) and also releases gamma radiation and free neutrons. A portion
of these neutrons may later be absorbed by other fissile atoms and create more
fissions, which release more neutrons, and so on.
This nuclear chain reaction can be controlled by using neutron poisons and
neutron moderators to change the portion of neutrons that will go on to cause
more fissions. Nuclear reactors generally have automatic and manual systems to
shut the fission reaction down if unsafe conditions are detected.
7 | P a g e
A cooling system removes heat from the reactor core and transports it to another
area of the plant, where the thermal energy can be harnessed to produce
electricity or to do other useful work. Typically the hot coolant will be used as a
heat source for a boiler, and the pressurized steam from that boiler will power
one or more steam turbine driven electrical generators.
There are many different reactor designs, utilizing different fuels and coolants
and incorporating different control schemes. Some of these designs have been
engineered to meet a specific need. Reactors for nuclear submarines and large
naval ships, for example, commonly use highly enriched uranium as a fuel. This
fuel choice increases the reactor's power density and extends the usable life of
the nuclear fuel load, but is more expensive and a greater risk to nuclear
proliferation than some of the other nuclear fuels.
A number of new designs for nuclear power generation, collectively known as
the Generation IV reactors, are the subject of active research and may be used
for practical power generation in the future. Many of these new designs
specifically attempt to make fission reactors cleaner, safer and less of a risk to
the proliferation of nuclear weapons. Fusion reactors, which may be viable in
the future, diminish or eliminate many of the risks associated with nuclear
fission
8 | P a g e
NULLEAR FISSION PROCESS
A complete chain reaction of nuclear fission is as shown in fig.
cause more fissions. In nuclear engineering, a neutron moderator is a medium
which reduces the velocity of fast neutrons, thereby turning them into thermal
neutrons capable of sustaining a nuclear chain reaction involving uranium-235.
Commonly used moderators include regular (light) water (75% of the
world's reactors), solid graphite (20% of reactors) and heavy water (5% of
reactors). Beryllium has also been used in some experimental types, and
hydrocarbons have been suggested as another possibility. Increasing or
9 | P a g e
decreasing the rate of fission will also increase or decrease the energy output
of the reactor.
CALANDRIA
It is the heart of reactor and contains fuel and moderator; it is made of
Austenitic Stainless Steel. It contains 306 horizontal calandria tubes made
form Nickel- free- Zically-2. It also contains a special tube, which has 12
fuel bundles making a total of 3672 fuel bundles. It also has 6 openings at
the top through which pass the reactivity control mechanism assemblies. In
the middle it has piping connection for moderator outlet & inlet. The entire
assembly is supported from calandria vault roof.
Heat Generation
The reactor core generates heat in a number of ways:
The kinetic energy of fission products is converted to thermal energy
when these Some of the gamma rays produced during fission are
absorbed by the reactor in the form of heat.
Heat produced by the radioactive decay of fission products and materials
that have been activated by neutron absorption. This decay heat source
will remain for some time even after the reactor is shutdown.
The heat power generated by the nuclear reaction is 1,000,000 times that of the
equal mass of coal.
TURBINE
10 | P a g e
Turbine is tandem compound machine directly coupled to electrical
generator. A turbine generally consists of low- pressure cylinder (double
flow for 500 MW units).
Turbine has a maximum continuous & economic rating of 229MW. Turbine
is the horizontal tandem compound re-heating impulse type running at
3000RPM with special provision for the extraction of moisture. A steam
turbine converts heat energy of steam into mechanical energy and drives the
generator. It uses the principle that the steam when issuing from a small
opening attains a high velocity. This velocity attained during expansion
depends on the initial and final heat content of steam. The difference
between initial & final heat content represents the heat energy converted into
mechanical energy.
STEAM GENERATORS
The boiler assemblies contain 10-u shaped shell & tube heat exchangers ,
connected in parallel. The hot coolant inlet channel and returning cold-water
channel are welded, the shell material is carbon steel & tube material is
Monel. Each heat exchangers has 195 tubes approximately 42 ft. long 4.5”
dia. 049 thou thick the design pressure on the heavy water side of the boiler
is 1350 psig at 5700 f.
COOLING
A cooling source - often water but sometimes a liquid metal - is circulated past
the reactor core to absorb the heat that it generates. The heat is carried away
from the reactor and is then used to generate steam. Most reactor systems
employ a cooling system that is physically separate from the water that will be
boiled to produce pressurized steam for the turbines, like the pressurized water
11 | P a g e
reactor. But in some reactors the water for the steam turbines is boiled directly
by the reactor core, for example the boiling water reactor.
FUEL
The use of natural uranium dioxide fuel with its it s low content of fissile
material (0.72% u-235) precludes the Possibility of a reactivity accident
during fuel handling or storage. Also, in the core there would no significant
Increase in the reactivity, in the ever of any mishaps causing redistribution of
the fuel by lattice distortion or otherwise.
The thermal characteristics namely the low thermal conductivity and high
specific heat oh UO2, permit almost all the heat generated in a fast power
transient to be initially absorbed in the fuel. Furthermore, high melting point
of UO2 permits several full power seconds of heat to be safely absorbed that
contained at normal power.
Most of the fission products remain bound in the UO2 matrix and may get
released slowly only at temperatures considerably higher than the normal
operating temperatures. Also on the account of the uranium dioxide being
chemically inert to the water coolant medium, the defected fuel releases
limited amount of radioactivity to the primary coolant system.
The use of 12 short length fuel bundles per channels in a PHWR, rather than
full- length elements covering the whole length of the core, subdivides the
escapable radioactive facility in PHWR has also the singular advantage of
allowing the defected fuel to be replaced by fresh fuel at any time.
The thin zircoloy-2/4 cladding used in fuel elements is designed to collapse
under coolant pressure on to the pellets. This feature permits high pellet-
12 | P a g e
clad gap conductance resulting in lower fuel temperature and consequently
lower fission gas release from the UO2 matrix into pellet- clad gap.
13 | P a g e
FUEL DESIGN
Fuel assemblies in the reactor are short length (half meter long) fuel bundles.
Twelve of such bundles are located in each fuel channel. The basic fuel
material is in the form of natural uranium dioxide a pellet, sheathed & sealed
in thin Zircaloy tubes. Welding them to end plates to form fuel bundles
assembles these tubes.
FUEL HANDLING
On – power fuelling is a feature of all PHWRs, which have very low excess
reactivity. In this type of reactor, refueling to compensate for fuel depletion&
for over all flux shaping to give optimum power distribution is carried out
with help of 2 fueling machines, which work in conjunction with each other
on the opposite ends of a channel. One of the machines is used to fuel the
channel while the other one accepts the fuel bundles.
In addition, the fueling machines facilitate removal of failed fuel bundles.
Each fueling machine is mounted on a bridge & column assembly. Various
mechanisms provided along tri-directional movement (X, Y&Z Direction) of
fueling machine head and make it mechanisms have been provided which
enables clamping of fueling machine head to the end fitting, opening &
closing of the respective seal plugs, shield plugs & perform various fuelling
operations i.e. receiving new fuel in the magazine from fuel transfer system,
sending spent fuel From magazine to shuttle transfer station, from shuttle
transfer station to inspection bay & from inspection bay to Spent fuel storage
bay.
14 | P a g e
MODERATOR SYSTEM
The heavy water moderator is circulated through the calandria by aid of a
low temperature & low- pressure moderator system. This system circulates
the moderator through two heat exchanges, which remove heat dissipated by
high- energy neutrons during the process of moderation. The cooled
moderator is returned to the calandria via. Moderator inlet nozzles. The high
chemical purity and low radioactivity level of the moderators are maintained
through moderator purification system. The purification systems consists of
stainless steel ion –exchange hoppers, eight numbers in 220MW contains
nuclear grade, mixed ion- exchange Resin (80% anion &20% cat ion resins).
The purification is also utilized for removable of chemical shim, boron to
affect start- up of reactor helium is used as a cover- gas over the heavy water
in calandria. The concentration deuterium in this cover –gas is control led by
circulating it using a sealed blower and passing through the recombination
containing catalyst alumina- coated with 0.3% palladium.
Primary Heat Transport (PHT) System
15 | P a g e
Primary Heat Transport (PHT) System
The system, which circulates pressurized coolant through the fuel channels
to remove the heat generated in fuel, referred as Primary Heat Transport
System. The major components of this system are the reactor fuel channels,
feeders, two inlet headers, two reactor outlet headers, four pumps &
interconnecting pipe & valves. The headers steam generators & pumps are
located above the reactor and are arranged in two symmetrical banks at
either end of the reactor. The headers are connected to fuel channels through
individual feeder pipes. Figure 6 depicts schematically the relative layout of
major equipment in one bank of the PHT system. The coolant circulation is
mentioned at all times during reactor operation, shutdown& maintenance.
REACTIVITY CONTROL
The power output of the reactor is controlled by controlling how many neutrons
are able to create more fissions.
Control rods that are made of a nuclear poison are used to absorb neutrons.
Absorbing more neutrons in a control rod means that there are fewer neutrons
available to cause fission, so pushing the control rod deeper into the reactor will
reduce its power output, and extracting the control rod will increase it.
In some reactors, the coolant also acts as a neutron moderator. A moderator
increases the power of the reactor by causing the fast neutrons that are released
from fission to lose energy and become thermal neutrons. Thermal neutrons are
more likely than fast neutrons to cause fission, so more neutron moderation
means more power output from the reactors. If the coolant is a moderator, then
temperature changes can affect the density of the coolant/moderator and
therefore change power output. A higher temperature coolant would be less
dense, and therefore a less effective moderator.
16 | P a g e
In other reactors the coolant acts as a poison by absorbing neutrons in the same
way that the control rods do. In these reactors power output can be increased by
heating the coolant, which makes it a less dense poison. Nuclear reactors
generally have automatic and manual systems to insert large amounts of poison
(boron) into the reactor to shut the fission reaction down if unsafe conditions are
detected.
ELECTRICAL POWER GENERATION
The energy released in the fission process generates heat, some of which can be
converted into usable energy. A common method of harnessing this thermal
energy is to use it to boil water to produce pressurized steam which will then
drive a steam turbine that generates electricity.
17 | P a g e
18 | P a g e
REACTOR
The reactor is used to convert nuclear energy into heat. While a reactor could be
one in which heat is produced by fusion or radioactive decay.
19 | P a g e
INDIAN NUCLEAR POWER
The Headquarters of Indian Nuclear Power Projects are located at Mumbai
known as the Department of Atomic Energy (DAE) which covers all the aspects
of R&D and power production. It is at Bhabha Atomic Research Centre where
all the research works regarding the new technologies and nuclear science.
Other than the power production plants there are various other
institutions that come under DAE like, Nuclear Fuel Compels (NFC) at
Hyderabad, Mines at Jadugura, and Centre for Advance Technology, Indore etc.
The first nuclear power plant was constructed at Tarapur in 1969. It
was a Boiling Water Reactor. The purpose of this reactor was to give the ground
for development of Pressurized Heavy Water Reactors (PHWRs). The two
units’ setup on turnkey basis by G.E., America is still working successfully.
The list of proposed sites for (PHWR) in India-
KAPP3&4 740X2
RAPP7&8 740X2
Jetpur(Maharastra) 740X2
The list of various Nuclear Power Plants in India is as follows:-
Station Rated Capacity
(MW)
Year of Criticality
TAPS-1&2 2 x 160 1969
20 | P a g e
RAPS-1 100 1972 (S/D)
RAPS-2 200 1980
RAPS-3 235 1999
RAPS-4 235 2000
RAPS-5 235 Project under construction
RAPS-6 235 Project under construction
MAPS-1 220 1983
MAPS-2 220 1985
NAPS-1 220 1989
NAPS-2 220 1991
KAPP-1 220 1992
KAPP-2 220 1993
KAIGA-1 235 1996
KAIGA-2 235 1996
KAIGA-3 235 Project under construction
KAIGA-4 235 Project under construction
TAPS-3 540 2006
TAPP-4 540 2005
MADRAS 500 F/B reactor Project under construction
Kk project 1 1000 Light water reactor under construction
Kk project 2 1000 Light water reactor under construction
CATALOGING OF NUCLEAR REACTORS
21 | P a g e
CLASSIFICATION OF REACTOR ON BASIS OF NEUTRON ENERGY:
Each fission process produces 2.5 new neutrons and, at least one of these must
produce a further fission for a chain reaction to be maintained. So for every 100
neutrons, produced in one neutron generation, at least 40 must cause further
fissions so as to produce 40 x 2.5 or 100 neutrons in the next generation. Now
the neutrons produced at fission are fast neutrons with an average energy of 2
MeV. If the fissions occur in natural uranium fuel, 99.3% of the nuclei are U-
238 is solitary responsible for the fission with neutrons having energies greater
than 1.2 MeV, therefore only half the fission neutrons can cause U-238 fissions.
So out of the 100 neutrons produced at fission, only 50 can cause U-238
fissions.
The inelastic scattering cross-section of U-238 is 10 times greater than the
fission cross-section at these neutron energies. So, out of these 50 neutrons 5
will be able to cause fission and remaining 45 will be scattered and lose so
much energy that they can no longer cause U-238 fission. The fast fission cross
section in U-235 is only 1.44 barns and U-235 fast fissions can be ignored with
so little U-235 in natural uranium. Therefore, out of the 100 fast neutrons
produced at fission only 5 will cause further fissions and produce 5 x 2.5 new
neutrons. Thus even if leakage and radioactive capture are ignored the chain
reaction can not be maintained by fast neutrons in natural uranium. One of two
alternatives is available which lead to a power reactor classification as follows:
FAST BREEDER REACTORS
The U-235 content of the fuel can be increased, i.e., the fuel is highly enriched
in U-235 with a substantial decrease in U-238. The U-235 fast fissions are thus,
considerably increased in a fast reactor. Some reduction in neutron energy does
occur due to inelastic collisions of neutrons with nuclei of the fuel and structural
material but most of the fissions are caused by neutrons of energies greater than
0.1Mev.The mass of U-235 required for the reactor to be critical varies with a
22 | P a g e
mount of U-235 enrichment. In all cases the critical mass of fissile material
required increases rapidly below 15% to 20% U-235 enrichment. To avoid large
fuel inventories a fast reactor, would require fuel containing at least 20% U-235
by volume. Incidentally the critical mass of U-235 in a fast reactor is
considerably greater than in a thermal reactor with the same fuel composition.
The highly enriched fuel, absence of moderator results in a small core.
Therefore, fast reactors have high power density cores. The average power
density in a (FBR) is 500 MW/m3 compared with 100 MW/ m3 for a (PWR). It
is therefore essential that a heat transport fluid with good thermal properties be
used. The choice is also limited to a non-moderating fluid & liquid metals seem
to satisfy both requirements. The capture cross-sections of most elements for
fast neutrons are small & since there is a relatively large mass of U-235 in the
reactor, the macroscopic capture cross-sections of structural material and fission
products are small compared with the macroscopic fission cross-section of the
U235.Consequently there is more flexibility in the choice of materials and
stainless steel can be used instead of aluminum or zirconium. Fission product
poisoning is not significant as that temperature coefficient of reactivity is low;
the excess reactivity required in a fast reactor is small.
23 | P a g e
THERMAL REACTORS
Since a chain reaction can not be maintained with fast neutrons without
considerable enrichment, the alternative is to reduce the neutron energy until the
fission cross-section of U-235 is sufficiently increased. If the neutrons are
reduced to thermal energies, the U-235 fission cross-section is 580 barns
whereas the radioactive capture cross-section is 106 barns. Thus, even allowing
for the low percentage of U-235 in natural uranium, the thermal neutron fission
cross-section in natural uranium is 4.2 barns whereas the radioactive capture
cross-section is 3.5 barns. Thus, for every 77 neutrons captured in natural
uranium about 40 will cause fission and produce 40 x 2.5 or 100 new neutrons.
For 77 neutrons out of every 100 to be captured, fewer than 23 neutrons can be
lost by escape or radioactive reaction could be sustained. In thermal reactors the
fission neutrons are thermalized by slowing them down in a moderator. Most of
the power reactors in existence are thermal reactors.
TYPES OF THERMAL REACTORS:
Previously, reactors were classified on the basis of neutron energy and the
various advantages and disadvantages of fast and thermal systems were
enumerated. It was mentioned that most of the reactor systems, at present in
operation, are thermal reactors. Thermal reactors will now be classified further
on the basis of core structure, the moderator used and the heat transport system
used. Some reference will be made to the advantages and disadvantages of each
type, but some of these considerations will be discussed later when moderator
and heat transport system properties are discussed.
24 | P a g e
TYPES OF HETROGENEOUS REACTORS:
Classification of heterogeneous reactors may be based on the type of moderator
used or on the heat transport system employed. The basic requirements &
properties of moderators & heat transport systems will be discussed at length
later. It is sufficient, for the moment to list the moderators and heat transport
fluids in general use.
The moderator may be:
Light water
Heavy water
Graphite
Organic liquids
The heat transport system may be:
Pressurized light water
Pressurized heavy water
Boiling light water
Boiling heavy water
Gases such as CO2 or helium
Liquid metals
Steam or fog
Organic liquids
HEAVY WATER MODERATED REACTORS
These have much lower neutron capture cross section than both light water and
graphite. The principal advantage of using heavy water as a moderator is,
therefore, the neutron economy that can be achieved with it. The thermal
25 | P a g e
utilization factor is increased because of lower neutron capture in the moderator.
Neutron economy is so much improved that not only can natural uranium fuel
be used, but that this fuel can be used in oxide/carbide form. Thus, there is no
longer need of enrichment plant. In addition oxide or carbide fuel improve the
fuel integrity & the fuel in less susceptible to distortion.
GRAPHITE MODERATED REACTORS
With a graphite moderator, a liquid or a gas must be used as the coolant.
Although there are water cooled graphite-moderated reactors, e.g., the Soviet
Union’s RBMK series of power stations, of which Chernobyl is one, only gas
cooled reactors will be referred to here. Whilst the United States and Canada
pioneered, respectively, the light and heavy water moderated designs, France
and United Kingdom undertook the early development of the graphite
moderated reactor, selecting carbon dioxide as the coolant because of its relative
chemical inertness and low neutron activation. France abandoned this approach
in favor of an extensive PWR programme. The UK continued to be heavily
committed to gas cooled reactors in the form, initially, of magnox and
subsequently the advanced gas cooled reactor.
PRESSURIZED HEAVY WATER REACTOR (PHWR):
PHWRs have established over the years a record for dependability, with load
factors in excess of 90% over extended periods. In the PHWR, the heavy water
moderator is contained in a large stainless steel tank (calandria) through which
runs several hundred horizontal zircaloy calandria tubes. The D2O moderator is
maintained at atmospheric pressure and a temperature of about 70°C.
Concentric with the calandria tube, but separated by a carbon dioxide filled
annulus which minimizes heat transfer from fuel to the moderator, is the
zircaloy pressure tube containing the natural UO2 fuel assemblies and the heavy
water coolant at a pressure of about 80 kg/cm² and a temperature of about
300°C.
26 | P a g e
The term pressurized refers to the pressurized D2O coolant which
flows in opposite directions in adjacent tubes and passes its heat to the
secondary coolant via the steam generators. System pressure is maintained by a
pressurizing one of the legs of a steam generator.
RADIOACTIVE WASTE MANAGEMENT
Operation of a nuclear facility like nuclear power station inevitably leads to the
production of low level radioactive wastes which are collected segregated to
select best processing method, and conditioned for either interim site storage or
for disposal. The design of facilities is such that the average public exposure
from radioactive materials at the exclusion boundary is a small fraction of the
recommended AERB limits.
SOLID RADIOACTIVE WASTE MANAGEMENT SYSTEM :
Solid radioactive waste in segregated into three general categories based on
contact dose.
Category -1 Waste: Largely originates
Protective clothing . Contaminated metal parts and miscellaneous items.As it
can contain no radioactivity. This waste will be collected in unshielded standard
drums.
Category-II & III Waste. : Filter cartridges and ion exchanges resins
Typically this waste has an unshielded radiation field greater than 1 R/hr. on
contact. These require additional shielding and greater precautions than for
category-I during transportation, handling and storage operation.
LIQUID RADIOACTIVE WASTE MANAGEMENT SYSTEM:
The Liquid Radioactive Waste Management System provides for collection,
storage, sampling and necessary treatment and dispersal of any liquid waste
27 | P a g e
produced by the station. The system is designed to control the release of
radioactivity in the liquid effluent streams so that radiations dose to members of
the public is with in those stipulated by the regulatory board. This system
handles radioactive wastes that are carried in liquid streams from the laundry
active floor drains, decontamination center and chemical laboratories.
GAS RADIOACTIVE WASTE MANAGEMENT SYSTEM:
An extensive ventilation system collects potentially active exhaust air from such
areas as the Reactor Building, the storage area, the decontamination center and
the heavy water management area. The active and potentially active exhaust air
and gases are all routed to a gaseous effluent exhaust duct. This exhaust flow is
monitored for noble gases, tritium, iodine and active particulate before being
released. Facilities for filtration are provided. Signals from the iodine, wide
range beta-gamma and particulate monitors are recorded in the control center.
Tritium monitoring is carried out by laboratory analysis.
28 | P a g e
SAFETY
INDUSTRIAL SAFETY
We mean that the measures adopted as a whole in industry to reduce accidents
to bare minimum.
Factors responsible for Safety:
Plant layout
Design of machinery
Safety Gadgets and equipments
Protective aids
Safety culture & Respect for Safety
Attitude of the management/ employer - Caution Boards
Display of Good practices about Safety
Safety meetings, Open discussion and other measures
Safety Manual
Enforcement
Unsafe Act & Unsafe conditions
Causes of Accidents:
Hazards are the risks and perils or dangers that contribute to accidents and
injuries.
"HAZARDS DO NOT CAUSE ACCIDENTS, PEOPLE DO"
29 | P a g e
Kinds of Hazards:
Fire
Heat
Material Handling
Floors
Ladders
Tools
Machinery
Walking and Working surfaces
Process
Chemicals
Electricity
Unsafe Act
Unsafe Condition
RADIATION SAFETY
Radiation in Nuclear reactor is produced in following ways :
Directly in fission reaction
By decay of fission products
Following types of radiations are encountered:
Alpha radiation
Beta radiation
Gamma radiation
Neutron radiation
Out of the above types of radiations Alpha radiation is practically zero,
whereas Beta and Gamma radiation fields may be present almost everywhere
30 | P a g e
inside the reactor building and in negligible amount even outside the reactor
building. Neutron radiations are mainly present inside the reactor vault. It is
worth noting that the secondary side of the plant i.e. feed water and steam
cycle etc. are completely separate from the nuclear systems and are therefore
not supposed to be and neither they are to carry any sort of radioactive
particle and therefore free of contamination and radiation. It is also wroth noting
that all radiations are emitted from the nucleus of every radioactive nuclide
which will always have a tendency to become stable by emitting radiations
through disintegration.
The following reaction shows the emissions of Alpha, Beta, Gamma and
Neutron.
92U238 2He4 92U234 + (alpha)
It has very low penetrating power and can be stopped by simple paper.
1H3 2He3 (18 KeV) +beta
It also does not have good penetrating power and in human skin it can penetrate
up to about half mm. It can be very easily shielded
92U235 + 0n1 92U236 Xe + Kr + 0n1 + gamma + Heat
31 | P a g e
Following methodologies are used to control the exposure to the radiation and
therefore resistive of the radiation dose.
(1) Administrative Control
(2) Zoning Technique
(3) Design Control
(4) Operation Control
(5) Maintenance and House keeping
Exposure to any kind of radiation can be controlled by an individual by
following methods:
(1) Distance
(2) Shielding
(3) Decay (Time to Decay)
RAPPCOF (COBALT FACILITY)
Here, recovery of COABALT-60 SLUGS/PELLETS from the IRRADIATEDHere, recovery of COABALT-60 SLUGS/PELLETS from the IRRADIATED
ABSORBER RODS received from different Nuclear Power Plants.ABSORBER RODS received from different Nuclear Power Plants.
2727CoCo5959 + +00nn1 1 2727CoCo6060 + +γγ
Thermal Thermal 00nn11 activation X-section: 37 Barns activation X-section: 37 Barns
Sp. Activity of Carrier free Co Sp. Activity of Carrier free Co60 60 : 1128 Ci/g: 1128 Ci/g
Half Life: 5.27 year Half Life: 5.27 year
Radiations: Radiations:
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β :0.31 MeV max. β :0.31 MeV max.
::γγ : 1.17 MeV 100%: 1.17 MeV 100%
::γγ : 1.33 MeV 100%: 1.33 MeV 100%
§Thermal Energy/1000 Ci : 4 cal/s§Thermal Energy/1000 Ci : 4 cal/s
§Radiation field at 1 mtr from 1 Ci : 1.35 R/hr§Radiation field at 1 mtr from 1 Ci : 1.35 R/hr
SLUGS/PELLETS:SLUGS/PELLETS:
The facility is designed to handle about 1 Mega Curies of Co-60. In order to
meet the demand of high and medium specific activity Co-60 and also for the
fabrication of sources of various sizes and shapes, cobalt is irradiated in the
form of nickel coated pellets of 1 mm dia x1 mm ht for production of high
specific activity Co-60 (> 100 Ci/g) and in the form of aluminum clad slugs 6
mm dia x 25 mm ht for the production of specific activity between 30-100
Ci/g.
Recovery of Co-60 from Cobalt Adjusters:
The cobalt adjusters are brought to RAPPCOF from power stations in a specialThe cobalt adjusters are brought to RAPPCOF from power stations in a special
shielding flask. For complete recovery of cobalt activity, the followingshielding flask. For complete recovery of cobalt activity, the following
operations are carried out in a sequence:operations are carried out in a sequence:
1. Discharging of adjuster into pool1. Discharging of adjuster into pool
2. Dismantling of adjuster in pool2. Dismantling of adjuster in pool
3. Transportation of sub-assemblies from pool to Recovery Cell3. Transportation of sub-assemblies from pool to Recovery Cell
4. Cell door operation4. Cell door operation
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5. Recovery of slugs/pellet capsules from sub-assemblies5. Recovery of slugs/pellet capsules from sub-assemblies
6. Recovery of pellets6. Recovery of pellets
7. Preparation of transport pencils for slugs7. Preparation of transport pencils for slugs
8. Preparation of pellet capsules for transportation8. Preparation of pellet capsules for transportation
9. Measurement of activity9. Measurement of activity
10. Loading of cobalt in transport flask10. Loading of cobalt in transport flask
11. Transportation of cobalt shielding flask11. Transportation of cobalt shielding flask
FIRE SECTION
RAPS have one common fire section from unit 1-6. It is located at 3&4 unit
area .For fire production mainly three things are required
1)fuel for burning
2) oxygen to support fire and
3) the third one is temperature.
For fire extinguishing we remove any one out of these three things.
CLASSIFICATION OF FIRE
S.
N
O
.
CLASS OF
FIRE
SOURCE OF FIRE BEST EXTINGUISER
1. A wood, paper, ordinary combustibles Soda, acid, water
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2. B Oil,paints,grease,dasoline,disel,petrol Foam, co2
3. C Fire in gaseous substances(H2) Co2 gas
4. D Fire in chemicals, metals Co2, dry chemical
5. E Electrical fire Co2, dry chemical
FIRE DETECTORS-
a.) smoke detectors
b.) temperature detectors
ENVIRONMENTAL SURVEY LABORATORY
(1)OBJECTIVES OF E.S.L. LAB AT RAWATBHATA-
Measurements of concentration of radio nuclides in various environmental
matrices collected from the environment of rawatbhata nuclear site.
ATMOSPHERIC TERRESTRIAL AQUATIC
Air tritium Soil Water
Rain water Grass Silt
Sulphide Cereals Sedim
Air particulate Pulses Fish
Milk Weed
• Measurement of internal contamination due to gamma emitting radio
nuclides by whole body counting of RAPS radiation workers.
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• Measurement of direct radiation exposure using environmental thermo
luminescent dosimeters.
• Computation of radiation does to the public and demonstrate compliance
with applicable regulatory limits
FUTURE OF INDUSTRY:
The nuclear power programme in India up to year 2020 is based on
installation of a series of MWe & 500MWe pressurized heavy water
reactor (PHWR) UNITS. 1000MWe light water reactors (LWR) coming
two 5 year plans. The total installed capacity of nuclear generation would
increase UNITS & fast breeder reactors (FBR) units. NPCIL plans to
contribute about 10% of the total additional needs of power of about
10000MWe per year i.e. 1000 MWe per year .
VIEW OF DIFFERENT STATIONS
RAJASTHAN ATOMIC POWER STATION-1&2
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RAJASTHAN ATOMIC POWER STATION-3&4
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RAJASTHAN ATOMIC POWER PROJECT-5&6
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CONCLUSION
The practical training at R.A.P.S. has proved to be quite faithful. It proved an
opportunity for encounter with such huge components like 220MW generators,
turbines, transformers and switchyards etc. The way various units are linked and
the way working of whole plant is controlled make the students realize that
engineering is not just learning the structure description and working of various
machines, but the greater part is of planning, proper management.
It also provides an opportunity to learn technology used at proper place and
time can save a lot of labor for example almost all the controls are computerized
because in running condition no any person can enter in the reactor building.
But there are few factors that require special mention. Training is not carried
out into its tree spirit. It is recommended that there should be some practical
work specially meant for students where the presence of authorities should be
ensured. There should be strict monitoring of the performance of students and
system of grading be improved on the basis of the work done. However training
has proved to be quite faithful. It has allowed as an opportunity to get an
exposure of the practical implementation to theoretical fundamental.
Prepared by :
RAKESH KUMAWAT
B.Tech (Electrical Engineering)
B.M.I.T.
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