iocl haldia refinery summer training report
DESCRIPTION
A report compiled after completing summer training at Indian Oil Corporation Limited, Haldia Refinery, Haldia, West Bengal. This report was compiled in the month of June 2013.TRANSCRIPT
Report on Summer TrainingMay - June 2013
Haldia Renery, Indian Oil Corporation Limited
Amit DattaDepartment of Mechanical Engineering,
National Institute of Technology Durgapur,Mahatma Gandhi Avenue, Durgapur, West Bengal 713209.
Haldia Refinery, IOCL | 3
Contents
Topic Page No.
Training Areas Covered 04
Acknowledgement 05
Introduction 06
Overview of Haldia Refinery 07
Haldia Refinery – Plot Plan 08
Garage and Planning 09
Workshop 19
Fuel Oil Boiler 24
DHDS 26
Thermal Power Station 28
Lube Oil Boiler 36
Offsite 39
Once-through Hydro Cracking Unit 41
Findings 46
4 | Report on Summer Training
Training areas covered:
Sl.
No. Unit Site Officer Working Dates
1. Garage and Planning Dilip Parua 17.05.13
2. Workshop Arun Bakhetia 18.05.13
3. FOB Debdut De
B. Mete 23.05.13
4. DHDS Sameer Horo
N. Ameer 24.05.13
5. TPS (Thermal Power Station) S. Sagar
A. K. Gupta 25.05.13
6. LOB (Lube Oil Block) Ranjan Naik 30.06.13
7. Offsite Tanbir Haider
Akash Lal 31.06.13
8. OHCU
R. Palo
Mauriya
V. Dwivedi
01.06.13
Haldia Refinery, IOCL | 5
Acknowledgement
The training experience in IOCL, Haldia has truly been exciting. I have come to know about many new
concepts of technology and the vivid practical experience along with theoretical knowledge have
fortified my technological know-how a lot. I would like to thank all those persons for whom this
training has been possible. I thank Shri M L Dahriya, CMNM(ML) for guiding me through the whole
training period. I express my heartiest thanks to Shri Dilip Parua (Garage and Planning), Shri Arun
Bakhetia (Workshop), Shri Debdut De & Shri B. Mete (Fuel Oil Block), Shri Sameer Horo & Shri N.
Ameer (DHDS), Shri S. Sagar & A. K. Gupta (Thermal Power Station), Shri Ranjan Naik (Lube Oil Block),
Shri Tanbir Haider & Shri Akash Lal (Offsite), Shri R.Palo, Shri Mauriya & V.Dwivedi (Once-through
Hydro Cracking Unit).
6 | Report on Summer Training
Introduction
Petroleum is derived from two words –
“petro” means rock and “oleum” means oil.
Thus the word “petroleum” means rock oil.
This is a mixture of hydrocarbons; hence it
cannot be used directly and has got to be
refined. Petroleum is refined in petroleum
refinery.
Indian Oil Corporation Ltd. (IOC) is the flagship
national oil company in the downstream sector.
The Indian Oil Group of companies owns and
operates 10 of India's 19 refineries with a
combined refining capacity of 1.2 million
barrels per day. These include two refineries of
subsidiary Chennai Petroleum Corporation Ltd.
(CPCL) and one of Bongaigaon Refinery and
Petrochemicals Limited (BRPL). The 10
refineries are located at:
Guwahati
Barauni
Koyali
Haldia
Mathura
Digboi
Panipat
Chennai
Narimanam
Bongaigaon
Indian Oil's cross-country crude oil and
product pipelines network span over 9,300 km.
It operates the largest and the widest network
of petrol & diesel stations in the country,
numbering around 16455. Indian Oil
Corporation Ltd. (Indian Oil) was formed in
1964 through the merger of Indian Oil
Company Ltd and Indian Refineries Ltd. Indian
Refineries Ltd was formed in 1958, with Feroze
Gandhi as Chairman and Indian Oil Company
Ltd. was established on 30th June 1959 with
Mr S. Nijalingappa as the first Chairman. In
1964, Indian Oil commissioned Barauni
Refinery and the first petroleum product
pipeline from Guwahati. In 1965, Gujarat
Refinery was inaugurated. In 1967, Haldia
Baraurii Pipeline (HBPL) was commissioned. In
1972, Indian Oil launched SERVO, the first
indigenous lubricant. In 1974, Indian Oil
Blending Ltd. (IOBL) became the wholly owned
subsidiary of Indian Oil. In 1975, Haldia
Refinery was commissioned. In 1981, Digboi
Refinery and Assam Oil Company's (AOC)
marketing operations came under the control
of Indian Oil. In 1982, Mathura Refinery and
Mathura-Jalandhar Pipeline (MJPL) were
commissioned. In 1994, India's First
Hydrocracker Unit was commissioned at
Gujarat Refinery.
In 1995, 1,443 km. long Kandla-Bhatinda
Pipeline (KBPL) was commissioned at Sanganer.
In 1998, Panipat Refinery was commissioned. In
the same year, Haldia, Barauni Crude Oil
Pipeline (HBCPL) was completed. In 2000,
Indian Oil crossed the turnover of Rs 1,00,000
crore and became the first Corporate in India
to do so. In the same year Indian Oil entered
into Exploration & Production (E&P) with the
award of two exploration blocks to Indian Oil
and ONGC consortium under NELP-I. In 2003,
Lanka IOC Pvt. Ltd. (LIOC) was launched in Sri
Lanka. In 2005, Indian Oil's Mathura Refinery
became the first refinery in India to attain the
capability of producing entire quantity of Euro-
III compliant diesel.
Overview of Haldia Refinery
Haldia Refinery, IOCL | 7
Overview of
Haldia Refinery
Haldia Refinery, one of the seven operating
refineries of Indian Oil, was commissioned in
January 1975. It is situated 136 km
downstream of Kolkata in the district of Purba
Medinipur, West Bengal, near the confluence
of river Hoogly and Haldi. From an original
crude oil processing capacity of 2.5 MMTPA,
the refinery is operating at a capacity of 5.8
MMTPA at present. Capacity of the refinery was
increased to 2.75 MMTPA through de-
bottlenecking in 1989-90. Refining capacity
was further increased to 3.75 MMTPA in 1997
with the installation/commissioning of second
Crude Distillation Unit of 1.0 MMTPA capacity.
Petroleum products from this refinery are
supplied mainly to eastern India through two
product pipelines as well as through barges,
tank wagons and tank trucks. Products like MS,
HSD and Bitumen are exported from this
refinery. Haldia Refinery is the only coastal
refinery of the corporation and the lone lube
flagship, apart from being the sole producer of
Jute Batching Oil. Diesel Hydro
Desulphurisation (DHDS) Unit was
commissioned in 1999, for production of low
Sulphur content (0.25% wt) High Speed Diesel
(HSD). With augmentation of this unit, refinery
is producing BS-II and Euro-III equivalent HSD
(part quantity) at present. Resid Fluidised
Catalytic Cracking Unit (RFCCU) was
commissioned in 2001 in order to increase the
distillate yield of the refinery as well as to meet
the growing demand of LPG, MS and HSD.
Refinery also produces eco-friendly Bitumen
emulsion and Microcrystalline Wax. A Catalytic
De-waxing Unit (CIDWU) was installed and
commissioned in the year 2003 for production
of high quality Lube Oil Base Stocks (LOBS),
meeting the API Gr-II standard of LOBS.
Finished products from this refinery cover both
fuel oil products as well as lube oil products.
Fuel oil products include:
LPG
Naphtha
Motor spirit (MS)
Mineral Turbine Oil (MTO)
Superior Kerosene (SK)
Aviation Turbine Fuel (ATF)
Russian Turbine Fuel (RTF)
High Speed Diesel (HSD)
Jute Batching Oil (JBO)
Furnace Oil (FO)
Lube oil base stocks are:
Inter Neutral HVI grades
Heavy Neutral HVI grades
Bright Neutral HVI grades
Besides the above, Slack wax, carbon black
feed stock (CBFS), Bitumen and Sulphur are the
other products of this refinery.
There are four main units in this refinery:
Fuel Oil Block (FOB)
Lube Oil Block (LOB)
Diesel Hydro De-Sulphurization Unit
(DHDS)
Oil Movement & Storage Unit (OM&S)
In order to meet the Euro-III fuel quality
standards, the MS Quality Improvement
Project has been commissioned in 2005 for
production of Euro-III equivalent MS. The
refinery expansion to 7.5 MMTPA as well as a
Hydrocracker project has been approved,
commissioning of which shall enable Haldia
Refinery to supply Euro-IV and Euro – III HSD
to the eastern region of India.
Haldia Refinery – Plot Plan
8 | Report on Summer Training
Haldia Refinery – Plot Plan
Figure: Haldia Refinery, Plot Plan
Chapter 1
Garage and
Planning
Garage and Planning
10 | Report on Summer Training
Diesel Engine
A diesel engine (also known as
a compression-ignition engine) is an internal
combustion engine that uses the heat of
compression to initiate ignition to burn
the fuel that has been injected into
the combustion chamber. This is in contrast to
spark-ignition engines such as a petrol engine
(gasoline engine) or gas engine (using a
gaseous fuel as opposed to gasoline), which
uses a spark plug to ignite an air-fuel mixture.
The engine was developed by German
inventor Rudolf Diesel in 1893.
The diesel engine has the highest thermal
efficiency of any regular internal or external
combustion engine due to its very
high compression ratio. Low-speed diesel
engines (as used in ships and other
applications where overall engine weight is
relatively unimportant) can have a thermal
efficiency that exceeds 50%.
Diesel engines are manufactured in two-
stroke and four-stroke versions. They were
originally used as a more efficient replacement
for stationary steam engines. Since the 1910s
they have been used in submarines and ships.
Use in locomotives, trucks, heavy
equipment and electric generating plants
followed later.
How diesel engines work
The diesel internal combustion engine differs
from the gasoline powered Otto cycle by using
highly compressed hot air to ignite the fuel
rather than using a spark plug (compression
ignition rather than spark ignition).
In the true diesel engine, only air is initially
introduced into the combustion chamber. The
air is then compressed with a compression
ratio typically between 15:1 and 22:1 resulting
in 40-bar (4.0 MPa; 580 psi) pressure compared
to 8 to 14 bars (0.80 to 1.4 MPa) (about 200
psi) in the petrol engine. This high
compression heats the air to 550 °C (1,022 °F).
At about the top of the compression stroke,
fuel is injected directly into the compressed air
in the combustion chamber. This may be into a
(typically toroidal) void in the top of the piston
or a pre-chamber depending upon the design
of the engine. The fuel injector ensures that the
fuel is broken down into small droplets, and
that the fuel is distributed evenly. The heat of
the compressed air vaporizes fuel from the
surface of the droplets. The vapour is then
ignited by the heat from the compressed air in
the combustion chamber, the droplets
continue to vaporise from their surfaces and
burn, getting smaller, until all the fuel in the
droplets has been burnt. The start of
vaporisation causes a delay period during
ignition and the characteristic diesel knocking
sound as the vapour reaches ignition
temperature and causes an abrupt increase in
pressure above the piston. The rapid expansion
of combustion gases then drives the piston
downward, supplying power to the crankshaft.
As well as the high level of compression
allowing combustion to take place without a
separate ignition system, a high compression
ratio greatly increases the engine's efficiency.
Increasing the compression ratio in a spark-
ignition engine where fuel and air are mixed
before entry to the cylinder is limited by the
need to prevent damaging pre-ignition. Since
only air is compressed in a diesel engine, and
fuel is not introduced into the cylinder until
shortly before top dead centre (TDC),
premature detonation is not an issue and
compression ratios are much higher.
Major advantages
Diesel engines have several advantages over
other internal combustion engines:
They burn less fuel than a petrol engine
performing the same work, due to the
engine's higher temperature of
combustion and greater expansion
Garage and Planning
Haldia Refinery, IOCL | 11
ratio. Gasoline engines are typically 30%
efficient while diesel engines can convert
over 45% of the fuel energy into
mechanical energy (see Carnot cycle for
further explanation).
They have no high voltage electrical
ignition system, resulting in high reliability
and easy adaptation to damp
environments. The absence of coils, spark
plug wires, etc., also eliminates a source of
radio frequency emissions which can
interfere with navigation and
communication equipment, which is
especially important in marine and aircraft
applications.
The life of a diesel engine is generally
about twice as long as that of a petrol
engine due to the increased strength of
parts used. Diesel fuel has better
lubrication properties than petrol as well.
Diesel fuel is distilled directly from
petroleum. Distillation yields some
gasoline, but the yield would be
inadequate without catalytic reforming,
which is a more costly process.
Diesel fuel is considered safer than petrol
in many applications. Although diesel fuel
will burn in open air using a wick, it will
not explode and does not release a large
amount of flammable vapor. The low
vapor pressure of diesel is especially
advantageous in marine applications,
where the accumulation of explosive fuel-
air mixtures is a particular hazard. For the
same reason, diesel engines are immune
to vapor lock.
For any given partial load the fuel
efficiency (mass burned per energy
produced) of a diesel engine remains
nearly constant, as opposed to petrol and
turbine engines which use proportionally
more fuel with partial power outputs.
They generate less waste heat in cooling
and exhaust.
Diesel engines can accept super- or turbo-
charging pressure without any natural
limit, constrained only by the strength of
engine components. This is unlike petrol
engines, which inevitably suffer detonation
at higher pressure.
The carbon monoxide content of the
exhaust is minimal, therefore diesel
engines are used in underground mines.
Biodiesel is an easily synthesized, non-
petroleum-based fuel (through trans-
esterification) which can run directly in
many diesel engines, while gasoline
engines either need adaptation to
runsynthetic fuels or else use them as an
additive to gasoline (e.g., ethanol added
to gasohol).
Supercharging and
Turbocharging
Most diesels are now turbocharged and some
are both turbo charged and supercharged.
Because diesels do not have fuel in the cylinder
before combustion is initiated, more than one
bar (100 kPa) of air can be loaded in the
cylinder without pre-ignition. A turbocharged
engine can produce significantly more power
than a naturally aspirated engine of the same
configuration, as having more air in the
cylinders allows more fuel to be burned and
thus more power to be produced. A
supercharger is powered mechanically by the
engine's crankshaft, while a turbocharger is
powered by the engine exhaust, not requiring
any mechanical power. Turbocharging can
improve the fuel economy of diesel engines by
recovering waste heat from the exhaust,
increasing the excess air factor, and increasing
the ratio of engine output to friction losses.
Garage and Planning
12 | Report on Summer Training
Turbochargers
A turbocharger, or turbo (colloquialism), from
the Latin "turbō, turbin-" ("a spinning thing") is
a forced induction device used to allow more
power to be produced by an engine of a given
size. A turbocharged engine can be more
powerful and efficient than a naturally
aspirated engine because the turbine forces
more air, and proportionately more fuel, into
the combustion chamber than atmospheric
pressure alone.
Turbochargers were originally known
as turbosuperchargers when all forced
induction devices were classified as
superchargers; nowadays the term
"supercharger" is usually applied to
only mechanically-driven forced induction
devices. The key difference between a
turbocharger and a conventional super-
charger is that the latter is mechanically driven
from the engine, often from a belt connected
to the crankshaft, whereas a turbocharger is
driven by the engine's exhaust gas turbine.
Compared to a mechanically driven
supercharger, turbo-chargers tend to be more
efficient but less responsive. Twincharger refers
to an engine which has both a supercharger
and a turbocharger.
Turbos are commonly used on truck, car, train,
and construction equipment engines. Turbos
are popularly used with Otto cycle and Diesel
cycle internal combustion engines.
Operating Principle
In most piston engines, intake gases are
"pulled" into the engine by the downward
stroke of the piston (which creates a low-
pressure area), similar to drawing liquid using a
syringe. The amount of air which is actually
inhaled, compared with the theoretical amount
if the engine could maintain atmospheric
pressure, is called volumetric efficiency. The
objective of a turbocharger is to improve an
engine's volumetric efficiency by increasing
density of the intake gas (usually air).
The turbocharger's compressor draws in
ambient air and compresses it before it enters
into the intake manifold at increased pressure.
This results in a greater mass of air entering
the cylinders on each intake stroke. The power
needed to spin the centrifugal compressor is
derived from the kinetic energy of the engine's
exhaust gases.
A turbocharger may also be used to increase
fuel efficiency without increasing power. This is
achieved by recovering waste energy in the
exhaust and feeding it back into the engine
intake. By using this otherwise wasted energy
to increase the mass of air, it becomes easier
to ensure that all fuel is burned before being
vented at the start of the exhaust stage. The
increased temperature from the higher
pressure gives a higher Carnot efficiency.
The control of turbochargers is very complex
and has changed dramatically over the 100-
plus years of its use. Modern turbochargers
can use waste gates, blow-off valves and
variable geometry.
The reduced density of intake air is often
compounded by the loss of atmospheric
density seen with elevated altitudes. Thus, a
natural use of the turbocharger is with aircraft
engines. As an aircraft climbs to higher
altitudes, the pressure of the surrounding air
quickly falls off. At 5,486 metres (17,999 ft), the
Garage and Planning
Haldia Refinery, IOCL | 13
air is at half the pressure of sea level, which
means that the engine will produce less than
half-power at this altitude.
Pressure Increase/Boost
In automotive applications, "boost" refers to
the amount by which intake manifold pressure
exceeds atmospheric pressure. This is
representative of the extra air pressure that is
achieved over what would be achieved without
the forced induction. The level of boost may
be shown on a pressure gauge, usually in bar,
psi or possibly kPa.
In aircraft engines, turbocharging is commonly
used to maintain manifold pressure
as altitude increases (i.e. to compensate for
lower-density air at higher altitudes). Since
atmospheric pressure reduces as the aircraft
climbs, power drops as a function of altitude in
normally aspirated engines. Systems that use a
turbocharger to maintain an engine's sea-level
power output are called turbo-normalized
systems. Generally, a turbo-normalized system
will attempt to maintain a manifold pressure of
29.5 inches of mercury (100 kPa).
In all turbocharger applications, boost pressure
is limited to keep the entire engine system,
including the turbo, inside its thermal and
mechanical design operating range. Over-
boosting an engine frequently causes damage
to the engine in a variety of ways including
pre-ignition, overheating, and over-stressing
the engine's internal hardware.
For example, to avoid engine knocking (aka
detonation) and the related physical damage
to the engine, the intake manifold pressure
must not get too high, thus the pressure at the
intake manifold of the engine must be
controlled by some means. Opening the waste
gate allows the excess energy destined for the
turbine to bypass it and pass directly to the
exhaust pipe, thus reducing boost pressure.
The waste gate can be either controlled
manually (frequently seen in aircraft) or by an
actuator (in automotive applications, it is often
controlled by the Engine Control Unit).
Intercooling
When the pressure of the engine's intake air is
increased, its temperature will also increase. In
addition, heat soak from the hot exhaust gases
spinning the turbine may also heat the intake
air. The warmer the intake air the less dense,
and the less oxygen available for the
combustion event, which reduces volumetric
efficiency. Not only does excessive intake-air
temperature reduce efficiency, it also leads to
engine knock, or detonation, which is
destructive to engines.
Turbocharger units often make use of
an intercooler (also known as a charge air
cooler), to cool down the intake air.
Intercoolers are often tested for leaks during
routine servicing, particularly in trucks where a
leaking intercooler can result in a 20%
reduction in fuel economy.
(Note that "intercooler" is the proper term for
the air cooler between successive stages of
boost, whereas "charge air cooler" is the
proper term for the air cooler between the
boost stage(s) and the appliance that will
consume the boosted air.)
Garage and Planning
14 | Report on Summer Training
Transmission
A machine consists of a power source and a
power transmission system, which provides
controlled application of the power. Merriam-
Webster defines transmission as an assembly
of parts including the speed-changing gears
and the propeller shaft by which the power is
transmitted from an engine to a live
axle. Often transmission refers simply to
the gearbox that uses gears and gear trains to
provide speed and torque conversions from a
rotating power source to another device.
In British English, the term transmission refers
to the whole drive train, including clutch,
gearbox, prop shaft (for rear-wheel drive),
differential, and final drive shafts. In American
English, however, a gearbox is any device that
converts speed and torque, whereas a
transmission is a type of gearbox that can be
“shifted” to dynamically change the speed-
torque ratio such as in a vehicle.
The most common use is in motor vehicles,
where the transmission adapts the output of
the internal combustion engine to the drive
wheels. Such engines need to operate at a
relatively high rotational speed, which is
inappropriate for starting, stopping, and slower
travel. The transmission reduces the higher
engine speed to the slower wheel speed,
increasing torque in the process. Transmissions
are also used on pedal bicycles, fixed
machines, and anywhere rotational speed and
torque must be adapted.
Often, a transmission has multiple gear ratios
(or simply “gears”), with the ability to switch
between them as speed varies. This switching
may be done manually (by the operator), or
automatically. Directional (forward and reverse)
control may also be provided. Single-ratio
transmissions also exist, which simply change
the speed and torque (and sometimes
direction) of motor output.
In motor vehicles, the transmission generally is
connected to the engine crankshaft via a
flywheel and/or clutch and/or fluid coupling.
The output of the transmission is transmitted
via driveshaft to one or more differentials,
which in turn, drive the wheels. While a
differential may also provide gear reduction, its
primary purpose is to permit the wheels at
either end of an axle to rotate at different
speeds (essential to avoid wheel slippage on
turns) as it changes the direction of rotation.
Conventional gear/belt transmissions are not
the only mechanism for speed/torque
adaptation. Alternative mechanisms
include torque converters and power
transformation (for example, diesel-electric
transmission and hydraulic drive system).
Hybrid configurations also exist.
Manual type
Manual transmissions come in two basic types:
A simple but rugged sliding-
mesh or unsynchronized/non-
synchronous system, where straight-cut
spur gear sets spin freely, and must be
synchronized by the operator matching
engine revs to road speed, to avoid noisy
and damaging clashing of the gears
The now common constant-
mesh gearboxes, which can include non-
synchronised,
or synchronized/synchromesh systems,
where typically diagonal cut helical (or
sometimes either straight-cut, or double-
helical) gear sets are constantly "meshed"
together, and a dog clutch is used for
changing gears. On synchromesh boxes,
friction cones or "synchro-rings" are used
in addition to the dog clutch to closely
match the rotational speeds of the two
sides of the (declutched) transmission
before making a full mechanical
engagement.
The former type was standard in many vintage
cars (alongside e.g. epicyclic and multi-clutch
systems) before the development of constant-
Garage and Planning
Haldia Refinery, IOCL | 15
mesh manuals and hydraulic-epicyclic
automatics, older heavy-duty trucks, and can
still be found in use in some agricultural
equipment. The latter is the modern standard
for on- and off-road transport manual and
semi-automatic transmission, although it may
be found in many forms; e.g., non-
synchronised straight-cut in racetrack or
super-heavy-duty applications, non-synchro
helical in the majority of heavy trucks and
motorcycles and in certain classic cars (e.g. the
Fiat 500), and partly or fully synchronised
helical in almost all modern manual-shift
passenger cars and light trucks.
Automatic type
Most modern cars have an automatic
transmission that selects an appropriate gear
ratio without any operator intervention. They
primarily use hydraulics to select gears,
depending on pressure exerted by fluid within
the transmission assembly. Rather than using
a clutch to engage the transmission, a fluid
flywheel, or torque converter is placed in
between the engine and transmission. It is
possible for the driver to control the number
of gears in use or select reverse, though
precise control of which gear is in use may or
may not be possible.
Automatic transmissions are easy to use.
However, in the past, automatic transmissions
of this type have had a number of problems;
they were complex and expensive, sometimes
had reliability problems (which sometimes
caused more expenses in repair), have often
been less fuel-efficient than their manual
counterparts (due to "slippage" in the torque
converter), and their shift time was slower than
a manual making them uncompetitive for
racing. With the advancement of modern
automatic transmissions this has changed.
Attempts to improve fuel efficiency of
automatic transmissions include the use
of torque converters that lock up beyond a
certain speed or in higher gear ratios,
eliminating power loss, and overdrive gears
that automatically actuate above certain
speeds. In older transmissions, both
technologies could be intrusive, when
conditions are such that they repeatedly cut in
and out as speed and such load factors as
grade or wind vary slightly. Current
computerized transmissions possess complex
programming that both maximizes fuel
efficiency and eliminates intrusiveness. This is
due mainly to electronic rather than
mechanical advances, though improvements
in CVT technology and the use of automatic
clutches have also helped. The 2012 model of
the Honda Jazz sold in the UK actually claims
marginally better fuel consumption for the CVT
version than the manual version.
For certain applications, the slippage inherent
in automatic transmissions can be
advantageous. For instance, in drag racing, the
automatic transmission allows the car to stop
with the engine at a high rpm (the "stall
speed") to allow for a very quick launch when
the brakes are released. In fact, a common
modification is to increase the stall speed of
the transmission. This is even more
advantageous for turbocharged engines,
where the turbocharger must be kept spinning
at high rpm by a large flow of exhaust to
maintain the boost pressure and eliminate
the turbo lag that occurs when the throttle
suddenly opens on an idling engine.
Garage and Planning
16 | Report on Summer Training
Cranes
A crane is a type of machine, generally
equipped with a hoist, wire ropes or chains,
and sheaves, that can be used both to lift and
lower materials and to move them horizontally.
It is mainly used for lifting heavy things and
transporting them to other places. It uses one
or more simple machines to create mechanical
advantage and thus move loads beyond the
normal capability of a man. Cranes are
commonly employed in the transport industry
for the loading and unloading of freight, in
the construction industry for the movement of
materials and in the manufacturing industry for
the assembling of heavy equipment.
The first construction cranes were invented by
the Ancient Greeks and were powered by men
or beasts of burden, such as donkeys. These
cranes were used for the construction of tall
buildings. Larger cranes were later developed,
employing the use of human treadwheels,
permitting the lifting of heavier weights. In
the High Middle Ages, harbour cranes were
introduced to load and unload ships and assist
with their construction – some were built into
stone towers for extra strength and stability.
The earliest cranes were constructed from
wood, but cast iron and steel took over with
the coming of the Industrial Revolution.
For many centuries, power was supplied by the
physical exertion of men or animals, although
hoists in watermills and windmills could be
driven by the harnessed natural power. The
first 'mechanical' power was provided by steam
engines, the earliest steam crane being
introduced in the 18th or 19th century, with
many remaining in use well into the late 20th
century. Modern cranes usually use internal
combustion engines or electric motors and
hydraulic systems to provide a much greater
lifting capability than was previously possible,
although manual cranes are still utilised where
the provision of power would be uneconomic.
Cranes exist in an enormous variety of forms –
each tailored to a specific use. Sometimes sizes
range from the smallest jib cranes, used inside
workshops, to the tallest tower cranes, used for
constructing high buildings. For a while, mini -
cranes are also used for constructing high
buildings, in order to facilitate constructions by
reaching tight spaces. Finally, we can find
larger floating cranes, generally used to build
oil rigs and salvage sunken ships.
Garage and Planning
Haldia Refinery, IOCL | 17
Fork-lifts
A fork-lift truck (also called a lift truck,
a fork truck, or a fork-lift) is a powered
industrial truck used to lift and transport
materials. The modern fork-lift was developed
in the 1960s by various companies including
the transmission manufacturing company
Clark and the hoist company Yale & Towne
Manufacturing. The forklift has since become
an indispensable piece of equipment in
manufacturing and warehousing operations.
Counterbalanced fork-lift
components
A typical counterbalanced forklift contains the
following components:
Truck Frame - is the base of the machine
to which the mast, axles, wheels,
counterweight, overhead guard and power
source are attached. The frame may have
fuel and hydraulic fluid tanks constructed
as part of the frame assembly.
Counterweight - is a mass attached to the
rear of the forklift truck frame. The
purpose of the counterweight is to
counterbalance the load being lifted. In an
electric forklift the large lead-acid battery
itself may serve as part of the
counterweight.
Cab - is the area that contains a seat for
the operator along with the control
pedals, steering wheel, levers,
switches and a dashboard containing
operator readouts. The cab area may be
open air or enclosed, but it is covered by
the cage-like overhead guard assembly.
The 'Cab' can also be equipped with a Cab
Heater for cold climate countries.
Overhead Guard - is a
metal roof supported by posts at each
corner of the cab that helps protect the
operator from any falling objects. On
some forklifts, the overhead guard is an
integrated part of the frame assembly.
Power Source - may consist of an internal
combustion engine that can be powered
by LP gas, CNG gas, gasoline or diesel fuel.
Electric forklifts are powered by either
a battery or fuel cells that provides power
to the electric motors. The electric motors
used on a forklift may be
either DC or AC types.
Tilt Cylinders - are hydraulic cylinders
that are mounted to the truck frame and
the mast. The tilt cylinders pivot the mast
to assist in engaging a load.
Mast - is the vertical assembly that does
the work of raising and lowering the load.
It is made up of interlocking rails that also
provide lateral stability. The interlocking
rails may either have rollers or bushings as
guides. The mast is driven hydraulically,
and operated by one or more hydraulic
cylinders directly or using chains from the
cylinder/s. It may be mounted to the front
axle or the frame of the forklift.
Carriage - is the component to which the
forks or other attachments mount. It is
mounted into and moves up and down
the mast rails by means of chains or by
being directly attached to the hydraulic
cylinder. Like the mast, the carriage may
have either rollers or bushings to guide it
in the interlocking mast rails.
Load Back Rest - is a rack-like extension
that is either bolted or welded to the
carriage in order to prevent the load from
shifting backward when the carriage is
lifted to full height.
Attachments - may consist of forks or
tines that are the L-shaped members that
engage the load. A variety of other types
of material handling attachments are
available. Some attachments include
sideshifters, slipsheet attachments, carton
clamps, multipurpose clamps, rotators,
fork positioners, carpet poles, pole
handlers, container handlers and roll
clamps.
Garage and Planning
18 | Report on Summer Training
Tires - either solid for indoor use,
or pneumatic for outside use.
Attachments
Below is a list of common forklift attachments:
Dimensioning Devices - fork truck
mounted dimensioning systems provide
dimensions for the cargo to facilitate truck
trailer space utilization and to support
warehouse automation systems. The
systems normally communicate the
dimensions via 802.11 radios. NTEP
certified dimensioning devices are
available to support commercial activities
that bill based on volume.
Sideshifter - is a hydraulic attachment
that allows the operator to move the tines
(forks) and backrest laterally. This allows
easier placement of a load without having
to reposition the truck.
Rotator - To aid the handling of skids
that may have become excessively tilted
and other specialty material handling
needs some forklifts are fitted with an
attachment that allows the tines to be
rotated. This type of attachment may also
be used for dumping containers for quick
unloading.
Fork Positioner - is a hydraulic
attachment that moves the tines (forks)
together or apart. This removes the need
for the operator to manually adjust the
tines for different sized loads.
Roll and Barrel Clamp Attachment - A
mechanical or hydraulic attachment used
to squeeze the item to be moved. It is
used for handling barrels, kegs, or paper
rolls. This type of attachment may also
have a rotate function. The rotate function
would help an operator to insert a
vertically stored paper into the horizontal
intake of a printing press for example.
Carton and Multipurpose Clamp
Attachments - are hydraulic attachments
that allow the operator to open and close
around a load, squeezing it to pick it up.
Products like cartons, boxes and bales can
be moved with this type attachment. With
these attachments in use, the forklift truck
is sometimes referred to as a clamp truck.
Pole Attachments - In some locations,
such as carpet warehouses, a long metal
pole is used instead of forks to lift carpet
rolls. Similar devices, though much larger,
are used to pick up metal coils.
Slip Sheet Attachment (Push - Pull) - is
a hydraulic attachment that reaches
forward, clamps onto a slip sheet and
draws the slip sheet onto wide and thin
metal forks for transport. The attachment
will push the slip sheet and load off the
forks for placement.
Drum Handler Attachment - is a
mechanical attachment that slides onto
the tines (forks). It usually has a spring-
loaded jaw that grips the top lip edge of a
drum for transport. Another type grabs
around the drum in a manner similar to
the roll or barrel attachments.
Telescopic Forks - are hydraulic
attachments that allow the operator to
operate in warehouse design for "double-
deep stacking", which means that two
pallet shelves are placed behind each
other without any aisle between them.
Scales -Fork truck mounted scales enable
operators to efficiently weigh the pallets
they handle without interrupting their
workflow by travelling to a platform scale.
Scales are available that provide legal-for-
trade weights for operations that involve
billing by weight. They are easily
retrofitted to the truck by hanging on the
carriage in the same manner as forks hang
on the truck.
Any attachment on a forklift will reduce its
nominal load rating, which is computed with a
stock fork carriage and forks. The actual load
rating may be significantly lower.
Chapter 2
Workshop
Workshop
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Centrifugal
Pump
Centrifugal pumps are a sub-class of dynamic
axisymmetric work-absorbing turbo machinery.
Centrifugal pumps are used to transport fluids
by the conversion of rotational kinetic energy
to the hydrodynamic energy of the fluid flow.
The rotational energy typically comes from an
engine or electric motor. In the typical case, the
fluid enters the pump impeller along or near to
the rotating axis and is accelerated by the
impeller, flowing radially outward into a
diffuser or volute chamber (casing), from
where it exits.
Common uses include water, sewage,
petroleum and petrochemical pumping. The
reverse function of the centrifugal pump is
a water turbine converting potential energy of
water pressure into mechanical rotational
energy.
How it works
Like most pumps, a centrifugal pump converts
mechanical energy from a motor to energy of a
moving fluid. A portion of the energy goes into
kinetic energy of the fluid motion, and some
into potential energy, represented by fluid
pressure (Hydraulic head) or by lifting the fluid,
against gravity, to a higher altitude.
The transfer of energy from the mechanical
rotation of the impeller to the motion and
pressure of the fluid is usually described in
terms of centrifugal force, especially in older
sources written before the modern concept
of centrifugal force as a fictitious force in a
rotating reference frame was well articulated.
The concept of centrifugal force is not actually
required to describe the action of the
centrifugal pump.
The outlet pressure is a reflection of the
pressure that applies the centripetal force that
curves the path of the water to move circularly
inside the pump. On the other hand, the
statement that the "outward force generated
within the wheel is to be understood as being
produced entirely by the medium of
centrifugal force" is best understood in terms
of centrifugal force as a fictional force in the
frame of reference of the rotating impeller; the
actual forces on the water are inward, or
centripetal, since that is the direction of force
need to make the water move in circles. This
force is supplied by a pressure gradient that is
set up by the rotation, where the pressure at
the outside, at the wall of the volute, can be
taken as a reactive centrifugal force. This was
typical of nineteenth and early twentieth
century writings, mixing the concepts of
centrifugal force in informal descriptions of
effects, such as those in the centrifugal pump.
Workshop
Haldia Refinery, IOCL | 21
Multistage centrifugal
pumps
A centrifugal pump containing two or more
impellers is called a multistage centrifugal
pump. The impellers may be mounted on the
same shaft or on different shafts.
For higher pressures at the outlet impellers can
be connected in series. For higher flow output
impellers can be connected in parallel.
A common application of the multistage
centrifugal pump is the boiler feed water
pump. For example, a 350 MW unit would
require two feed pumps in parallel. Each feed
pump is a multistage centrifugal pump
producing 150 l/s at 21 MPa.
All energy transferred to the fluid is derived
from the mechanical energy driving the
impeller. This can be measured at isentropic
compression, resulting in a slight temperature
increase (in addition to the pressure increase).
Vertical centrifugal pumps
Vertical centrifugal pumps are also referred to
as cantilever pumps. They utilize a unique shaft
and bearing support configuration that allows
the volute to hang in the sump while the
bearings are outside of the sump. This style of
pump uses no stuffing box to seal the shaft
but instead utilizes a "throttle Bushing". A
common application for this style of pump is in
a parts washer.
Froth pumps
In the mineral industry, or in the extraction of
oilsand, froth is generated to separate the rich
minerals or bitumen from the sand and clays.
Froth contains air that tends to block
conventional pumps and cause loss of prime.
Over history, industry has developed different
ways to deal with this problem. One approach
consists of using vertical pumps with a tank.
Another approach is to build special pumps
with an impeller capable of breaking the air
bubbles. In the pulp and paper industry holes
are drilled in the impeller. Air escapes to the
back of the impeller and a special expeller
discharges the air back to the suction tank. The
impeller may also feature special small vanes
between the primary vanes called split vanes
or secondary vanes. Some pumps may feature
a large eye, an inducer or recirculation of
pressurized froth from the pump discharge
back to the suction to break the bubbles.
Problems of centrifugal
pumps
These are some difficulties faced in centrifugal
pumps:
Cavitation - the net positive suction head
(NPSH) of the system is too low for the
selected pump
Wear of the Impeller - can be worsened
by suspended solids
Corrosion inside the pump caused by the
fluid properties
Overheating due to low flow
Leakage along rotating shaft
Lack of prime - centrifugal pumps must
be filled (with the fluid to be pumped) in
order to operate
Surge.
Workshop
22 | Report on Summer Training
Gear Pump
A gear pumps which is used as a meshing
gears, to pump the fluid by displacement. They
are one of the most common types
of pumps for hydraulic fluid
power applications. The Gear pumps are also
widely used in chemical installations to pump
fluid with a certain viscosity. There are two
main variations; external gear pumps which use
two external spur gears, and internal gear
pumps which use an external and an internal
spur gear. Gear pumps are positive
displacement (or fixed displacement), meaning
they pump a constant amount of fluid for each
revolution. Some gear pumps are designed to
function as either a motor or a pump.
Theory of operation
External gear pump design
for hydraulic power applications.
Internal gear (Gerotor)
pump design for automotive oil pumps.
Internal gear (Gerotor)
pump design for high viscosity fluids.
Suction and pressure ports need to interface
where the gears mesh (shown as dim gray lines
in the internal pump images). Some internal
gear pumps have an additional, crescent
shaped seal.
Pump formulas:
Flow rate in US gal/min = Fluid Density x
Pump Capacity x rpm
Power in hp = US gal/min x (lbf/in³)/1714
Generally used in:
Petrochemicals: Pure or filled bitumen,
pitch, diesel oil, crude oil, lube oil etc.
Chemicals: Sodium silicate, acids, plastics,
mixed chemicals, isocyanates etc.
Paint and ink.
Resins and adhesives.
Pulp and paper: acid, soap, lye, black
liquor, kaolin, lime, latex, sludge etc.
Food: Chocolate, cacao butter, fillers,
sugar, vegetable fats and oils, molasses,
animal food etc.
Workshop
Haldia Refinery, IOCL | 23
Screw Pump
A screw pump is a positive displacement
pump that use one or several screws to move
fluids or solids along the screw(s) axis. In its
simplest form (the Archimedes' screw pump), a
single screw rotates in a cylindrical cavity,
thereby moving the material along the screw's
spindle. This ancient construction is still used
in many low-tech applications, such as
irrigation systems and in agricultural
machinery for transporting grain and other
solids.
Development of the screw pump has led to a
variety of multi-axis technologies where
carefully crafted screws rotate in opposite
directions or remains stationary within a cavity.
The cavity can be profiled, thereby creating
cavities where the pumped material is
"trapped".
In offshore and marine installations, a three
spindle screw pump is often used to pump
high pressure viscous fluids. Three screws drive
the pumped liquid forth in a closed chamber.
As the screws rotate in opposite directions, the
pumped liquid moves along the screws
spindles.
Three-Spindle screw pumps are used for
transport of viscous fluids with lubricating
properties. They are suited for a variety of
applications such as fuel-injection, oil burners,
boosting, hydraulics, fuel, lubrication,
circulating, and feed and so on.
Compared to centrifugal pumps, positive
displacements (PD) pumps have several
advantages. The pumped fluid is moving
axially without turbulence which eliminates
foaming that would otherwise occur in viscous
fluids. They are also able to pump fluids of
higher viscosity without losing flow rate. Also,
changes in the pressure difference have little
impact on PD pumps compared to centrifugal
pumps.
Reciprocating
pumps
A reciprocating pump is a positive
plunger pump. It is often used where relatively
small quantity of liquid is to be handled and
where delivery pressure is quite large.
Reciprocating pumps can be classified based
on:
1. Sides in contact with water
Single acting Reciprocating pump
Double acting reciprocating pump
2. Numbers of cylinder used
Single cylinder pump
Two cylinder pumps
Multi-cylinder pumps
Chapter 3
Fuel Oil Block
Fuel Oil Block
Haldia Refinery, IOCL | 25
FOB (Fuel Oil Block)
It was commissioned in August 1974, originally designed for processing light Iranian Aghajari crude
but presently crudes like Arab nix (lube bearing) and Dubai crude (non – lube bearing) are processed.
The capacity has been increased from 2.5 MMPTA to 4.6 MMPTA.
Fuel oil block produces fuel oil from this block. It consist of eight subunits as given below:
Crude Distillation Unit (Unit 11 & 16)
Pre-fractionator section
Topping Section: Atmospheric Distillation Unit (ADU)
Naphtha Stabilization Unit
Naphtha Re-distillation Unit
Gas Plant (Unit 12)
De-ethaniser
Amine washing LPG
De-propaniser
Merox Unit (Unit 13)
LPG extractive merox
ATF/Gasoline sweetening merox
Naphtha Treatment Unit (Unit 14)
Naphtha Caustic Wash
Amine Absorption & Regeneration (Unit 15)
Fuel Gas Amine Absorption System
Naphtha Pre-treatment Unit (Unit 21)
Catalytic Reforming Unit (Unit 22)
Kero HDS Unit (Unit 23)
Chapter 4
DHDS
DHDS
Haldia Refinery, IOCL | 27
Unit List of DHDS Block
Chapter 5
Thermal Power Station
Thermal Power Station
Haldia Refinery, IOCL | 29
Thermal Power
Station (TPS)
TPS is one of the two main wings of power in
Haldia refinery of Indian Oil Corporation
Limited (IOCL). It is called CPP-I. The power
unit called CPP-II is gas turbine units. CPP
means captive power plant because both these
units together supplies the total power
required by the different units of the plants
and also the IOCL Township nearby, i.e. the two
generating units together fulfils the demand of
the plant only.
Capacity of TPS
There are four steam turbines with four boilers
for generating steam. BOILER I, II, III all are
made by BHEL. Each of them is capable of
delivering 125 tons of superheated steam per
hour. There is a fourth boiler (BOILER IV) with a
capacity of 150 tons of steam per hour which is
made by ABB. Four steam turbines are there
manufactured by BHEL each having a
connectivity with all the boilers. The steam
turbines act as the prime movers of four turbo
generators rotating at 3000 rpm. Three of
them (TG-1, TG-2, TG-3) have individual
capacity of 10.5 MW and the fourth one (TG4)
have a capacity of 16.5 MW. TG-4 is the most
recently installed generator and its excitation
system is ac excitation system (Brushless
exciter using rotating diode rectifier).The first
three generators are excited by DC exciter
(using two DC generators) system.
Process Flow Diagram (PFD)
The process flow diagram describes the
process of steam generation and generation of
electricity. The main components are as
follows- COOLING TOWERS: The raw water
comes from IOCL’s own water source along
with water from the nearby HFC plant. This
water is partly sent to the cooling towers in
different units for cooling and then it is used as
cooling medium in machines, heat exchangers,
compressors for cooling. TPS itself uses large
electrical motors for which cooling water is
necessary. This water also goes to others units
as service water, drinking water and fire water
after sufficient processing. For TPS water is
taken through the DM plant.
Demineralisation Plant (DM)
Here the water is treated for removing the
minerals and radicals so that they can’t create
erosion problems when heated in the boiler
drum. The pH of the water is tested and then it
is monitored nearly 7 by adding sufficient
acidic or basic materials. From here the water is
sent to a surge tank which stores the water
coming from different units and then
operating on a level switch and PLC system
sends the water to de-aerator by the help of a
pump.
De-aerator
One of the feed water heaters is a
contact-type open heater, known as de-
aerator, others being closed heaters. It is
used for the purpose of de-aerating the
feed water.
The presence of dissolved gases like
oxygen and carbon dioxide in water makes
the water corrosive, as they react with the
metal to form iron oxide. The solubility of
these gases in water decreases with
increase in temperature and becomes zero
at the boiling or saturation temperature.
These gases are removed in the de-aerator,
where feed water is heated to saturation
temperature by the steam extracted by the
turbine. Feed water after passing through a
heat exchanger is sprayed from the top so
as to expose large surface area, and the
bled steam from the turbine is fed from
the bottom. By contact the steam
condenses and the feed water is heated to
Thermal Power Station
30 | Report on Summer Training
the saturation temperature. Dissolved
oxygen and carbon dioxide gases get
released from the water and leave along
with some vapour, which is condensed back
to the vent condenser, and the gases are
vented out.
To neutralize the effect of the residual
dissolved oxygen and carbon dioxide gases
in water, sodium sulphite or hydrazine is
injected in suitable calculated doses into
the feed water at the suction of the boiler
feed pump.
The de-aerator is usually placed near the
middle of the feed water system so that
the total pressure difference between the
condenser and the boiler is shared
equitably between the condenser pump
and the boiler feed pump. The feed water
heaters before the de-aerator are open are
often termed as high pressure heaters and
those after the de-aerator are termed as
low pressure heaters.
There are two de-aerator that supply water
to the four boilers of the thermal power
station.
Figure: De-aerator
Thermal Power Station
Haldia Refinery, IOCL | 31
Schematic Layout (TPS)
Thermal Power Station
32 | Report on Summer Training
Boiler
In TPS 4 boiler are used for steam generation.
A steam generator generates steam at a
desired rate at a desired pressure and
temperature by burning fuel at its furnace. A
steam generator is a complex integration of
furnace, superheater, economizer, reheater,
boiler or evaporator, and air preheater along
with various auxiliary such as ash handling
equipment, pulverizers, burners, fans, stokers,
dust collectors and precipitators. The boiler is
that part of steam generator where phase
change occurs from liquid to vapour essentially
at constant pressure and temperature.
However the term “boiler” is traditionally used
to mean the whole steam generator.
The steam coming out from the boiler is
treated again to maintain its pressure (61
kg/cm2) and temperature (450oc) and made
oxygen free. This is called high pressure
superheated steam which is sent to turbine
generator for generating electricity. This is also
converted to medium pressure (VM) and low
pressure steam (VB) for other uses as follows:
Uses of Steam:
VH Steam: used in turbine generator as
well as in burner
VM Steam: in heat exchanger in different
units
VB Steam: used for cleaning oil
Burner Unit
Here furnace oil is burnt in presence of air to
produce hot flue gas at very high temperature.
Every boiler has six burner units. Furnace oil is
burnt and the hot gas is released in the boiler.
The relatively cold flue gas after going through
the economizer zone is sent out to stack and
released in the atmosphere.
Air Supply
An air supply unit is kept to supply air to the
compressor as well as drier to produce
compressed dry air supply for pneumatic
instruments.
Thermal Power Station
Haldia Refinery, IOCL | 33
Steam Turbine
The TPS or CPP-I has four steam turbines. Each
turbine has two section, namely HP and LP
section. The inlet blades (at HP section) are
impulse type and the outlet blades are reaction
(at LP section) type. The steam produced in the
boiler is fed to the inlet section at very high
pressure (60-62 Kg/Sq. cm) which rotates the
inlet blades. As the steam moves from HP to LP
region, its temperature decreases and the low
pressure steam (14 Kg/Sq. cm) is extracted
from a set point determined previously. The
exhaust steam is fed to the condenser.
Cooling Tower
A cooling tower is a semi enclosed device for
evaporative cooling of cooling water coming
out from the condenser with the help of
unsaturated water. So, in this process, proper
mixing with hot water droplet and air will take
place. There will be both heat and mass
transfer for getting more efficient cooling in
the cooling tower. Usually the structure of
cooling tower may be done by wood, concrete,
steel etc. Corrugated surfaces or perforated
trays can be provided inside the tower for
uniform distribution of water droplets and
better atomization of the water inside the
tower. The air is allowed to flow from the
bottom of the tower or perpendicular to the
direction of the water flow (in crossed flow
cooling tower) and the exhausts is allowed to
go out to the atmosphere after effective
cooling.
Gas Turbine (GT)
Gas turbines (GT) are another unit for
generation of power except TPS in IOCL Haldia
refinery.
It has three gas turbines each with a capacity
of 25-30MW. They generate power and they
are synchronized with the bus bar which
connects them to the TPS. From TPS this power
is distributed. As it has a huge capacity, it is
very important to maintain it so that power
requirement is always fulfilled.
Thermal Power Station
34 | Report on Summer Training
All three gas turbines are installed by BHEL.
The control unit is also supplied by BHEL.
How do gas turbines work?
Gas turbine engines are, theoretically,
extremely simple.
They have 3 parts:
A compressor to compress the incoming air to
high pressure.
A combustion area to burn the fuel and
produce high pressure, high velocity gas. A
turbine to extract the energy from the high
pressure, high velocity gas flowing from the
combustion chamber.
Just opposite to the working principle of TPS.
In TPS the fuel and air mixture with proper
ratio is burned to produce flue gas which is
then used to heat the water to make
superheated steam. This steam is then used to
rotate the turbine from which power is
produced.
Here the high pressure and high temperature
flue gas is directly applied to the prime mover
from where the electricity is produced. After
that this high temperature flue gas is used to
heat water to produce steam so that the
system becomes more economic. So when
ever in the plant the gas turbine is on duty, the
corresponding steam producing unit is also
activated so that the efficiency of the whole
process increases.
In this engine air is sucked in from the right by
the compressor. The compressor is basically a
cone-shaped cylinder with small fan blades
attached in rows (8 rows of blades are
represented here). Assuming the light blue
represents air at normal air pressure, then as
the air is forced through the compression
stage its pressure and velocity rise significantly.
In some engines the pressure of the air can rise
by a factor of 30. The high pressure air
produced by the compressor is shown in dark
blue.
This high-pressure air then enters the
combustion area, where a ring of fuel injectors
injects a steady stream of fuel.
At the left of the engine is the turbine section.
In this figure there are two sets of turbines. The
first set directly drives the compressor. The
turbines, the shaft and the compressor all turn
as a single unit:
At the far left is a final turbine stage, shown
here with a single set of vanes. It drives the
output shaft. This final turbine stage and the
output shaft are a completely stand-alone,
freewheeling unit. They spin freely without any
connection to the rest of the engine. The
exhaust is sent to the heat exchanger unit
where the water is heated to produce steam
and then the gas is let out through chimney.
Thermal Power Station
Haldia Refinery, IOCL | 35
Specifications Boiler Feed Pump Capacity: 145 m3/hr.
Lube oil: Sp. gr. =57
Discharge Pressure: 80-85 Kg/cm2
Service B Feed Water
Motor Data Capacity: 460 KW
Speed: 2980 rpm
FD Fans
Type: Radial single inlet and single width
Medium: Air
Designed rating: 40.8 m3/sec
Fan Speed: 740 rpm
Air Drier
A compressed air dryer is a device for
removing water vapour from compressed air.
Compressed air dryers are commonly found in
a wide range of industrial and commercial
facilities. The process of air compression
concentrates atmospheric contaminants,
including water vapour. This raises the dew
point of the compressed air relative to free
atmospheric air and leads to condensation
within pipes as the compressed air cools
downstream of the compressor.
Excessive water in compressed air, in either the
liquid or vapour phase, can cause a variety of
operational problems for users of compressed
air. These include freezing of outdoor air lines,
corrosion in piping and equipment,
malfunctioning of pneumatic process control
instruments, fouling of processes and
products, and more.
There are various types of compressed air
dryers. Their performance characteristics are
typically defined by the dew point.
Capacity: 2400nm3/hr.
Moist air inlet: RH=100% Pressure=8 Kg/cm2
(normal), 6.5 Kg/cm2 (minimum)
Temperature: 40oc
Dry Air outlet
Type of Desiccant: Activated Alumina
Pressure drop across the drier: 0.5 Kg/cm2
(Maximum)
Adsorption Towers: Design Pressure=12
Kg/cm2
Pre-filter and After-filter: Filter element = Poly-
propelene, Design Pressure: 12 Kg/cm2
Cooler: water flow: 22.825 m3/hr.
Water Pressure: 4Kg/cm2
Inlet water temperature: 33oc
Outlet water temperature: 37oc
Heater: Power rating: 81KW (56.7 KW and 24.3
KW)
Chapter 6
Lube Oil Boiler
Lube Oil Boiler
Haldia Refinery, IOCL | 37
LOB (Lube Oil Boiler)
In lube oil block, the reduced crude oil from the Atmospheric Distillation Unit (ADU) is processed to
produce lube base stock, slack wax, transfer oil feed stock (TOFS), etc. LOB contains the following 8
units:
Main feed: RCO
Unit 31: Vacuum Distillation Unit
RCO (400oc)
a) Gas oil
b) Spindle oil
c) Light oil
d) Intermediate oil
e) Heavy oil
f) Short residue (360oc)
Unit 32: Propane De-asphalting Unit
Short Residue - treated with propane (225oc) -
DAO (De asphalt oil) + Asphalt (Bitumen)
Unit 33: Furfural Extraction Unit
Feed (L.O/I.O/H.O/DAO) (by furfural
extraction)(225oc)Raffinate + Extract
Raffinate feed to Unit #4 (De-waxing Unit)
In/Hn/Bn/de-waxed lube oil
Unit 35: Hydro finishing Unit
Feed - Lube Oil (de-waxed) - Heated in
catalytic bed at 250oC - Finished lube oil
Unit 37: Visbreaker Unit
Asphalt + SR (60:40) (heated --- 4500c)
a) Gasoline (mixed in petrol)
b) Gas oil
c) VB tar (FO)
Unit 38: NMP Unit
I.O/H.O/DAO - treatment with NMP solution
Unit 39: Microcrystalline Wax
After de waxing in unit 34 Residue wax is
treated in this unit by hydrogen to produce
Micro-crystalline wax.
Unit 84: Catalytic De-waxing Unit
Raffinate (from 33 and 38) + wax treatment
in catalystic bed with hydrogen to remove
sulphur/ nitrogen/ H2S/ NH3
Temperature - 310oc – 380oc
Produced de-waxed lube oil
Lube Oil Boiler
38 | Report on Summer Training
Chapter 7
Offsite
Offsite
40 | Report on Summer Training
Offsite
Drum loading: Drums are loaded with bitumen.
All the operations are automated. However in
case of any failure or emergency operations
are done manually
Truck loading: Trucks are loaded with 19 tons
aviation oils. Again all the operations are
automated.
Barge loading: Ships are loaded and unloaded
manually.
LPG filling: LPG is filled into the storage tank
and this mechanism is achieved by
automation.
Cathodic Protection
External protection of Mounded LPG storage
bullets is an electrochemical phenomenon. The
control of this common process can be
achieved by employing CATHODIC
PROTECTION system. The state of art cathodic
system can be implemented to distribute
uniform current over the entire surface to be
protected to achieve uniform corrosion
protective potentials.
Types
Permanent Impressed Current type of cathodic
protection system using continuous anode
system is to be implemented for protecting
external surface area of bullet against
corrosion.
Protective Current Density
Protective current density recommended by
LURGI.
General specification and BIS 8062-Part1
(1976) are as follows:
Bare steel 25mA/m2
Painted steel 2.5mA/m2
Protective current density of 25mA/m2 of bare
steel exposed to sand shall be adequate to
achieve desired protection level at an
operating temperature of 5 – 46 degree
Celsius.
Protection Criteria
The protected bullet to soil potential test has
been established as a standard measure
technique for evaluation of corrosion
protective potential. The OFF potential window
considered is -0.85V (OFF) to -1.15V (OFF)
measured with respect to Copper-Copper
Sulphate reference electrode at an instant by
interrupting the protective current and
eliminating circuit IR drop.
Types of Surface
Coating/Painting
External surface of bullet is Polyurethane
coated and buried in mound of sand layer.
Chapter 8
Once-through Hydro
Cracking Unit
Once-through Hydro Cracking Unit
42 | Report on Summer Training
Once-through
Hydro Cracking
Unit
It consists of Hydrogen Generation Unit, Once–
through Hydrocracker Unit, Sulphur Recovery
Unit and Nitrogen Unit .Initially installed with a
2.5 MMTPA crude processing capacity with
designed LOBS
It has a production capacity of 200,000 MTPA,
the Refinery has subsequently augmented its
capacity to process 6.0 MMTPA crude. The
capacity of the refinery is being augmented to
7.5 MMTPA through revamp of Crude
distillation unit in the year 2009-10.
Since commissioning of the Paradip-Haldia
Crude oil Pipeline (PHCPL) in Jan'09, the
refinery started receiving crude oil from
Paradip port and receiving of crude by oil
Tankers through oil jetties has come down
resulting in optimization of transportation
costs of crude oil. The Refinery has facilities for
storage of crude oil and finished products
produced by the refinery.
Hydro Cracking Unit is designed for 1.2
MMT/year (165.6 m³/hr, 25,000BPSD). The
objective of the Hydro Cracking Unit is to
produce middle distillate fuel of superior
quality. The unit is designed to process two
different types of feed i.e. Arab Mix HVGO,
Bombay High HVGO. All the H2S will be
removed by absorbing in DEA.
Process Description
Heavier Hydro-Carbon molecules are mixed
with Hydrogen and the mixture is subjected to
severe operating conditions of Temp. (380 -
400 oC) and pressure (165 – 185 kg/cm2) to get
Lighter Hydro-Carbons like LPG, MS & HSD
components. Strict operating conditions are
maintained to get on-specs. products. All
products are of Superior quality w.r.t. Sulphur
content.
The Hydrocracker Unit consists of
four principle sections:
Make-Up Gas Hydrogen Compression
Reactor Section
Fractionation Section
Light Ends Recovery Section
Reactor Feed System
Fresh feed to the Hydrocracker consists of a
blend of Arab Mix and Bombay High VGO. The
feed control system allows the operator to
control the ratio of Arab Mix and Bombay High
VGOs in order to set the relative rates of each
.The preheated and filtered oil feed is
combined with a preheated mixture of make-
up hydrogen from the make-up hydrogen
compression section and hydrogen-rich recycle
gas from the recycle gas compressor in a gas-
to-oil ratio of 845 Nm3/m3.The reactor system
contains one reaction stage consisting of two
reactors in series in a single high-pressure
loop. The lead and main reactors contain hydro
treating and hydro cracking catalyst (Si/Al with
Ni-Co-Fe) for denitrification, desulphurization,
and conversion of the raw feed to products
.The reactor effluent is initially cooled by heat
exchange with the VGO feed and then by heat
exchange with recycle gas and with the
product fractionators feed. The effluent is then
used to generate medium pressure [12.0
kg/cm2 (g)] steam.
Fractionation Section
The fractionation section consisting of the
fractionators, side cut strippers, and heat
exchange equipment is designed to separate
conversion products from unconverted feed.
The reaction products recovered from the
column are Sour Gas (Off gas), Unstable Light
Naphtha, Heavy Naphtha, Kerosene, Diesel and
FCC Feed. The fractionator off-gas and
Once-through Hydro Cracking Unit
Haldia Refinery, IOCL | 43
unstable light naphtha are sent to the light
ends recovery section for recovery of LPG and
light naphtha product.
De-Ethaniser
The de-ethaniser remove light ends (C2), H2S,
and water from the light naphtha and LPG.
Feed enters the top of the column. The feed to
the de-ethaniser comes from the combined
liquid stream leaving the de-ethaniser reflux
drum and is pumped to the top of the de-
ethaniser.
Hydrogen Generation Unit
The Unit is designed to process Straight Run
Naphtha or Natural Gas to hydrogen that will
cater to the needs of the new DHDT-MSQ and
other units .The process involved for converting the
Naphtha to hydrogen is steam reforming. Process
licensor for HGU is HTAS, Denmark. The plant
is divided into 3 sections:
Desulphurization
Reforming
CO-Conversion
Sulphur Recovery Unit
The unit consists of three identical units A, B
and C. One of them is kept standby. The
process design is in accordance with common
practice to recover elemental sulphur known as
the Clause process, which is further improved
by Super Clause process. Each unit consists of
a thermal stage, in which H2S is partially burnt
with air, followed by two catalytic stages. A
catalytic incinerator for incineration of all gases
has been incorporated in order to prevent
pollution of the atmosphere.
The primary function of the waste heat boiler
is to remove the major portion of heat
involved in the combustion chamber. The
secondary function of waste heat boiler is to
condense the sulphur, which is drained to a
sulphur pit. At this stage 60% of the sulphur
present in the sour gas feed is removed. The
third function of the waste heat boiler is to
utilize the heat liberated there to produce LP
steam (4kg/cm2).The process gas leaving the
waste heat boiler still contains a considerable
part of H2S and SO2. Therefore, the essential
function of the following equipment is to shift
the equilibrium by adopting a low reactor
temperature thus removing the sulphur as
soon as it is formed. Conversion to sulphur is
reached by a catalytic process in two
subsequent reactors containing a special
synthetic alumina catalyst .Before entering the
first reactor, the process gas flow is heated to
an optimum temperature by means of a line
burner, with mixing chamber, in order to
achieve a high conversion. In the line burner
mixing chamber the process gas is mixed with
the hot flue gas obtained by burning fuel gas
with air .In the first reactor the reaction
between the H2S and SO2 recommences until
equilibrium is reached. The effluent gas from
the first reactor passes to the first sulphur
condenser where at this stage approximately
29% of the sulphur present in the sour gas
feed is condensed and drained to the sulphur
pit. The total sulphur recovery after the first
reactor stage is 89% of the sulphur present in
the sour gas feed. In order to achieve a figure
of 94% sulphur recovery the sour gas is
subjected to one more stage.
Feed
The hydrogen generation unit can be fed
either by naphtha or natural gas. The naphtha
feed is pressurized to about 35 Kg/cm2 by one
of the naphtha feed pumps and sent to the
desulphurization section. The pressurized feed
is mixed with recycle hydrogen from the
hydrogen header. The liquid naphtha is
evaporated to one of the naphtha feed
vaporizers. The hydrocarbon feed is heated to
380°-400°C by heat exchange with
superheated steam in the naphtha feed pre-
heater.
Once-through Hydro Cracking Unit
44 | Report on Summer Training
OHCU Layout
Components used in OHCU
1. RGC (Recyle Gas Compressor)
2. MUG (Make Up Gas Compressor)
3. VGO (Vacuum Gas Oil)
Layout
Once-through Hydro Cracking Unit
Haldia Refinery, IOCL | 45
Figure: OHCU Layout
Findings
Findings
Haldia Refinery, IOCL | 47
For any academic discipline, especially practical
streams like engineering field knowledge
should go hand-in-hand with theoretical
knowledge. In university classes our quest for
knowledge is satiated theoretically. Exposure to
real field knowledge is obtained during such
vocational training. We have learnt a lot about
pumps, turbines, compressors, valves and
other mechanical equipment. We might have
thoroughly learnt the theory behind these but
practical knowledge about these were mostly
limited to samples at laboratory. At Indian Oil
Corporation Limited we actually saw the
equipment used in industry. Though the
underlying principle remains same but there
are differences as far as practical designs are
considered. We also got to know additionally
about other features not taught or known
earlier. This has helped to clarify our theoretical
knowledge a lot. Apart from knowing about
matters restricted to our own discipline we also
got to know some other things. Indian Oil
Corporation Limited is mainly a chemical
industry. So we had to go through concepts
like Cathodic Protection, which we might not
have necessarily read within our curriculum.
There is much difference between perception
and realization. This is one very important
thing we learnt during the training period.
While designing machines on paper or while
studying them from books we most often
condone some practical aspects like economy,
availability, etc. Here, we got to know about
some of these practical constraints. Most
engineering students will join some industry
either in their final year or a few years later.
Such vocational trainings, apart from boosting
our knowledge, for the first time, give us some
practical insight into corporate sector. This is
highly needed. Everyone knows that to
succeed in industry just theory is not enough.
In fact, in industry we not only deal with
machines but also with other personnel, who
may be subordinates, colleagues or superiors.
Managing personnel, coordinating,
maintaining harmony at workplace, discipline,
helping others and at the same time being
cautious about one’s own interests- these are
some very important aspects of corporate life.
Such vocational trainings give us some feeling
about the industry environment. The close
interactions with guides, many of whom are
just some year ’s seniors to us have also helped
us a lot. It is they who, apart from throwing
light on equipment, have also shown the
different aspects and constraints of corporate
life. Discussions with them have not only
satisfied our enquiries about machines and
processes but also enlightened about many
other extra-curricular concepts which are also
important parameters in industry. Thus our
training in Indian Oil Corporation Limited has
been an enlightening one imparting
knowledge on different aspects encompassing
theory, practical concepts and other above-
mentioned concerns. In short, the experience
has been thrilling, exciting and enriching one.
Department of Mechanical Engineering,National Institute of Technology Durgapur,Mahatma Gandhi Avenue, Durgapur 713209.