Jawaharlal Nehru Technological University Kakinada

    

Prof. K. V. RaoProgramme DirectorPetroleum Courses

JNTUK

B. Tech. Petrochemical Engineering

Petroleum Refinery Engineering

University College of Engineering (A) KakinadaDept. of Petroleum Engineering & Petrochemical Engineering

Petroleum Distillation ProductsFraction

Size Range BP Range (oC) Uses

Gas C1 - C4 0 - 30 Gas Fuels

Gasoline C4 - C12 30 - 200 Motor Fuels

Kerosene C12 - C16 180 - 300 Jet fuel, diesel oil

Gas – oil C16 - C18 >300 Diesel fuel, cracking stock

Lubricating Stock C18-C20 >350 Lubricating oil,

cracking stock

Paraffin wax C20-C40 Low-melting solids

Candles, wax paper

Asphalt > C40 Gummy residues

asphalt, roofing tar

Lube Oils

ATM

OSP

HE

RIC

TO

WE

R

REDUCED CRUDE OILTO LUBE REFINERY

FUEL REFINERY PROCESS

CRUDE OIL

LAN

SKO

HAN

LGOHGO

LPG

VAC

UU

M

TOW

ER

NM

PEX

TRA

CTI

ON

PRO

PAN

ED

E

ASP

HA

L-

TIN

G

BITUMEN

150 SS500 SS

1300 SS

75 SS/ SPINDLE

RPO(AROMATICEXTRACTS)

DEW

AX

ING

UN

IT

BRIGHT STOCK

WAX

HY

DR

OFI

NER

150 BS

1300 N

500 N150 N75 SM

RCO

LUBE REFINING

BASE OIL TERMINOLOGY• LUBES ARE HIGH VALUE PRODUCTS WITH BROAD VARIETY OF

USES

– Automotive: Engine oils, Automatic Transmission Fluids (ATF)

– Industrial: Turbine oils, Hydraulic oils, Industrial Gear oils, Compressor oils,

Refrigeration oils, Machine oils, Electrical oils, Drilling Fluids etc

– Medicinal: Food Grade oils, White oils,..

• REFINERIES PRODUCE BASE OILS OR BASE STOCKS– Finished Products are Blends of Base stock with(out)

Additives

BASE OIL TERMINOLOGY

• BASE STOCKS ARE CALLED BY VARIOUS NAMES:– Neutrals (100N, 150N, 600N,...) Bright Stocks– Grades (SAE 5, 10, 30, ..; ISO 22, 32,...)

• MOST COMMON LUBE NAME IS NEUTRAL– Number is the Viscosity @ 40 or 100oC

• BRIGHT STOCK IS HEAVY LUBE PRODUCED FROM RESIDUE– Name Refers to Appearance and Typical Viscosity is

2,500 SSU @ 100oF

• GRADE NAMES MAY REFER TO VISCOSITY OR TO TRADEMARKS

BASESTOCK PROPERTIES AND DEFINITIONS• BASE STOCK COMPOSITION DETERMINES PERFORMANCE

OF FINISHED PRODUCTS

– Viscosity Index or VI• Higher VI improves Volatility, Fuel Economy, and

Operating Range

– Saturate Content• Higher Saturates improves Oxidation Stability and

Soot Handling

– Wax Content• Lower Wax Improves Operating Range• Lower Wax improves Low Temperature

Performance– Pour Point– Cloud Point

BASESTOCK PROPERTIES AND DEFINITIONSBase oil groups

• Group I – Saturates <90% and/or sulfur >0.03%, and Society of Automotive Engineers (SAE) viscosity index (VI) of 80 to 120Manufactured by solvent extraction, solvent or catalytic dewaxing, and hydro-finishing processes. Common Group I base oil are 150SN (solvent neutral), 500SN, and 150BS (brightstock)

• Group II – Saturates over 90% and sulfur under 0.03%, and SAE viscosity index of 80 to 120Manufactured by hydrocracking and solvent or catalytic dewaxing processes. Group II base oil has superior anti-oxidation properties since virtually all hydrocarbon molecules are saturated. It has water-white color.

BASESTOCK PROPERTIES AND DEFINITIONS

• Group III – Saturates > 90%, sulfur <0.03%, and SAE viscosity index over 120Manufactured by special processes such as isohydromerization. Can be manufactured from base oil or slax wax from dewaxing process.

• Group IV –Polylphaolefins(PAO)

• Group V – All others not included above such as naphthenics, PAG, esters.

In North America, Groups III, IV and V are now described as synthetic lubricants, with group III frequently described as synthesised hydrocarbons, or SHCs. In Europe, only Groups IV and V may be classed as synthetics.

BASESTOCK PROPERTIES AND DEFINITIONS

The lubricant industry commonly extends this group terminology to include:

• Group I+ with a Viscosity Index of 103–108• Group II+ with a Viscosity Index of 113–119• Group III+ with a Viscosity Index of at least 140

Can also be classified into three categories depending on the prevailing compositions:

• Paraffinic• Naphthenic• Aromatic

KEY LUBE OIL PROPERTIES• VISCOSITY (MEASURE OF FLUIDITY)

– Range from ~ 4 to 20 cSt @ 100oC for Neutrals up to 32 cSt for Bright Stock

– Brookfield Measures Low Temperature Fluidity on Finished Oils @ -40oC

• VISCOSITY INDEX (INVERSE MEASURE OF CHANGE OF VISCOSITY WITH TEMPERATURE)– Ranges from ~85 to ~105 for most Base stocks, Higher for

Speciality Grades– (ex: Exxsyn ~140, PAO ~150, XHVI~140+, Ultra S ~ 125)

• POUR POINT (TEMPERATURE AT WHICH FLUID BECOMES NEARLY SOLID)– Typically from -9 to -24oC– Cloud Point is Temperature at Which Wax Crystals Appear

KEY LUBE OIL PROPERTIES

• VOLATILITY (MEASURE OF OIL LOSS DUE TO EVAPORATION)– Noack Volatility Measures Actual Evaporation (Typically

20-35 wt%)– GCD Volatility Measures Front End of Boiling Curve (e.g

10% @375oC)

• COLOR (APPEARANCE) AND STABILITY (MEASURE OF COLOR CHANGE IN LIGHT)

• CONRADSON Carbon (MEASURE OF CARBON RESIDUE LEFT ON IGNITION)

• SATURATES, AROMATICS and ASPHALTENE CONTENTS

INDIAN LUBE REFINING CAPACITY

» TMTPA

• HPCL, Mumbai - 330• IOC,Haldia - 200• CPCL, Chennai - 240• BPC, Mumbai - 180• TOTAL - 950

LUBE MANUFACTURING

Lube Refinery

Blending Plants

Function

Base Oils

Viscosity IndexPour PointFlash Point

Lubricants

ImprovedImprovedNo change

Oxidation Stability

Additives

Key Properties

CUSTOMERS

Special Properties

GENERAL CATEGORIES

AUTOMOTIVE LUBRICANTS

INDUSTRIAL LUBRICANTS

GREASES SPECIALTIES

ENGINE OILSTRANSMISSION OILS

TURBINE OILSHYDRAULIC OILSCOMPRESSOR OILSREFRIGERATION OILSSPINDLE OILSCYLINDER OILSGEAR OILSTEXTILE OILS etc

WHEEL BEARINGCHASSISINDUSTRIAL

CUTTING FLUIDSMETAL ROLLING OILSRUBBER PROCESS OILSRUST PREVENTIVESHEAT TRANFER FLUIDSMETAL DRAWING COMPOUNDSQUENCHING OILS etc

FUNCTIONS OF ENGINE OILS

o PERMIT EASIER STARTING

o LUBRICATE AND PREVENT WEAR

o REDUCE FRICTION

o PROTECT AGAINST RUST AND CORROSION

o KEEP ENGINE INTERIORS CLEAN

o COOL ENGINE PARTS

o SEAL COMBUSTION PRODUCTS

o BE NON-FOAMING

o AID FUEL ECONOMY

TECHNICAL SPECIFICATIONSPARAMETERS ASTM 60N 100N 150N 500N 600N 150BS

Specific Gravity, 15/4°C D1298 0.8773

0.8520

0.8666

0.8811

0.8817 0.8940

Colour, Say bolt D1500 L0.5 L0.5 L1.0 L2.0 L1.5 L2.0Kinetic Viscosity @40,cSt

D4457.498 20.31 30.14 95.79 115 480.6

  @100,cSt

  2.036 4.166 5.189 10.97 12.43 31.32

Viscosity Index D2270 66 107 101 99 97 98Flash Point, °C(COC) D92 156 208 212 242 253 310Pour Point, °C D97 -20.0 -15.0 -12.5 -12.5 -12.5 -12.5

TECHNICAL SPECIFICATIONSPARAMETERS ASTM 60N 100N 150N 500N 600N 150BS

Sulphur Content, wt ppm D5453 <10 <10 <100 <100 <100 <100Carbon Residue(CCR), wt% D189 <0.01 0.01 0.04 0.01 0.01 0.01Copper Corrosion, 100°C/3hr D130 1a 1a 1a 1a 1a 1aTAN, mgKOH/g D974 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01Ring Analysis, wt%CA   8.4 2.2 1.8 7.2 6.4 7.3  wt%CN D3238 42.5 29.4 32.1 26.0 26.5 21.7  wt%CP   49.1 68.4 66.1 66.8 67.1 71.0Aniline Point, °C D611 77.8 107.0 107.1 116.3 116.9 129.7

GREASES

BASE OIL + THICKENER + ADDITIVES

MINERAL SOAP ANTI-OXIDANT

• COMPOSITION

WHY USE A GREASE?• A GREASE OFFERS UNIQUE CHARACTERISTICS WHICH

MAKES IT PARTICULARLY USEFUL IN MACHINE ELEMENTS

STAY WHERE IT IS PUTALLOWS UNATTENDED SERVICE FOR LONG PERIODS (SEALED FOR LIFE)REQUIRES LESS FREQUENT APPLICATION FOR AREAS

OF POOR ACCESSIBILITY SEALS OUT CONTAMINANTSOPERATE OVER A WIDE TEMPERATURE RANGE SOLID ADDITIVES CAN BE USED WITHOUT CONCERN OF SETTLING OUT LOW LEAKAGE MEANS THEY ARE EFFECTIVE IN WARM

EQUIPMENT

NLGI CLASSIFICATION OF GREASESNATIONAL LUBRICRATING GREASE INSTITUTE

NLGI NO. ASTM PENETRATION @ 25O oC*1 310-3402 265-2953 220-2504 175-2055 130-2606 85-115

* After working 60 strokes.

Petroleum Wax

• General features of wax– Solid at ambient temperature – Thermoplastic in nature – Combustible – Liquid at 100 to 200°F – Insoluble in water

3 general categories of petroleum wax • Paraffin waxes : from the light lubricating oil

distillates, contain straight-chain HC with an average chain length of 20 to 30 carbon atoms.

• Microcrystalline waxes (micro wax): from a combination of heavy lube distillates and residual oils. have poorly defined crystalline structure, darker color, and higher viscosity and MP. Vary much more widely than paraffin waxes with regard to physical characteristics.

• Petrolatums from heavy residual oils and are separated by a dilution and filtering (or centrifuging) process. Petrolatums are microcrystalline in nature and semi-solid at room temperature.

Other terms used to refer to petroleum wax: refering to the amount of oil contained in the product.

• Slack wax containing anywhere from 3 to 50% oil content.

• Scale wax containing 1 to 3% oil content. • Fully refined paraffin (FRP) wax having less

than 0.5% oil content. THe wax that has had nearly all of the oil refined out of it.

26IHPT 2008 Petro.

Wax PropertiesProperty Test Method Description Typical Values

Melt Point ASTM D87 Provides information on temperature atwhich most of a given wax changes froma solid to a liquid. Widely used forparaffin waxes.

100-160 OF (43-71 OF) forparaffin waxes from a solid to aliquid.

CongealingPoint

ASTM D938 Measures when a wax ceases to flow. Varies widely

Drop Melt PointASTM D127 Generally used on waxes that don’t showa melting plateau e.g. petrolatums andmicrocrystalline waxes.

140-200 OF (60-93 OC) formicrocrystalline waxes

NeedlePenetration

ASTM D1321Measures the hardness of wax. Usuallydetermined at 77 OF (25 OC) or 100 OF.Higher values indicate softer wax.

9-20 (0.1dmm) for paraffin @ 77OF (25 OC)

Oil Content ASTM D721 The amount of oil in wax. Indicatesdegree of refining

Fully Refined <0.5%, Semi-refined 0.5-1.0%, Scale 1.0-3.0%

• http://www.igiwax.com/resource/Test_Methods

• Oil content in wax (ASTM-D721)

• Oil content or solvent extractables in wax can affect key properties such as strength, hardness, melting point, etc.

• ASTM-D721

HEAVY FUEL OILS

HEAVY FUEL OILS

Heavy fuel oil consists primarily of the residue from distillation or cracking units in the refinery.

Historically, fuel oils were based on long residues from the atmospheric distillation column and were known as straight run fuels.

However, the increasing demand for transportation fuels such as gasoline, kerosene and diesel has led to an increased value for the atmospheric residue as a feedstock for vacuum distillation and for cracking processes.

As a consequence, most heavy fuel oils are currently based on short residues and residues from thermal and catalytic cracking operations.

These fuels differ in character from straight run fuels in that the density and mean molecular weight are higher, as is the carbon/hydrogen ratio.

The density of some heavy fuel oils can be above 1,000 kg/m3, which has environmental implications in the event of a spillage into fresh water.

In refineries with catalytic cracking units, catalytically cracked cycle oils are common fuel oil diluents.

As a result, the composition of residual fuel oils can vary widely and will depend on the refinery configuration, the crude oils being processed and the overall refinery demand.

Residual fuel oils are complex mixtures of high molecular weight compounds having a typical boiling range from 350 to 650°C.

They consist of aromatic, aliphatic and naphthenic hydrocarbons, typically having carbon numbers from C20 to C50, together with asphaltenes and smaller amounts of heterocyclic compounds containing sulphur, nitrogen and oxygen.

They have chemical characteristics similar to asphalt and hence, are considered to be stabilised suspensions of asphaltenes in an oily medium.

Asphaltenes are highly polar aromatic compounds of very high molecular weight (2000-5000) and in the blending of heavy fuel oils, it is necessary to ensure that these compounds remain in suspension over the normal range of storage temperatures.

Heavy fuel oils also contain organo-metallic compounds from their presence in the original crude oils. The most important of these trace metals is vanadium.

Some crude sources, for example, from the Caribbean area and Mexico are particularly high in vanadium and this is reflected in high vanadium contents in heavy fuel oils produced from these crudes.

Vanadium is of major significance for fuels burned in both diesel engines and boilers because when combined with sodium (perhaps from seawater contamination) and other metallic compounds in critical proportions it can form high melting point ashes which are corrosive to engine exhaust valves, valve seats and super heater elements.

Other elements that occur in heavy fuel oils include nickel, iron, potassium, sodium, aluminium and silicon.

Aluminium and silicon are mainly derived from refinery catalyst fines.

Significant concentrations of hydrogen sulphide (H2S) are known to accumulate in the headspaces of storage tanks that contain heavy fuel oils.

Heating of such tanks may cause decomposition of some of the sulphur-containing compounds, which release H2S.

In addition to the hazard from H2S, there is also evidence that accumulations of vapours of light hydrocarbons are also to be found in the headspaces of heavy fuel oil tanks.

Appreciable concentrations of polycyclic aromatic compounds (PAC) can be present in heavy fuel oils depending on the nature and amount of the low viscosity diluent used and whether the residue component is cracked or un-cracked.

If the residue components are from the atmospheric or vacuum distillation columns, the concentration of three to seven ring aromatic hydrocarbons is likely to be in the order of 6 to 8%; if heavy catalytically cracked or steam-cracked components are used, the level may approach 20% .

One of the diluent fractions commonly used is catalytically cracked cycle oil, which has been reported to contain 58% three to five ring aromatic hydrocarbons .

HEAVY FUEL OIL BLENDING COMPONENTS.

Heavy fuel oils can be blended from a wide range of refinery components, the most important of which are:

Long residue: the residue from the atmospheric distillation of crude oil. As mentioned earlier, historically this was a major fuel oil blending component, but it is now mainly used as a feedstock for the vacuum distillation unit or for a thermal or catalytic cracking unit.

Short residue: the residue from the vacuum distillation of crude oil.

Thermal cracker or visbreaker residue: the residue from thermal cracking processes designed to increase the yield of distillate components from atmospheric and vacuum residues.

Cat cracker slurry oil (clarified oil): a heavy fraction from a catalytic cracking operation, a process for the conversion of heavy hydrocarbon fractions into high quality gasoline components.

Thermally cracked or visbreaker gas oil: a middle distillate fraction from thermal cracker or visbreaker units.

Cat cracker cycle oil: a middle distillate fraction from the catalytic cracking unit.

Kerosine: a lighter middle distillate fraction from the atmospheric column.

Gas oil: a heavier middle distillate fraction from the atmospheric column.

Vacuum gas oil: a heavy gas oil fraction from the vacuum column.

TYPICAL PROPERTIES

Marketing specifications have been established by a number of authorities to ensure the satisfactory operation of industrial and marine equipment utilising heavy fuel oils.

Such specifications include ASTM D-396 (ASTM 1992), BS 2869 for inland fuels (BSI 1988), ISO 8217 for marine fuels (ISO 1996) and CIMAC requirements for residual fuels for diesel engines (CIMAC 1990).

Typical properties for heavy fuel oils can vary widely within the specification limits:

normally they would be expected to fall within the ranges listed in Table 1.

Table 1: Range of physico-chemical properties for heavy fuel oils

Thank You