FYP presentation

Hydrocracking Of Heavy Gas Oil

HYDROCRACKING OF HEAVY GAS OIL | Chemical Department | Batch 2010

GROUP MEMBERS OSAMA AHMED KHAN D-10-Ch-1294 NASEEM ZULFIQAR D-10-Ch-1222 SYED MOHSIN JAMAL D-10-Ch-1284 MUHAMMAD IRFAN D-10-Ch-1290 ABDUL REHMAN D-10-Ch-1238Advisor Mr. Engr. GhulamUllah Maitlo

Group no 08


Contents

Project Planning Introduction Process Flow Schemes Process Flow Diagram Material Balance Energy Balance Equipments Designing Equipments Costing


Project Planning



Introduction


Hydrocracking

Hydrocracking process implies severe cracking in the presence of hydrogen in order to obtain the low boiling range products.

Hydrogenation is a exothermic reaction while cracking is endothermic. Therefore, the overall reaction is Exothermic.


History

1st unit installed in Chevron, California Refinery in 1960.

It was used primarily to obtain high octane gasoline.

Early hydrocrackers used amorphous silica alumina catalysts.


Objectives

• It is used to convert high boiling feedstock molecules to smaller, lower boiling ones.

• Improves the percentage of low boiling substances.

• Convert low grade complex feedstock into more valuable low boiling products.

• Transform near solid residua to liquid fuels.


Feed-stocks & Products

Feed Products

Kerosene NaphthaStraight run diesel Naphtha/Jet fuel

Atmospheric gas oil Naphtha, Jet fuel, DieselVacuum gas oil Naphtha, Jet fuel, Diesel, lube oil

FCC LCO NaphthaFCC HCO Naphtha, Distillate

Coker LCGO Naphtha, DistillateCoker HCGO Naphtha, Distillate


Reactions

• Hydrodesulferization:

• Hydrodenitrogenation


Cracking Reactions


Catalyst

The hydrocracking of oil fractions is carried out on bifunctional catalysts consisting of a metal and an acid function.

The metal function serves for the hydrogenation/ dehydrogenation and the acid function is responsible for the isomerization and cracking reactions.

Pt-loaded zeolites are found to be the best catalyst and are predominantly used nowadays.


Process Flow

Schemes


Process Flow Schemes

1- Single Stage Once through


1- Single Stage Once through The feed mixes with hydrogen and goes to the

reactor. The effluent goes to fractionation, with the

unconverted material being taken out of the unit as unconverted material.

Conversion 60–70 %


2- Single Stage with Recycle


2- Single Stage with Recycle The feed mixes with hydrogen and goes to the

reactor. The unconverted feed is sent back to the

reactor section for further conversion. Conversion almost 100%


3- Double Stage with Recycle


3- Double Stage with Recycle Two reactors are used. The hydro-treating and some cracking takes

place in the first stage. Products from the first stage are sent to the

fractionator. The unconverted oil from the first stage is sent

to the second stage for further conversion.


ProcessFlow

Diagram


PFD at a glance


Material Balance


Stream # Temp. Pressure Flow rate HGO H2 Naphtha Kerosene Diesel C4

°F psig lb/hr mole%

1 150 175 422900 100 - - - - -

2 80 2290 17301 - 100 - - - -

3 150 422900 100 - - - - -

4 400 422900 100 - - - - -

5 330 889101 69 - 5 10 16 -

6 580 15 564191 100 - - - - -

7 589 2641 564191 100 - - - - -

8 680 2455 564191 100 - - - - -

9 750 2439 622804 4 96 - - - -

10 700 2415 622804 9 40 2 4.5 6.5 38

11 635 2360 622804 9 40 2 4.5 6.5 38

12 600 2350 622804 9 40 2 4.5 6.5 38

13 528 2345 622804 9 40 2 4.5 6.5 38

14 475 2340 622804 9 40 2 4.5 6.5 38

15 360 2330 622804 9 40 2 4.5 6.5 38

16 190 2310 622804 9 40 2 4.5 6.5 38

17 110 2300 622804 9 40 2 4.5 6.5 38

18 110 150 581492 15 - 3.5 7.5 11 63

19 105 150 560000 41 - 9 20 30 -

20 110 255 560000 41 - 9 20 30 -

21 230 225 560000 41 - 9 20 30 -

22 167 466201 41 - 9 20 30 -

23 190 15 29300 - - 100 - - -

24 379 15 122380 - - - 100 - -

25 485 15 173230 - - - - 100 -

26 106 2290 58613 - 100 - - - -

27 115 2520 58613 - 100 - - - -

28 405 2515 58613 - 100 - - - -

29 620 2505 58613 - 100 - - - -

30 750 2290 58613 - 100 - - - -

31 110 41312 - 100 - - - -

32 107 21492 - - - - - 100

33 330 93208 - - - - - 100

34 107 114700 - - - - - 100


Energy Balance


Reactor


Reactor

Conditions Inlet

Outlet Stream # 9 # 10

Temperature 750 F 700 F Pressure 2439 psig 2450 psig

∆H 75.63 MMBTU/hr -176.48 MMBTU/hr

∆Hrxn= ∆Hprd - ∆Hrea -252.107179 MMBTU/hr


Pre-Fractionator


Pre-Fractionator

Energy Balance Cooling water utilized in condenser = 3536 GPM

Condenser duty

= 28.3 MMBTU/HR Reboiler duty

= 51.5 MMBTU/HR

Inlet Enthalpy

= 54.18944 MMBTU/HR Total Outlet Enthalpies

= 60.73302 MMBTU/HR


Fractionator


Fractionator


Heat ExchangerE-1

Shell side:

Opr. Pressure 2470psig

Pressure drop 15psig

Tube side:

Opr. Pressure 2395psig

Pressure drop 15psig

Tube side:

total flow 622804lb/hr

liquid 123900lb/hr

vapor 498300lb/hr

heat duty= 38465700Btu/hr

Tube side sp. Heat= 0.950187Btu/lb.F


Heat ExchangerE-2

Shell side: 622804 lb/hrOpr. Pressure 2515 psig 52.27 APIPressure drop 10 psig 1 cpTube side: 635 FOpr. Pressure 2360 psig 0.95 btu/lb.F 620 FPressure drop 10 psig HCK effluent

Tube side:total flow 622804 lb/hrliquid 208000 lb/hr 600 F Rec. gasvapor 414200 lb/hr 58613 lb/hrheat duty= 20708233 btu/hr 1 cp

405 FShell side sp. Heat= 1.643276 btu/lb.F


Heat ExchangerE-3


Heat ExchangerE-4


Heat ExchangerE-5


Heat ExchangerE-6


Furnace

Inlet Stream

Temp 621 0F

Pressure 2505 psi

Flow rate 58640 lb/hr

Cp 3.50 btu/lb.F

Outlet Stream

Temp 750 0F

Pressure 2500 psi

Flow rate 58640 lb/hr

Cp 3.50 btu/lb.F

Over all heat balance Q = Qf + Qa - Qg - Qw

26184977.09 Btu/hr


Equipments Designing


Distillation Column

Theoretical stages 46

Real stages 79

Minimum reflux 7.4

Reflux 10

Feed point 23rd plate from bottom

Column diameter 2.5ft

Column length 40ft

Column volume 196.35ft3


Heat Exchanger

700

Outlet Temp.(°F) 635 Outlet Temp.(°F) 622000

45.71 Sp.heat(BTU/lb°F) 0.95 Sp.heat(BTU/lb°F)

1 0.77 0.072

38465700

37 8 1

Pressure drop (Psi) 11.54

Pressure drop (Psi)

680

SPECIFICATION SHEET

Type of heat exchanger Shell and tube heat exchanger

Fluid Data

Shell Side Tube Side

Reactor Effluent (Hot Fluid) Hydrogen bottom (Cold Fluid)

Inlet Temp.(°F) Inlet Temp.(°F) 589

0.75

Viscosity(cpoise) Viscosity(cpoise) 1

Flow rate (lb/hr) Flow rate (lb/hr) 563600

Density(lb/ft3) Density(lb/ft3) 62.27

Sp.gravity Sp.gravity 0.07 Thermal cond.(BTU/hr.ft°F) Thermal cond.(BTU/hr.ft°F) 0.178

Design Data

Shell side Tube side

Heat Duty (BTU/hr) Heat Duty (BTU/hr) 38465700

Number of tubes 268

2

Baffle Space Tube Length (ft) 16 Passes Tube OD (in) 1.5

R d ((hr)fft 2 )(°F)/BTU) 0.015

9.67

U c BTU/(hr)(ft2)(of) 22.65

U d (BTU/(hr)(ft2)(oF) 16.70

BWG 16 Pitch 17/8'' Triangular

Passes

Shell ID (in)


FurnaceFurnace Type Box

Heat Duty 26.45 MM Btu/hr

Initial Temperature 620 0F

Final Temperature 750 0F

Efficiency 75 %

FUEL DATA

Fuel Used Refinery Gases

L.H.V 19938.2 Btu/hr

Fuel Requirement 1769.02 lb/hr

Total Air Required 28114.9 lb/hr

Excess Air Used 20 %

Total Air Supply 33737.8 lb/hr

Air Fuel Ratio 19.07

RADIATION SECTION

Radiation Section Duty 24.4 Btu/hr

Avg Radiant Heat Flux 4000 btu/hr ft2

Overall Exchange Factor 0.63

Tube Surface Temperature 765 0F

Flue Gas Temperature 1200 0F

Tube Length 35.5 ft

Tube O.D 5 in

C-C Distance 8.5 in

No of Tubes 120

Tube Surface Area 3066.33 ft2

CONVECTION SECTION

Convection Section Duty 2.05 MM Btu/hr

LMTD 332 0F

Convective Co-efficient 5.8 btu/hr ft2

Area of Convection Section 1064.94 ft2

Tube Length 38.5 ft

Tube O.D 5 in

No of Tubes 67


SeparatorFluid Data

Vapor Mass Flow Rate (WV) 60000 lb/hr

Liquid Mass Flow Rate (WL) 562000 lb/hr

Vapor Density (ρV) 0.918 lb/ft3

Liquid Density (ρL) 45.55 lb/ft3

Conditions

Operating Pressure (P) 160 Bar

Operating Tempetrature 140 °F

Designing Data

Terminal Velocity (UT)0.488 ft/sec

Vapor Velocity (UV)4.9 ft/sec

Holdup Time (TH) 5 min

Holdup Volume (VH) 114 ft3

Vapor Disengagement Area Height (HV) 1 ft

L/D 5

Vessel Diameter (D) 3.078 ft

Vessel Length (L) 15.39 ft

Total Cross Sectional Area (A) 7.43 ft2

Low Liquid Level Height (HLLL) 0.75 ft

Low Liquid Level Area(ALLL) 1.39 ft2

High Liquid Level Height (HHLL) 2.078 ft


Pump

Pump Data

Type of Pump Centrifugal

No. of Stages Single

Single/Double Suction Single

Vertical/Horizontal Mounting Horizontal

Driver Type Electrical

Fluid Data

Fluid Pumped Mix HC

Specific Gravity (@ 60/60 0F) 0.733

0API 61.54

Density (Kg/m3) 733

Viscosity (cP) 0.5

Vapor pressure (Psig) 26.2

Working Temperature (0F) 110

Working Pressure (Psi) 150

Design Data

Design Capacity (gal/min) 25.46

Total Differential Head (ft) 100.78

Pump Efficiency (%) 33.23

NPSH Available (m) 198.25

Hydraulic Power (kw) 1.155

Work Done (KJ/Kg) 1.55

Work Done (Btu/lb) 0.6678


Compressor

Compressor Data

Type of Compressor Centrifugal

No. of Stages Single

Fluid Data

Fluid Compressed Hydrogen

Specific Gravity (@ 60/60 0F) 1.37

Viscosity (cP) 132.9

Suction Pressure (Psi) 2304.7

Discharge Pressure (Psi) 2534.7

Inlet Temperature (0F) 106

Outlet Temperature (0F) 115

Design Data

Work Done (Btu/lb) 10.068

Power (Hp) 232.3

Compressor Efficiency (%) 33.35


Equipments Costing

Cost Estimation

Equipment Approx. Cost ($)

Distillation Column 135000

Furnace 570000

Heat Exchanger 32000

Separator 6300

Pump 20000

Compressor 120000


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