fuels. refinery processes typical products product wt% gas 0.1 lpg 1.0 naphtha 9.7 atf / kerosene...

FUELS

REFINERY PROCESSES

TYPICAL PRODUCTS

PRODUCT WT%

• GAS 0.1

• LPG 1.0

• NAPHTHA 9.7

• ATF / KEROSENE 10.8

• HSD 24.3

PRODUCT WT%

• LDO 4.8

• FUEL OILS 17.8

• ASPHALT 9.7

• VACCUM DISTILLATES 18.5

• FUEL & LOSSES 3.0

REFINERY FUELS PRODUCTS

• PROPANE• LPG• GASOLINE (NORMAL)• GASOLINE (PREMIUM)• LOW AROMATIC NAPHTHA• HIGH AROMATIC NAPHTHA• AVIATION TURBO FUEL DEFENCE / COMMERCIAL• HIGH SPEED DIESEL• LIGHT DIESEL OIL• KEROSENE• FUEL OIL (NORMAL)• FUEL OIL (DEFENCE)• LSHS

GASOLINE - SPECIFICATIONSWHERE ARE WE GOING ?

• LEAD• BENZENE• SULFUR• VOLATILITY

– VLI– E 70, E 100, E 180– FBP– RESIDUE

• OXYGENATES• GUM CONTENT• OLEFINS• DENSITY• ANTI KNOCK INDEX• ENGINE TESTS

DIESEL - SPECIFICATIONSWHERE ARE WE GOING ?

• AROMATICS• POLY AROMATICS• CARBON RESIDUE• SULFUR• WATER CONTENT• OLEFINS• VISCOSITY• VOLATILITY (T 95) • HEATING VALUE• COMPONENT COMPATIBILITY• STABILITY • CETANE INDEX• LUBRICITY• OXIDATION STABILITY• ENGINE / RIG TESTS

WHY BEING DONE

• TIGHTER EMISSION NORMS

• CHANGES IN ENGINE DESIGNS

• CHANGES IN METALLURGY OF THE ENGINE

• USE OF CAT CONVERTORS

• FUEL EFFICIENCY

• INCREASED POWER

ALL THIS HAS LED TO

• DECREASED FUEL STABILITY

• DECREASED COMPATIBILITY

• INCREASED OCTANE REQUIREMENTS

• POOR DRIVEABILITY AND DURABILITY

• EXTENDED REFINERIES AND TECHNOLOGY OF REFINING TO MAXIMUM

SOLUTION ?

FUEL ADDITIVE

“HP DIESEL PLUS”&

“HP PETROL PLUS”

BENEFITS

• IMPROVED FUEL ECONOMY• FUEL INJECTION CLEANLINESS• IMPROVED FUEL STABILITY• REDUCED EXHAUST EMISSIONS• DISPERSANCY FOR INSOLUBLE GUM• IMPROVED LUBRICITY• CORROSION PROTECTION • PREVENTION OF STABLE FUEL WATER

EMULSIONS• REDUCTION IN FOAM

DIESEL SPECS

PROPERTY LI MI TS

CETANE NUMBER 48 MI N

CETANE I NDEX 45 MI N

DENSI TY @ 15°C 820 – 860

VI SCOSI TY @ 40°C 2 – 4.5

SULPHUR, % WT 0.25 MAX

LURI CITY 400 MAX

T 95, °C 370 MAX

DIESEL SPECSPROPERTY LI MI TS

FLASH POI NT, °C 32 MI N

CARBON RESI DUE 0.03 MAX

CFPP *

WATER CONTENT 0.50 MAX

OXI DATI ON STABI LI TY 25 MAX

ASH CONTENT 0.01 MAX

COPPER CORRI SI ON 1 MAX

* LOWER THAN LOWEST AMBIENT

HEAVY FUEL OIL SPECS

CHARACTERI STI C I S DG SET

ACI DI TY I NORG NI L -

ASPHALTENES, % WT 10 & 14 14 MAX

ASH CONTENT, % WT 0.1 MAX 0.2 MAX

CCR, % WT 15 & 20 22 MAX

POTENT SED, % WT - 0.1 MAX

WATER, % WT 1 MAX 1 MAX

Al + Si 80 MAX 80 MAX

CCAI - 850 MAX

HEAVY FUEL OIL SPECSCHARACTERI STI C I S DGSET

FLASH POI NT, °C 66 MI N 60 MI N

KI N VI SC @ 50°C 180 MAX 55 @ 100

TOTAL SED 0.25 MAX -

POUR POI NT, °C 30 MAX -

TOTAL SULPHUR 4 MAX 5 MAX

DENSI TY, 15°C 0.991 MAX 0.991 MAX

VANADI UM, ppm 300 MAX 50 - 600

SODI UM, ppm 50 MAX 20 - 50

TEST PROCEDURES

PROPERTY METHODS

CETANE NUMBER D 613

CETANE I NDEX D 4737

DENSI TY @ 15°C D4052

VI SCOSI TY @ 40°C D 445

SULPHUR, % WT D 2622 / 5453

LURI CITY D 6079

T 95, °C D 86

TEST PROCEDURESPROPERTY METHODS

FLASH POI NT, °C D 93

CARBON RESI DUE D 4530

CFPP I P 309

WATER CONTENT D 1744

OXI DATI ON STABI LI TY D 2274

ASH CONTENT D 482

COPPER CORRI SI ON D 130

TEST PROCEDURESPROPERTY METHODS

TOTAL AROMATI C D 5186

POLY AROMATI C D 2425

LOW TEMP. FLOW TEST D 4539

FOAM NF M 07 - 075

BI OLOGI CAL GROWTH NF M 07 - 070

TOTAL ACI D NUMBER D 974

I NJ ECTOR CLEANI NESS CEC / CUMMI NS L 10

CORRI SI ON PERFOR. D 665

TEST SIGNIFICANCE

• DENISTY - ESSENTIAL FOR QUNTITY CALCULATIONS, SETTING PURIFIER, INDICATES SPECIFIC ENERGY AND IGNITION QULAITY

• API GRAVITY ° = (141.5 / RELATIVE DENSITY @ 60 / 60°F) - 131.5

• FLASH POINT - LEGAL REQUIREMENT

• POUR POINT - FUEL MUST BE MAINTAINED ABOVE POUR POINT

TEST SIGNIFICANCE

• CARBON RESIDUE - HIGH VALUES MAY GIVE DEPOSIT PROBLEMS

• ASH - IF EXCESSIVE CAN GIVE FOULING DEPOSITS

• WATER - CAN CAUSE SLUDGE AND COMBUSTION PROBLEMS

• VANADIUM AND SODIUM - POTENTIAL HIGH TEMPERATURE CORROSION CAN BE MINIMISED BY TEMPERATURE CONTROL AND MATERIALS SELECTION

TEST SIGNIFICANCE

• ALUMINIUM AND SILICON - USUALLY PRESENT AS CATALYST FINES WHICH ARE ABRASIVE, CAN NORMALLY BE REDUCED TO AN ACCEPTABLE LEVEL BY A CENTRIFUGE

• SULPHUR

• SEDIMENT & STABILITY - FUEL IS STABLE IF IT DOES NOT BREAK DOWN GIVING HEAVY SEDIMENT

• COMPATIBILITY - THE ABILITY OF TWO FUELS WHEN MIXED TO REMAIN STABLE

TEST SIGNIFICANCE

• SPECIFIC ENERGY - NET VALUE FOR DIESEL AND GROSS VALUE FOR BOILERS, USUALLY CALCULATED FROM EMPIRICAL EQUATIONS

• IGNITION QULAITY - RELATES TO PART OF THE COMBUSTION PROCESS

– FOR RESIDUAL FUELS EMPIRICAL EQUATION FOR CCAI IS

– CCAI = d - 81-141 log log (VK + 0.85)

d = DENSITYVK = VISCOSITY

TEST SIGNIFICANCE

• VISCOSITY - DETERMINES INJECTION AND TRANSFER TEMPERATURES

FUEL INJ VISC INJ VISC 13 CST 17 CST

120 100 91160 112 104

170 115 107 180 119 109 200 121 111 220 123 113

COMPARISON OF FUELS

CHARACTERI STI C NAPHTHA HSD

FLASH POI NT, °C - 12 32

KI N VI SCOSI TY 0.55 3.55

TOTAL SED, mg/100ml NI L 5

GCV, cal/g 11400 10900

TOTAL SULPHUR 0.0048 0.25

DENSI TY, 15°C 0.72 0.84

VANADI UM, ppb 1 200

SODI UM, ppm 0.018 0.2

COMPARISON OF FUELS

CHARACTERI STI C NAPHTHA HSD

ACI DI TY I NORG NI L NI L

ACI DI TY TOTAL NI L NI L

ASH CONTENT, % WT NI L NI L

RCR, % WT NI L 0.034

CETANE NUMBER - 48

POUR POI NT, °C <- 54 6

CU STRI P CORROSI ON 1A 1A

RECOVERY @ 366°C - 97

CASE STUDY

• NAPHTHA

• DIESEL

• FUEL OIL

NAPHTHAFLUE GAS ANALYSI S A B

CARBON DI OXI DE 12.8 9.1

CARBON MONOXI DE 1.4 0

HYDROGEN 0.7 0

OXYGEN 2.1 7.4

HYDROCARBON 0.2 0

NI TROGEN 82.8 83.5

REACTIONS FOR BURNING

• CO + 1/2 O2 = CO2

• H2 + 1/2 O2 = H2O

• CnH n+x + (n+1)/2O2 = nCO2 + yH2O

EXCESS AIR NEEDED = (1.4+0.7+0.2)/2 = 1.15

SOOT CONTROL• FAULTY INJECTORS

– DEGREE OF ENRICHMENT– AIR REQUIREMENT– VOLUME OF COMBUSTION PRODUCTS– FLAME TEMPERATURE– ATOMISATION / OVERFUELING

• RESTRICTED AIR INTAKE

• EXCESSIVE EXHAUST BACK PRESSURE

• INTAKE AIR HOT

• LEAKAGE OF AIR THRU GASKETS

• PREIGNITION

• WRONG FUEL

ADDITIVES FOR HEAVY FUEL OILS

• CRUDE OILS AND FUEL OILS

• HEAVY FUEL OILS

• COMBUSTION MECHANISM

• POTENTIAL PROBLEMS AND SOLUTIONS

– ADDITIVE A & B

Viscosity,20°C

% asphaltenes

Gasoline (C5-80°)

Heavy gasoline (80-160°)

Kerosene (160-250°)

Middle distillate (250-300°)

Heavy distillate (300-400°)

Residue (400 +)

35.8

5.8

4.09

9.05

12.58

14.12

7.51

50.42

10.2

0.93

5.56

12.02

15.5

17.19

8.72

38.71

ARABIANHEAVY

ARABIANLIGHT

NIGERIANBONNY

11.2

0.08

5.06

15.0

9.32

25.2

44.6

FRACTIONS FROM 3 DIFFERENT CRUDES

CHARACTERISTICS OF SOME CRUDE OILS

Viscosity,20 °C,cSt

Sulfur,%

Vanadium, ppm

Nickel, ppm

Asphaltenes, %

Conradson carbon,%

Arabianlight

9.2

1.8

15

5

0.7

5.1

Arabianheavy

40

2.8

30

10

2.7

Ekofisk

10

0.12

< 1

1.4

0.88

Nigerialight

6.7

0.11

2

6

0.08

0.86

Basrahheavy

57

3.58

54

22

8.3

Boscan

250000

5.2

1200

100

10.8

16.4

Ural

12.5

1.8

65

20

2.7

Gas

AD

VD

Reforming

Visbreak.

Hydrocr.

Coking

FCC

DA

NaphtaGasolinesKeroseneDiesel oils

Heavy fuels SR1

2

3

Gasolines

GasolinesKero,Diesel

Heavy fuels

H2, no HeavyFuels

4

AsphaltsHeavy fuels

REFINERY SCHEMES

CHEMICAL COMPOSITION RESIDUE OR HEAVY FUEL OILRESIDUE OR HEAVY FUEL OIL

ASPHALTENESASPHALTENESMALTENESMALTENES

"OIL""OIL""RESINS""RESINS"

SATURATED SATURATED AROMATICAROMATIC

MODEL OF ASPHALTENE MOLECULE

S

CH2

CH3

CH2

CH3

CH3

CH

CH2

CH2

CH3

CH2CH2CH3

CH2CH2

S

S

CH2

CH2

CH3

CH2

S

CH

CH2

CH2

CH3

CH2

CH2

CH3

CH

CH2

CH2

CH3

CH2 CH2CH3

N

CH3

CH2

CH3

CH3

CH2

CH3

CH3

CH3

CH2CH2

O

CH2

S

CH2

CH2

CH2

CH

CH2

CH2

CH3CH3

CH2CH3

CH3

CH3

ASPHALTENES CHARACTERISTICS

• Polycondensed aromatic structures with few alkyl chains

• Contains hetero-atoms: S, N, O

• Contains metals: V, Ni, Na

• Not soluble in oil

• Size of the micellar unit: 8 - 20 A

• Cannot boil even under reduced pressure

• Molecular structure depends on crude oil origin

RESINS CHARACTERISTICS

• Chemical structure close to asphaltenes structure but:

• LONGER ALKYL CHAINS

• LESS CONDENSED RINGS

• MORE SOLUBLE IN OIL

• Molecular structure depends on crude oil origin

• Presence necessary to provide a good stability to the

fuel

HEAVY FUEL OILS

DISPERSED AND STABLE FLOCULATED

Resins ensure seperation of heavy asphaltene molecules. Flocculated Asphaltene molecules tend to form sludge and settle at the bottom of the tank.

COMBUSTION MECHANISM

Atomisation Vaporization

Combustion

Viscosity Distillate cuts

Distillate cutsDensityMetalsConradson Carbon

C/H Ratio

Ignition

SOOT

UNBURNT PARTICLES

FLAME FRONT

FUELDROPLET

CENOSPHERE

EMISSIONS OF PARTICLES

0.02 m

1 to 100 m

LIGHT GASEOUS FRACTIONS

Simple droplet combustion model

SOLID ACCUMULATION

CENOSPHERES

PARTICULATE EMISSIONS

• SOOT (Soot number from 0 to 9 Bacharach)

– GAS PHASE COMBUSTION

– OH* increases the rate of oxidation of soot precursors

• UNBURNT PARTICLES (mg/Nm3)

– HETEROGENEOUS COMBUSTION (CENOSPHERES)

2 H2O H2 + 2 OH*Catalyst M

CO + H2

Catalyst M ’Cenospheres + H 2 Ov

POTENTIAL PROBLEMS

• STORAGE STABILITY AND COMPATIBILITY

• UNBURNT PARTICLES

STORAGE• PROBLEMS

– ASPHALTENES PRECIPITATION – CLOGGING OF FILTERS AND PIPES– SATURATION OF SEPARATORS– CLOGGING OF INJECTION SYSTEM

• ORIGIN– ASPHALTENES PRECIPITATION

• BLEND OF NON-COMPATIBLE FUELS• STORAGE TEMPERATURE

• SOLUTION– ADDITIVES

ADDITIVE A

• Preventive action

• Curative action

Fuel without additive Fuel with additive A

ADDITVE A• DOSING RATE

– 1 LITRE FOR 2000 TO 5000 LITRES OF FUEL.

• IMPROVES HEAVY FUEL OIL STABILITY

• PREVENTS ASPHALTENE PRECIPITATION

• AVOIDS COMPATIBILITY PROBLEMS

• NON TOXIC PRODUCT

• NON TOXIC COMBUSTION PRODUCTS

UNBURNT PARTICLES• PROBLEM

– EMISSIONS OF UNBURNT PARTICLES– HEATING SURFACES FOULING– FREQUENT BOILER CLEANING– COST OF EMISSION LIMITATIONS

• ORIGIN– NEED OF COMBUSTION IMPROVER– VERY LOW METAL CONTENT

• SOLUTION– ADDITIVE B

EFFICIENCY OF ELF ADDITIVE B

AB

C

FUEL

12

1 : + ELF AC 13 S (1/3000 l)

2 : + ELF AC 13 S (1/2000 l)

Unburnt HC

mg/th

Excess of air%

400

300

200

100

10 200

ADDITIVE B• DOSING RATE:

– 1 LITRE FOR 2000 TO 4000 LITRES OF FUEL.

• REDUCES EMISSIONS OF UNBURNT PARTICLES – MORE THAN 50 %

• ALLOWS TO REDUCE EXCESS OF AIR.• REDUCES FOULING• ACHIEVES A MORE STABLE COMBUSTION YIELD.• REDUCES DEPOSITS ON HEAT TRANSFERS.• NON TOXIC PRODUCT• NON TOXIC COMBUSTION PRODUCTS

THANK YOU