Internship Report(30th June, 2014 -- 28th July, 2014)

Submitted By:

Mr. Suneel Parwani Industrial Electronics Engineering

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INTERNEE PROFILE

Name : Suneel Parwani

Father Name : Jai Pirkash

Institute : IIEE, NED University Karachi.

Department : Industrial Electronics Engineering (6th Semester)

E-mail : suneel.parwani@iiee.edu.pk

Contact : +9-333-3480927

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ACKNOWLEDGEMENT & PREFACE

I am very thankful to Almighty who gives me the potential and helps me in the smooth and peaceful completion of my internship.

This report is about four week summer internship program, which I have completed at BYCO Petroleum Pakistan Limited from 30th June to 28th July’14. I would like to thank my helpful supervisors, Mr. Qazi Bilal Zuberi, Mr. Sarang Ismail & Mr. Shahid Yousuf for their immense service and support and utmost patience in throughout the entire period of my training. The supervision and support given by them truly help me in the progression and smoothness of the internship program. The co-operation is much indeed appreciated. Last but not least I would like to thank all the managers, engineers and workers who guided me and shared their knowledge and experiences.

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TABLE OF CONTENTS.

No.Topic Page No.

1 About Byco 3

2 Single Point Mooring (SPM) Technology 4

3 Environment, Health & Safety 6-10

4 Lab 11-12

5 Operations 13-18

6 Inspections 19

7 Mechanical 20

8 Electrical 21

9 Instrumentation 22-30

10 Oil Movement 31-32

11 Conclusion 33

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ABOUT BYCO PAKISTAN LIMITEDByco is Pakistan’s emerging energy companies engaged in the businesses of oil refining, petroleum marketing, chemicals manufacturing and petroleum logistics. Headquartered in Karachi, we are serving our mission to fulfil the energy demand within and beyond borders.

Companies under Byco umbrella are:

Byco Oil Pakistan Limited (BOPL) Oil Refining & Chemical Manufacturing

Byco Petroleum Pakistan Limited (BPPL) Oil Refining & Petroleum Marketing

Byco Terminals Pakistan Limited (BTPL) Petroleum Infrastructure & Logistics

They are engaged in manufacturing of a wide range of petroleum products such as Liquefied Petroleum Gas, Light Naphtha, Heavy Naphtha, Kerosene, Jet Fuels, High Speed Diesel and Furnace Oil for bunkers and energy generation with the objective to achieve sustainable productivity, profitability and high standards to address the environment, health and safety requirements.

Oil refining complex-I is located 50km from Karachi towards Hub in Balochistan Coastal area. The location of an Oil Refinery has an important impact on its refining margin, since it determines how well it can access feed stocks and distribute its products. The Location also dictates whether feed stocks and product can be transported by sea via pipe lines or road. Coastal area located Refinery like Byco typically has a competitive advantage over those located inland due to lower logistics costs and having total refining capacity to 35,000 (barrels per day). The Company also have settled another Oil refining complex-II with the capacity of 120,000 barrels per day which.

They take pride in having the largest capacity crude oil storage tanks in the country. Their petroleum distribution network supports movement of petroleum products and provides greater economies of scale. Their marketing network supports retail outlets in more than 80 cities all over Pakistan and is an emerging leader in oil marketing sector of our economy.

Their diverse and highly skilled workforce consists of approximately 800 dedicated employees shared among Byco companies.

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SINGLE POINT MOORING (SPM) Technology

The Single Point Mooring (SPM) facility being set up for the first time in Pakistan will revolutionize the handling of petroleum and oil products in the Country. The facility is being setup to allow the handling of imported crude oil and other petroleum products through the SPM – an open sea anchorage with sub-sea and sub soil pipelines connecting it to the on-shore facilities.

This facility is being set up in the deep sea, at a distance of approximately of 15 km from the Byco site located at Mouza Kund, Balochistan, Pakistan. The floating jetty will be connected to crude oil tank farm of approximately 130,000 metric tons, via 3.3 km on-shore pipelines and 11.5 km off-shore 28" pipelines.

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EHS (ENVIRONMENT, HEALTH AND SAFETY)

Introduction:Environment, Health and Safety is the topmost component of Byco’s business core values and commitment. Refining industries employ large and complex refining units, processing highly flammable oil materials at high temperature and pressure. EHS aim to add value and create an improved environment for the customers by enhancing their relationships with the product, employees and environment.

EHS

Environment Health Safety

The International standards that are being followed at the Byco are: EMS (Environmental Management System) ISO 14,001 QMS (Quality Management System) ISO 9001 OHSAS (Occupational Health Safety Assessment Series) ISO 18,001

Emergency Response Time Department (ERT):ERT department ensures all systems are in place that is required to mitigate and control any undesirable and hazardous situation (causing threat to Environment, health & Safety) arising in case of any failure or accident.ERT Plan is based on the following fundamental principles:

1. Minimizing environmental impact 2. Minimizing harm to people 3. Minimizing damage to the machinery4. Protecting the reputation of Refinery

Emergency Declaration:The emergency is declared by the siren of alarm with 3 seconds up and down tone. At that time the workers are ordered to go to Assembly points (people gathered here). There are 6 assembly points located at different location that are safe.

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And when the condition is controlled, there is another alarm siren with continuous tone to indicate that emergency is over and the conditions are under control and safe.There are sensors, manual call points as well as emergency call number (1191) available so that the emergency situation is controlled as fast as possible.

Hazards : 1. Fire 2. Bomb Threat 3. Leakage/spill (oil and chemicals) 4. Natural disasters 5. Non biodegradable waste6. Emission of toxic gases (SOX, NOX, CO₂, CO etc)

Safety Measures:1. The tanks are covered with pipelines with showering valve having water and foam in

them.2. There are portable foam trolleys available at different areas of the plant area.3. There are work permits allotted depending on the work requirements.4. All the electrical and electronics devices are grounded properly.5. There is a panel which look after the emergency call system6. Proper medication and first aid is available7. There are emergency response vehicles which are always ready to tackle the emergency

conditions.ERT measurement & monitoring plan is to check & improve the systems in place, which includes:-

1. Eliminate2. Substitute3. Engineering Control4. Administrative Control

FIRE FIGHTING MECHANISM

There are four main classes of fire:1. Class A (solid/combustible fire such as fires with wood or trash)2. Class B (liquid/flammable fire)3. Class C (electric fire)4. Class D (metal fire)

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Firefighting is the act of extinguishing fires. Firefighting is a highly technical skill that requires that professionals have years of training and education to become proficient. In Byco, there is a panel of 4 people for this fighting.

Fire Fighting Material:1. DCP (dry chemical powder) for combustible fire2. Carbon dioxide for electrical fire 3. Foam (fluoroprotein i.e. 3% foam and 97% water) 4. Water

Safety Equipments PPE’S (personal protection equipments):1. Hard helmets2. Safety shoes3. Cover all (dungaree for males and females)4. Gloves5. Mask6. Goggles

Fire Fighting Equipments:Equipments which helps in alerting from emergency situations:1. Emergency response vehicles (2)2. Fire extinguishers3. Fire pumps4. Foaming system 5. Smoke detectors6. Fire Alarms7. Smoke Detectors 8. PCV (Pressure Control Valves) 9. TCV (Temperature Controlling Valves)10. LCV (level Control Valves)

EMERGENCY RESPONSE VEHICLES:There are 3 vehicles termed as ERV

1. Emergency response vehicle – I2. Emergency response vehicle – II3. Ambulance

Emergency response vehicle – I:

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It is old modeled fire tank. It contains Foam, water and DCU. The capacity of water is 2000 liters, foam is 5000 liters and DCU is 1000 Kg. For DCU, there are 4 Nitrogen filled cylinders and required pressure is 14 bars. Emergency response vehicle – II:It is advance model of Fire Tender, can be used easily. It contains water and foam. The capacities are 3000 liters water and 4000 liters foam.

M EDI CAL CLINIC

Medical center is one of the most important departments working under the umbrella of EHS department. In Byco the medical center has all the basic and necessary facilities available 24/7.

Facilities:The medical center has following facilities:

1. An Ambulance2 . Consultation room3. Proper storage for medicines4. 10 first aid boxes5 . Well trained nursing staff

Activities of Medical Center:The medical center is engaged in the following routine activities:

1. OPD2 . Record of employees to maintain health assessment3 . First aid treatment4 . Noise level test5 . Eye sight test6. Vaccine record

Normally the cut and burn injuries are reported in the medical center.

Types of Burn:

1. 1st Degree burn: Redness on the skin and it feels burn.

2. 2nd Degree burn: Redness on the skin and blusters appears on the skin, in this burn epidermis & endodermis layers are damaged.

3. 3rd Degree burn: In this type the endodermis layer and nerves got damaged.

4. 4th degree burn: In this type the bones got damaged and the person has very little chances of survival.

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Safety Precautions:

i). Permit to work system:There are four types of work permits in the industry

I. Hot Work PermitAll works in which temperature is involved, naked fire is used or flame is generated requires hot work permit

II. Cold Work PermitWorks which don’t require naked flame or temperature change is observed will be done through cold work permits.

III. Confined Space CertificateAll work which is done in close area where lighting and air passage is not available is under this category.

IV. Excavation CertificateThe refinery is grounded with pipelines and wires so the area should be properly tested out before digging for any work then this certificate will be issued.

ii). Fire Drill: Fire drills are held every Tuesday at 11 AM to train the employees about the fire fighting techniques and to keep the firemen in practice.

iii). Restrictions:The principle hazards at refineries are fire and explosion. The use of matches, lighters, cigarettes and other Smokey material is generally banned in the plant except in specially designated areas.

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LABLaboratory is basically the eye of the refinery where quality is controlled of our products .It is the place where our samples are checked. It is checked whether Byco products are meeting the specifications suggested by A.S.T.M.

TESTS CONDUCTED IN LABORATORYThe following tests are conducted on the products.

Test Instruments Products1. Pour point2. Cloud point

Ice Bath

3. Existent gum content check Existent Gum check meter MS4. Flash point By Able Kero

By PMCC HSG and FFO

6. Oxygen Stability Oxygen Stability meter MS JFTOT Jet Fuel

8. Water content check Dean Strack meter9. Viscosity Viscosity Bath with two solvents

Acetone Jet Fuel Water Crude, Diesel

and FFO11. ASTM colour check

Coloured liquids Transparent Liquids

Chromo meter naphtha

12. Absorbance check Spectrophotometer13. Conductivity Conductivity Meter

14. Sulphur Sulphur Check meter Sweet Naphtha

15. Distillation Distillation Unit Naphtha, MS, Diesel

16. Fuming Hood

17. Octane number check ZeltexRON

18. Oxygen content Portable O2 analyzer

19. Moisture Content Moisture Analyzer

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SIGNIFICANCE OF ABOVE TESTS:-

FLASH POINT:The Flashpoint temperature is one measure of tendency of the test specimen to form a flammable mixture with air under controlled laboratory condition. Flash point is used in shipping and safety regulations to define flammable and combustible material.

POUR POINT:The pour point of a petroleum specimen is an index of lowest temperature of its utility for certain applications. It tells the lowest temperature of the product at which can be poured easily.

VISCOSITY:Many petroleum products, and some non petroleum products, are used as lubricants ,and the correct operations of the equipment depends upon the appropriate viscosity of the liquid being used. In addition, the viscosity of many petroleum fuels is important for the estimation of optimum storage, handling, and operational condition. Thus, the accurate determination of viscosity is essential to many product specifications.

DISTILLATION:The distillation characteristics of hydrocarbon have an important effect on their safety performance, especially in case of fuels and solvents. The distillation characteristics are critically important for both automotive fuels and aviation gasoline, affect starting , warm up, and tendency to vapor lock at high operating temperature or at high altitude ,or both. The presence of high boiling point components in these other fuels can significantly affect the degree of formation of solid combustion deposit.

OCTANE NUMBER TESTThis test is basically run in CFR ENGINE room. This test checks the anti knocking characteristic of the fuel. It is compared with the standard mixture of n-heptane and iso-octane.

COPPER STRIP CORROSION:This method covers the detection of the corrosiveness of gasoline, naphtha, kerosene, aviation turbine fuels having Reid vapor pressure no greater than 18 lb.

KINEMATIC VISCOSITY:This method covers the determination of kinematic viscosity of liquefied petroleum products, both transparent and opaque. This method is intended for application to liquid For which the shear stress & shear rate are proportional

ASTM COLOR:This method describes a procedure for visual determination of the color of wide variety of petroleum products such as lubricating oil, heating oil, diesel fuel oil and petroleum waxes.

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OPERATIONSIn Byco, Crude is pumped to storage tanks and then passes from different process to meet the demands of customers then release and supply to the customers through bowser tanks.There are three portion of plant area,

1. Process2. Storage3. Supply

The process is divided into 4 units1. CDU (Crude Distillation Unit)2. LSU ( LPG Separation Unit)3. HDT (Hydro Reformer Unit)4. Merox

The refining process initiates from the crude tanks and follow the sequence of different process given below:

Booster Pumps Feed Pump Heat Exchangers

Desalters Heat Exchangers Pre-Flash

Furnace Distillation Column Respective

Operations

1. CRUDE DISTILLATION UNIT

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Crude of the storage tanks are prepared by boosting with the help of booster pumps then supplied to the feed pumps which send the crude to pre-heater then to Desalter at 105psi pressure in CDU.

DESALTER:A desalter is a process unit on an oil refinery that removes salt from the crude oil. The salt is dissolved in the water in the crude oil, not in the crude oil itself.Conventionally, an AC (Alternating Current) electrostatic dehydration system is used to remove high salinity formation water from the crude oil stream. This process relies on establishing a high voltage AC electrical field in the oil phase of dehydrator/desalter vessels. The electrical field imposes an electrical charge on water droplets entrained in the oil stream, thus causing them to oscillate as they pass through the electrodes.During this oscillation, the droplets are stretched or elongated and then contracted during reversal of the imposing AC electrical field. During this agitation the water droplets co-mingle and coalesce into droplets of sufficient size to migrate, by gravity, back into the lower water phase of the vessel for disposal thus water is collected at the bottom while crude is at the top.In BYCO, there is a Chemical (demulsify), use to separate water from the crude in desalter unit.

PREFLASH TOWER:The crude then sends to pre-flash tower having 20 trays, here the crude and steam are comes in contact and counter current is generated. The pressure of crude is 105 psi. This setup is done to remove naphtha from the crude, i.e. naphtha being a lighter parts separates and collected at the top of the tower while remaining crude is assembled at the bottom.NOTE: Naphtha is removed because it increases temperature and pressure up to great extent. Thus increment of feed is difficult but if naphtha is removed then feed can be increased.

PRODUCT OF PRE-FLASH TOWER:The naphtha obtained from the tower is called total naphtha. Then total naphtha is passed through fin fan coolers where steam is condensed and then obtained in the pre-face accumulator where water is drained out and waterless total naphtha is obtained and propel to splitter.

The crude obtained from the pre-flush tower is sent for pre-heat, where it is passed through heat exchangers.

HEAT EXCHANGER:The heat exchangers used at ORC-1 are mostly Shell & Tube type with different specifications. They are used at different processes for the same purpose, exchanging heat between two fluids. The code that all heat exchangers follow is ASME VIII Division 1. There are an old and a new train, each has two pipes, one carry crude while other carry product, and these trains are used as heat exchanger.Crude is present in the tube while product runs in the shell side and vice verse. The heat of product is exchange with the crude’s cold temperature.

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Some of these exchangers are as follows.1. Resid HSD Heat Exchanger2. HSD Crude Heat Exchanger3. Resid Crude Heat Exchanger4. Crude HSD Heat Exchanger5. Crude Kero Heat Exchanger6. Crude Resid Heat Exchanger7. Hot Oil Heat Exchanger8. Kero Cooling water Heat Exchanger9. Cooling water Heat Exchanger

After passing through exchangers the crude is transferred to the furnace having 12 burners and then Born Heater having 10 burners.

BORN HEATER:It is a type of furnace working on the principle of Burner management system.There are two sections in it.

1. Radiation 2. Convection

The dual type of burner is present in it. Its temperature is maintained at 220 ̊C.

Crude flows in the convention section in the coil of pipes. It is a dual burner in which two types of fuels are used. The inlet temperature to the burner is 220oC and outlet temperature is 350oC. There are four pipes entering in burner, Steam, Oil, Pilot and Gas. Where oil and gas are used as fuel, pilot is used for ignition and steam is used as atomizer.

DISSTILATION UNIT:The remaining crude then comes to distillation tower, there are levels and different products are achieved. The separation is distillation tower is due to the boiling point range. There are 38 trays in the tower where the oil the different boiling point is collected and that is carried in sump and then accumulated in the side striper.

STRIPPING SECTION:The product obtained from the distillation tower is collected in the stripping section; here some chemical properties are tested and then refined (if required) according to the requirement.Stripping section is involved because the product quantity is not defined. In side stripers, kerosene and HSD are contained where naphtha in these products are separated and carried to splitter. At the bottom, Fuel Oil is obtained in which viscosity is altered and then stored in vessels to use in furnace and also used as hot oil. Hot oil is pumped to the furnace and then to the heat exchanger where it heats the other fluid and then return to the hot oil tanks.

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REFLUX:Reflux material (naphtha contained in accumulator) is used in side striper for temperature control of the kerosene to settle down at bottom and let naphtha to evaporate to top to get collected.

NAHTHA TREATMENT:The naphtha collected in pre-flush unit and side stripers are now carried to the splitter where it is heated then due to temperature difference, in tower at height where temperature is at 112oC, light naphtha is obtained which is 14% to 16% and at the bottom of the tower where the temperature is 170oC, heavy naphtha is present. Then heavy naphtha is carried to re-boiler and again recycled in splitter tower and at the end it is carried to the Hydro-treater Unit and light naphtha is carried to LPG Separation Unit (LSU).

2. LPG SEPARATION UNIT (LSU):

In LSU, light naphtha is the feed obtained from top of the splitter tower. Then it is carried to Depropanizer, from where propane is separated and then taken to the Debutanizer in which Butane is separated in same manner. Since LPG is composed of 40% Butane and 60% Propane as per requirement then it is transferred to the LPG bullets after sweetening in Merox.

3. HYDRO-REFORMER UNIT:

In hydro-treater unit, the feed is heavy naphtha with hydrogen gas which is pre-heated with the help of heat exchanger from the shell side up to 210oC and then heated in the furnace in order to attain the temperature of 300oC which is compulsory for the reaction in the reactor. To cool the product, it is passed through fin fan cooler and then trim cooler.Then it is accumulated in the Product Separator. Where water is escaped from bottom, naphtha is obtained from middle where the pressure of 5 bars is maintained through pressure control valve (PCV).

TRIM COOLERA trim cooler is a type of auxiliary cooler that makes up a part of a process plant's cooling system. Trim coolers are typically designed to work only part of the time (e.g. during the hottest weather) and for only part of a complex cooling system.The naphtha obtained from the Hydro-treater unit is then carried to the Desulphurizer tower.

DESULPHURIZER TOWER: Naphtha is again preheated through heat exchanger and then to the tower. The level of the naphtha is maintained up to 65% by Level Control Valve (LCV). Then it is reacted with hydrogen gas from which sulfur reacts with H2 and form sulfur products which are then removed. This process is repeated by reheating the naphtha from waste heat exchanger and then convention zone of furnace till the sulfur content becomes less than 0.5 ppm in the product. Then remaining

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naphtha is free of sulfur that is sweet naphtha at temperature of 230oC which acts as a feed for Reformer Unit. REFORMER UNIT:The reformer feed is carried to the heat exchanger for pre-heat. In reformer unit, there are 3 reactors in which different types or reactions are performed. For these reactions, a temperature of 490oC is required. For this, a furnace is provided prior to every reactor. The first furnace is largest in size of these three and the third one is smallest because reaction in the first reactor is endothermic and in the last reactor, exothermic reaction occurs. After completing the reactions, the naphtha returns to the heat exchangers and then to product separator.

PRODUCT SEPARATOR: In product separator, from top H2 is obtained from where some part of gas is recycling compressor and some part is taken to booster compressor. From bottom, gasoline is obtained. Gasoline is then sent to stabilizer to control Reid Vapour Pressure (RVP). Then it is run down to storage.

4. MEROX:

Propane and light naphtha is carried to the Merox Unit. Here sweetening of propane and light naphtha takes place. This is done by reacting Propane and light naphtha with the caustic soda. Through which sweetening is done and light naphtha is converted to Gasoline and butane is sent to run down.

The difference in gasoline obtained from Merox and Reformer Unit is the Octane number. The octane number of gasoline obtained from Reformer Unit is 92. Whereas,the Merox’s gasoline has octane number of 65.

The process flow diagram is attached here

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Proces s Flo w Dia gra m

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INSPECTIONThe codes and standard followed by Byco are ASME, API, and ASTM.There are two areas of inspection

1. Stationary area The mechanical integrity is ensured here.

2. Rotatory areaIn this area, vibrational motion is monitored.

MECHANICAL INTEGRITY:The mechanical structure is observed and checked. The damages due to welding, temperature increment is very dangerous for the refinery. Following things are monitored

1. Flame pattern2. Refractory material3. Tube’s hanger expansion and carbonization 4. Transfer line temperature 5. Corrosion 6. Welding damages

VIBRARTION CHECK:The displacement is observed in this test, the radial and axial vibration is checked in mm/s

INSPECTION SCHEDULE:There are plans and schedules of the inspection department. The furnace is observed weekly, locating pins are affected by thermal expansion. The heat exchanger is examined properly.

INSPECTION TOOLS:The following tools are used for inspection purpose.

1. ALCOMETER:It is use to check thickness of paint in micsrometer. The tanks of LPG unit are critical so thickness of paint is sustained and properly check through AlcoMeter.

2. TEMPERATURE METER:Ultraviolet light is used to check the temperature of the insulation.

3. SONA GAUGE:The thickness of the material is checked, the material is greased first to get right and true reading. In Byco, the thickness of flange is checked using sonagauge.

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MECHANICALThe mechanical department is mainly responsible for the overall maintenance of the plant and the modification of existent utilities and installation of new equipments. To manage the work efficiently the mechanical department is further divided into two sections i.e.

Mechanical

Stationary Rotary

The mechanical department in ORC-I is responsible for the maintenance of all the following equipments and their parts like:

1. Heat Exchangers2. Pumps3. Compressors4. Boilers5. Turbines6. Furnaces7. Valves8. Piping9. Cooling Towers

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ELECTRICAL Byco has its own power generation through diesel generators. Its load is divided into two categories.

1. Plant load2. Lighting Load

For plant load, there are 3 generators of 1.5MW with 60Hz frequency. . Plant load generators are rental generators from allied engineering. These generators are maker of Caterpillar. They work on 60Hz frequency and provide 460 volts for three phase and 230 volts for one phase. The continuous load of the plant is 1.7MW; critical load is 2MW whereas during shut down, the load of reformer and boiler is 650 KVA.

Synchronization system is used in which all the generators are synchronized so that all the generators bear equal loads and then transferred in the plant.

In Byco, one generator provides fixed power and two generators are on sharing. So that if any changes occur then sharing generators will adjust according to it. The power factor should be limited to 0.9. For controlling system of Caterpillar generators, RA Panel and PLC devices are used.

PLC system is mounted in generator and RA panel is kept in control room from where all the parameters are shown as well as all the changes are also recorded in it. From this panel automatic synchronization can also be done. It is the most secured system provides 100% safety for generator engines.

A device is also there named with Service Meter Unit (SMU) which indicated the service hour or generators. From which the service and maintenance schedule is followed. These generators may be shut down at extreme limits that are; min 23 Amp and at max 40 Amp.

For lighting load, there are two generators of 550KVA and 365KVA are used which includes lightning and office load which is fulfilled by two own generators. One is made of Cummins has the capacity of 550KVA and other is made of Perkins having the capacity of 365KVA operating at 50Hz. For starting these generators, a charge breaker is used which is pumped 5 times. When the breaker gets harder and its motor of synchronization gets started, then it is ready to get started.

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INSTRUMENTATIONInstrumentation is defined as the art and science of measurement and control of process variables within a production or manufacturing area. In Byco, the process are automated and controlled through Distributed Control System.

HUMAN INTERFACE STATION:There is a station where all equipments for controlling the plant is present, the process is observed on the monitors working according to the defined processing. The annunciator is also located here. All the wirings from Junction Box (JB) come to the cabinet located in the station and interfaced with Field Control Station, then connected to DCS systems.

DISTRIBUTED CONTROL SYSTEM

A distributed control system (DCS) refers to a control system usually of a manufacturing system, process or any kind of dynamic system, in which the controller elements are not central in location (like the brain) but are distributed throughout the system with each component sub-system controlled by one or more controllers.

DCS (Distributed Control System) is a computerized control system used to control the production line in the industry. The entire system of controllers is connected by networks for communication and monitoring.

DCS is a very broad term used in a variety of industries, to monitor and control distributed equipment.

Electrical power grids and electrical generation plants Environmental control systems Water management systems Oil refining plants Chemical plants Sensor networks etc.

In Byco, the DCS of Yokogawa Cooperation of America is implemented.

CONTROLLING OF PROSESS VARIABLES

PressurePressure is probably one of the most commonly measured variables in the plant. It includes the measurement of steam pressure; feed water pressure, condenser pressure, crude oil pressure and many more.

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Pressure is actually the measurement of force acting on area of surface. We could represent this as: Pressure =Force /Area Or P= F/ AThe units of measurement are either in pounds per square inch (PSI) in British units or Pascal (Pa) in metric. As one PSI is approximately 7000 Pa, we often use kPa and MPa as units of pressureThe measure of pressure is, therefore, relative and pressure measurements are stated as either gauge or absolute.

Measuring techniquesThe method employed here to measure the pressure in Byco is discussed below.

PRESSURE GAUGES

Bourdon Pressure Gauges

PRINCIPLE: The Bourdon pressure gauge uses the principle that a flattened tube tends to change to a more circular cross-section when pressurized. Although this change in cross-section may be hardly noticeable, and thus involving moderate stresses within the elastic range of easily workable materials, the strain of the material of the tube is magnified by forming the tube into a C shape or even a helix, such that the entire tube tends to straighten out or uncoil, elastically, as it is pressurized.

Here Byco has C shaped bourdon tubes.

Bourdon tubes measure gauge pressure, relative to ambient atmospheric pressure, as opposed to absolute pressure; vacuum is sensed as a reverse motion.

Diaphragm Gauges

Diaphragm consist of a tough and neoprene membrane connected to a metal spring. There is hollow space present between the membrane One side of diaphragm is exposed to pressure being measured, while the other side to some other area having different pressure.

PRESSURE TRANSMITTER

The transmitter consists of transducer and transmitter. The pressure is sensed and converted in electrical quantity and then transmitted to the control section. Range of differential pressure is 0-20m bar.

The transmitter installed varies with the liquid flowing. There are following positions to attach pressure transmitter to obtain pressure readings

PT via Impulse line (pressure of clear liquid) PT via diaphragm (pressure of liquid with suspended particles) PT via impulse line on LO-SIDE Plugged (pressure of Slurry).

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Level

Level is actually the height of liquid contained in the vessel.

Measuring TechniquesThere are two types of level detection

1. Continuous level detection2. Single point level detection3.

The measurement techniques are follows:

Dipley MethodThis technique includes a simple method i.e. to dip a rod in the container, the wet portion tells the height of liquid.

RADAR MethodThe ultrasonic rays are transmitted on the surface of the liquid, reflection phenomenon tells the level of the liquid.

Differential Pressure MethodThe method includes comparison of pressure at two different levels.

When the container is openThe pressure at dead level is compared with the atmosphere pressure so every predetermined pressure reading indicates the level of the container.

When container is closedThe pressure of dead level is compared with the pressure at the upper portion of the container. Thus level is determined.

Capillary tube MethodA sensor that changes internal pressure when temperature change. Capillary tube sensors use temperature sensitive liquid.In Byco, the tube is filled with viscous liquid and works on Differential Pressure system.

All above methods are employed at BBPL.

TemperatureThe degree of hotness and coldness is termed as temperature. Or it is a measure of the thermal energy per particle of matter or radiation.

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Measuring Techniques

Temperature via ThermocoupleThe principle here is the voltage generated by the thermocouple is proportional to the temperature difference between the point where temperature is measured and the point where thermocouple I connected to the device.PropertiesMillivolt range I availableVery low temperature to voltage sensitivity

Temperature via RTDThe principle is the passing current through RTD generates a voltage across the RTD , by measuring this voltage , resistance is determined thus temperature is determined. The 0C indicated the resistance of 100 ohm and measuring up to 850C.

Types of RTD

2-Wire RTD2-wire construction is the least accurate of the 3 types since there is no way of eliminating the lead wire resistance from the sensor measurement. 2-wire RTD’s are mostly used with short lead wires or where close accuracy is not required. Measured resistance isRt = R1 + R2 + Rb

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3-Wire RTD3-wire construction is most commonly used in industrial applications where the third wire provides a method for removing the average lead wire resistance from the sensor measurement. When long distances exist between the sensor and measurement/control instrument, significant savings can be made in using a three wire cable instead of a four-wire cable. (R 1+2+R b ) - (R 2+3) = (R b ) The 3 wire circuit works by measuring the resistance between #1 & #2 (R 1+2) and subtracting the resistance between #2 & #3 (R 2+3) which leaves just the resistance of the RTD bulb (R b). This method assumes that wires 1,2 & 3 are all the same resistance.

4-Wire RTD 4-wire construction is used primarily in the laboratory where close accuracy is required. In a 4 wire RTD the actual resistance of the lead wires can be determined and removed from the sensor measurement. The 4-wire circuit is a true 4-wire bridge, which works by using wires 1 & 4 to power the circuit and wires 2 & 3 to read. This true bridge method will compensate for any differences in lead wire resistances

Thermistors differ from resistance temperature detectors (RTD) in that the material used in a thermistor is generally a ceramic or polymer, while RTDs use pure metals. The temperature response is also different; RTDs are useful over larger temperature ranges, while thermistors typically achieve a higher precision within a limited temperature range, typically −90 °C to 130 °C

Flow

Flow measurement is the quantification of bulk fluid movement.Factors Affecting Flow rate

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Velocity of Fluid viscosity of Fluid Density of Fluid Friction of Fluid with pipe

Measuring Techniques Pressure-based meter

There are several types of flow meter that rely on Bernoulli's principle, either by measuring the differential pressure within a constriction, or by measuring static and stagnation pressures to derive the dynamic pressure.

FLOW TRANSMITTER:

In Byco, almost all the pressure transmitter are based on differential pressure measurement and then extracting the actual flow of the liquid passing from them.

The figure show is a type of FT used in Byco. There are two openings, one is connected to upstream of the vessel while other is inserted at the down side to create differential pressure situation. The two wire loop system is used. There is a purge screw to release access pressure manually and isolation valve to isolate it from the line.Difference of pressure is created by following.

1. Orifice PlateAn orifice plate is a plate with a hole through it, placed in the flow; it constricts the flow, and measuring the pressure differential across the constriction gives the flow rate. It is basically a crude form of Venturi meter, but with higher energy losses. There are three type of orifice: concentric, eccentric, and segmented.

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CONTROL VALVESControl valves are valves used to control conditions such as flow, pressure, temperature, and liquid level by fully or partially opening or closing in response to signals received from controllers that compare a "set point" to a "process variable" whose value is provided by sensors that monitor changes in such conditions.[1]

The opening or closing of control valves is usually done automatically by electrical, hydraulic or pneumatic actuators. Positioners are used to control the opening or closing of the actuator based on electric or pneumatic signals. These control signals, traditionally based on 3-15psi (0.2-1.0bar), more common now are 4-20mA signals for industry, 0-10V for HVAC systems, and the introduction of "Smart" systems, HART, Field bus Foundation, and Profibus being the more common protocols.

A control valve consists of three main parts in which each part exist in several types and designs:

Valve's actuator Valve's positioner Valve's body

Types of control valve: There are two basic types of control valves.

a) Rotary motion valves having ball, butterfly or plug type closures.

b) Linear motion valves having globe, diaphragm or pinch type closures.

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Control Valve Classification

Diaphragm ValvesFeaturesConsists of a saddle or seat upon which the diaphragm closes the valvesCan handle corrosive fluidsApplicationsUsed as shut off valves in food and beverage, pharmaceutical and biotech industries

Ball ValveFeaturesTight Shut OffMinimum obstruction for the flowing mediaHigh flow capacityCan withstand high pressure and temperaturesApplicationsUsed for hazardous and corrosive fluids

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Ball

Butterfly ValveFeatures:High flow capacityUnlike ball valve the disc is present in the flow of the liquid and hence a pressure drop is always induced in the flow. Tight shut offApplications:Used in Steel, Sugar and textile industries

Pressure Safety valve (PSV): Pressure Safety valve is a safety device to prevent bursting that caused by pressure equipment and container or easy to cause pressure rise or the container internal pressure exceeds the limits. Safety valve is a safety device that is widely used in pressure vessel, boiler, pressure piping and other pressure systems, to ensure the safe operation of pressure systems. When the container pressure exceeds the design requirements, the safety valve automatically opens, accompanied by a popping sound, the escaping gas reduces internal over pressure, to prevent the container or pipeline damage. And when the internal pressure reduces to normal operating pressure, the container automatically shuts down to avoid over-pressure exhaust all the gas, lead to waste and production suspensionThe term safety valve should be limited to compressible fluid applications (gas, vapor, or steam).

Temperature relief valves:Temperature relief valves, also known as temperature and pressure valves or T&P valves, are used to prevent the dangerous buildup of water, vapor and gas pressure inside of a hot water heater. A metal valve, typically brass or steel, is screwed into a special outlet on the side or top of the tank. The valve releases pressure, preventing the tank from leaking or exploding.

The residual steam and heat must be released to allay the threat of damage to the tank, pipe bursts or explosion, that’s why, Byco uses them in LPG Bullets.

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OIL MOVEMENT Oil movement department consists of transferring the crude from decanting to storage tanks then to process area and then to the shipment region from where it is supplied.

In Byco, there are three section of Oil Movement,1. Decanting2. Shipment3. Tanks

Crude is supplied from decanting region to storage tanks where it is stored. Then sample crude is sent to the laboratory for BS & W (Bottom sediments and water) test. After successful result, crude flows into the pre flash tower through a chain of pipes and pumps. From Pre flash it is sent to the crude distillation unit for further treatment. After completion of distillation process crude is sent to the crude separator to separate water from crude. Separated water is then drowned into the sea and the crude is stored in storage tanks in its different forms.

According to engineering point of view, the main task of oil movement department is,1. Planning:

When Crude comes to the decanting area, the tanks are designated in which the crude is stored.

2. Monitoring3. Material balancing:

The crude required is properly measure before and after receiving from third party.

OPERATION OF OIL MOVEMENT:The operation of oil movement department is mainly focuses on,

1. Inter Tank Transferring2. Plant Feed3. Transport4. Rundown

STORAGE TANKS:Storage tanks available at BYCO are used for storing crude before and after the processing. Storage tanks of 70 to 85 diameters are available at BPPL. Storage tanks consist of steel pipes that are provided for the filling or discharge of crude. There are 37 tanks, 6 for crude while remaining for product storage.

There are three types of tanks at BPPL:

3. Internal floating roof4. External floating roof5. Fixed roof

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LPG BULLETS:LPG bullets are cylindrical and horizontal containers used for storing Liquefied petroleum gas. Similar types of LPG bullets are stored at BPPL for storing huge amounts of liquefied petroleum gas.

PUMPS:There are booster pumps and feed pumps are installed at BPPL. All pumps are centrifugal type. Booster pumps are used for pumping crude from the tanks to the process area where as feed pumps are used for pumping the crude with in the process area.

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CONCLUSIONThroughout my Internship tenure at BYCO Petroleum Pakistan Limited, I was fortunate to work amongst a number of outstanding and remarkable people, who constantly guided me throughout my work with their valuable comments, teaching and positive criticism. Unable to completely express my gratitude to those all people, I dearly thank them all for guiding me and making my Internship a success.

Thank You

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