NDUSTRIAL INTERNSHIP at Numaligarh Refinary Limited (NRL),Golaghat-Assam

This presentation explores my internship experience at a leading oil refinery, where I engaged in various stages of the refining process, including crude oil distillation, catalytic cracking, and quality control. Key highlights include an overview of refinery operations, hands-on learning about energy management, equipment maintenance, and safety protocols in the oil and gas industry.

1. Numaligarh Refinery Limited
Industrial Internship
At
J O R H A T E N G I N E E R I N G C O L L E G E
(INSTRUMENTATION DEPARTMENT)
•DebabratBorah
•HimalayMoran
•NiveaBuragohain
•SabrinaSultanaChoudhury
•MrigankaMudai
•PritomRanaDas
Presented By -

2. CONTENTS
❑INTRODUCTION TO NRL
❑OBJECTIVES OF NRL
❑OVERVIEW OF NRL
❑FIRE AND SAFETY
❑AREA COVERED BY INSTRUMENTATION DEPARTMENT
❑INSTRUMENT’S OBSERVED IN VARIOUS PLANTS
❑CALIBRATION
❑PLC AND DCS

3. INTRODUCTION
▪NRL was established in 1993 as a public sector undertaking(PSU).
▪NRL is one of India’s Largest Oil refining and marketing companies.
▪NRL is owned 61.65% by BCPL, 26% by OIL and 12.35% by Government of Assam.
▪NRL is situated in Numaligarh , Golaghat district of Assam, India. This 3750 Cr. refinery
spread across 750 acres surrounded by green tea gardens.
▪The refinery’s primary function is to refine crud oil to produce various petroleum
products such as petrol, diesel, LPG, ATF(aviation turbine fuel) etc.
▪It has a refining capacity of 3 million matric tons per annum(MMTPA).

4. OBJECTIVES
▪To process crude oil available in the North-East region.
▪To meet the short fall in major products in the North East region to help in
country’s effort to meet the requirements of the middle distillates to the
maximum extent possible through indigenous sources.
▪To introduce the latest process technology for secondary processing as well as
up gradation of residue/heavier ends.
▪To adapt measures /technology for energy efficient systems in refinery.
▪To generate direct and indirect employment and to increase industrial growth
economically backward North-East region.
▪Focus on development and growth of human resources through proper training
and carrier planning.

5. ❑OVERVIEWOFNRL
❑Major Units Of NRL –
▪Crude distillation Unit (CDU)
▪Vacuum distillation Unit (VDU)
▪Delayed Coker Unit (DCU)
▪Hydrocracker Unit (HCU)
▪Hydrogen Unit (H2U)
▪Coke calcinations Unit (CCU)
▪Sulphur Recovery Block (SRB)
▪Motor Spirit Plant (MSP)
▪Solvent De-oilingUnit(SDU)
▪Hydrogen Fixing Unit (HFC)
❑Products –
▪Liquefied Petroleum Gas
(LPG)
▪Naphtha
▪Motor Spirit (MS)
▪Aviation Turbine Fuel
(ATF)
▪Superior Kerosene Oil
(SKO)
▪High Speed Diesel (HSD)
▪Raw Petroleum Coke
(RPC)
▪Calcined Petroleum Coke
(CPC)
▪Sulphur
▪Wax

6. ❑RefineryConfiguration
e
Block Flow Diagram -NRL

7. ❑FireandSafety
•Firesafetyisthesetofpracticesintendedtoreducethedestructioncausedbyfire.
•Afirerequiresthreevariablestoinitiate:afuel,oxygen,andheat.Thefiretriangleisawell-
knownrepresentationofthethreevariablesneededtoinitiateafire.Inordertoinitiateafire,
fuel,oxygen,andheatarerequired.
•Firesareclassifiedbaseduponthetypeoffuelthatisconsumed.Firesareclassifiedintocategoriesso
personnelcanquicklychooseappropriateextinguishingagentsfortheexpectedfireandassociated
hazards.TheFiveclassesoffireare–class-A,class-B,class-C,class-D,class–K.
•Firepreventionrequiressegregatingthethreeelementsofthefiretriangle.Afireneedsthreeelements-
heat,oxygenandfuel.Withoutheat,oxygenandfuela
firewillnotstartorspread.Akeystrategytopreventfire
istoremoveoneormoreofheat,oxygenorfuel.
Easy acronym when using an extinguisher –PASS

8. ❑AreacoveredbyInstrumentationDepartment
▪Calibration and servicing
▪Public Address(PA) system
▪Very High Frequency(VHF)
system
▪Fire Alarm (FA)
▪CCTV system
▪Analyzer system
▪Gas Detector system
▪Clean Agent System
▪RIM seal system
▪Lab Instruments
➢INSTRUMENTATION WORKSHOP -
▪Crude and Vacuum Distillation
Unit(CDU/VDU)
▪Delayed Coker Unit (DCU)
▪Hydrogen Unit(H2O)
▪Hydrocracker Unit(HCU)
▪Sulphur Recovery Block(SRB)
▪Coke Calcination Unit (CCU)
▪Motor Spirit Plant (MSP)
▪Naphtha Splitter Unit (NSU)
▪Solvent De-oiling Unit (SDU)
▪Hydrogen Fixing Unit (HFU)
▪Numaligarh Refinery Marketing
Terminal (NRMT)
➢CENTRAL CONTROL ROOM (CCR) -

9. ❑AreacoveredbyInstrumentationDepartment
▪Gas Turbine
▪Steam Turbine
▪Utility Boiler (UB)
▪Heat Recovery Steam Generator (HRSG)
▪Effluent Treatment Plant (ETP)
▪Raw Water Pump House (RWTP)
▪Fire Water Pump House (FWPH)
▪Nitrogen Plant (N2P)
▪Raw Water Intake Plant
➢POWER PLANT AND UTILITY -

10. ❑Instrument’s Observed In Various Plants
➢PRESSURE RELATED INSTRUMENT’S :
AIR COMPRESSOR
Aircompressorisadevicethatconvertpowerintoanpotentialenergystoredin
pressuredair.InNRLaircompressor’sarewidelyusedinvariousapplicationstoprovidepower,
controlandsafetythroughoutrefineryoperations.
Thecompressedairpowerspneumaticinstruments,controlvalvesandcontrollers,
whichregulateprocessacrosstherefinery.Whichhelps
tomanageflows,pressureandtemperaturesinreal-time
withouthumanintervention.Compressedairisused
forcleaningequipment,pipelines,vesselsetc.Alsousedto
calibratepressuremeasuringinstrument’s.

11. ❑Instrument’s Observed In Various Plants
➢PRESSURE RELATED INSTRUMENT’S :
PRESSURE GAUGE
Apressuregaugeisamechanicalinstrumentusedtomeasure
thepressureexertedbyafluid(liquidorgas)onitssurrounding
environment.Thebasicworkingprincipleofapressuregaugeinvolves
asensingelement(suchasadiaphragm,Bourdontube,orbellows)
thatdeformsinresponsetothepressureapplied.Thisdeformationis
convertedintomechanicalmotion,whichisthentransmittedtoapointer
onacalibratedscale.Aspressureincreasesordecreases,thesensing
elementmoves,therebyindicatingthecorrespondingpressurereading
onthegauge'sdial.Thisisusedforrealtimepressuremeasuring
purposeinNRL.

12. ❑Instrument’s Observed In Various Plants
➢PRESSURE RELATED INSTRUMENT’S
PNEUMATIC PRESSURE CONTROLLER
Pressurecontrollerisbasicallyusedincontrolvalveopeningandclosingoperationwhich
finallycontrolstheprocessvariablelikepressure,temperature,leveletc.InNRL,Pneumatic
PressureControllersareessentialforpreciouscontrolandregulationofpressureinvarious
systemsandprocess.Thepartsofapressurecontrollerare–DiaphragmorBellows,Bourdon
Tube,FlapperNozzleassembly,Pointerunit,BoosterRelay,setpoint
adjusterwithsupplyairinletandoutputsignalport.Itworksbysens-
ingpressurechangesinsyst-emandadjustingittoapresetlevel
(setpoint)usingabellows/diaphragm.Whenthepressuredeviates
fromsetpointthecontrollersensespressurechangesandadjusts
airflowtocontrolvalves,keepingthesystempressureatasetpoint.

13. ❑Instrument’s Observed In Various Plants
➢PRESSURE RELATED INSTRUMENT’S :
PNEUMATIC VALVE POSITIONER
ThePneumaticValvePositionerisaninstrumentworkingon
forcebalanceprincipletopositiontheControlValvesteminaccordance
toapneumaticsignalreceivedfromacontrollerormanualloading
station,regardlessofpackingboxfriction,actuatorhysteresisor
unbalancedforcesonthevalveplug.Thus,thepositionerensuresa
reliableandaccurateoperationofControlValve.Inrefinery,this
instrumentimprovesresponsetime,stabilityandallowspreciousflow
control,whichiscriticalformanagingprocessparameterslikepressure,
Temperature,andflowratesincomplexandhigh-riskenvironments.

14. ❑Instrument’s Observed In Various Plants
➢PRESSURE RELATED INSTRUMENT’S :
DIFFERENTIAL PRESSURE TRANSMITTER (DPT)
ADPTmeasuresthepressuredifferencebetweentwo
pressurepointsandthenconvertitintoanelectricalsignal.Thereare
mainlythreepartsinDPT–
▪PressureSensingElement:Twopressuresensingelementsare
locatedatthebottomoftheDPT,whichismarkedasHighand
Low.Thediaphragmislocatedbetweenthistwopoints.The
diaphragmdeflectaspressureappliedbetweentwopoints.
▪ElectricalCircuit–Itconvertthepressureintoverylowvoltage(in
millivolt.).Thissignalneedtobeamplifiedandthenconverted
into4-20mA.
▪4-20mACurrentTransmitter–Theelectricalsignal4-20is
importanttodisplaythepressureorapplythepressuretotheother
unitlikePLC,Closeloopcontrolleretc.

15. ❑Instrument’s Observed In Various Plants
➢TEMPERATURE RELATED INSTRUMENT’S :
TEMPERATURE GAUGE
Atemperaturegaugeconsistofasensingelementlike
thermocouple,bimetallicstriporthermistorwhichdetectstemperature
changes.Thesensingelementisconnectedtoanindicatorordialthat
displayreal-timetemperaturereading.
InNRL,temperaturegaugesareessentialtomonitorandcontrol
thetemperatureinvariousprocess.Theseinstrumentsensurethat
temperaturestaywithinoptimalrangesforsafeandefficientoperation.
▪THERMOCOUPLE :Itconsistsoftwodissimilarelectricalconductorsto
formelectricaljunctionatdifferenttemperature.Itworkingprinciple
basedonseabackeffect,whenthereisatemperaturedifference
betweentheirjunctionsanelectricalvoltageisinducedacrosstheclosed
circuit.Types:J,K,N,R,Tetc.

16. ❑Instrument’s Observed In Various Plants
➢TEMPERATURE RELATED INSTRUMENT’S :
RESISTANCE TEMPERATURE DETECTOR(RTD)
RTDsareknownfortheiraccuracy,stabilityand
repeatabilityinindustrialapplications.AnRTDoperatesbasedon
theprinciplethatametal’selectricalresistancechangeswith
temperature.Asthetemperatureincreases,theresistanceofthe
RTD’smetalelement,usuallyplatinum,alsoincreasesina
predictable,linearmanner.Bymeasuringthisresistance,the
temperaturecanbeaccuratelydetermined.InNRLmostlyused
RTDisPT-100.
▪PT-100-PT-100RTDisaplatinumresistancetemperature
detectorwithastandardresistanceof100ohmsat0°C.ThePT-
100'sresistanceincreasesbyapproximately0.385ohmsper
degreeCelsius,makingitreliableforprecisetemperature
measurementsinindustrialsettings.

17. ❑Instrument’s Observed In Various Plants
➢FLOW RELATED INSTRUMENT’S :
CONTROL VALVE
Acontrolvalveisafinalcontrolelementusedtoregulatethe
flowbyvaryingthesizeoftheflowpassageinresponsetoacontrol
signal.VarioustypesofControlValves–Ballvalve,Glovevalve,
ButterflyValveetc.
Air-actuatedvalvesarecommonlyusedinNRLbecausethey
onlyrequiredcompressedairsupply.Whereaselectricallyopened
valverequiredadditionalcomponentssuchassensors,controllers
,switchgearandhydraulicallyactuatedvalves,whichrequiredhigh
pressuresupplyandreturnlinesforthehydraulicfluid.

18. ❑Instrument’s Observed In Various Plants
➢FLOW RELATED INSTRUMENT’S :
CONTROL VALVE
▪Valve Actuator –Which moves the valve
modulating element such as ball or butterfly.
▪Valve Positioner –Which ensures the valve has
reached the desired degree of opening.
▪Valve Body –In which the modulating element
such as a plug, ball or butterfly is connect.
▪Control Action –
i.Air or Current to Open : The flow restriction
decrease with increased control action.
ii.Air or Current to close : The flow restriction
increase with increased control signal.

19. ❑Instrument’s Observed In Various Plants
➢FLOW RELATED INSTRUMENT’S :
SOLENOID VALVE
▪Asolenoidvalveisanelectromechanicalcontrollervalve.
▪ThesevalvesareusedinNRLtocloseopendistributeormixthe
flowinapipe.Mostlytwotypes–2wayvalveand3wayvalve.
▪Insolenoidvalvewhenanelectriccurrentpassesthroughthecoil,
itgeneratesamagneticfieldthatactivatesthesolenoid.The
magneticfieldmovesaplungerwithinthevalve,whichopensor
closesthevalveseat.
▪Symbolusedfortwowaysolenoidvalve-

20. ❑Instrument’s Observed In Various Plants
➢FLOW RELATED INSTRUMENT’S :
MAGNETIC FLOW METER
▪AmagneticflowmeterisamassorVolumaticflowmeterthatuses
electrodesconnectedtotheliquidsinatubeorpipe.
▪Theyhaveaabilitytomeasurehighpressureflowapplicationwithout
anyleakage.
▪ItoperatesbasedonFaraday'sLawofElectromagneticInduction,
whichstatesthatavoltageisinducedwhenaconductivefluidmoves
throughamagneticfield.
▪Components-
•ElectromagneticCoil:Generatesamagneticfield.
•Electrodes:Measureinducedvoltage.
•FlowTube:Wherethefluidflows.

21. ❑Instrument’s Observed In Various Plants
➢LEVEL RELATED INSTRUMENT’S :
GLASS LEVEL GAUGE
▪Level Indicators are widely used in NRL for visual level indication of
liquid’s in process equipment like storage tanks or process vessels
etc.
▪Glass level gauges are mounted parallel to the side of the tank to
form close loop by which the level of liquid in the tank is displayed in
the level gauge.
▪It is recommended to used isolation valve between gauge and tank to
isolate the gauge during maintenance.
▪Glass level gauges are simple , no calibration required . Also, reliable
and do not required any power supply.

22. ❑Instrument’s Observed In Various Plants
➢LEVEL RELATED INSTRUMENT’S :
ULTRASONIC LEVEL TRANSMITTER
▪Anultrasonicleveltransmitterusesultrasonicwavesto
determinethelevelinacontainerorvessel.Thetransmitter
sendahighfrequencysoundwavethattravelsthroughtheair
untilitreachesthesurfaceofmaterialbeingmeasured.This
wavereflectbackandanalyzed.Thetimeittakestoreached
andcomebackisusedtocalculatethedistancebetweenthe
transmitterandthesurfaceofthemeasuredmaterial.
▪InNRLtheyareusedinTanklevelmeasurement,process
controlandOverflowpreventionoftanks.

23. ❑Instrument’s Observed In Various Plants
➢LEVEL RELATED INSTRUMENT’S :
RADAR LEVEL TRANSMITTER
▪A radar level transmitter use radar technology to measure the level of
liquids or solids in a tank or container. It emits microwave signals that
reflect off the surface of the material, calculating the distance based on
the time it takes for the signals to return.
▪The two main techniques of radar level transmitter –
•Pulse Radar Technique : Pulse radar is a type of radar system that
transmits short pulses of radio frequency (RF) energy at regular
intervals. It measures the time taken for the pulses to travel to a target
and return, allowing it to calculate the distance to the target.
•Frequency Modulated Continuous Wave (FMCW) Technique : FMCW
radar continuously transmits a signal that varies in frequency over time
(frequency modulation). It measures the difference between the
transmitted and received signals to determine the distancetoatarget.
•In NRL ,they are used in storage tank and separators.

24. CALIBRATION
CalibrationistheprocessofconfiguringaninstrumenttoprovideAresult
forAsimplewithinAacceptablerange.Eliminatingorminimizingfactors
thatcauseinaccuratemeasurementsisAfundamentalaspectof
instrumentationdesign.

25. ❑CALIBRATION
➢Dead Weight Tester
▪Itisusedforpressuregaugecalibration.
▪DeadweighttesterisbasedontheprincipleofPascal’sLaw.
▪Itcalibratespressurebydeterminingtheweightofforce
dividedbytheareawheretheforceisapplied.
▪Itcalibratespressuregaugesbyusingaknownweightanda
pistontogenerateaprecisepressure.Thepressuregauge
tobecalibratedisconnectedtothedeadweighttester.The
pressuregaugemeasuresthepressureatwhichtheweight
isapplied.Ifthere'sadiscrepancy,thegaugecanbe
adjustedaccordingtothemanufacturer'sspecificationsto
ensureaccuratereadings.

26. ❑CALIBRATION
➢Hydraulic Pressure Calibrator :
▪Ahydraulicpressurecalibratorisaportabledeviceusedto
generateandmeasureprecisehydraulicpressurefortesting
andcalibratingpressuresensorsandgauges.
▪The two main parts of this calibrator –
a) Hand Pump : It manually generates pressure for calibration.
b) Pressure Gauge/Transducer : Provides accurate
pressure reading.
▪Theyareportable,preciseandeasyforusedcalibrator.
▪Theyareessentialtoolsformaintainingthereliabilityandsafety
ofpressuremeasurementsystem.

27. ❑CALIBRATION
➢Highway Addressable Remote Transducer (HART) Communicator :
▪AHARTCalibratorisaprecisiontoolusedfortheconfiguration,
calibration,anddiagnosticsofHART-enabledfieldinstrumentssuchas
pressure,temperatureandflowtransmittersandsensors.
▪ItoperatesusingtheHARTcommunicationprotocol,whichallowsfortwo-
waydigitalcommunicationoverstandard4-20mAanalogsignals.
▪Userscanconnectthecommunicatordirectlytothefielddevice,accessing
awiderangeofinformationincludingdevicestatus,configuration
parameters,anddiagnosticdata.
▪Theinterfacetypicallyfeaturesauser-friendlydisplaythatguides
techniciansthroughvariousfunctions,suchasadjustingsettings,
performinglooptests,andretrievingcalibrationdata.

28. ❑CALIBRATION
➢Temperature Calibration Bath :
▪Atemperaturecalibrationbathisacontrolledenvironmentusedtocalibrate
temperaturemeasurementdevices(thermometers,thermocouples,etc.)by
immersingtheminastabletemperaturemedium.
▪Thebathissettoaspecifictemperaturewithinthegauge’soperating
rangeandallowedtostabilize.Thegaugeisthenimmersedinthebath
alongsideareferencethermometer,whichprovidesanaccurate
temperaturereading.Bycomparingthegauge’sreadingstothoseofthe
referencethermometer,anyfaultcanbeidentifiedandadjustedas
necessary.
▪Thisprocessensuresthatthetemperaturegaugeisaccurateandreliable,
meetingrequiredstandardsforprecisioninmeasurement.

29. A Distributed Control System (DCS) is a control system
where the control functions are distributed throughout the system
rather than being centralized in one location.
Components of the DCS system:
1.Sensors
2.Actuators
3.Controllers
4.Communication Network
Flow of Information:
Data
Acquisition
Data
Processing
Control
Action
Operator
Interaction
Benefits of DCS:
1.Centralized Control
2.Enhanced Safety
3.Improved Productivity.
DCS Control Room
DCS

30. Programmable Logic Controllers (PLCs) are
industrial computers, with various inputs and outputs,
used to control and monitor industrial equipment based
on custom programming.
PLC operation stages:
INPUT
PROGRAM
EXECUTION
OUTPUT
PLC

31. RefineryNumaligarhExpansionProject
~NRL is expanding its refinery capacity from 3.0 MMTPA to 9.0 MMTPA.
~The refinery will process Arab Light and Arab Heavy crude oil (30:70 ratio).
~A 1640 km cross-country pipeline will be built from Paradip Port to Numaligarh
to transport the crude.

32. Product Quality
CONCLUSION
Refinery Units
and Processes
Environmental
Protection
Safety
Measures
Product Quality
We got the best opportunity to do
our 6 semester summer training
at Numaligarh Refinery Limited
for the month of July. We got to
explore the different units, see the
various products with different
properties of each products, their
separation process, production
processes, etc.

33. Thankyoufor
J O R H A T E N G I N E E R I N G C O L L E G E
YOUR ATTENTION DURING OUR PRESENTATION ON NRL INTERNSHIP EXPERIENCE.
YOUR ATTENTION AND FEEDBACK MEANS A LOT AND WE ARE GREATFUL FOR THE
SUPPORT IN OUR ACADEMIC JOURNEY.