Petrolium and gas processing

1. Petroleum and gas processing

2. WASEEM AKHTAR
NFC-IET-MULTAN

3. petroleum
• Crude oil that consist of different hydro
carbon compounds and many other organic
and inorganic compound, this word is
extracted from latin word petra =rock oleum
= oil . it is a naturally occurring, yellow-to-
black liquidfound in geological
formations beneath the Earth's surface, which
is commonly refined into various types of
fuels.

4. • It consists of hydrocarbons of various
molecular weights and other organic
compounds.[4] The namepetroleum covers
both naturally occurring unprocessed crude
oil and petroleum products that are made up
of refined crude oil. A fossil fuel, petroleum is
formed when large quantities of dead
organisms, usuallyzooplankton and algae, are
buried underneath sedimentary rock and
subjected to both intense heat and pressure.

5. A thick, flammable, yellow-to-black mixture of gaseous, liquid, and
solid hydrocarbons that occurs naturally beneath the earth's
surface, can be separated into fractions including natural gas,
gasoline, naphtha, kerosene, fuel and lubricating oils, paraffin wax,
and asphalt and is used as raw material for a wide variety of
derivative products. (American Heritage Dictionary)
The word petroleum comes from the Latin petra, meaning “rock,”
andoleum, meaning “oil.”
The oil industry classifies "crude" by the location of its origin and by
its relative weight or viscosity ("light", "intermediate" or "heavy").
The relative content of sulfur in natural oil deposits also results in
referring to oil as "sweet," which means it contains relatively little
sulfur, or as "sour," which means it contains substantial amounts of
sulfur.

6. history
• Red Indian used the oil in seepages as a
medicine, burning bushes.iraqi used crude to
joint jewellry by adhesive from crude
• Iraqi made first distilation unit of crude oil
from wine distiilary sold oil as commercial in
12th cenntury. In 18th century english made
first refinery. In first world war gasoline made
to run aeroplane engines. In 1930 markete of
petrolium was established

7. Origin of petroleum
• It is closely related to theory of vegitation . In old time
trees at the shore area burried and under high pressure
and temperature bacterial decomposition they convert
into petrol. The composition of petrol is c and H,s,o,Ni,
vandium.
• It is customery use a term preved reserve which means
well defined petroleum wells which are recoverable by
present production method
• Tar sands used to produce heavy crud due to sand
• Oil shale the oil in tar sands mixed with sand but shale
the oil is combined rock material known as kerogen

8. Oil shale
• Oil shale, also known as kerogen shale, is an
organic-rich fine-grained sedimentary
rock containing kerogen (a solid mixture
oforganic chemical compounds) from which
liquid hydrocarbons called shale oil (not to be
confused with tight oil—crude oil occurring
naturally in shales) can be produced. Shale oil
is a substitute for conventional crude oil;
however, extracting shale oil from oil shale is
more costly than the production

9. Tar sands
• Oil sands are either loose sands or partially
consolidated sandstone containing a naturally
occurring mixture of sand, clay, and
water,saturated with a dense and
extremely viscous form of petroleum technically
referred to as bitumen (or colloquially tar due to
its similar appearance, odour, and colour).
Natural bitumen deposits are reported in many
countries, but in particular are found in extremely
large quantities in Canada

10. Constituents of petroleum
• Crude petroleum contain thousand of
different chemical substances including solid
,liquid and gas , methane and asphalt. API
study has found 200 different compound
•
API = 141.5 - 131.5
SP.GRAVITY

11. Aliphatics or openchain
• These have formula CnH2n+2. The series of
large fractions are found in crude. These are
straight run .and distillate directly from crude
and known as n- parafins. These have poor
antiknocking properties. These have strong
pouring point (the liquid tempt at which liquid
become solid). These are saturated
hydrocarbond

12. Formula Name CAS-Number Structural Formula Chemical Classification
CH4 Methane 74-82-8 Alkane
C2H2 Ethyne 74-86-2 Alkyne
C2H4 Ethene 74-85-1 Alkene
C2H6 Ethane 74-84-0 Alkane
C3H4 Propyne 74-99-7 Alkyne
C3H6 Propene - Alkene
C3H8 Propane - Alkane
C4H6 1,2-Butadiene 590-19-2 Diene
C4H6 1-Butyne - Alkyne
C4H8 Butene - e.g. Alkene
C4H10 Butane - Alkane
C6H10 Cyclohexene 110-83-8 Cycloalkene
C5H12 n-pentane 109-66-0 Alkane
C7H14 Cycloheptane 291-64-5 Cycloalkane
C7H14 Methylcyclohexane 108-87-2 Cyclohexane
C8H8 Cubane 277-10-1 Cyclobutane
C9H20 Nonane 111-84-2 Alkane
C10H12 Dicyclopentadiene 77-73-6 Diene, Cycloalkene
C10H16 Phellandrene 99-83-2
Terpene, Diene
Cycloalkene
C10H16 α-Terpinene 99-86-5
Terpene, Cycloalkene,
Diene
C10H16 Limonene 5989-27-5
Terpene, Diene,
Cycloalkene
C11H24 Undecane 1120-21-4 Alkane
C30H50 Squalene 111-02-4 Terpene, Polyene
C2nH4n Polyethylene 9002-88-4 Alkane

13. Iso paraffin.
• these are branched chain material perform
better performance in internal combustion
engines than n- parafine. They areformed by
catalytic reforming, alkylation, polymerisation
or isomerisation. Only small amounts exsist in
crude

14. Olefin or alkene
• These are not found in crude oil but produce
in cracking. These are unstable molecules,
these are improve anti knocking quality of
gasoline. They are polymerized and oxidised.
Many petrochemicals are produced from
them e.g etylene, propylene,butylene

15. Aromatic compound
• This series has chemical formula CnH2n. They
are less instable and reactivity. These are
second abundant compound in crude e.g.
methylcyclopentane, cyclohexane. This group
are good fuels and higher molecular weight

16. Lesser component
• Sulfur has undesirable component of cude . It
has object able odor , equipment corrossion
and environmental hazard . So it is
requirement to eliminate the sulfur from
products of crude

17. Refinary process
• The crude from beneath of earth surface is
sent to refinery. In petroleum refinary
generation of usage able and scalable
fractions and products from crude oil by
distillation process or by chemical reaction
under the effect of heat and pressure.
• Synthatic crude oil produced from tar sand
known as bitumen heavier oil (shale oil ) used
as feed stocker in some refineries

18. • Crude petroleum is mixture of many organic
materials at different temperature. They can
be separated into different fractions by
distillation .crude oil obrained from the
resorvoir is darked to light brown color liquid .
It is known as conventional petroleum . This
material has difficult to flow has high API
gravity and difficult to flow .

19. Distillation
• Crude oil is converted into different fraction
by distillation process. The common methods
are
• Atmospheric disilation
• Vacuum distilation
• Aezotropic and extractive distilation
•

20. • Crude oil is known as feed stock . By distilation
different fractions are obtained
Crude feed stock
Light naphtha 1- 150 C
Gasoline 1- 180 C
Heavy naphtha 150 -205 C
Kerosene 205 – 260 C
 stove oil 205 - 270C
Light gas oil 260 – 315 C
Heavy gas oil 315 – 425 C
Lubricating oil 400 C
Vacuum gas oil 425 C
Residua 600 C
Rectifying
section
Stripping
section
furnace

21. • The temperature of distillation is below the 345C
because thermal decomposition of petroleum
conctituents take place at 350C. The temperature
above 425C is taking place in vacuum ditilation .
Asphalt is obtained from residue. It is obtained by
solvent extraction of residue.
• Sweet and sour mean in refinary is free from
sulpher and with sulfer content respectivly
• Crude contain mercuptants and H2S

22. Desalting and dewatering
• Crude oil from well contains gases water and
dirt . Thus pretreatment is done before sent to
refinary
• To remove dirt, water and gas by seperators
and gravity separator.
• Desalting is done by water washing and
sediment technique

23. NAPHTHAHYDROPHINEATMOSPHERIC
DISILATION
UNITLIGHT FEED
STOCK
GAS PLANT
GAS PLANT PETROCHEMICAL
H2SO4
ALKYLATION
KEROSENE
HYDROPHONE
JET FUEL
DIESEL OIL
CATALYTIC
HYDROCRACKER
CATALYTIC
REFORMING
MID
DITILATION
HYDROFIRE
KEROSENE
HEAVY OIL
G
A
S
O
LI
N
E
FUEL OIL
LPG
160C
160 -230
230 -300 C
340
RESIDUA

24. SOLVENT
DESPHALTING
ATMOSPHERIC
RESIDUA FOR
HEAVY FEED
STOCK
VACUUM STILL CLAY
TREATMENT
GASOLINE
CATALYTIC
CRACKING
SOLVENT
EXTRACTION
LUBE
WAXES
GREASE
AROMATIC
OIL
ASPHALT
COKE
R
VACU
UM
HYDR
O
TREAT
ER
340 -
470
470 -
560
PRECIPI
TATOR

25. REFINING
• Refining is done to convert the products
accourding to demands . When the products
fraction is produced from crude oil. There are
a number of products are into fractions are
present e.g gasoline, diesel oil, lubricants,
waxes

26. Distillation
• The separation of different fractions from the
crude due to their different boiling point
difference from the crude or feed stock is
called distillation.
• Types of distillation
1. Atmospheric distillation
2. Vacuum distillation
3. Aezotropic distillation

27. Atmospheric distillation
• The crude oil is introduced in distillation
column by flow pipe . The heating unit is
known as atmospheric pipe still . A heater or
furnace is provided to distillation column
• Distillation column is divided into two section
• Rectifying section and stripping section
• Rectifying is top side of column and bottom
side stripping section with refluxes

28. • The crude feed stock is entered in heater or
furnace where the feed is converted liquid to
vapor phase. Furnace remain under pressure
then a vapor of forth form stream is
produced. This stream is sent to distillation
unit . Where the vapors are moved in
rectifying section and liquid steam is moved at
the bottom side of column(stripping) .column
walls is internaly insulated with fire bricks

29. Vacuum distillation
• Vacuum distillation is done to separate less volatile
product such as lubricants from petrol because these
material are cracked when subjected to more heat in
atmospheric distillation . The boiling point of liquid is
done in atmospheric pressure is limited temperature
350C at which residue decompose or cracked
• Operating condition for vacuum distillation are 7-13
kPa. So that to minimize the pressure fluctuation in
vacuum tower
• Heavy gas oil is produced at the top of tower at 150C
• Lubricants is produced at 250 -350 C

30. Aezotropic or extractive distillation
• It is used to produce various liquid fraction . In
aezotropic distillation different chemical ability of
compounds to caused one or both component of
mixture boil at temperature other than on
expected . The addition of non indigenous
component form a aezotropic mixture that lower
the boiling point and facilitate separation of
liquid. The third component added should be
cheap ,stable and non toxic and readily
recoverable from components

31. • For successive distillation entrainer used in
one component separate into two liquids
phase on cooling it is direct recovered . If it is
not possible aezotropic entrainer is that
component which boiling point 10 – 40 C
below that of component

32. cracking
• Breaking of larger molecule of petroleum
products into small molecules in presence of
zeolite catalyst
• Types of cracking
• Thermal cracking
• Catalytic cracking
• Steam cracking

33. Thermal cracking
• C7H15.C15H30.C7H15 C7 H16
• +
• C6H12:CH22
•
+
• C14H28:CH
HEAVY GAS OIL
GASOLINE
GASOLINE
(ANTIKNOCK)
RECYCLE STOCK

34. Thermal cracking
• This process is best for heavier crude
• Heavier crude to lighter crude is produced
from this process
• In refineries heaver crude is produced during
off seasons of demand
• This method is best to handle residue of
distillate
• Braking of residue occur at high temperature
in absence of catalyst

35. • At elevated temperature in absence of catalyst
visbreaking ,delayed coking and fluid coking
occur
• Principle of cracking
• Higher boiling petroleum stock lower boiling products
• Free radical chain reaction
• free radical +hydrocarbon stable end product
• Heating treatment,mediocure heat treatment for low residential time
• Cracking naphtha aromatic(cracking) aliphatic
aromatic(condensation) aromatic higher aromatic(condensation)

36. • In kerosene gasoline is included which is too
volatile. In first world war gasoline is obtained
from Kerosene by thermal cracking unit . The
heavier component is converted into gasoline
• The bottom side of thermal cracking
production of lower boiling salable materials
,asphaltic material and unwanted coke remain
in residua

37. Thermal cracking is caused of
vis breaking
• Viscosity of oil is reduced during the cracking
operation . Thermal cracking is oldest cracking
process now near to obselete . Residua is
blended with lighter heating oil to produce
fuel oil . By reducing the vicosity then more
value able light heating oils are obtained that
is required for blending to meet fuel oil
specifications . The pour point is reduced of
waxy residua. Thermal cracking is done at 455
-510C and 345 – 2070 Kpa at heating

38. Cont. thermal cracking
• The primary products of this process is gasoline
,lighter gasolene, heavy gas oil. Heavy gas oil is
additonal feed for catalytic cracking unit.
• Crude oil passed through furnance where it is
heated to 480 C under pressure 690 Kpa . The
heating coil in furnance breaking the viscosity of
feed .the over head product of this section is low
quality gasoline and light oil at the bottom .

39. • This heated oil sent to flash chamber the
liquid product is cooled with gas oil and sent
to fractionater.
• The yield of hevy gas oil distilate and residual
tar of reduced viscosity . A quench oiil used to
terminate the reaction .this product is
unstable on sudden cooling and gives olefins
in form of gum

40. Furnace
Vacuum
residua
flasher
Fraction
tower
Vacuum
fraction ator
Low quality
gasoline
Heavy gas oil
Light
gasoline
gasoline
Heavy gas oil
480 C
690 kpa
Thermal cracking unit or destructive distillation
Or Coker
naphtha

41. Coking
• Coking is a series of thermal cracking process and
is used to convert the non volatile heavy fed stock
into lighter distillate product .the product of
coking is gas oil ,naphtha ,fuel oil ,gas oil ,and
coke
• Gas oil is primary product of this process while
coke is used as a fuel , electrode ,and production
of metallurgical coke
• DELAYED COKING PROCESS
• FLUID COKING PROCESS
• FLEXI COKING PROCESS

42. • It is semi continuous process in which heat is
transferred to large soaking or coking drum in
which residance time is important factor to
complete cracking reaction
• The feed of vacuum residue and thermal process
residue is used . The feed stock is introduced the
product fractionator . At the bottomside recycle
of heavy product are heated in furnance which
outlet temperature is 480 -515 C.

43. • The heated feed stock then enter one of pair of coking
drum ,where cracking drum where cracking reaction
continue . The cracked products leave as overhead
materials and coke deposits form inner surface of drum
and cooled by water . The coke drum temperature is
415-450 C with pressure 103 -621 kpa overhead
product go to the fractionators. Where naphtha are
heated oil is recovered . The non volatile material is
combined with preheated fresh feed and returned to
furnace before coming porous coke . Coke remain in
coke drum for 24 hrs and removed hydraulically

44. FRACTIONATOR
HEATER
NON
PARATIVE
COKING
DRUM
SOAKER
OPENING
COKING
DRUM
SOAKER
GAS
NAPHTHA
GASOLINE GAS OIL
HEAVY OIL
DELAYED COKING
ROCESS
COKE

45. Fluid coking
• In fluid coking there are two vessels a reactor
and burner . Coke particles are circulate
between reactor and burner . The reactor
fluidized coke particales and sream is
introduced at the bottom of reactor to
fluidized bed

46. Fluidized coking
•
steam
Fluidized
bed
reactor
burner
Flue
gas
coke
air
Heavy
stock
Over
head
product
Excess
coke
Makeup
coke

47. Flexi coking
• It is continuous process . It is similar to fluid
coking process but difference is that in
gasification section excess coke can be gasified
to produce refinery fuel gas. Flexi coking
process in which excess coke is made is
reduced in view of gradual incursion of
heavier feed stock into refinery operation .
Such feed stock are not good for production of
higher yield of coke in thermal or catalytic
process

48. Scrubber
Heater
Gasifier
Reactor
product to
fractionators
recycle
bituminous
steam
Purge
coke
Fines
remover
Coke gas to
sulfur
Coke
fines
cooler
Steam
generator
air
steam

49. Catalytic cracking
• Catalytic cracking is similar to thermal cracking
with a difference presence of catalyst
• catalyst
• In firstly catalytic cracking process acid catalyst
were used but now a days low alumina catalyst
that is amorphous solid contain 87% silica and
13% alumina while alumina catalyst contain 25%
alumina and 75%silica in spherical form pellets
that are used in fixed bed and moving bed fluid
bed reactors

50. • Catalytic process is used today moving bed unit
and fluidized bed unit
• Theramafor catalytic cracking (TCC) and fluidized
bed catalytic cracker(FCC) is fluidized bed , the fcc
units is classified as bed or riser depends upon
the major fractions of cracking reaction occurs .
• The hot oil feed is contacted with catalyst in bed
or riser of reactor as cracking reaction progress
deactivation of catalyst starts by formation coke
on the surface of catalyst . The catalyst and
hydrocarbon vapors are separated mechanically

51. • Oil remaining on the catalyst is removed by steam
stripping before catalyst enter the regenerator .
The oil vapors are taken overhead to a
fractionators tower the oil vapors are taken
overhead to a fractionation tower for separation
into stream having the desired boiling range.
• regenerative the spent catalyst flows into
regenerative and reactive by burning off coke
deposits with air . Regenerative temperature is
carefully controlled prevent catalyst deactivation
by over heating carbon is burn off and flow the
controlled ai carefully catalyst are seperated by
cyclone seperator and electrostatic precipitator is
used. How ever some units used steam stripping

52. Fixed bed process
• Several reactors in series with loading catalyst
in which feed stock is input . Feedstock flows
through catalyst bed discontinuous the feed
stock and removed the coke from catalyst by
burning the catalyst and reused in reactor . In
fluidized catalytic cracking the size of
particales of catalyst peelets are 70 microns
which behave as a fluid with vapor.

53. • The fluidized catalyst circulated continuously
between the reaction zone and regeneration
zone and transfer the heat regenerator to
reactor ( separator)
• Dense phase of fluidised catalytic bed in the
reactor vessel there is most of cracking occure
in the reactor bed . The extent of reaction is
controlled by depth of bed and temperature
so high rate of cracking occur in riser attempt
was made to regulate the reaction by
controlling riser conditions

54. • The zeolite catalyst for cracking is used by
refinaries
• Reactor works as separator as well as cracking
performing
• It separate the catalyst and hydrocarbon vapor
• Feed is injected in fluidized cracker by spray
nozzles , the fresh feed and recycle feed is
preheated by waste heat boiler ,enter in the
base of feed riser where they are mixed with
hot generated catalyst . The heat of heated
catalyst is enough to rise the temperatur of
cracking .

55. • This mixture of catalyst and hydrocarbons
vapors are sent to separator, cracking is
started when vapors contacted with high
temperature catalyst . Hydro carbons vapors
are sent to factionator while catalyst is
regerated in regerator and sent back to riser
• The leaving catalyst from reactor is known as
spent catalyst , by steam stripping remove
from the catalyst absorbed hydrocarbon .
• Regenerator temperature is controlled by
620 -845C

56. In the regenerator burn the coke on catalyst or
either by carbon monoxide to carbon dioxide
technique was used in older regenerator . The
flue gases from the regenerator sent to waste
heat boiler.
In new technology deposited carbon is stem
reformed and produce hydrogen and carbon
monoxide and carbon dioxide and convert the
carbon monoxide in to CO2 and passed through
w.h.b

57. regen
erator
reactor
air
fractio
nator
Recovery
gas
gasoline
Light gas
oil
Heavy
gas oil
Slurry
oil
Slurry decantation
Fresh feed
Regen
erator
catalyst
Slurry
settler
Spent
catalyst
w
.h
.b
To final
dust
collection
F.C.C UNIT
Steam

58. Hydro cracking
• Hydro cracking is done >350C in which pressure
held 1000 – 3000 psi and conversion of feed stock
to lower boiling products
• During the hydro cracking lower yield gaseous
compounds are obtained such as methane ,
ethane, propane less desirable than gasoline
• In first preheating stage hydro cracking process
the main feed stock to hydrocarbons and
ammonia and hydrogen sulfide by hydrogenation

59. • Hydro cracking is done by lowering
concentration of N2 and S is 50ppm at 340 –
390C and 1500 -2500 psi for 1- 1.5 contact
time
• In this stage used catalyst may be nickel
,tungsten , molybdenum, sulfide

60. • Thiols R-SH +H2 RH+H2S
• Disulfide R-S-S-R +H2 RH+RH+H2S
• THIOPEN
S
H2 nC4H10 H2S

61. Most of hydro cracking is completed in
secondary stage. Hydrogen sulfide ,ammonia
and low boiling product is removed . NH3 and
H2S are removed in first stage catalyst and the
remaining oil which is low in nitrogen and
sulfer content is passed through second stage
catalyst is done 300 – 370C and 100 – 2500psi
and 0.5 -1 hr contact time .
Conversion of gasoline is done with catalyst high
boiling product is combined with fresh feed
and recycled over catalyst until it is completed

62. • The catalyst for second stage is also bifunctional
catalyst containing hydrogenating and acid
component . Metal such as nickel , molybdenum ,
tungsten and palladium is used . Catalyst are
regenerated after 2.5 – 3 years
• hydro treating
• The catalytic process converts sulfur and N2
containing hydrogenation catalyst are Ni ,
palladium ,platinum ,cobalt and iron . By
temperature increasing hydrogenation is reversed
. Hydrogenation is reversed . Hydro treating is
done in reactor at 300-345C at 500-1000psi. The
reaction take place in vapor phase.

63. • After passing through oil is cooled and separate
from excess hydrogen recycled through reactor
and sent to stripper tower where H2S is formed
by hydrogenation reaction . Steam is produced
by vapor stream and sent back to stripper
tower. Catalyst is regenerated in several
regenerations

64. Catalytic hydrocracking
• Hydrogenation is done in catalytic hydro
cracking in petroleum refinery
• Hydro cracking is done due to several
following reasons
1. Demands for petroleum products has shifted
to high demand for gasoline, diesel, and jet
fuel as compared to other fuels product
usage

65. 2. By product hydrogen at low cost and large amounts
has become available from catalytic reforming
operations
3. Environmental issues due to sulfur limits and
aromatics compound in motor fuels has increased
In hydro cracking process convert the lignite into
gasoline
By improving the new catalyst modern hydro cracker
distillate come into ages operation could be done at
low pressure than earlier units . In this way demand
for higher octane unleaded gasoline
Jet fuels and lower sulfur content diesel fuel is
permoted

66. • Advantage of catalytic cracking
1. Better balance of gasoline and distillate
production
2. Greater gasoline boiling range naphtha yields
3. Improved gasoline pool octane quality and
senstivity
4. Production of relatively high amounts of
isobutene in butane fraction
5. Supplementing of fluid catalytic cracking to
upgrade heavy cracking stocks, aromatics ,cycle
oils and Coker oil to gasoline jet fuels ,and diesel

67. • In catalytic cracking cracked the parrafins by
using gas oil as charge stocks . Where as hydro
cracker uses more aromatics oils and Coker
distillates as a feed. zeolite cracking catalysts
improve the yield of gasoline in this process .
• Residue is difficult to cracked by this catalyst
to overcome this difficulty residue is blended
with fuel and burns in cracker in this way
residue crack into aromatic components

68. Hydro cracking process
1. GOFFING PROCESS
It is fixed bed regenerative process , a molecular
sieve of catalyst is installed here . The process
may be done in single stage or two stage
depends upon the size of unit and production
the operating condition for the process are in
the range of 660 – 785 F and 1000 – 2000
psig . For the most sauitable condition single
stage is preffered

69. • The fresh feed is mixed with makeup hydrogen
and recycle gas are passed through heater to
first reactor . If the feed is not hydrotreated
,there is a guard reacror is provided which is
impregnated with catalyst cobalt and
molybedinum on silica –aluminia convert the
organic sulfur and nitrogen compound into
H2S ,ammonia and hydrocarbon to protect
catalyst of following reactor

70. • The hydro cracking reactor is operated at
sufficiently high temperature to convert the 40 -
50%by volume of reactor effluent to material
boiling below 400 F . The reactor effluent goes
through heat exchanger to high pressure
separator where hydrogen rich gas is separated
and recycle to the first stage for mixing both
make up hydrogen and fresh feed
• The liquid product from the separator is sent to a
distillation unit .where gasoline and lighter gases
and naphtha as overhead product

71. • Jet fuel and diesel oil stream is recovered as
liquid fuel.
• The bottom of fractionators unit is taken as
feed of second stage reactor system .
• The unit can be operated to produce gasoline
and lighter products or to maximize the jet
fuel or diesel fuel.

72. • The bottom of stream from fractionators is
mixed with recycle hydrogen from second
stage and sent through a furnace to second
stage reactor. Here the temperature is
maintain to bring the total conversion of the
unconverted oil from the first stage and
second stage recycle to 50 -70% by volume
per pass . The second stage product is
combined with the first stage product prior to
fractionation

73. • Both the first and second stage reactors contains
several beds of catalysts . The major reason for
having separate beds is provided for injection
cold recycled hydrogen between the beds help to
maintain a more uniform utilization of catalyst
• When operating hydrocarbons for total
conversion of distillate feeds to gasoline the
butane and heavier liquid yields are generally
from 120 to 125 vol% of fresh feed.

74. feed
H2 recycle H2 make up
gas
C1-C4
naphtha
diesel
H2 make up
H2 recycle

75. REFORMING
• When high octane number gasoline is needed
to produce and improving the gasoline octane
number by fractions . Straight run gasoline has
low octane number and by this process
improve the high octane number and by this
process improve the high octane number. All
these are done in thermal reforming.

76. Reforming types
1. Thermal reforming
2. Catalytic reforming
3. Steam reforming

77. thermal reforming
• The process similar to thermal cracking in which
cracking converts heavier oil into gasoline while
in reforming converts gasoline lower octane is
converted into higher octane at high temperature
• Thermal reforming is less effective and less
economical than catalytic reforming converts low
octane grade gasoline into high grade octane
gasoline
• Thermal reforming reforms octane number 65-80
while catalytic reforming reforms 95-105

78. Catalytic reforming
• Catalytic reforming is conducted in presence of
hydrogen over hydrogenation ,dehydrogenation
,catalyst used in this process are same in catalytic
cracking and similarly contain naphtha
,hydrocracker naphtha contain naphthenic
compound
• Dehydrogenation is done in catalytic reforming
and hydrogen gas is produced in large quantities,
hydrogen is recycled through reactors where
reforming is done by chemical reaction . In
catalytic reforming by product is H2

79. • Catalytic reforming is carried out by feed of
naphtha treating with H2(removing of Sand N)
• The mixture of H2 and naphtha to a furnance it is
heated at temperature of 450 -520 C and then
passed through fixed bed catalytic reactor and
hydrogen pressure is 350 – 2700Kpa. The catalyst
used are platinum rehnium and alumina based .
Platinum promotes the dehydrogenation
,hydrogenation reaction . Non platinum catalyst
are used in regenerative process for feed stock
containig S in series of reactors

80. Isomerisation or polymerisation
• Isomerisation is used to additional feed stock
for alkylation unit for isobutene product or
higher octane fractions for gasoline blending
for( pentane and hexane) . The latter
application is useful in the production of
reformulated gasoline by increasing octane
number while converting or removing
benzene. Iso butane is also used for synthesis
of methyl tetra butyl ether (MTBE)as additive

81. • That maintaining octane rating in gasoline instead
of tetra ethyl lead
• Initially aluminum chloride was the catalyst used
to isomerizes butane, pentane, and hexane. Since
then supported metal catalysts have been
developed for use in high temperature process
that operate at 370-480C and 300-750psi . Where
as aluminum chloride catalyst is used in fixed bed
reactor . Normally platinum is used as a catalyst
in fixed bed reactor

82. The reaction is occurred between 40-480C and 150-
100Psi depends upon particular feed stock and
processes
ALKYLATION the
combination of olefins+paraffins to form iso
paraffins in the term of alkylation. Alkylation is
desirable blend stock because it has a relatively
high octane number and dilute the total aromatic
contents. Reduction of olefins in gasoline blend
stock by alkylation also reduces tail pipe emission

83. • In refinery practice butylene are alkylated by
reaction with isobutane -octane . Alkylate is
composed of a mixture of isoparafins which
octane number vary with the olefins which
they were made . Butylene produces the
highest octane number. Propylene the lowest
and amylene the intermediate value

84. • Propylene , butylene or amylene are
combined with isobutene in the presence of
an acid catalyst such as sulfuric acid or
hydrofluoric acid at low temperature 1-40C
and pressure 102- 1035Kpa. Both of these
catalyst are used in refinaries . The acid is used
to form emulsion with reactants . Butene
consumes less acid than propylene

85. Polymerization
• In this process olefin gases are converted into
higher molecular weight liquid product and
suitable gasoline polymerization product are
obtained . Propylene and butylene from
cracking process selective olifins dimers trimer
and tetrament production .
• This oligomerisation done with these products
C4 –C12 are liquid polymerized saturated
material that cannot effective

86. 1. Thermal polymerization
2. Catalytic polymerization
1. Thermal polymerization
Thermal polymerization is not effective as catalytic
polymerization but has advantage that cannot
be included to react catalyst . The process
consist of vapor phase cracking e.g. propane and
butane followed by prolong period at high
temperature 510-595C for reaction to proceed
near combustion

87. • Olifins are polymerized by means of acid catalyst .
Olifins rich feed in presence of H2SO4 copper
pyrophosphate and phosphoric acid at 150 -220C and
150 – 1200Psi depends upon feed stock requirement .
Phosphate is used in polymerization unit.
• TREATING
• Since the original crude oil contain some sulfur
compound and gasoline has sulfur compound including
H2S,mercuptants, sulfides, disulfides and thiophene
removing of S is called sweating product

88. Hydro treatment
Alkali
treatment
Acid
treatment

89. ALKALI TREATMENT
• Hydro treatment is important technique for all
types of petroleum product and sauitable to
evaluate H2S and mercuptant compound .
• RSH is removed by soda treating
• H2S+2NaOH Na2S+2H2O
• RSH+NaOH NaSR+H2O
• 4NaSR+O2+2H2O RSSR+4NaOH

90. • This method is effective for low concentration
steam generation method is used to remove
mercuptants such as gasoline, low boiling
solvents . The caustic is regenerated by steam
blowing in stripper tower . The nature and
concentration of mercuptants to be removed
by quantity of process

91. ACID TRATMENT
• This treatment of petroleum product is done
in petroleum industry . Acids such as
hydrofluoric acid, hydrochloric acid and nitric
acid and H2SO4 are used in refine Kerosene
and lubricants . Acid treatment is done for
cracked gasoline and paraffinic kerosene

92. CLAY TREATMENT
• A tower contain clay pellets . Clay absorb the
impurity from petroleum fraction. Clay after
removing recovered by burnt the absorbed
matters . It is effective for lubricants , gum
forming in gasoline. Clay removing the asphalt
material .

93. SOLVENT TREATMENT
• SOLVENT TREATMENT
SOLVENT
EXTRACTION
SOLVENT
DEWAXING

94. SOLVENT TREATMENT
• The solvent is used in extraction process
include propane and creslyic acid
,2,2dichlorodiethyl ether , phenol , furfural , SO2,
benzene and nitrobenzene . Solvent processing is
done for lubricants at the end of crude . Solvent
extraction process is done to separate the
impurity for purification of gasoline, kerosene ,
diesel oil , e. g propane desphalting is removed by
extraction process that comes from vacuum
distillation process ,removing asphalt from crude
oil

95. dewaxing
• In dewaxing process solvent is benzene,methyl
ethyl ketone, methyl isobutyl, ketone ,
propane ,petroleum naphtha , ethylene
dichloride , methylene chloride , sulfur di
oxide and n- methylpyrollidineone.
PROPANE DESPHALT SHOWN BELOW

97. HEAVY
FEED
STOCK
PROPANE
LIQUID
EVAPORATOR STRIPPER
FLASHER
STRIPPER
PROPANE
RECOVERY

98. GAS PROCESSING
• The gas stream is produced during petroleum
refining usually contain many noxious
constituents that have adversed effect on the use
of gas for other purposes e.g fuel or
petrochemical feed stock and some degree of
cleaning is required
• Gas processing is fall into three category
1. Removal of gaseous impurity
2. Removal of particular impurity
3. Ultrafine cleaning

99. • The operation or the need to produce a pure gas
stream . Because there are many variables in gas
streaming treatment
• Several factors must be considered
1. Types and concentration of contaminations in
the gas
2. The degree of contamination removal is desired
3. Selectivity of acid gas removal reqired
4. The temperature , pressure , volume , and
composition of gas to be processed

100. 5. CO2 and H2S ratio in gas
6. The desirability of sulfur recovery on account
of process economics
Process selectivity indicates that the
performance with which the process remove
one acid gas component relative
performance to another
e.g some process desighn are fixed to remove
H2S

101. • Thus it is important to consider the process
selectivity for H2S compare to CO2 removal .

102. LIQUID PETROLEUM GAS (LPG)
• Specific hydrocarbons such as propane
,butane , pentane ,this mixture exist in
gaseous state under atmospheric state under
atmospheric ambient condition but can
converted to liquid state under moderate
pressure and ambient temperature . This
product is known as LPG.

103. • The presence of ethane in LPG must be
avoided because of instability of this lighter
hydrocarbon to liquefy under pressure and
ambient temperature and its tendency to
show abnormal high pressure in LPG contaner
• The pressure of pentane is avoided in LPG
because this hydrocarbon is liquefied state
and ambient temperature and pressure can be
seperated as liquid state gasoline

104. • LPG gases precipitated asphaltic and resinous
material from crude residue while lubricating
oil constitution remains in solution . All
liquefied gases is possess this property to
some extent propane and butane are used to
desphalt residual lubricants because their low
relative cost

105. GASOLINE
• The naphtha fraction from crude oil
distillation is ultimately used to make gasoline
. The two streams are isolated early in refining
scheme so that each can be refined separately
for optimum blending in order to achieve
reformed specification
• Gasoline is complex mixture of hydrocarbon
that boils below 200C .

106. • The H/C constituents in this boiling range are
those that have C4-C12 composition
• Gasoline can very widely in composition even
those have same octane number
• Because of difference in composition of
various gasoline . Gasoline blending is
necessary . The physical process of blending
the composition is simple but determination
of each component is difficult

107. • Aviation gasoline usually used in an air crafts
with boiling range 38 -170C than automobile
gasoline 0- 200C . Some amount of butane is
added to vaporize the gasoline in winter
• In air crafts vapor pressure must be changed
as temperature of fuel change occur but not
boiling in fuel tank . Gasoline combustion is
smooth and fit for precise combustion cycle,
ignite with minimum spark

108. • The extra pressure pulses resulting from
spontaneous combustion are audible above
normal sound of engine are abnormal
combustion
• To stabelize octane number minimum
knocking , isooctane are normal heptane in
proper rate are used as anti knocking

109. SOLVENTS
• Naphtha is refined and unrefined product
mixture of refinary and is obtained from
fractional distillation . Mainly used in paint
industry , dry cleaning , and rubber industry
• Turpentine is used in paint industry which is
abundantly found in naphtha

110. KEROSENE
• Kerosene is straight run product petroleum
fraction that boils 205 -260C. C12 – C15 is
kerosene containing product ,low portion of
aromatic and unsaturated H/C with low S –
content in kerosine
• The other important fuels are Diesel fuel , Jet
fuel, coming from Kerosene fraction

111. • Fuel oil is classified as distillate fuel oil and
Residual fuel oil
1. Distillate Fuel Oil Distillate fuel oil is vaporized
and condense during distillation process . It has
definite boiling range and not contain asphaltic
material
2. Residual fuel oil
Fuel oil is contain residue from crude distillate
.Domestic stove oil and diesel heavy fuel is
obtained from this fraction

112. • Ship , marine , are obtained from residual fuel

113. LUBRICATING OIL
• Lubricating oil distinguish from other fractions of
crude oil and obtained from boiling range >400 C
. They are high viscous
• Lubricating oil is classified as in motor lubricants ,
aviation lubricants, and turbine oil
• Lubricating oil is used in intermittent service and
show least possible variation viscosity with
respect to temperature and must be changed at
frequently interval to remove foreign matter
collected during service .

114. • The stability of such oil is therefore of less
importance than stability of oil used in
continuous service for prolonged period
without removal . The importance of
lubricating oil work in the engine maintain its
constant temperature and avoid its abnormal
shut down

115. wax
• Waxes are classified in two classes paraffin wax in
distillate and micro crystalline waxes residue
• The melting point not related to boiling point
because waxes contain hydrocarbons of different
chemical structure .
• Waxes grades are related to different melting
point and oil content paraffin waxes is a solid
crystalline mixture of straight chain normal
hydrocar bon range C20- C30and higher

116. • These are solid at 25C while petroleum jelly
contain solid and liquid H/C wax producing by
wax sweating
• Recrystallization process is first wax producing
method in which slackes or raw wax is
warmed to a temperature where wax became
liquid and pure wax is collecting by dropwise
at bottom . Leave behind higher melting point
residue

117. Dewaxing processes
• Commonly there are two different methods
are for producing wax
1. Solvent dilution
2. Chilling to crystallize the wax and filter
Wax crystals are formed by chilling through walls
of scraped surface chiller oil . Wax solvent
seperated by rotary vacuum filter . Solvent
used for dewaxing are naphtha ,propane ---

118. • ---, SO2 , acetone –benzene , tricolor ethylene
,ethylene dichloride –benzene (barisol),
methyl ethyl –ketone –benzene(benzol),
methyel –n butyl ketone , methyel n-propyl-
ketone and other solvents are N-methyel –
pyrrolidinone, dichloroethane – methyelene
di chloride and propylene –acetone.

119. • Solvent dewaxing can be applied to lighter
intermediate and heavy lubricating oil
distillates but each distillates produce
different kind of wax and each is actually a
mixture of number of waxes the wax obtained
from light parrafin distillates consist of a series
of parrafin waxes .The m.p is 30-70 and hard
crystals form on cooling.The wax contain 60-
90 c hard and small crystals called
microwaxes.

120. Propane process
• Propane is dilute form is evaporated by
reducing pressure so as chill the sluary to
desired filtration temperature and rotary
pressures filtration is applied formation of
solid waxes ,n parrafine is refrigerated and
separated by filtration this method is used low
viscosity lubricants which remain in liquid
state at low temperature . The oil of transform
are hydrolic oils.

121. • Silicon carbonate manufacturing from which
accetylene is produced.
• Coke produced from low quality crude oil is
mixed with coal and burns as fuel .
• Coke is used in fluidized bed combustors or
gasifiers for power generation.

122. Centrfuging seperation
• Centrfuging separation of petroleum form
residue by centrifuging dewaxing . Crude oil in
dissolved in naptha and chilled -18C or lower
which causes separate wax then it is sent to
battery of centrifuge when wax is separated
from liquid . Similarly the modren method is
used to collect HCL of normal parrafines.

123. Catalytic dewaxing
• Catalytic dewaxing is hydro cracking process
operated at temperature 280-400C and 300-1500
psi . The condition for specific dewaxing
operation depends upon nature of feed back
stock and product are pour point required . The
catalyst is used to crack the normal paraffin's.
Another catalytic dewaxing process is involved
selective cracking for normal parrafine and those
paraffin that minor branching in chain catalyst is
regenerated by mono oxidation treatment.

124. • A catalytic dewaxing process can be used to
dewax a variety of lubricants base stock it has
potential to replace solvent dewaxing.

125. Asphalts
• This is residual of distillation that can be
produced by propane desphalting . Asphalt can
be made softener by blending hard asphalt with
extract obtained from solvent treatment of
lubricating oil .
• Soft asphalts can be converted into hard asphalt
by air oxidation . Cutback asphalt are mixture in
which hard asphalt has been diluted with light oil
to permit application as a liquid without heating .

126. • They classified as rapid medium and slow
curing depends on volatility of diluents which
govern the rate of evaporation .
• Asphalt can be emulsified with water to
permit application without heating . Such
emulsion are normal oil in water . They are
used road making soil stability , water
proofing.

127. Coke
• This residue is obtained by destructive
distillation (coking residue)
• Petroleum coke is employed for number of
purposes the principle use is carbon electrode
manufacturing ,for AL refining, which
requiring high purity carbon that low in ash
and free sulphur.
• Coke is employed in manufacturing of carbon
brushes.

128. FURNACE
REACTOR
LOW
TEMPERA-
TURE FLASH
HIGH
TEMPER-
ATUTE
FLASH
NAPHTA
DISTILATI
ON