Internship Report
By: Hafiz Muhammad Junaid Department of Petroleum Technology, University of Karachi. Dated: 08-07-2008
[email protected]
Acknowledgment It was great honour for me to join PRL as internee. It was a great experience. It was the first time to see the industrial equipment and the process of distillation which before that I was only read in the books. In this regard I really thankful to the officials of PRL Mr. Sakhawat, Mr. Azhar, Mr. Muhammad Khalil, Mr. Kamran, Mr. Ejaz, Mr. Bilal, Mr. Inam ur Rehman and all others whose name I am missing on this paper.
_________________________
Hafiz Muhammad Junaid
Internship Report
Table of Contents Unit
Page #
Company Profile
4
Process Summary
5
Desalter unit
6
Crude Unit
7
Naphtha Reforming Unit
8
Steam Generation Unit
9
Electricity Generation Unit
9
Wastewater Treatment Plant
10
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report Company Profile Pakistan Refinery Limited (PRL) was built and commissioned in October 1962 at Karachi in alliance with major foreign oil companies like Burmah Oil California, Texas Oil Corporation, Shell Petroleum Corporation and Esso Standard Eastern Inc. PRL is a hydro-skimming refinery with a capacity of 50,000 barrels per operating day. The process configuration constitutes desalting, crude distillation, hydrodesulphurization, platforming and LPG units. Though, designed to process Iranian Light, it has acquired the ability to process a variety of imported and indigenous crude oils to produce energy products namely-LPG, MS Unleaded 90 RON, Naphtha, Kerosene, HSD, JP-1, JP-8, MTT and Furnace
Oil.
PRL,
since
inception
has
been
the
principal
manufacturer and supplier of petroleum products to the domestic market and Pakistan defence forces. It continues to serve the energy needs of the country with professional excellence and high degree of commitment. PRL takes pride in the edge it enjoys over its competitors in respect of efficiency, lower operating cost, high quality human resources, reliability and introduction of newer generation technologies. PRL has demonstrated its excellence as a first rate corporate citizen by serving community and demonstrating total commitment to the cause of Health, Safety and Environment. PRL is proud to be the leader in integrated HSEQ Management System, being the first in Pakistan’s oil industry to achieve OHSAS 18001:1999 and ISO 14001:2004 certification. No. of sites = 2 (Refinery and Oil Storage Terminal at Keamari) No. of Employees = 275 Annual Turnover = Rs. 57.4 billion (July 06- June 07)
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report
Process Summary Ø Desalter Unit Ø Crude Unit Ø Catalytic Hydrodesulphuriser Unit Ø Platformer Unit Ø Effluent Water Treatment Plant Ø LPG Recovery Unit Ø Reverse Osmosis Unit Ø Water Softening Unit Ø Steam Generation Unit Ø Electricity Generation Unit
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report Desalter unit
Desalting Unit Desalting unit is the very important unit in the refinery. As crude oil is taken from the underground reservoir therefore it is contain salts which should be removed from the crude to avoid corrosion, scaling, fouling and poisoning of catalyst. So, crude should be desalted. Desalination is carried out by mixing the crude oil with water and emulsifying agent to make a emulsion because the salts are trapped in the crude oil and in emulsion form. Then demulsifying agent (Petrolite) is added to remove the salts and electrostatic force is applied to coalesce the particles.
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Internship Report Crude Unit Distillation Tower 101-E:It is the main distillation tower, it comprises of 20 trays out of which top 12 trays are sieve and remaining 8 trays are bubble cap trays.
The flash zone is at the 17th tray. A crude from the desalter is heated in the furnace @ 350OC and enters in the 101-E. 101-E gives three streams: 1.
Overheads
2.
Gas oil
3.
Residue
Overheads are sent to the column 102-E where it splits into three streams i.e. 1. Gasoline and LPG (top) 2. Naphtha (from Middle) 3. Kerosene (Bottom)
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Internship Report
Top stream is send to the column 105-E where LPG is separated from the gasoline and after washing with water and CTC it is rundown whereas gasoline is passes through a heat exchanger and sent to through the gasoline stabilizer where small H/Cs i.e. C4 and C 5 remove from it and gasoline is run down.
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Internship Report NAPHTHA REFORMING UNIT Mid stream is send
to
the
hydrodesulfurizer remove sulphur
the
unit to
impurities
of
nitrogen
in
and
combine form. It is necessary to remove these impurities as they are poisonous for catalyst.
Hydrodesulfurizer Unit The Naphtha
produced is not suitable to used as motor fuel i.e. it is reform
in
the
Platforming
unit. It consist of three reactors with Pt/Rd catalyst and three furnaces. Feed
enters
temperature
of
at
the
490OC
to
Platforming unit
507OC. In first reactor Naphtha is dehydrated, in second reactor isomerization of paraffins takes place and in third reactor hydrocracking is occurred. The produced naphtha is of 86 RON.
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Internship Report STEAM GENERATION UNIT In PRL steam is used for various purposes. It
is
column
used for
in
distillation
stripping,
in
turbine driven pumps and compressors etc.
This steam is generated by three boilers which are D – shape water in tube boilers. These boilers contain steam drum at top and water/mud drum at bottom. These two portions connected with the tubes some of which extend to the fire box envelope. The total design capacity of each boiler is about 45,000 lbs/hr of steam @ 20 kg/cm2 pressure. Now-a-days boilers are producing the steam from 45,000 lbs/hr to 55,000 lbs/hr and ion emergency ~ 90,000 lbs/hr @ 19.5 Kg/cm2.
FEED WATER FOR BOILERS:The water from KDA contains various TDS & TSS which can cause scaling in the tubes of boilers and it can decrease the heat transfer which cause increase in fuel consumption. So the water should be treated to remove its hardness before supplied to boilers. The water from KDA contains various TDS & TSS which can cause scaling in the tubes of boilers and it can decrease the heat transfer which cause increase in fuel consumption. So the water should be treated to remove its hardness before supplied to boilers.
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report
This treatment is carried out by the cat and base unit which exchange the ions of Ca+2 from water and this water send to deaerator to remove O2. Then water from deaerator enters into boilers at 129OC and at 1.7Kg/cm2.
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report ELCTRICITY GENERATION UNIT
The takes
the
refinery
electricity
from
KESC through BS-I (Korangi Thermal
Unit)
&
BS-II
(Qayoomabad Grid Station). The vital load on BS-I.
In case of failure of supply there is a new generator of Cummins C2500 D5A Diesel Genset and can produce 2250 kVA. Its standby is old Generator
of English Elctric with capacity of
1375kVA which was installed in 1962. Moreover there are two more generators of 630 kVA and 12.5 kVA which are used for lighting purpose.
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Internship Report WASTEWATER TREATMENT PLANT Ø Introduction:In
2004
a
second
industrial
waste
water
treatment
plant
established in Pakistan by Siemens in the premises of Pakistan
Refinery
Ltd.,
Karachi. The wastewater of PRL contains sulphides, chlorides, TDS oil and grease etc. they must be removed before discharging the water to the sea.
Ø Treatment 1.
The wastewater enters into the oil separator, where oil and grease skimmed from the water.
2.
Then water enters to the holding basin where remaining oil also removed from water.
3.
Then wastewater enters to the buffer tank where its pH maintained between 8.0 to 8.5.
4.
Buffer Tank (Tank – 42) removes the H2S by the aeration and release it to the atmosphere.
5.
Now Wastewater enters into Coiled Pipe Flocculating (CPF) unit where alum (35% w/v) and poly electrolytes (0.1% – 0.5% w/v) and is added.
6.
In CPF pH should be maintain b/w 6.8 to 7.8 by adding HCl and Caustic. a.
When pH drops to 6.8 caustic injection starts
b.
When pH reaches 7.8 HCl injection starts
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report 7.
Alum changes the surface characteristics of small particles of sludge and they attached with each other and settled down as coagulates.
8.
Small particles which can’t be coagulated by alum are separated by Poly electrolytes.
9.
Now the wastewater goes into the Title Plate Floatation unit where the suspended solids are floated over the surface by the air blowing from the bottom.
10. Wastewater then goes to Pre-Selector 2 where MLSs and MLVSs added to it and then it goes to oxidation basin where MLSS and MLVSs oxidized the organic matter ion the water. 11. In oxidation basin aeration automatically starts at D.O level 1.8 and stops at D.O level 2.5. 12. The feed for Microorganisms are FeCl3 and H3PO4. 13. Now the WW goes to knockout pit and then goes to clarifier pit and discharge to sea.
Created by: Hafiz Muhammad Junaid (08-07-2008)
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Internship Report TREATED EFFLUENT QUALITY Parameter
Value
pH
7 – 8.5
TSS
< 30ppm
Temperature
30 – 35OC
Oil and Grease < 0.1ppm Sulphides
< 0.1ppm
BOD5
<5ppm
COD
< 50ppm
Phenol
<0.05ppm
PRL EFFLUENT NORMAL VALUE Parameter
Value
pH
8.5 – 9.5
TSS
50
Temperature
30OC
Oil and Grease 10 – 20 ppm Sulphides
13 ppm
BOD5
12 ppm
COD
450 ppm
Phenol
1 – 7 ppm
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