1
TRAINING REPORT
@
SUPERVISOR
:
By:
Mr. Pramod Kumar
Bhardwaj Uday Umakant
SPM, IOCL
Mathura
2
INDEX
1. Acknowledgement
2. Synopsis
3. Brief Overview of IOCL
4. Overview of Mathura Refinery
5. Fire Risk Management Philosophy
6. Once-through Hydro Cracking Unit
7. New Hydrogen Generation Unit (NHGU)
8. Diesel Hydro Desulfurization Unit (DHDS)
9. Diesel Hydro-Treatment Unit (DHDT)
10. Jindal Coating Unit Report
11. References
3
ACKNOWLEDGMENT
We feel immense pleasure and privilege to express our deep sense of gratitude, indebtedness
and thankfulness towards MR. PRAMOD KUMAR & MR. SUSHANT ACHARYA who generously helped
us color the mosaic of this training with their knowledge, expertise and memories. We shall remain
ever grateful to all the persons of I.O.C.L, who have helped, inspired and encouraged us and above all
made us an ever more experienced person.
For their invaluable guidance, kind cooperation, inspiration and encouragement during all the
stages of our training, we would like to thank MR. GAURAV BAJAJ who has been of immense help
during our training period and thousands of other I.O.C.L employees whose name we could not
mention just for the lack of space. Last but not least, we would like to convey our hearty and blossom
thanks to my friends and fellow mates who have directly or indirectly helped me in the compilation of
this report.
After the completion of the training program, we found it to be of immense help, not only in
supplementing the theoretical knowledge, but also by gaining highly practical knowledge regarding
the actual work carried out in a Refinery Plant. At the end, we again express our gratitude to all those
who helped us in any way to complete our project work successfully.
June 2013
4
Overview of Indian Oil
I.O.C.L: AN OVERVIEW
Introduction
Indian Oil Company Limited, a wholly owned Government company was incorporated on 30 June, 1959 to undertake marketing functions of petroleum products. Later, Indian Oil Corporation Limited (IOC) was set up on 1st September,
1964 by amalgamating the Indian Refineries Limited (started in August, 1958) with the Indian Oil Company Ltd., for better coordination between refineries and marketing.
5
Indian Oil Corporation Limited or IOC is India’s largest commercial enterprise and the only Indian company to be among the world’s top 200 corporations according to Fortune magazine. It is also among the 20 largest petroleum companies in the world.
It was established in 1959 as Indian Oil Company Limited which was merged with Indian Refineries Limited in 1964 to form IOC as it is today.
Indian Oil Corporation has four divisions:
Marketing Division with Headquarters at Bombay;
Refineries and Pipelines Division with Headquarters at New Delhi;
Assam Oil Division with Headquarters at Digboi; and
Research and Development Centre at Faridabad.
The Assam Oil Division was established on 14th October, 1981 on taking over the refining and marketing operations of Assam Oil Company Limited.
The Company wholly owns a subsidiary Company viz. Indian Oil Blending Limited, which is engaged in the manufacture of lubricants and greases. The products of the subsidiary Company are also marketed by the Company.
Objectives
The objectives of the Company as approved (June, 1984) by Government are as follows:
To serve the national interests in the oil and related sectors in accordance and consistent with Government policies.
To ensure and maintain continuous and smooth supplies of petroleum products by way of crude refining, transportation and marketing activities and to provide appropriate assistance to the consumer to conserve and use petroleum products most efficiently.
To earn a reasonable rate of return on investment.
To work towards the achievement of self-sufficiency in the field of oil refining, by setting up adequate domestic capacity and to build up expertise for pipe laying for crude/petroleum products.
To create a strong research and development base in the field of oil refining and stimulate the development of new petroleum products formulations with a view to eliminate their imports, if any and
6
Decentralisation of Imports And Exports
Earlier, import of crude oil and import as well as export of almost all petroleum products were done through the Company. In the wake of economic liberalisation, the Government has decentralised a number of petroleum products starting from July, 1991. The Govt. of India amended (July, 1994) Export and Import Policy 1992 -1997, thereby enabling the users to import ATF (Aviation Turbine Fuel) against special import licence. The Company assisted (October, 1994) the airlines in importing the ATF. But with imposition (March, 1995) of a cost and freight surcharge by Government with retrospective effect, the Company stopped such imports as these were no longer beneficial. By September, 1995 as many as 9 products, including LPG and Kerosene, which are being marketed in parallel by joint as well as private sector, have been decentralised and custom duties on them have also been successively reduced. A chronology of major events in the decentralisation of marketing of petroleum products is given at Annexure-I.
However, the Company continues to import LPG and Kerosene for meeting the country’s demand and for sale through public distribution system at administered and centralized prices.
Organizational Set-Up and Network of Marketing Division
The Marketing Division, with its headquarters at Bombay and headed by Director (Marketing), has four regional offices located at Bombay, Delhi, Calcutta and Madras. All regional offices are headed by either Executive Directors or General Managers. There are 44 Divisional Offices, including two of the Assam Oil Division. As on 31 March, 1995, the Company had 39 bulk storage installations (including 3 of AOD) and 117 storage depots, which fed 5995 retail outlets. In addition, there were 2898 kerosene/light diesel oil dealers who also move these products from the depots to 4379 consumer outlets for sale. The Company had a total product tankage of 3.93 million kilo liters at its installations and depots.
Being the major producer and distributor of LPG to various types of consumers in India, the Company has 32 area offices to deal with LPG marketing. As on 31 March, 1995, the Company had 33 LPG bottling plants with a total bottling capacity of 11.92 lakh tones per annum. Indane cooking gas (LPG) is distributed to 12 million households.
Indian Oil markets nearly 66.8 percent of the country’s aviation fuel (68.2% in 1992-93), meeting the needs of 59 international airlines besides the domestic carriers and the defence services. Of the 117 aviation fuel stations in the country, Indian Oil operates 93.
7
Products
Auto LPG
Aviation Turbine Fuel (ATF)
Bitumen
High Speed Fuel
Industrial Fuels
Liquefied Petroleum Gas
Lubricants and Greases
Marine Fuels MS/Gasoline Petrochemicals
Services
Refining Pipelines Marketing Training
8
Location of various I.O.C Refineries
IOC Refineries - Overview
Refinery Year of Commissioning Initial Capacity TMTPA Capacity, TMTPA As on 01.04.06 Digboi 1901 28 650 Guwahati 1961 750 1000 Barauni 1964 2000 6000 Gujarat 1965 2000 13700 Haldia 1975 2500 6000 Mathura 1982 6000 8000 Panipat 1998 6000 6000 IOC's Total 41350 IOC Associates 12850 IOC+Associates 54200 Total Industry 132470 % Share (IOC) 41%
IOCL Refineries
Guwahati 1.0 Koyali :13.7 Kandla Viramgam Digboi 0.65 Salaya Chaksu Haldia : 6.0 Barauni : 6.0Refinery Capacity in MMTPA
Mathura: 8.0 Panipat: 6.0
CBR : 1.0 CPCL-M :9.5
Oil India Crude Pipeline SMPL HBCPL BRPL:2.35 IOC Refineries IOC Associates Mundra Sanganer Sidhpur KBPL Conversion Paradip : 15.0 New Crude PL
9
Mathura Refinery: An Overview
Introduction
Mathura refinery was commissioned in 1982 as the sixth refinery in the fold of IndianOil and with an original capacity of 6.0 MMTPA. Located strategically between the historic cities of Delhi and Agra, the Refinery at Mathura is situated in the mythical and mystical land of Lord Krishna. Later the capacity of Mathura refinery was increased to 7.5 MMTPA by systematically debottlenecking and revamping. With its Fluid Catalytic Cracking Units (FCCU), the refinery mainly produces middle distillates for Northern India supplied though a 760km long product pipeline to Jalandhar in Punjab via Delhi (MJPL) and 100km long Mathura Tundla Pipeline (MTPL). A Vis-breaking unit was commissioned in 1982 and Soaker drum technology was implemented in VBU in the year 1993. The two-stage desalter was commissioned in 1998 in order to improve the on-stream availability of the crude distillation unit. In the same year new Continuous Catalytic Reformer Unit (CCRU) for production of unleaded gasoline was added.
The First hydrogen generation unit (HGU-I) commissioned in 1999 along with first Diesel Hydro-desulfurisation unit (DHDS) for production of HSD with a low Sulfur content of 0.25% wt (max). A once through Hydro-cracker unit was commissioned in July’ 2000 for increased middle distillates production. For supplying EURO-III grade auto fuels, viz, EURO-III HSD and EURO-III MS to National Capital Territory (NCT) and National Capital Region (NCR), a Diesel Hydro-treating unit (DHDT) and MS quality up gradation unit consists of NHDT and PENEX along with FCCU Gasoline splitter and 2nd Hydrogen generation unit (HGU-II) commissioned in 2005. The present capacity of the refinery is 8.0 MMTPA and regularly receives crude oil through the 1870 km long Salaya Mathura Pipeline (SMPL). Over the years Mathura Refinery has systematically synchronized technology with ecology with constant care for the surrounding environment. Its close proximity to the magnificent wonder TajMahal adds to the responsibility towards a cleaner Environment.
Salient Features :-
1. The Refinery processes low sulphur crudes from Bombay High, Nigeria, and high sulphur crudes from Middle
East Countries. The process configuration of the Refinery employs the state-of-the-art technologies with minimal impact on the environment.
Various steps have been taken by Mathura Refinery to monitor and control the emission of Sulphur Dioxide. Mathura Refinery is the only refinery in the country to have set up the concern of community and archeological
10 sites. These Ambient Air Monitoring Stations were commissioned before commissioning of the Refinery in 1981 and being continuously operated thereafter.
2. Mathura Refinery has taken many initiatives to produce more and more clean fuels in stages in the interest of
environment, public health and preservation of national monuments around. Its noteworthy efforts are stage-wise implementation of various projects like Catalytic Reforming Unit, Diesel Hydro-desulphurisation Unit and Hydrocracker for quality upgradation of automobile fuels.
3. The Refinery has full-fledged ETP comprising of physical, chemical and biological treatment facilities. The treated
effluent from the Refinery fully meets the MINAS(Minimal National Standards), the prescribes effluent discharge standards
4. For the protection of the land environment, Mathura Refinery has initiated biodegradation of oily sludge
through "Oilivorous-S", an oily sludge degrading bacterial consortium developed by IOCL(R&D) in collaboration with Tata Energy Research Institute.
5. The Refinery has full-fledged ETP comprising of physical, chemical and biological treatment facilities. The treated
effluent from the Refinery fully meets the MINAS(Minimal National Standards), the prescribes effluent discharge standards
6. A beautiful ecological park has been developed in an area of 4.45 acres. During the recent survey, the experts
from the BNHS (Bombay Natural History Society) have identified 96 species of birds of which 30 migratory ones in the park giving a testimony of richness of life in the ecosystem.
7. Mathura Refinery has done extensive tree plantation in and around Refinery. The Refinery has also taken
extra-ordinary initiatives to provide green cover to the archeological heritage sites especially the TajMahal by planting 1,15,000 trees in the Taj region.
11
Awards/Accolades:-
Safety:
Mathura Refinery received the prestigious Oil Industry Safety Award 2008-09 for Best Overall Safety Performance
among Refineries. Shri J.P. Guharay, ED Mathura Refinery received the award from Shri Murli Deora, Minister of Petroleum and Natural Gas at a glittering function held in Oct’ 09 at Delhi.
Mathura Refinery received Gold Award in Petroleum Refinery sector from Greentech Foundation, New Delhi, for outstanding achievement in Safety Management in 2008. The award was presented by Shri R.K. Srivastava,
Director General, Ministry of Health & Family Welfare, Govt. of India, New Delhi on 4th May 2009 at Goa.
Received British Safety Council Award’08 in May’09 for excellence in Health, Safety and Environment Management.
Received Safety Innovation Commendation-2009 award from Institution of Engineers in Sep’09 for innovation in
Safety for 2008-09.
Security:
Received Best Corporate Security Trophy (Refinery Category) for two consecutive years i.e. 2008 & 2009.
Energy Conservation:
Mathura Refinery received First Prize of 'Oil and Gas Conservation Fortnight -2009' for lowest Steam
Consumption Performance amongst Refineries having steam consumption <= 0.5 MT/MT and same was received by ED, MR during 15th RTM at Mahabalipuram on 5th Nov.’09.
Received 'Jawharlal Nehru Centenary Award 2008-09' - second prize for Specific Energy Consumption Performance amongst all refineries in the public sector. ED, MR received coveted award during 15th RTM held at Mahabalipuram on 5th Nov-09.
Environment:
Received ‘Gold Award-2009’ from Greentech Foundation for outstanding achievement in Environment Management in Oct’09.
12
Financial:
Received the “SammaanPatra” for the year 2009-10 in the category of Large Scale Units, by Central Excise Deptt,
Lucknow Circle in recognition of the highest levels of compliance with regard to Indirect Taxes apart from contribution to the exchequer. The trophy was received by GM(F)-MR at Lucknow on 24th February, 2010.
TPM:
Mathura Refinery TPM health checkup was carried out by CII on 23rd December’09 thereby approving the
nomination of Mathura Refinery for final audit on Excellency Certification in TPM activities by JIPM.
Propylene bulk truck loading facility completely shifted to new location outside refinery premises at Marketing Terminal in Oct’09.
In land matters, the search certificates as well as Non-encumbrance Certificates for 1199.49 acres of land of
Mathura Refinery received from District Revenue Officer. The UP Govt has also provided the NOC for 1199.49 acres of land enabling appropriate mortgage with State Bank of India.
70 cases with Customs were settled and refund of Rs 55.12 crores received from Customs Department in Mar’10.
Various PFIs of Business Improvement Program with M/s Shell Global were successfully implemented.
Major facilities commissioned:-
PRIME-G unit: PRIME-G unit for FCC gasoline desulphurization was successfully commissioned on 20th Feb 2010. BBU Revamp: Biturox Technology was implemented in BBU in Oct’ 09. The capacity of the Bitumen unit was
increased from 0.5 MMTPA to 0.75 MMTPA.
ATF Tank: New 10000 KL capacity ATF tank was mechanically completed and commissioned in March. This
additional tank will facilitate supplying higher ATF parcel size and will help in tapping additional ATF production potential.
NG as HGU Feed: Facilities (2.4 Km 10” line, Knock out Drum, LP steam heater, associated control valve and
piping) for use of high pressure Natural Gas feed to HGUs were completed at refinery end.
Simultaneous pumping of HSD in MJPL & MTPL: A dedicated header for simultaneous pumping BS-III HSD in
13
Additional DM plant chain: Fourth chain of DM plant was mechanically completed. Commissioning of additional
chain will ensure sustainable and reliable operation of DM plant.
Process Schemes for Euro-IV preparedness: Six nos of process schemes were implemented to ensure availability
of Euro-IV products as per schedule.
Units :
PROCESSING UNITS OF MATHURA REFINERY
S.No. Name of Processing Units
1 Atmospheric & Vacuum Distillation Unit(AVU )
2 Visbreaker Unit (VBU)
3 Fluidized Catalytic Cracking Unit (FCCU)
4 Continuous Catalytic Reforming Unit (CCRU)
5 Propylene Recovery Unit (PRU)
6 Hydrogen Generation Unit ( HGU )
7 Once Through Hydrocracker Unit (OHCU)
8 Sulphur Recovery Unit (SRU)
9 Bitumen Blowing Unit (BBU)
10 Diesel Hydro Desulphurization Unit (DHDS)
11 Merox (Mercaptan Oxidation)
The refinery runs on a large number of predominantly Middle East crude. For refinery producing lube oil base stacks, it is highly unusual to run so large number of crude because the operation of the lube oil process is highly crude specific. It is more usual for a lube refinery to operate on a handful of selected feed stacks and to operate the lube units based upon the known processing characteristics and response of the crude oil. This is not possible at MATHURA
14 refinery due to the large number of crudes handled and on the constraints on the size of the crude percels that can be handled through the port.
Products:
Finished products from this refinery cover both fuel oil products as well as lube oil base stocks. 1. Liquid Petroleum Gas (LPG)
2. Fuel Oil Products:
Motor Spirit (MS)
Mineral Turpentine Oil (MTO)
Superior Kerosene (SK)
Aviation Turbine Fuel (ATF)
Russian Turbine Fuel (RTF)
High Speed Diesel (HSD)
Jute Batching Oil (JBO)
Furnace Oil (FO)
Naphtha
Gasoline 3. Lube Oil Products:
Inter Neutral, Heavy Neutral & Bright Neutral HVI Grades 4. Other Products:
Slack Wax
Carbon Black Feed Stock
Bitumen
Sulphur
Future:
With Indian oil’s achievement of a high degree self-reliance defining technology, Mathura refinery is poised for a bright future. All out action have taken for capacity augmentation, increase in distillate production, value addition, cost reduction for obtaining higher margins and improving productivity. All environmental friendly products with latest technology is being incorporated to meet the challenge of change. Mathura refinery will continue to play a significant role in meeting the vital needs of petroleum products in the country.
15
Fire Risk Management Philosophy
Petroleum refinery which stores and handles large quantity of flammable materials pose threat to the surrounding in addition to its own safety. It therefore, necessitates the introduction of inbuilt fire prevention & fire protection facilities.
It is impractical and prohibitively costly to design fire protection facilities to control all catastrophic fires. Usual requirement of a good system is to prevent emergencies from developing into major threat to the installations and surroundings.
Fire
Fire is a rapid, self-sustained oxidation process accompanied by the release of energy in the form of heat and light of varying intensity.
Fire results from the combination of fuel, heat and oxygen. When a substance is heated to a certain temperature called the ‘ignition temperature’ the material will ignite and continue to burn as long as there is fuel, the proper temperature and a supply of oxygen (air).
Fire Triangle
Three elements are necessary for initiation of fire: 1. Fuel in the form of vapour, liquid or solid.
2. A source of ignition sufficient to initiate & propagate the fire. 3. Oxygen in sufficient proportion to form a combustible mixture. Combustion process is observed in two modes.
For flaming combustion to occur, solid or liquid fuel must be converted into a vapor, which then mixes air and reacts with oxygen.
Smoldering combustion, on the other hand, involves a reaction between oxygen and the surface of the fuel: this is a
16 FIRE TRIANGLE OXYGEN HEAT FUEL
Classification of Fire
An Indian standard IS: 2190 classifies the fire in four categories according to the type of material burning.
Class A: Fires involving ordinary combustible material like wood, paper, textiles etc. where the cooling effect of water is
essential for extinguishments of fire.
Extinguishing media- water
Class B: Fires in flammable liquids like oils, solvents, petroleum products, paints etc. where a blanketing effect is
essential to extinguish the fire.
17
Class C: Fires involving gases or liquefied gases in the form of a liquid spillage, or a liquid or gas leak. Here it is necessary
to dilute the burning gas at a very fast rate with an inert gas or powder.
Extinguishing media - carbon dioxide, dry chemical powder. The best way to extinguish such fires is by stopping the flow
of fuel gas to fire. Container is kept cool with water spray.
Class D: Fires involving metals like magnesium, aluminum, zinc, potassium etc. Where the burning metal is reactive to
water and which require special extinguishing media.
Extinguishing media- Special dry powder.
Electrical fire : Electrical fires are not treated as a class of their own, since any fire involving, or started by, electrical
equipment must, in fact, fall into one of the other categories.
The normal procedure for dealing with an electrical fire is to cut off electricity and use an extinguishing media appropriate to what is burning.
Classification of Petroleum Products
Class –A: Liquid which have flash point below 23oC.
Class –B: Liquids which have flash point of 23oC and above but below 65oC
Class –C: Liquid which have flash point of 65oC and above but below 93oC
Excluded Petroleum: Liquid which have flash point of 93oC and above.
Note: LPG do not fall under this classification but form separate category.
Definitions:
Hazard: Situation with a potential for damage to men, machines and environment.
Ex : Fire / explosion in LPG storage : Toxicity in chlorine storage
Risk : Combination of hazard consequence and its probability of occurrence.
18
Flash point: The flash point of a liquid is the lowest temperature at which sufficient vapour given off to flash on the
application of flame in the presence of air.
Auto – ignition: The lowest temperature to which a solid, liquid or gas requires to be raised to cause self-sustained
combustion without initiation by a spark or flame.
Explosive limits: Explosive limits are those concentrations of a vapor or gas in air below or above which propagation of a
flame does not occur on contact with a source of ignition.
The lower explosive limit is the minimum concentration below which the vapor air mixture is too lean to burn or explode.
The upper explosive limit is the maximum concentration above which the vapor air mixture is too rich to burn or explode.
Methods of Extinguishments of Fire
1. Starvation : Elimination of fuel 2. Smothering : Limiting of oxygen 3. Cooling : Limiting temperature
Starvation: Starvation is accomplished by removing combustibles from the neighbourhood of the fire or by removing fire
form the mass of combustible materials. It is also achieved by subdividing burning materials to small isolated pockets of fire.
Smothering: Smothering is accomplished by eliminating or diluting the available oxygen with inert gas or covering the
fuel surface by a smothering agent like foam.
Cooling: If the rate at which heat is generated by combustion is less than the rate at which it is getting dissipated then
the combustion cannot persist. Application of water jet or spray to a fire results in its extinguishments by this fundamental principle
19 CLASS
OF FIRE
DESCRIPTION EXTINGUISHING MEDIUM INDIAN
STANDARD
A Fire involving ordinary combustible materials like wood, paper, textiles, etc. Where the cooling effect of water is essential for the extinction of fires
Water 934-1976
940-1976 6234-1971
B Fire inflammable liquids like oils, solvents, petroleum products, varnishes, paints etc. where a blanketing effect is essential
Foam * carbon dioxide dry chemical powder. Not suitable for alcohol and other water miscible flammable liquids
933-1976 2878-1976 2171-1976 (4308)-1982
C Fires involving gaseous substances under pressure where it is necessary to dilute the burning gas at a very fast rate with an inert gas or powder.
Carbon dioxide dry chemical powder. The best way to extinguish such fires is by stopping the flow of fuel gas to the fire. Container is kept cool with water spray
2878-1976 2171-1976 (4308)-1982
D Fires involving metals like magnesium, aluminum, zinc, potassium etc. where the burning metal is reactive to water and which require special extinguisher media.
Special dry powder 2171-1976 (4861) – 1968
20
Source of Ignition
It is necessary to understand the sources of ignition and to eliminate them to prevent fires/explosions in the refinery.
SOURCES OF IGNITION EXAMPLE PREVENTIVE MEASURES
Electrical equipment Sparks from motors, switches, lamps, hot elements and electrical defects
1. Use of approved equipment
2. Follow nation electrical codes
3. Proper maintenance.
Friction Hot bearings, misaligned or
broken M/C parts, chocking, jamming of material, poor adjustment
Preventive maintenance and proper lubrication
Open flames Cutting and welding torches gas & oil burners
Strict compliance of precautions stipulated in the fire permit for hot jobs.
Smoking as ignition Smoking booths in area where combustible are used
1. Smoking only in areas permitted.
2. Use of prescribed receptacles for cigarette butts
Spontaneous ignition Pyrophoric iron, hot oil leakage
Keep pyrophoric iron wet at the time when it is taken out.
Hot surfaces Contact of combustible
material without surfaces, heated lines
Provide proper insulation and air circulation.
21 Spark from engine exhaust POL trucks / DG set Spark arrestor on exhaust
Static electricity During splash loading and loading at high velocities
1. Proper earthing of equipment.
2. Loading velocity should be controlled
Lightening Thunderstorm cloud burst Proper lighting arrestor and earth continuity.
Fire Risk Management
Fire risk is ‘the chance / possibility of loss due to fire’. Three aspects to deal with fire risk management are: • Fire prevention
• Fire protection • Fire fighting
Fire Prevention
Objective: To eliminate the occurrence of fire
Regulations for the prevention of fire
Fire & explosion contribute a serious hazard to hydrocarbon processing industry like a petroleum refinery. The following regulations should be strictly followed for prevention of fire.
Regulation – 1:
Fire or naked light, matches, petrol or other lighters, cellular phone or any apparatus which is capable of causing ignition is not permitted to be taken within the battery area by any person.
Regulation – 2
No fires shall be lit and no matches ignited in any part of the battery area unless a valid hot work permit has been obtained from the authorised fire permit signatories of the area and registered at the fire station
22
Regulation-3
Smoking is prohibited in all parts of the battery area except in the smoking booths/locations duly approved for this purpose.
Regulation – 4
Cycle lamps, other than dynamo operated, are not allowed in the refinery battery limits. The cyclist will switch off even the dynamo as soon as he enters the plant area.
Ordinary torches will not be used within the battery area. Flame proof torches/lamps of approved manufacturers as supplied by the refinery, shall only be used.
Regulation-5
All vehicles entering / transporting petroleum products from the refinery must be fitted only with approved type of spark arrestors.
Regulation-6
Persons entering the refinery battery limit shall deposit match boxes, lighters, mobiles etc with the security at the main entrance gate of the refinery.
Fire Protection
Objective: To contain the spread of fire
Fire protection philosophy:
Fire protection philosophy is based on loss prevention & control. Because of the inherent hazard a refinery carries. No plant is absolutely safe. A fire in one part/section of a plant can endanger other sections of plant as well.
Types:
• Active Fire Protection System • Passive Fire Protection System
Following fire protection facilities shall be provided depending on the nature of the installation and risk involved: • Fire Water System
23 • Clean Agent System
• CO2 System
• DCP Extinguishing System • Detection And Alarm System • Communication System
Fire Fighting
Objective: To extinguish the fire with minimum loss
It is the last line of the defense. It comes into force when there is actual fire. Main purpose is to extinguish the fire with suitable equipment and materials with an aim to reduce damage due to fire
• Portable fire fighting equipment • Mobile fire fighting equipment • Fixed fire fighting system
Mobile Fire Fighting Equipment
• DCP tenders • Foam nurser • Trailer fire pump
• Trolley mounted monitors
• Fire fighting hose & other accessories like foam branch, nozzles etc. • Fire fighting chemicals like foam compound, dry chemical powder etc.
NEED FOR SAFETY
ECONOMIC ASPECTS • LOSS OF PRODUCTION • LOSS OF CAPITAL • LOSS OF MANPOW ER • MEDICAL COMPENSATION • COST OF TRAINING • LOSS OF WAGES • BUSINESS INTERRUPTIONS LEGAL ASPECTS (STATUTORY OBLIGATION) HUMAN ASPECTS • PHYSICAL INJURY • REPARATION ON FAMILY • MORAL LOSS SOCIAL ASPECTS • GENETIC • ECOLOGICAL • LOSS TO NATION • POLLUTION OF STREAM AND AIR
24
Safety Aspects
Safety, Health & Environment (S, H&E) Policy
Indian Oil Corporation is committed to conduct business with strong environment conscience ensuring sustainable development, safe workplaces and enrichment of quality of life of employees, customers and the community. We at Indian Oil believe that good safety, health & environment performance is integral part of efficient andprofitable business management.
We shall:
• Establish and maintain good standards for safety of the people, the processes and the assets. • Comply with all rules and regulations on safety, occupational health and environment protection.
• Plan, design, operate and maintain all facilities, processes and procedures to secure sustained safety, health and environmental protection.
• Remain trained, equipped and ready for effective and prompt response to accidents and emergencies.
• Welcome audit of our safety, health & environment conduct by external body, so that stakeholder confidence is safeguarded.
• Adopt and promote industry best practices to avert accidents and improve our safety, health & environment performance.
• Remain committed to be a leader in safety, occupational health and environment protection through continuing improvement.
• Make efforts to preserve ecological balance and heritage.
General Loss Control Rules
• No match box/ lighter / mobile is allowed in refinery.
• No smoking is allowed in refinery except at designated places. • No vehicle is allowed inside battery area without spark arrestor. • No body is allowed to enter the refinery without shoes.
• No outsider is allowed inside any operational plant / unit area without permission of area in charge. • No debris/obstacles allowed on roads.
• No photography / videography is allowed without permission.
• No maintenance work should be started without valid permit & clearance. • Never enter work area without helmet with chin strap in place.
25 • No climbing/working allowed without safety belt above 2 metre height.
• Do not walk on pipelines or false ceilings. • Do not stand under suspended loads.
• Do not tamper with fire fighting equipment or fire hydrants. • Do not exceed speed limit of 25 kmph within the refinery premises. • Report all accidents/incidents to area incharge and fire & safety.
26
Once-through Hydro Cracking Unit
Basic Details
Design capacity 1.2 MMTPA
Turn down capacity 50% of design
Licensor CHEVRON Research and Technology
Purpose of Unit:-
MR from its inception in 1981 has been proceeding the crude oil which are classified primarily in two categories. i. Low sulphur crude oil
ii. High sulphur crude oil
Residue up gradation into middle distillates and light distillates is currently being done in MR primarily by employing FCC process, and visbreaking.
Visbreaking is adopted to reduce the viscosity of residues thereby making it marketable. Viscosity of products obtained from FCC and Visbreaker are relatively poor in quality w.r.t. stability, and sulphur have to be blended with other straight run product to be able market them.
Hydrocracker Technology:-
It is an extremely versatile catalytic process in which feed ranging from naphtha to vacuum residue can be processed in presence of H2 and catalyst to produce desire products lighter than the feed. Thus if the feed is naphtha it
can be converted to LPG. In MR VGO (vacuum gas oil) is feed and products are LPG, naphtha, ATF, diesel and FCCU feed. Feed to the unit consists of VGO from AVU (Atmospheric Vacuum distillation Unit) containing 70% high sulphur and 30% low sulphur.
Hydrocracker unit consists of four following section Make up H2 compression section
Reaction section Fractionation section Light end recovery section
Primary products from OHCU:-
LPG: - It is separated from light naphtha from stabilizer located in the light end section of the unit. LPG is treated with caustic to remove H2S and free water to meet sales specifications.
27 Stabilized light naphtha:- It is the bottom product of stabilizer with nominal true boiling point(TBP) cut point
range for light naphtha used in this design is C5-1080C, stabilized light naphtha sent to tankage after cooling.
Heavy naphtha:-It is recovered as the first side cut of atmospheric fractionator. This draw is sent to heavy naphtha side cut stripper. The nominal TBP cut point range for heavy naphtha is 108-1270C. After leaving the side cut stripper heavy naphtha is sent to either tankage off plot or blended into diesel product upto 380C in diesel flash point specification.
ATF/Superior Kerosene: - It is recovered as the second side cut of atmospheric fractionator. This draw is sent to kerosene side cut stripper. The nominal TBP cut point range of Kerosene is 127-2570C. After leaving the side cut stripper kerosene is cooled and may either sent to tankage or blended into diesel products.
High speed diesel (HSD):-It is recovered as the third draw of product fractionator. This draw is split between pump around liquid and feed to diesel side stripper. The diesel pump around stream provides rebioling for heavy naphtha and kerosene side stripper and the de-ethaniser and stabilizer. The nominal TBP is 257-3000C. The diesel product from side cut stripper is first cooled and blended with heavy naphtha and kerosene to meet product requirement.
FCC feed:-It is the bottom product of atmospheric fractionator.
In reactor section feed is combined with H2 at high T & P and this is catalytically converted into Higher transportation
feed. The makeup H2 compression section provides H2 to reactor section. The reaction products are separated and
cooled in the H2 rich recycle gas is scrubbed using DEA in H2S absorber to remove H2S.
HCU operates under two different catalytic conditions:- i. Start of Run(SOR)
ii. End of Run(EOR)
When the catalyst is new or freshly regenerated, it is start of run condition. The catalyst gets deactivated due to coke deposition and requires regeneration to operate under design stipulations. The operating condition just before the regeneration is called EOR operation.
Catalyst type:-
The lead and the main reactor contains ICR 126, a highly active and stable catalyst at high conversion levels. ICR 126 is an amorphous catalyst with a small % of zeolite.(middle distillate yield is not overly sacrificed)
ICR 114L is loaded in the bottom bed of the main reactor for merceptane control. With cracking catalysts, there is equilibrium between intermediaries in the cracking reaction on H2S to form merceptanes. It is relatively inactive for
conversion, it only desulphurises. Thus ICR 114L shifts merceptanes formed by cracking catalyst to desulphurise HC and H2S.
ICR 114ZF is used in the bottom of each bed of both reactors. It is not cracking catalyst and much larger in size than the cracking catalysts.
28
Effect of condition:-
S.No. Variable Change Effect on catalyst life
1 Feed Rate Increase Decrease
2 Conversion Increase Decrease
3 H2 partial pressure Increase Increase
4 Make up gas purity Increase Increase
5 Reactor pressure Increase Increase
6 Recycle gas rate Increase Increase
7 Recycle gas purity Increase Increase
Process Description:-
In hydrocracker, the VGO feed is subjected to cracking in a reactor over catalyst bed in presence of H2 at pressure of 185
kg/cm2 and temperature ranging from 365-445 0C. Cracks products are separated in fractionator. Light ends are recovered in de-butaniser column. The process removes almost all sulphur and nitrogen from feed by converting into H2S and NH3 except from mild caustic wash for LPG, post treatment is not required for other products. The unit consists
of four sections
Hydrocracker is made up of four sections:-
i. Reactor section:- Feed stoke is mixed with H2 at high temperature and pressure in the presence of catalyst,
converted to lighter transportation fuel. It consists of two reactors in series, lead reactor (3 catalyst bed, pressure 189 kg/cm2) and main reactor (2 catalyst bed), due to high weight of catalyst (400MT).
The hydro treating and hydro cracking reaction taking place in reaction stage at high T & P. The high partial pressure of H2 taken to prevent coking of catalyst and excess H2 is recirculated in reactor top for cooling
and to promote hydro cracking reaction. In the lead and the main reactor fresh feed is partially converted to mild distillates and lighter products. S & N are almost completely removed or aromatic content is reduced. The reaction section contains additional equipment for separation of H2 rich gas from reactor effluents which is
compressed and recycles back to the high pressure reactor loop. The recycle gas contains H2 by product
generated from hydro cracking reaction, H2S and NH3. Nearly all ammonia and some of the H2S are removed in
form of ammonium bi sulphite by water that is injected upstream of the cold high pressure separator. H2S is
removed from reactor section in liquid form.
ii. Make Hydrogen compression section:-Provides H2 to reactor section. The H2 rich recycle gas is scrubbed with Di
Ethyl Amine (DEA) in H2S absorber to remove H2S. It consists of three parallel compressor trains each with 3
29 are also used to compress the mixture of N2 and air during catalyst regeneration. The compressed make up H2 is
combined with H2 recycle gas in the reactor section to form reactor feed gas.
iii. Fractionation section:-The purpose of this section is to separate the reactor section products into sour gas,
unstabilised liquid naphtha, heavy naphtha, kerosene and diesel. Bottoms containing and converted products are fed to FCC unit. The sour gas and unstabilised naphtha sent to light end section to make flue gas, LPG, light naphtha.
iv. Light end recovery section:-Liquid naphtha from fractionation section is sent to de-ethaniser, where H2S is
absorbed in amine and the H2S free fuel gas is sent to fuel gas system. The rich amine is sent to ARU (Amine
Regeneration Unit) in Sulphur Recovery Unit (SRU) block. The de-ethaniser bottom is sent to de-butaniser for recovery of LPG. LPG is taken out from the top of de-butaniser and sent to treating section where it is washed with caustic for removal of H2S.
The three main functions of this section are:-
Remove light ends and H2O from light naphtha
Separate LPG and treat LPG to desired specification Sweeten the sour gas for further uses as fuel gas
30
New Hydrogen Generation Unit (NHGU)
TECHNOLOGY : Technip,France CAPACITY : 65000 MTPA INTRODUCTION :
A New Hydrogen Generation Unit of 65000 metric tones per annum of Hydrogen producing is recently included in the secondary processing facilities. The primary objective of the Hydrogen Generation Unit is to produce hydrogen to meet the entire hydrogen requirement of Hydrocracker,Diesel Hydro Desulphurization Unit,Diesel Hydrotreatment Unit & the new upcoming project Motor Spirit Quality Upgradation Unit.
PROCESS DESCRIPTION :
1. FEED PRE-DESULPHURIZATION :
The feed contains unsaturated components as well as high amount of organic sulphur. Sulphur would act as a poison for the downstream process catalysts and needs to be removed. The bulk of the sulphur can be removed by conversion (hydrogenation) of the organic sulphur components to H2S and subsequent stripping.The feed to the unit is the straight run naptha which is passed through filters & collected in the sour naptha feed surge drum.The feed is mixed with hydrogen recycled from PSA & fed into the furnace through a series of heat exchangers.The temperature of the mixture is raised to 310-330 oC so the naptha gets vaporized.The superheated sour naphtha / H2 mixture is fed to the
hydrogenation reactor which consists of two layers of catalysts, with the top layer consisting of Nickel Molybdenum and the bottom layer consisting of Cobalt Molybdenum catalyst. In this reactor, the olefinic compounds in the feed naphtha get saturated and the sulphur in the naphtha gets converted to H2S. The chlorine present in the feed gets converted to HCI.The mixture coming from the reactor is cooled in heat exchangers & water coolers & sent to a separator having a pressure of 19 kg/cm2.The liquid naptha from the separator drum contains dissolved H2S is heated to 125 oC & sent in the stripper where the H2S is stripped off & naptha is taken as the bottom product.
RSH + H2 RH + H2S
RCI + H2 RH + HCI
31
2. FEED DESULPHURIZATION :
The sweet naphtha, collected in the sweet naphtha surge drum. This naphtha is pumped by the sweet naphtha feed pumps to a pressure of approximately 39 kg/cm2g.The feedstock is mixed with hydrogen under ratio control and preheated to about 120C in the heat recovery section.This feed is vapourized by HT shift effluent in the feed naphtha vaporizer and is superheated to about 380 C to 400 C in the convection coil.
This is now fed to the hydrogenation reactor to convert any residual organic sulphur to H2S.This reactor contains 4.5 m3
of CoMOx or any other equivalent catalyst.The recycle hydrogen is mixed to provide a mole ratio of 0.25 to provide the necessary amount of hydrogen for conversion of sulphur in the hydrogenation reactor.The hydrogenated feedstock is then passed through the feed desulphurizers A/B containing the chlorine guard and zinc oxide catalyst.Reactor A consists of a bed of 4.1 m3 of Chlorine guard Al2O3 followed by reactor B having 2.2 m3 of ZnO.H2S & HCl are absorbed according to the reactions given below.
Hydrogenation reactor : RSH + H2 RH + H2S Reactor A : Al2O3 + 6HCI 2AlCl3 + 3H2O Reactor B : ZnO + H2S ZnS + H2O 3. PREREFORMER :
The desulphurized feed is mixed with a controlled quantity of steam based on the calculated hydrocarbon weight flow and the required steam to feed ratio. There are two prereformers, one in operation and the second on standby. Each reformer is designed for a life of 12 months operation and consists of 5.9 m3 of Katalco 65-3R (Ni based catalyst). After heating to required temperature of 460C in the pre-reformer preheat coil 3, the gas is passed through the prereformer A/B which is operated adiabatically and will convert the naphtha to methane, carbon dioxide, carbon monoxide and hydrogen.This results in a feed, which can be further preheated to minimize the reformer duty. The steam to feed ratio varies from 3.0 to 2.4 to enable additional temperature control for inlet to the prereformer.The feed in the presence of steam reacts to a mixture of methane, carbon dioxide, carbon monoxide and hydrogen over a nickel based catalyst. These reactions take place in both the pre-reformer as well as the reformer. The principle reactions are:
32
CnHm + nH2O nCO + (½m + n) H2 - Heat
CO + H2O CO2 + H2 + Heat
The CO formed from these higher hydrocarbons will be partly converted to methane. For n=1 and m=4; this reaction is referred to as the ‘steam methane reforming reaction’, the reverse reaction is generally referred to as ‘ methanation reaction. The reversible conversion of methane with steam to CO and hydrogen is strongly favoured by a high temperature, low pressure and high steam quantity which is maintained in the reformer.
4. REFORMER :
In order to achieve a higher hydrogen yield from the feedstock, after the prereformer the methane is further converted in the reformer, which operates at a higher temperature.The reaction in the reformer is strongly endothermic so burners are provided in the reformer.Before superheating in the mixed preheat coil , additional steam is added to meet the required steam to carbon for the steam methane reformer which consists of 204 tubes, 12.2 m heated length arranged in 6 lanes each of 34 tubes. Each tube is filled with Katalco 25-4 and Katalco 57-4(Ni based catalyst) in the ratio of 40% : 60% of the heated tube length.The reformer is designed to operate at a steam to carbon of 2.75 mol/mol, which is achieved, by an overall steam to feed of 3.25 kg/kg.The steam to carbon ratio will be increased at lower capacities.The normal reformer inlet temperature is around 650 - 665 at 10. The gas is distributed over the reformer tubes where the reforming reactions take place and an outlet temperature of 880 - 885C is reached.Coking is prevented using excess of steam.
5. SHIFT REACTOR :
The gas mixture, which leaves the reformer, is essentially at equilibrium of the shift reaction. Since the equilibrium of the reaction shifts with the temperature, shift conversion will be applied at comparatively lower temperatures to further convert carbon monoxide to hydrogen. There are two temperature levels at which the reactors are operated. The first stage reactor is the High Temperature Shift Reactor and the other, Low Temperature Shift Reactor. The principle reaction is
CO + H2 CO2 + H2
Reactor inlet temperature of 327C fo. In order to increase the hydrogen content in the syngas from the reformer, the bulk of the carbon monoxide is converted by steam to hydrogen and carbon dioxide in the high temperature shift reactor 302-R-14 filled with 25.6 m3 of Katalco 71-5 catalyst. The reformer effluent is cooled to the required inlet temperature for the high temperature shift reactor in the process gas boiler.The effluent from the HT Shift Reactor is at a high temperature. After sufficient heat recovery the effluent is sent to the 2nd shift reactor for more hydrogen
33
6. HYDROGEN PURIFICATION :
In the Pressure Swing Adsorbtion Unit, the hydrogen is hydrogen leaving with a purity of more than 99.99 vol% and the rest of the process gas is purge gas and serves as primary fuel for the reformer. PSA technology is used to remove the impurities from the reformed gas. This is achieved by molecular sieves, which adsorb the contaminants at high pressure and allow the hydrogen to pass. To regenerate the molecular sieves the adsorber is depressurized. This releases the contaminants and after pressurization the adsorber is ready for reuse. The contaminants, which are released at low pressure, are collected in the purge gas drum and are used to meet part of the heat demand of the reformer. There are 12 vessels containing the adsorbent, out of which three are used for adsorbtion, others are used for desorption & maintaining the pressure. This is a automatic process each vessel having a cycle of 60 seconds.
34
Diesel Hydro Desulfurization Unit (DHDS):
DHDS (Diesel hydro desulphurization unit) is set up for the following purposes:
A step towards pollution control
To produce low sulphur diesel (0.25 w/w %) as per govt. directive w.e.f. Oct. 1999.
Feed consists of different proportion of straight run LGO, HGO, LVGO and TCO. Mainly two proportions are used:
74% SR LGO, 21% SR HGO, 5% SR LVGO
48% SR LGO, 24% SR HGO, 8% SR LVGO, 20% TCO
The DHDS unit treats different gas oils from various origins, straight run or cracked products. The feed is a mixture of products containing unsaturated components (diolefins, olefins), Aromatics, Sulfur compounds and Nitrogen compounds. Sulfur and nitrogen contents are dependent upon the crude.
The purpose of DHDS Unit is to hydro-treat a blend of straight run gas oil and cracked gas oil (TCO) for production of HSD of sulfur content less than 500 ppm wt.
The Hydrodesulphurization reaction releases H2S in gaseous hydrocarbon effluents. This H2S removal is achieved by means of a continuous absorption process using a 25% wt. DEA solution.
In addition to the desulphurization, the diolefins and olefins will be saturated and a denitrification will occur. Denitrification improves the product stability. The hydrogen is supplied from the hydrogen unit. Lean amine for absorption operation is available from Amine Regeneration Unit (ARU). Rich Amine containing absorbed H2S is sent to ARU for amine regeneration.
CATALYSTS
Catalysts used for this process are HR-945 and HR-348/448.The HR-945 is a mixture of nickel and molybdenum oxides on a special support. Nickel has been selected because it boosts the hydrogenating activity. The HR-348 and HR-448 are desulphurization catalysts; it consists of cobalt and molybdenum oxides dispersed on an active alumna. Its fine granulometry and large surface area allow a deep desulphurization rate.
Different catalysts based on Nickel and Molybdenum Oxide are used to enhance the rate of reactions.
Products Yields: Sl. No. Products wt% 1 Off-Gas 1.36 2 Wild-naptha 1.04 3 Diesel 97.1
35
Diesel Hydro-Treatment Unit (DHDT):
Objective : To meet the EURO-III/IV diesel quality requirement (<350/50 ppmS)
Feed : Straight run diesel / FCC diesel component/ Coker and Visbreaker diesel components. Catalyst : Ni-Mo oxides
Products Yields:
Sl. No. Products wt%
1 Off-Gas 2.65
2 wild-naphtha 2.8
3 Diesel 96.1
Wild naphtha feed from existing DHDS unit is processed along with DHDT wild naphtha in a stabilizer located inside DHDT battery limits for producing single naphtha product.
Processes in DHDT:
Refining & hydrogenation:
Removal of heteroatom (S, N2, O2) Saturation of olefins and dioelfins.
Hydrodesulfurization:
Hydrodesulfurization reactions are fast and take place in single step. Mercaptans: R-SH + H2 R-H + H2S
Sulfides: R-S-R + 2H2 2R-H + H2S
Hydrogenation:
Aromatic saturation & denitrification of heterocyclic compounds.
Hydrocracking:
Hydroisomerisation & then cracking into lighter isoparaffins.
Metal removal
36
TRAINING REPORT
@
37
Introduction:
Corrosion is a natural phenomenon which if left unattended can cause large economic losses. Many methods like paints, coatings of Zinc, Polymers and others are used for preventing corrosion. With pipelines becoming an integrated transportation mechanism for fluids as well as solids in some cases the protection of these pipes from corrosion is
important to increase their life.
This report deals with three important coating techniques and their laboratory quality inspection. Fusion Bonded Epoxy, Dual Fusion Bonded Epoxy, 3 LPE and 3LPP. The procedure of application of these coating involve similar steps. In FBE coating there is one layer of epoxy; in double FPE two layers; in 3LPE, one layer of epoxy, one layer of adhesive and one layer of Poly ethylene; in 3LPP, one layer of epoxy, one layer of adhesive and one layer of Poly propylene.
Fusion Bonded Epoxy:-
Fusion bonded epoxies are thermosetting epoxy coatings designed as a corrosion prevention coating for use on underground pipelines. These coatings are capable of operating in ranges from -100° up to 230°F depending on which grade is chosen, soil type, moisture content, thickness, temperature and other conditions. The values below are for a range of FBE types and specific product information should be obtained from the manufacturer’s technical data sheet.
History
Fusion bonded epoxy (FBE) has been one of the premier coatings of choice on pipelines for many years due to its durability, corrosion protection properties and ease of application. Starting in the mid 1970’s FBE was used on the girth weld area as a field joint coating and since that time millions of girth welds have been coated utilizing this product. In the mid 1980’s FBE’s were utilized to coat induction bends, flanges, valves, tee’s and other fittings used in a pipeline system allowing the owner companies to have a high quality corrosion protection coating from start to destination of their pipelines. Technological advances in the application techniques allow for a low cost, high production process for battling corrosion on the weld areas of pipelines.
Definition
Fusion bonded epoxies are a one part, heat curable, thermosetting epoxy utilized for corrosion protection. FBE’s are applied to heated parts in a powder form that rapidly gels from liquid to a solid and have remarkable adhesion to the steel surface. FBE’s are also are very resilient coatings that resist damage during handling. FBE’s are environmentally friendly containing no volatile organic compounds (VOC’s). Societies for Protective Coatings (SSPC), NACE International (NACE), and the International Standards Organization (ISO) have developed standards for surface preparation and application of FBE
Storage Temperature of Raw Epoxy : Below 27 C
For sea submerged pipes Concrete Coating is done on the top of the Epoxy Coating to counter the buoyancy, so rough outer finishing of the epoxy coating required to grip the concrete to prevent the slippage of the concrete during installation of the pipes.
38
Dual Fusion Bonded Epoxy:-
All conditions similar to FB Epoxy coating but two layers of FB Epoxy is applied to provide extra mechanical strength.
Three Layered Poly Ethylene:-
1 – Steel Pipe
2 – Epoxy Layer (0.2 mm) 3 – Adhesive (0.2 mm)
4 – Poly Ethylene/ Poly Propylene Layer (2-5 mm)
1 – Steel Pipe
The steel pipes are charged and the temperature of the pipe is increased. The coating is applied using electrostatic spray and due to positively charged surface and negatively charged particles the epoxy gets applied and due to the temperature the polymerization occurs and the coat is formed. After the application of the coat the pipe is kept for curing for some time.
Curing of the coating after the application may be equally important as the application itself depending on the use. Curing means allowing for the solvent to evaporate and leave back the coating particles to coalesce and for a solid coating
2 1 3 4
39
2 – Epoxy Layer
Above is the structure of the epoxy, the epoxy layer is hard and provides for excellent corrosion resistance. The epoxy application may in done in two ways, electrostatic spraying of powdered epoxy or application of liquid epoxy. I case of liquid epoxy the epoxy and the catalyst are mixed at the application site and the reaction occurs on spot to form the coating. Generally liquid epoxy is used in coating of internal surface as it is easier to apply using spray technology. But it is also used in external coating depending on the specifications from the client. . The suppliers of the powder epoxy are 3M, Vulspar, DuPont, BASF. The suppliers of the liquid Epoxy are 3M, Henspel, Exonovel.
3 – Adhesive
The adhesive layer is used to create the necessary bond between the epoxy and the Poly ethylene/ Poly propylene layer. The adhesive has two end one polar and other non-polar. The Polyethylene has polar ends and the epoxy non polar ends. To bond these two layers the adhesive is required. The suppliers of the adhesive are DuPont, Borogue, Hyndai
4 – Poly Ethylene
The poly ethylene layer or the poly propylene layer is added to increase the mechanical strength of the coating. Polyethylene is generally black in color due to presence of carbon black in it whereas polypropylene is white due to presence of Titanium oxide in it. . The suppliers of the Poly Ethylene are Bassel, Borogue, Hyndai
APPLICATION PROCESS (3 LPE Coating )
A. INLET INSPECTION
The pipe is visually inspected for any transit defects and other manufacturing errors. It is also checked for oil and grease which may have got applied on the surface during transit.
B. ENVIRONMENTAL CONDITION MONITIRING
The environmental conditions are very important for preparation of the surface for coating. The surface must be moisture free.
S.No. Pipe Temperature Ambience
Temperature Relative Humidity Dew Point
1 28 C 27 C 70 % 23 C
2 27 C 28 C >85 % 27 C
In case of 1 the pipe temperature is greater than the Dew point so the condensation of the moisture on the
pipe surface is negligible.
But if the moisture content is high in the environment generally above 85% the Dew point increases as in case 2. In this case the moisture condenses on the pipe surface creating problems during coating application.
Thus to remove this moisture the pipe is generally heated to 65 C – 85 C depending on the requirement of the client.
40 C. FIRST STAGE BLASTING
The surface of the pipes generally have the deposits of rust, mill scales. The major part of the surface preparation includes blasting the surface of the pipes with the shots and grits of steel as shown in the figure. The surface if blasted creates roughness and increases the surface area available for bonding. The Anchor like structure created on the surface helps in holding the coating as shown.
The steel shots have the radius of 0.85 mm and when due to the abrasion the radius falls below 0.3 mm the shots are discarded. The angular steel shots are used for creating roughness using the peen action. Initially 70% Grits and 30% shots are mixed but with time the grits get converted to spherical structures and thus in later stages only the angular grits are added to compensate the depletion of shots
42 The action of steel grits
43
Steel Shot : By contrast, the action of the steel shot is one of impact alone. Results are similar to striking
the surface with ball peen hammer. Shot will peen and hammer the surface, which is an advantage when heavy brittle deposits (i.e. mill scale ) must be removed from the surface. The energy of the heavy metal hitting the surface effectively cracks and pops the heavy brittle rust and mill scale from the surface. It is not, however as efficient in removing surface residues since these may be pounded into the surface by the peening action. The peening action on the metal both compresses the surface and stretches the meta, so that care must be taken in shot blasting the sheet metal. The stretching of the metal surface can cause excessive deformation and warpage.
Shot blasting is usually more effective on heavier steel plate and shapes as they can absorb the impact of the shot and the surface compression without excessive warpage.
Steel Grits : In blasting action because of the sharp edges it creates a cutting action. The sharp edges cut
into steel forming sharp peaks and valleys which increases the adhesion potential. D. PHOSPHORIC ACID WASH/ HIGH PRESSURE WATER WASH
The usual cold phosphate pretreatment is combination of phosphoric acid to water soluble solvent such as butyl alcohol. Treatment with phosphoric acid can inhibit the rusting of the surface for a considerable period of time. The phosphate wash is followed by high pressure water wash. This is used to remove the chlorides, sulphides and dust on the surface which could cause problems in the coating.
Properties of the Phosphoric Acid Wash
H3PO4 + Organic Surfactant -> 80% Other additives -> 20% The above mixture is diluted 10 ± 1% v/v The pH of the solution is around 1-2
The volumetric flow rate of the Phosphoric wash is 1 L/min Manufacturer- Chemital Rai (Germany )
Properties of the Water Wash
De ionized water is used. Pressure > 1000 psi Flow Rate = 19 L/min pH = 6-8
E. SURFACE INSPECTION
The surface of the pipe is checked for Slivers1, Lamination and other defects.
F. SECOND STAGE BLASTING:
Pre Heating at 60-85 C and then blasting operation as described in section C
1“Slivers are elongated pieces of metal attached to the base metal at one end only. They normally have
been hot worked into the surface and are common to low strength grades which are easily torn, especially grades with high sulfur, lead and copper.”- AISI Technical Committee on Rod and Bar Mills, Detection,
44 G. QUALITY INSPECTION AFTER BLASTING
a. Degree of cleanliness on the basis of the ISO 8501-1 standards
b. Roughness Profile2 : Generally the specification of the roughness is about 40-100 Micrometer. The
observed value during field visit was 54.66 micrometer.
c. Salt Contamination Level : Maximum Specified Value 2 microgram/cm2. The observed value during field visit was 0.4 microgram. 1.6 ml of distilled water is absorbed in a filter paper and is then placed on the pipe for some time, it absorbs the salt on the pipe surface and then it is kept in the instrument which works on the principle of conductivity and the salt concentration is determined. d. Residual Dust Level – ISO 8502-3
The procedure include application of a special adhesive tape to the surface and on removal the dust particles get stuck to the surface of the tape and on comparison with the standard the level of contamination is determined and if above level 2 the surface is unacceptable. There are a maximum of 5 levels
H. CHROMATE APPLICATION
A thin layer of Cr2(SO4)3 is applied on the surface to make the surface more adhesive to the epoxy which will be applied in subsequent stages. The application of the chromate layer improvises the adhesive properties of the surface but if the Thickness of the layer > 2 micrometer then a brittle layer over the pipe undermines the surface properties.
The inspection for proper application of the chromate layer involves visual inspection of the layer. The colour must be between light yellow and light brown.
Manufacturer- Chemital Rai (Germany )
1. 2Rz: Rz is the arithmetic mean value of the single roughness depths of consecutive sampling lengths. Z is the sum of the height of the highest peaks and the lowest valley depth within a sampling length.
45 I. INDUCTION HEATING :
Induction Heaters provide alternating current to an electric coil. The electric coil induces the current in the pipe and due to resistance and hysteresis losses the pipe gets heated.
The pipe is heated to
S.No. Type of Coating Temperature Range
1 3 LPE 180-220 C
2 3LPP 200 – 230 C