oil -all about it

7/28/2019 Oil -All About It

1/22

Multi-crore pilferage in Mathura refinery

LUCKNOW: Villagers in Mathura have helped unearth a racket through which

crores of litres ofcrude oil are estimated to have been siphoned off from the

main pipeline ofIndian Oil Corporation Ltd (IOCL) between Salayan in

Gujarat and the Mathura refinery. Police have unearthed a 400-metre pipelineof two inches in diameter through which the crude oil was being stolen from

the underground main line probably for the past three years.

SSP Mathura Pradeep Kumar Yadav said criminal elements had hacked

the main Salayan-Mathura pipeline near Sonoth village, about 45km from

Mathura city. "They had attached a valve to the main pipeline running

underground. This valve was connected to a 2 inch diameter pipe through

which the pilferage was being delivered 400 metres away from the pipeline,"

Yadav told TOI.

IG Agra zone Ashutosh Pandey said the state government had been

informed about the theft that is estimated to have led to losses worthhundreds of crores of rupees. "We are trying to establish the specifics like the

manner in which this pilferage was done without being detected by the local

police or the authorities at the refinery," Pandey said.

As per reports, people from Sonoth informed a senior police officer about

a shady business that had been operating from the village for the past three

years. The villagers told the officer that many oil tankers visited a makeshift

structure situated in the middle of a farm on the village outskirts every night,

and by dawn the entire premises would be deserted. On the basis of this

complaint, the police conducted an inquiry, which discovered the pilferage

racket. As per the initial reports, police have registered a case against oneMukesh Thakur and his nephew Subhash, who are believed to be the kingpin

of the racket. Raids were underway to arrest the two. The local police is

baffled about it since IOC has an internal mechanism to detect pilferage by

detecting change in flow pressure.

The leakage could not be detected since line flow rate was very low.

Normally computer detects line flow rate if it is beyond 3 per cent, Haq said.

"I am confident that none of our staff is directly or indirectly involved," he

said. However to prevent future thefts of crude, a meeting of high officials

would be called and ways would be found, he said.

ENGLISH FROM THIS TOPIC

1. unearth /nrTH/ Verb

Find (something) in the ground by digging.

Discover (something hidden, lost, or kept secret) by investigation or

searching: "unearth the truth".


2/22

Synonyms

detect - discover - disinter - excavate - uncover

2. siphon off something /siphon something off

to take something that was intended for someone or something else The

dictator and his close friends siphoned off up to 20 percent of the annual

budget. The donated food was mostly siphoned off and sold, while the needy

got almost nothing.

3. hack 1 (hk) v.

1. To cut or chop with repeated and irregular blows: hacked down the

saplings.

2. To break up the surface of (soil).

3.a. Informal To alter (a computer program): hacked her text editor to read

HTML.

b. To gain access to (a computer file or network) illegally or without

authorization: hacked the firm's personnel database.

4. Slang To cut or mutilate as if by hacking: hacked millions off the budget.

5. Slang To cope with successfully; manage: couldn't hack a second job.

hack 2 (hk) n.

1. A horse used for riding or driving; a hackney.

2. A worn-out horse for hire; a jade.

4.pilferage (n )

1. the act or practice of stealing small quantities or articles

2. the amount so stolen

Noun 1. pilferage - the act of stealing small amounts or small articles

larceny, stealing, theft, thievery, thieving

5.dawn (dn) n.

1. The time each morning at which daylight first begins.

2. A first appearance; a beginning: the dawn of history. See Synonyms at

beginning.


3/22

intr.v. dawned, dawning, dawns

1. To begin to become light in the morning.

2. To begin to appear or develop; emerge.

3. To begin to be perceived or understood: Realization of the danger soondawned on us.

6) makeshift (adj)

serving as a temporary or expedient means, esp during an emergency

n something serving in this capacity

7)baffle (bfl) tr.v. baffled, baffling, baffles

1. To frustrate or check (a person) as by confusing or perplexing; stymie.

2. To impede the force or movement of.

n.

1. A usually static device that regulates the flow of a fluid or light.

2. A partition that prevents interference between sound waves in a

loudspeaker.

8) premise (prms) n. also premiss (prms)

1. A proposition upon which an argument is based or from which a conclusion

is drawn.

2. Logic

a. One of the propositions in a deductive argument.

b. Either the major or the minor proposition of a syllogism, from which the

conclusion is drawn.

3. premises Law The preliminary or explanatory statements or facts of a

document, as in a deed.

4. premises

a. Land and the buildings on it.

b. A building or part of a building.


4/22

9) mechanism (mk-nzm) n.

1.a. A machine or mechanical appliance.

b. The arrangement of connected parts in a machine.

2. A system of parts that operate or interact like those of a machine: themechanism of the solar system.

3. An instrument or a process, physical or mental, by which something is

done or comes into being: "The mechanism of oral learning is largely that of

continuous repetition" (T.G.E. Powell).

4. A habitual manner of acting to achieve an end.

5. Biology The involuntary and consistent response of an organism to a given

stimulus.

6. Psychology A usually unconscious mental and emotional pattern that

shapes behavior in a given situation or environment: a defense mechanism.

7. The sequence of steps in a chemical reaction.

8. Philosophy The doctrine that all natural phenomena are explicable by

material causes and mechanical principles.

EXTRA KNOWLEDGE ABOUT THIS ARTICLE

An oil is any neutral, nonpolar chemical substance, that is a viscous liquid at

ambient temperatures, and is immiscible( not soluble) with water but solublein alcohols or ethers. Oils have a high carbon and hydrogen content and are

usually flammable and slippery.

####flammable liquid as one with a flash point(The flash point of a volatile

material is the lowest temperature at which it can vaporize to form an

ignitable mixture in air. Measuring a flash point requires an ignition source. At

the flash point, the vapor may cease to burn when the source of ignition is

removed.) below 100 degrees Fahrenheit. Less-flammable liquids (with a

flashpoint between 100 degrees and 200 degrees Fahrenheit) are defined as

combustible liquids. .These categories are further subdivided, depending onthe liquid's flash point and boiling point.

Note :The autoignition temperature or kindling point of a substance is the

lowest temperature at which it will spontaneously ignite in a normal

atmosphere without an external source of ignition, such as a flame or spark.It

depends on the concentrationof oxygen around.


5/22

Normal room temperatue ranges b/w =20 C (68 F or 293 K) to 25

C (77 F or 298 K)

Class IA flammable liquids have a flash point below 73 F (the upper end of

the common range of room temperature) and a boiling point below 100 F

---- DIMETHYL ETHER

Class IB flammable liquids have a flash point below 73 F (-40degree C)and a

boiling point greater than or equal to 100 F-------GASOLINE(PETROL)

Class IC flammable liquids have a flash point greater than or equal to 73 F

and below 100 F

Class II combustible liquids have a flash point greater than or equal to 100 F

and below 140 F ----- DIESEL & JET FUEL

Class IIIA combustible liquids have a flash point greater than or equal to 140

F and below 200 F----- KEROSENE

Class IIIB combustible liquids have a flash point greater than or equal to 200

F------BIOFUEL & VEGETABLE OIL

Oils may be------- animal, vegetable, or petrochemical(mineral) in

origin,

------- volatile( volatility is the tendency of a substance to

vaporize. Volatility is

directly related to a substance's vapor pressure. At a given

temperature, a substance with higher vaporpressure vaporizes more readily

than a substance with a lower vapor

pressure)

These are volatile at room temperature &

are usually obtained by distillation.When

evaporate do not leave any spot.

or non-volatile (Non volatile at room temp & can be

obtained by special extraction process.

These leave spot after evaporation.

Types of oil according to origin

1)Organic oils

Organic oils are produced in remarkable diversity by plants, animals, and

other organisms through natural metabolic processes. Lipid is the scientific


6/22

term for the fatty acids, steroids and similar chemicals often found in the oils

produced by living things, while oil refers to an overall mixture of chemicals.

Organic oils may also contain chemicals other than lipids, including proteins,

waxes and alkaloids.

Lipids can be classified by the way that they are made by an organism, theirchemical structure and their limited solubility in water compared to oils. They

have a high carbon and hydrogen content and are considerably lacking in

oxygen compared to other organic compounds and minerals

Plant oils or vegetable oils are oils derived from plant sources, as opposed to

animal fats or petroleum. There are three primary types of plant oil, differing

both the means of extracting the relevant parts of the plant, and in the

nature of the resulting oil:

Vegetable fats and oils were historically extracted by putting part of the plant

under pressure, squeezing out the oil. eg mustard oil , date palm oil , canolaoil , olive oil ,linseed oil ,

Macerated oils consist of a base oil to which parts of plants are added. eg

herbs and flowers

Essential oils are composed of volatile aromatic compounds, extracted from

plants by distillation. Essential oils are not oils but volatile aromatic

compounds that are used in flavors, fragrances, and in aroma therapy for

health purposes. Essential oils are usually extracted by distillation.

Oil source World consumption

(million metric tons) Notes

Palm 41.31 The most widely produced tropical oil, also used to make biofuel

Soybean 41.28 Accounts for about half of worldwide edible oil production

Rapeseed 18.24 One of the most widely used cooking oils, canola is a

variety (cultivar) of rapeseed

Sunflower seed 9.91 A common cooking oil, also used to make biodiesel

Peanut 4.82 Mild-flavored cooking oil

Cottonseed 4.99 A major food oil, often used in industrial food processing

Palm kernel 4.85 From the seed of the African palm tree


7/22

Coconut 3.48 Used in soaps and cooking

Olive 2.84 Used in cooking, cosmetics, soaps and as a fuel for traditional oil

lamps

Note that these figures include industrial and animal feed use. The majority

of European rapeseed oil production is used to produce biodiesel, or used

directly as fuel in diesel cars which may require modification to heat the oil to

reduce its higher viscosity. The suitability of the fuel should come as little

surprise, as Rudolf Diesel originally designed his engine to run on peanut oil.

Other significant triglyceride oils include:

Corn oil, one of the most common cooking oils. As of 2006 the US produced

about 1.09 million metric tons [17] of corn oil, which is used for cooking oil,

salad dressing, margarine, mayonnaise, prepared goods like spaghetti sauce

and baking mixes, and to fry prepared foods like potato chips and French

fries.

Grape seed oil, used in cooking and cosmetics

Hazelnut and other nut oils

Linseed oil, from flax seeds

Rice bran oil, from rice grains

Safflower oil, a flavorless and colorless cooking oil

Sesame oil, used as a cooking oil, and as a massage oil, particularly in India

To produce vegetable oils, the oil first needs to be removed from the oil-

bearing plant components, typically seeds. This can be done via mechanical

extraction using an oil mill or chemical extraction using a solvent. The

extracted oil can then be purified and, if required, refined or chemically

altered.

Mechanical extraction

Oils can also be removed via mechanical extraction, termed "crushing" or

"pressing." This method is typically used to produce the more traditional oils

(e.g., olive, coconut etc.), and it is preferred by most "health-food" customers

in the United States and in Europe.[citation needed] There are several

different types of mechanical extraction.[11] Expeller-pressing extraction is

common, though the screw press, ram press, and Ghani (powered mortar and

pestle) are also used. Oil seed presses are commonly used in developing


8/22

countries, among people for whom other extraction methods would be

prohibitively expensive; the Ghani is primarily used in India.[12] The amount

of oil extracted using these methods varies widely, as shown in the following

table for extracting mowrah butter in India:[13]

Method Percentage extracted

Ghani[14] 2030%

Expellers 3437%

Solvent 4043%

Solvent extraction

The processing vegetable oil in commercial applications is commonly done by

chemical extraction, using solvent extracts, which produces higher yields and

is quicker and less expensive. The most common solvent is petroleum-derived hexane. This technique is used for most of the "newer" industrial oils

such as soybean and corn oils.

Supercritical carbon dioxide can be used as a non-toxic alternative to other

solvents.[15]

Hydrogenation

Oils may be partially hydrogenated to produce various ingredient oils. Lightly

hydrogenated oils have very similar physical characteristics to regular soy oil,

but are more resistant to becoming rancid. Margarine oils need to be mostly

solid at 32 C (90 F) so that the margarine does not melt in warm rooms, yetit needs to be completely liquid at 37 C (98 F), so that it doesn't leave a

"lardy" taste in the mouth.

Hardening vegetable oil is done by raising a blend of vegetable oil and a

catalyst in near-vacuum to very high temperatures, and introducing

hydrogen. This causes the carbon atoms of the oil to break double-bonds with

other carbons, each carbon forming a new single-bond with a hydrogen atom.

Adding these hydrogen atoms to the oil makes it more solid, raises the smoke

point, and makes the oil more stable.

Hydrogenated vegetable oils differ in two major ways from other oils whichare equally saturated. During hydrogenation, it is easier for hydrogen to come

into contact with the fatty acids on the end of the triglyceride, and less easy

for them to come into contact with the center fatty acid. This makes the

resulting fat more brittle than a tropical oil; soy margarines are less

"spreadable"[compared to?]. The other difference is that trans fatty acids

(often called trans fat) are formed in the hydrogenation reactor, and may


9/22

amount to as much as 40 percent by weight of a partially hydrogenated oil.

Hydrogenated oils, especially partially hydrogenated oils with their higher

amounts of trans fatty acids are increasingly thought to be unhealthy.

Sparging

In the processing of edible oils, the oil is heated under vacuum to near the

smoke point, and water is introduced at the bottom of the oil. The water

immediately is converted to steam, which bubbles through the oil, carrying

with it any chemicals which are water-soluble. The steam sparging removes

impurities that can impart unwanted flavors and odors to the oil.

Animal fats and oils are lipid materials derived from animals. Physically, oils

are liquid at room temperature, and fats are solid. Chemically, both fats and

oils are composed of triglycerides. Although many animal parts and

secretions may yield oil, in commercial practice, oil is extracted primarily

from rendered tissue fats obtained from livestock animals like pigs, chickensand cows. Dairy products also yield popular animal fat and oil products such

as cheese, butter, and milk.

Fish mainly cod , shark and mammal whale are great source of animal oil.

Flesh and animal fat have a melting temperature of 184 C, a boiling point of

around 200 C and an ignition point of 280 C where it will burst into flames

without spark. Certain substances such as goose fat produce a higher smoke

point than other animal fats, but are still lower than many vegetable oils such

as olive or avocado.

Mineral oils

Crude oil, or petroleum, and its refined components, collectively termed

petrochemicals, are crucial resources in the modern economy. Crude oil

originates from ancient fossilized organic materials, such as zooplankton and

algae, which geochemical processes convert into oil. The name is a

misnomer, in that minerals are not the source of the oil - ancient plants and

animals are. Mineral oil is organic. However, it is classified as "mineral oil"

instead of as "organic oil" because its organic origin is remote (and was

unknown at the time of its discovery), and because it is obtained in the

vicinity of rocks, underground traps, and sands. Mineral oil also refers toseveral specific distillates of crude oil. Petroleum is a naturally occurring

flammable liquid consisting of a complex mixture of hydrocarbons of various

molecular weights and other liquid organic compounds, that are found in

geologic formations beneath the Earth's surface. The name Petroleum covers

both naturally occurring unprocessed crude oils and petroleum products that

are made up of refined crude oil. A fossil fuel, it is formed when large

quantities of dead organisms, usually zooplankton and algae, are buried


10/22

underneath sedimentary rock and undergo intense heat and pressure.

Petroleum is recovered mostly through oil drilling. This comes after the

studies of structural geology (at the reservoir scale), sedimentary basin

analysis, reservoir characterization (mainly in terms of porosity and

permeable structuresIt is refined and separated, most easily by boiling point,into a large number of consumer products, from petrol (or gasoline) and

kerosene to asphalt and chemical reagents used to make plastics and

pharmaceuticals.[6] Petroleum is used in manufacturing a wide variety of

materials,[7] and it is estimated that the world consumes about 88 million

barrels each day.

Unit of volume for crude oil and petroleum products. One barrel equals 42 US

gallons or 35 UK (imperial) gallons, or approximately 159 liters or 9,702 cubic

inches (5.6 cubic feet); 6.29 barrels equal one cubic meter and (on average)

7.33 barrels weigh one metric ton (1000 kilograms). One barrel of crude

equals 5604 cubic-feet of natural gas, 1.45 barrels of liquefied natural gas(LNG), or about one barrel of gas oil.

Octane rating or octane number is a standard measure of the performance of

a motor or aviation fuel. The higher the octane number, the more

compression the fuel can withstand before detonating. In broad terms, fuels

with a higher octane rating are used in high-compression engines that

generally have higher performance. In contrast, fuels with lower octane

numbers (but higher cetane numbers) are ideal for diesel engines. Use of

gasoline with less octane numbers may lead to the problem of engine

knocking.

Knocking (also called knock, detonation, spark knock, pinging or pinking) in

spark-ignition internal combustion engines occurs when combustion of the

air/fuel mixture in the cylinder starts off correctly in response to ignition by

the spark plug, but one or more pockets of air/fuel mixture explode outside

the envelope of the normal combustion front.

An antiknock agent is a gasoline additive used to reduce engine knocking and

increase the fuel's octane rating by raising the temperature and pressure at

which ignition occurs.

'The typical antiknock agents in use are:

Tetraethyllead (Still in use as a high octane addative)

Methylcyclopentadienyl manganese tricarbonyl (MMT)

Ferrocene

Iron pentacarbonyl


11/22

Toluene

Isooctane

Cetane number or CN is a measurement of the combustion quality of diesel

fuel during compression ignition. It is a significant expression of the quality ofa diesel fuel

REFINING OF CRUDE OIL

An oil refinery or petroleum refinery is an industrial process plant where

crude oil is processed and refined into more useful products such as

petroleum naphtha, gasoline, diesel fuel, asphalt base, heating oil, kerosene,

and liquefied petroleum gas

Raw or unprocessed crude oil is not generally useful in industrial applications.Instead, the hundreds of different hydrocarbon molecules in crude oil are

separated in a refinery into components which can be used as fuels,

lubricants, and as feedstocks in petrochemical processes that manufacture

such products as plastics, detergents, solvents, elastomers and fibers such as

nylon and polyesters. . Different boiling points allow the

hydrocarbons to be separated by distillation. Since the lighter liquid products

are in great demand for use in internal combustion engines, a modern

refinery will convert heavy hydrocarbons and lighter gaseous elements into

these higher value products.

Oil can be used in a variety of ways because it contains hydrocarbons ofvarying molecular masses, forms and lengths such as paraffins, aromatics,

naphthenes (or cycloalkanes), alkenes, dienes, and alkynes. While the

molecules in crude oil include different atoms such as sulfur and nitrogen, the

hydrocarbons are the most common form of molecules, which are molecules

of varying lengths and complexity made of hydrogen and carbon atoms, and

a small number of oxygen atoms. The differences in the structure of these

molecules account for their varying physical and chemical properties, and it

is this variety that makes crude oil useful in a broad range of applications.

Once separated and purified of any contaminants and impurities, the fuel or

lubricant can be sold without further processing. Smaller molecules such asisobutane and propylene or butylenes can be recombined to meet specific

octane requirements by processes such as alkylation, or less commonly,

dimerization. Octane grade of gasoline can also be improved by catalytic

reforming, which involves removing hydrogen from hydrocarbons producing

compounds with higher octane ratings such as aromatics. Intermediate

products such as gasoils can even be reprocessed to break a heavy, long-


12/22

chained oil into a lighter short-chained one, by various forms of cracking such

as fluid catalytic cracking, thermal cracking, and hydrocracking. The final

step in gasoline production is the blending of fuels with different octane

ratings, vapor pressures, and other properties to meet product specifications.

Oil refineries are large scale plants, processing about a hundredthousand to several hundred thousand barrels of crude oil a day. Because of

the high capacity, many of the units operate continuously, as opposed to

processing in batches, at steady state or nearly steady state for months to

years. The high capacity also makes process optimization and advanced

process control very desirable.

Petroleum products are usually grouped into three categories: light distillates

(LPG, gasoline, naphtha), middle distillates (kerosene, diesel), heavy

distillates and residuum (heavy fuel oil, lubricating oils, wax, asphalt).This

classification is based on the way crude oil is distilled and separated into

fractions (called distillates and residuum) as in the above drawing.[2]

Liquified petroleum gas (LPG)

Gasoline (also known as petrol)

Naphtha

Kerosene and related jet aircraft fuels

Diesel fuel

Fuel oils

Lubricating oils

Paraffin wax

Asphalt and tar

Petroleum coke

Sulfur

Oil refineries also produce various intermediate products such as hydrogen,

light hydrocarbons, reformate and pyrolysis gasoline. These are not usually

transported but instead are blended or processed further on-site. Chemical

plants are thus often adjacent to oil refineries. For example, light

hydrocarbons


13/22

Specialty end products

These require blending various feedstocks, mixing appropriate additives,

providing short term storage, and preparation for bulk loading to trucks,

barges, product ships, and railcars:

Gaseous fuels such as propane, stored and shipped in liquid form under

pressure in specialized railcars to distributors.

Lubricants (produces light machine oils, motor oils, and greases, adding

viscosity stabilizers as required), usually shipped in bulk to an offsite

packaging plant.

Wax (paraffin), used in the packaging of frozen foods, among others. May be

shipped in bulk to a site to prepare as packaged blocks.

Sulfur (or sulfuric acid), byproducts of sulfur removal from petroleum which

may have up to a couple percent sulfur as organic sulfur-containing

compounds. Sulfur and sulfuric acid are useful industrial materials. Sulfuric

acid is usually prepared and shipped as the acid precursor oleum.

Bulk tar shipping for offsite unit packaging for use in tar-and-gravel roofing.

Asphalt unit. Prepares bulk asphalt for shipment.

Petroleum coke, used in specialty carbon products or as solid fuel.

Petrochemicals or petrochemical feedstocks, which are often sent topetrochemical plants for further processing in a variety of ways. The

petrochemicals may be olefins or their precursors, or various types of

aromatic petrochemicals.

Liquefied petroleum gas, also called LPG, GPL, LP Gas, liquid petroleum gas or

simply propane or butane, is a flammable mixture of hydrocarbon gases used

as a fuel in heating appliances and vehicles. It is increasingly used as an

aerosol propellant and a refrigerant, replacing chlorofluorocarbons in an effort

to reduce damage to the ozone layer. When specifically used as a vehicle fuel

it is often referred to as autogas.

Compressed natural gas (CNG) is a fossil fuel substitute for gasoline (petrol),

Diesel fuel, or propane/LPG. Although its combustion does produce

greenhouse gases, it is a more environmentally clean alternative to those

fuels, and it is much safer than other fuels in the event of a spill (natural gas

is lighter than air, and disperses quickly when released). CNG may also be

mixed with biogas, produced from landfills or wastewater, which doesn't


14/22

increase the concentration of carbon in the atmosphere.

CNG is made by compressing natural gas (which is mainly composed of

methane, CH4), to less than 1% of the volume it occupies at standard

atmospheric pressure. It is stored and distributed in hard containers at a

pressure of 200248 bar (2,9003,600 psi), usually in cylindrical or sphericalshapes.

USES OF OIL

1. Cooking oil

2.Emulsifier, a chemical which allows oil and water to mix

3.Wax, a class of compounds with oil-like properties that are solid at common

temperaturesA bottle of olive oil used in food

4.Cosmetics

5.Painting

Color pigments are easily suspended in oil, making it suitable as a supporting

medium for paints. The oldest known extant oil paintings date from 650 AD.

[10]

6.Heat transfer

Oils are used as coolants in oil cooling, for instance in electric transformers.

Oils are also used to enhance heating in other applications, such as cooking

(especially in frying).

7.Lubrication

Oils are commonly used as lubricants. Mineral oils are more commonly used

as machine lubricants than biological oils are. Whale oil is preferred for

lubricating clocks, because it does not evaporate, leaving dust, although its

use was banned in 1980.[11] As no suitable substitute is available, whale oil

is still used in space (in small quantities).[12]

8. Fuel

Some oils burn in liquid or aerosol form, generating light, and heat which can

be used directly or converted into other forms of energy such as electricity or

mechanical work. To obtain many fuel oils, crude oil is pumped from the

ground and is shipped via oil tanker to an oil refinery. There, it is converted

from crude oil to diesel fuel (petrodiesel), ethane (and other short-chain

alkanes), fuel oils (heaviest of commercial fuels, used in ships/furnaces),


15/22

gasoline (petrol), jet fuel, kerosene, benzene (historically), and liquefied

petroleum gas. A 42 gallon barrel (U.S.) of crude oil produces approximately

10 gallons of diesel, 4 gallons of jet fuel, 19 gallons of gasoline, 7 gallons of

other products, 3 gallons split between heavy fuel oil and liquified petroleum

gases,[13] and 2 gallons of heating oil. The total production of a barrel of

crude into various products results in an increase to 45 gallons.[13] Not alloils used as fuels are mineral oils, see biodiesel and vegetable oil fuel.

In the 18th and 19th centuries, whale oil was commonly used for lamps,

which was replaced with natural gas and then electricity.[14]

PLACES WHERE OIL REFINERIES ARE SITUATED IN INDIA----


16/22

List of Oil Companies in India

Aban Offshore ,


17/22

Bharat Petroleum ,

Bongaigaon Refinery and Petrochemicals Limited ,

Castrol India ,Chennai Petroleum Corporation Ltd ,

Essar Group ,

GAIL India Ltd

Gujarat Gas Company

Gujarat State Petroleum Corporation

Hindustan Petroleaum Corp. Ltd (HPCL)

IBPKolkata, India

Indian Oil Corporation Ltd (IOCL)

Indraprastha Gas New Delhi, India

Mahanagar Gas Mumbai, India

Mangalore Refinery and Petrochemicals Limited Mangalore,

Oil India Ltd Duliajan, Assam, India

ONGC Corporation

Petronet LNG Ltd.

Reliance Natural Resources Limited

Reliance Petroleum Ahmedabad, India

PIPE LINE LEAK DETECTION METHODS

Pipeline leak detection includes hydrostatic test after pipeline erection and

leak detection during service. This article mainly refers to in-service leak

detection.

Pipeline networks are the most economic and safest mode of transportation

for oil, gases and other fluid products. As a means of long-distance transport,


18/22

pipelines have to fulfill high demands of safety, reliability and efficiency. If

properly maintained, pipelines can last indefinitely without leaks.

Most significant leaks that do occur are caused by-------

A) damage from nearby excavation equipment, therefore it is critical to call

authorities prior to excavation to assure that there are no buried pipelines in

the vicinity.B) If a pipeline is not properly maintained, it can begin to corrode slowly,

particularly at construction joints,

C)low points where moisture collects, or

D)locations with imperfections in the pipe. However, these defects can be

identified by inspection tools and corrected before they progress to a leak.

Other reasons for leaks include accidents, terrorism, earth movement, or

sabotage.

The primary purpose of leak detection systems (LDS Systems) is to assist

pipeline controllers in detecting and localizing leaks. LDS Systems provide an

alarm and display other related data to the pipeline controllers in order to aid

in decision-making. Pipeline leak detection systems are also beneficial

because they can enhance productivity and system reliability thanks to

reduced downtime and reduced inspection time. LDS Systems are therefore

an important aspect of pipeline technology.

LDS Systems are divided into

1)internally based LDS Systems and

2)externally based LDS Systems.

Internally based systems utilize field instrumentation (for example flow,pressure or fluid temperature sensors) to monitor internal pipeline

parameters. Externally based systems also utilize field instrumentation (for

example infrared radiometers or thermal cameras, vapor sensors, acoustic

microphones or fiber-optic cables) to monitor external pipeline parameters.

3 Internally based LDS

3.1 Pressure/Flow monitoring

3.2 Acoustic Pressure Waves

3.3 Balancing methods

3.4 Statistical methods

3.5 RTTM methods

3.6 E-RTTM methods

3.7 Bubble Emission Method


19/22

4 Externally based LDS

4.1 Infrared radiometric pipeline testing

4.2 Acoustic emission detectors

4.3 Vapour-sensing tubes

4.4 Fibre-optic leak detection

INTERNAL SYSTEMS

1)Pressure/Flow monitoring

A leak changes the hydraulics of the pipeline, and therefore changes thepressure or flow readings after some time. Local monitoring of pressure or

flow at only one point can therefore provide simple leak detection. As it is

done locally it requires in principle no telemetry. It is only useful in steady-

state conditions, however, and its ability to deal with gas pipelines is limited.

[6]

2)Acoustic Pressure Waves

The acoustic pressure wave method analyses the rarefaction waves produced

when a leak occurs. When a pipeline wall breakdown occurs, fluid or gas

escape in a form of a high velocity jet. This produces pressure waves whichpropagate in both directions within the pipeline and can be detected and

analyzed. The operating principles of the method are based on the very

important characteristic of pressure waves to travel over long distances at

the speed of sound guided by the pipeline walls. The amplitude of a pressure

wave increases with the leak size. A complex mathematical algorithm

analyzes data from pressure sensors and is able in a matter of seconds to

point to the location of the leakage with accuracy less than 50 m (164 ft).

Experimental data has shown the method's ability to detect leaks less than

3mm (0.1 inch) in diameter and operate with the lowest false alarm rate in

the industry less than 1 false alarm per year.[7]

3)Balancing methods

These methods base on the principle of conservation of mass. In the steady

state, the mass flow entering a leak-free pipeline will balance the mass flow

leaving it; any drop in mass leaving the pipeline (mass imbalance ) indicates

a leak. Balancing methods measure and using flowmeters and finally

compute the imbalance which is an estimate of the unknown, true leak flow.


20/22

Comparing this imbalance (typically monitored over a number of periods)

against a leak alarm threshold generates an alarm if this monitored

imbalance.[6] Enhanced balancing methods additionally take into account the

change rate of the mass inventory of the pipeline. Names that are used for

enhanced line balancing techniques are volume balance, modified volume

balance, and compensated mass balance

4)Statistical methods

Statistical LDS Systems use statistical methods (e.g. from the field of decision

theory) to analyse pressure/flow at only one point or the imbalance in order

to detect a leak.[6] This leads to the opportunity to optimise the leak decision

if some statistical assumptions hold. A common approach is the use the

hypothesis test procedure

5)RTTM methods

RTTM means Real-Time Transient Model.[6] RTTM LDS Systems use

mathematical models of the flow within a pipeline using basic physical laws

such as conservation of mass, conservation of momentum, and conservation

of energy. RTTM methods can be seen as an enhancement of balancing

methods as they additionally use the conservation principle of momentum

and energy. An RTTM makes it possible to calculate mass flow, pressure,

density and temperature at every point along the pipeline in real-time with

the help of mathematical algorithms. RTTM LDS Systems can easily model

steady-state and transient flow in a pipeline. Using RTTM technology, leaks

can be detected during steady-state and transient conditions.

6)E-RTTM methods

Signal flow Extended Real-Time Transient Model (E-RTTM).

E-RTTM stands for Extended Real-Time Transient Model, fusing RTTM

technology with statistical methods. So, leak detection is possible during

steady-state and transient condition with high sensitivity, and false alarms

will be avoided using statistical methods.

For the residual method, an RTTM module calculates estimates , for MASS

FLOW at inlet and outlet, respectively. This can be done using measurements

for pressure and temperature at inlet (, ) and outlet (, ). These estimatedmass flows are compared with the measured mass flows , , yielding the

residuals and . These residuals are close to zero if there is no leak; otherwise

the residuals show a characteristic signature. In a next step, the residuals are

subject of a leak signature analysis. This module analyses their temporal

behaviour by extracting and comparing the leak signature with leak

signatures in a database (fingerprint). Leak alarm is declared if the

extracted leak signature matches the fingerprint.


21/22

7)Bubble Emission Method

This is a method to determinate gross leaks in flexible packaging. There is an

international standard covers this method - ASTM D3078.[9] Specimen is

submerged in an immersion fluid in a vacuum chamber. If consecutive

bubbles are observed in the vacuum chamber, it means there is a leak in thespecimen.

There are two necessary devices or materials needed in this method: Vacuum

Chamber: A vacuum chamber shall be a transparent container, capable of

withstanding approximately one atmosphere pressure differential, and fitted

with a vacuum-tight cover. A vacuum gage, an inlet tube from a source of

vacuum, and an outlet tube to the atmosphere shall be connected to the

chamber cover. Immersion Fluid: Use an immersion fluid which does not

degrade the package being tested. The test sample and test fluid shall be at

equilibrium with normal room temperature.

Externally based LDS

Externally based systems use local, dedicated sensors.[2] Such LDS Systems

are highly sensitive and accurate, but system cost and complexity of

installation are usually very high; applications are therefore limited to special

high-risk areas, e.g. near rivers or nature-protection areas.[5]

1)Infrared radiometric pipeline testing

Ariel thermogram of buried cross country oil pipeline revealing subsurfacecontamination caused by a leak.

Infrared thermographic pipeline testing has shown itself to be both accurate

and efficient in detecting and locating subsurface pipeline leaks, voids caused

by erosion, deteriorated pipeline insulation, and poor backfill. When a pipeline

leak has allowed a fluid, such as water, to form a plume near a pipeline, the

fluid has a thermal conductance different from the dry soil or backfill. This will

be reflected in different surface temperature patterns above the leak

location. A high-resolution infrared radiometer allows entire areas to be

scanned and the resulting data to be displayed as pictures with areas of

differing temperatures designated by differing grey tones on a black & whiteimage or by various colours on a colour image. This system measures surface

energy patterns only, but the patterns that are measured on the surface of

the ground above a buried pipeline can help show where pipeline leaks and

resulting erosion voids are forming; it detects problems as deep as 30 meters

below the ground surface.[10]

2.Acoustic emission detectors


22/22

Escaping liquids creates an acoustic signal as they passes through a hole in

the pipe. Acoustic sensors affixed to the outside of the pipeline create a

baseline acoustic fingerprint of the line from the internal noise of the

pipeline in its undamaged state. When a leak occurs, a resulting low

frequency acoustic signal is detected and analysed. Deviations from the

baseline fingerprint signal an alarm.[5][11]

3)Vapour-sensing tubes

The vapour-sensing tube leak detection method involves the installation of a

tube along the entire length of the pipeline. This tube - in cable form - is

highly permeable to the substances to be detected in the particular

application. If a leak occurs, the substances to be measured come into

contact with the tube in the form of vapour, gas or dissolved in water. In the

event of a leak, some of the leaking substance diffuses into the tube. After a

certain period of time, the inside of the tube produces an accurate image of

the substances surrounding the tube. In order to analyse the concentrationdistribution present in the sensor tube, a pump pushes the column of air in

the tube past a detection unit at a constant speed. The detector unit at the

end of the sensor tube is equipped with gas sensors. Every increase in gas

concentration results in a pronounced "leak peak".

4) Fibre-optic leak detection

The fibre-optic sensing leak detection method involves the installation of a

fibre-optic cable along the entire length of the pipeline. The substances to be

measured come into contact with the cable when a leak occurs, changing the

temperature of the cable. The distributed fibre-optical temperature-sensingtechnique offers the possibility to measure temperature along the pipeline.

Scanning the entire length of the fibre, the temperature profile along the fibre

is determined, leading to leak detection.

oil -all about it

Documents