GTL-Case nov 10 Lovraj Workshop-1

24/11/2010Slide Number- 1 of 38

Delivering excellence through people

GTL: A CASE STUDY FORGTL: A CASE STUDY FOR6000 BPD GTL PLANT6000 BPD GTL PLANT

R. N. MAITIR. N. MAITI, AJAY N. DESHPANDE, AJAY N. DESHPANDE

R&D DIVISIONR&D DIVISION

24 - 2524 - 25thth November, 2010 November, 2010

LOVRAJ KUMAR MEMORIAL TRUST ANNUAL WORKSHOPLOVRAJ KUMAR MEMORIAL TRUST ANNUAL WORKSHOP

NEW DELHINEW DELHI

GTL: A case study for 6000BPD GTL Plant24/11/2010

Slide Number - 2 of 38

Engineers India Ltd – Delivering excellence through people

OVERVIEWOVERVIEW

IntroductionIntroduction

Key technical components in GTL plant with FT routeKey technical components in GTL plant with FT route

Design Configuration of 6000 BPD GTL PlantDesign Configuration of 6000 BPD GTL Plant

Conversions & Thermal efficienciesConversions & Thermal efficiencies

Broad specifications of key equipmentsBroad specifications of key equipments

ConclusionsConclusions




GTL IN GAS ECONOMYGTL IN GAS ECONOMY




GTLGTL

GTL technology converts C1 fraction of natural gas to GTL technology converts C1 fraction of natural gas to hydrocarbon liquids hydrocarbon liquids

CH4 is chemically very stable components and requires CH4 is chemically very stable components and requires significant amount of energy and sophisticated catalyst systemssignificant amount of energy and sophisticated catalyst systems

GTL is residue free, sulphur freeGTL is residue free, sulphur free Products of GTLProducts of GTL

Naphtha; Diesel; High value Wax; High quality lube base Naphtha; Diesel; High value Wax; High quality lube base oilsoils

Not as substitute for piped natural gas/LNG/crudeNot as substitute for piped natural gas/LNG/crude

But as a unique feedstock for high quality fuels and lubesBut as a unique feedstock for high quality fuels and lubes




Basic Gas to Liquids Process

Base Oil / LubricantsSolvents ( n –parrafins)

Methane (+Ethane)

Ethane

Jet / Kerosene

Specialty Waxes

Optional Products

Sulfur

Synthetic

Crude

O2

NaphthaDiesel

GasProcessing

SynthesisGas

FischerTropsch

ProductRefining

AirSeparation

Utilities =Water, Steam & Power

Offsites =Flares, Controls, Bldgs.

Natural GasAir

LPGs – Propane/Butane

CO

H2

LPG

Condensate – C5+

Steam & Water

Steam




THREE STEP PROCESSTHREE STEP PROCESS

Syn Gas Generation: Steam Methane Reforming/partial Syn Gas Generation: Steam Methane Reforming/partial oxidation to produce syn gas (a mixture of hydrogen and CO oxidation to produce syn gas (a mixture of hydrogen and CO in the ratio of 2:1 molar)in the ratio of 2:1 molar)

Fischer Tropsch Synthesis: Syn gas synthesis to produce Fischer Tropsch Synthesis: Syn gas synthesis to produce liquid hydrocarbonsliquid hydrocarbons

Downstream processing (Tail gas treatment, Hydrocracking Downstream processing (Tail gas treatment, Hydrocracking of liquid products)of liquid products)




Step 1- Synthesis Gas GenerationStep 1- Synthesis Gas Generation

Synthesis Gas Generation- Steam Methane Reforming (SMR)- Partial Oxidation (POX)- Autothermal Reforming (ATR)

Natural Gas

SMR : CH4 + H2O

POX : CH4 + 1/2O2

Synthesis Gas

CO + 3H2, endothermic 206 kJ/mol

CO + 2H2, exothermic 38 kJ/mol

xH2 + yCO

Available Technology

800oCCatalytic

900-1400oCNon-catalyticATR : Same as POX but catalytic & uses air instead of oxygen




REACTIONS OCCURRING IN SYN GAS REACTORREACTIONS OCCURRING IN SYN GAS REACTOR

Reaction Mechanism

Reaction chemistry Hydrogen to CO ratio, Molar

Heat of Reaction, KJ/mol (20)

Steam Reforming CH4 + H2O CO + 3 H2 3 -206.1

Partial Oxidation 2CH4 + O2 2CO + 4 H2 2 38.0

Water Gas Shift reaction

CO + H2O CO2 + H2 - 41.15

CO2 Reforming CH4 + CO2 2CO + 2 H2 1 -247.3

Carbon Deposition CH4 2H2 + C -74.82Carbon Conversion C + H2O CO + H2 1 -131.3

Carbon Deposition 2CO CO2 + C - 173.3




SYN GAS REACTORSSYN GAS REACTORS

Processes Typical H2/CO ratio, molar

Oxygen Requirement

(Kg/Kg of NG)

Steam Methane Reforming (SMR)

>2.5 Nil

Partial Oxidation (POX) 1.5 - 2.0 1.0 - 1.2

Autothermal

(SMR + POX)

1.5 - 2.7 0.3 – 0.5




STEP 2 : F-T SYNTHESIS CONVERSIONSTEP 2 : F-T SYNTHESIS CONVERSION

F-T Reactor

Available Technology - Fixed bed - Fluidized bed (Circulating / Fixed) - Slurry bed

Synthesis Gas

Catalysts - Cobalt - Iron

CO hydrogenation nCO + 2nH2

Water gas shift CO + H2O

Methanation CO + 3H2

Syncrude (Long chain aliphatic HC,mainly n-paraffins)

(-CH2-)n + nH2O-152 kJ/molH2 + CO2 -41 kJ/molH2O + CH4 -206 kJ/mol

xH2+yCO (-CH2-)n

180-350oC20-35 bar




PRODUCT DISTRIBUTIONPRODUCT DISTRIBUTION

For further distribution of heavy cuts (CFor further distribution of heavy cuts (C55++) into gasoline ) into gasoline

(C(C5 5 - C- C1111), diesel (C), diesel (C11 11 - C- C1818), wax (C), wax (C1919++) Shultz-Flory ) Shultz-Flory

theory was used as given belowtheory was used as given below

Where WWhere Wr+r+ is weight of product with carbon number is weight of product with carbon number

greater than r-1, x = 5 and α is the probability of chain greater than r-1, x = 5 and α is the probability of chain growth.growth.




SALIENT FEATURES OF F-T SYNTHESIS SALIENT FEATURES OF F-T SYNTHESIS Composition is a function of chain growth mechanismComposition is a function of chain growth mechanism

Product is a mixture of light & heavy hydrocarbonsProduct is a mixture of light & heavy hydrocarbons

Composition depends on reaction temperature Composition depends on reaction temperature

-- 180-250 deg C : Predominantly diesel & waxes180-250 deg C : Predominantly diesel & waxes

-- 330-350 deg C : Predominantly gasoline & olefins330-350 deg C : Predominantly gasoline & olefins

Heat removal and control of temperature extremely critical. Heat Heat removal and control of temperature extremely critical. Heat typically recovered by boiling water in reactor tubes. typically recovered by boiling water in reactor tubes.




F-T CATALYSTS F-T CATALYSTS Focused on achieving highest chain growth (>0.95) Focused on achieving highest chain growth (>0.95)

towards heavy waxestowards heavy waxes Comprise of primary metal (Co or Fe), secondary metal Comprise of primary metal (Co or Fe), secondary metal

(Ru-Noble metal) & oxide promoter on alumina / silica (Ru-Noble metal) & oxide promoter on alumina / silica supportsupport

Co CatalystCo Catalyst Fe CatalystFe CatalystLifeLife Long Long Short Short

CostCost ExpensiveExpensive Low cost Low costSyngas H2/COSyngas H2/CO 2.0 2.0 0.7 to 2.0 0.7 to 2.0ProductsProducts Lower MW Lower MW High MW High MWBy productsBy products H2OH2O H2O/CO2 H2O/CO2




F-T REACTORSF-T REACTORS

Fixed Bed Reactor (FB)Fixed Bed Reactor (FB) Multitubular design with catalyst packed in tubesMultitubular design with catalyst packed in tubes Diameter limited by slow heat removalDiameter limited by slow heat removal Good for heavy liquid & waxesGood for heavy liquid & waxes

Fluidised Bed ReactorFluidised Bed Reactor Two typesTwo types : Circulating Fluidised Bed (CFB) : Circulating Fluidised Bed (CFB)

Fixed Fluidised Bed (FFB)Fixed Fluidised Bed (FFB) Improved heat removal by circulating gasImproved heat removal by circulating gas Suitable for gasoline ; Unsuitable for heavy waxesSuitable for gasoline ; Unsuitable for heavy waxes Reduced catalyst consumption in FFBReduced catalyst consumption in FFB

Slurry Reactor (MPSR)Slurry Reactor (MPSR) Very high heat transfer rateVery high heat transfer rate High conversion per pass avoids recycle costHigh conversion per pass avoids recycle cost Higher catalyst activity with better selectivity as no hot spotsHigher catalyst activity with better selectivity as no hot spots Catalyst regeneration by continuous purge and feedCatalyst regeneration by continuous purge and feed




STEP 3 : PRODUCT REFININGSTEP 3 : PRODUCT REFINING

ProductRefining

Long chain waxy HC Naphtha,Kero, Diesel,Waxes

(-CH2-)n

• Hydroprocessing Section - Hydroisomerisation / hydrocracking of n-paraffins to iso-paraffins of

desired length & boiling range- Mild hydrocracking at 300-350 deg C & 30-50 bar- Reactivity increases with increasing number of paraffins - Maximum yield of middle distillates

- Minimum yield of C4 & lighters• Distillation Section

Conventional distillation for product fractionation• Gas Processing & Wax Finishing as necessary




TAIL GASTAIL GAS

Efficient utilization of tail gas is must to improve economicsEfficient utilization of tail gas is must to improve economics

Fuel Gas CombustionFuel Gas Combustion

LPG Recovery followed by Gas CombustionLPG Recovery followed by Gas Combustion

CO2 recovery followed by gas combustionCO2 recovery followed by gas combustion

CO2 recovery followed by adsorption for H2CO2 recovery followed by adsorption for H2




GTL Block Flow DiagramGTL Block Flow Diagram

Tail gas

GTL ProductsSMR+ATR

Air sep unit

NG feed

CO2 Recycle

O2

Steam GenerationExport Steam

H2

N2

CO2

Amine treating

FT synthesis

Water treatment




CONCEPT STUDIESCONCEPT STUDIES

BASISBASIS

Tripura Gas composition is taken as the basisTripura Gas composition is taken as the basis

SMR+ATR simulations were carried out using SMR+ATR simulations were carried out using

FEM of Gibbs Energy algorithm in Aspen PLUSFEM of Gibbs Energy algorithm in Aspen PLUS

Fixed bed FT reactor ( Reactor Model; in-house)Fixed bed FT reactor ( Reactor Model; in-house)

Utilization of tail gas Utilization of tail gas




GAS COMPOSITIONSGAS COMPOSITIONS

Composition Mol% H2

CH4 97.53C2H6 1.97C3H8 0.12

C4H10 0.02N2 0O2 0CO 0

CO2 0.36H2O 0CO2 0




SYN GAS GENERATIONSYN GAS GENERATION

FEM studies (using ASPEN RGIBBS reactor module) show that FEM studies (using ASPEN RGIBBS reactor module) show that POX, Steam Reforming, and ATR reactors operate close to POX, Steam Reforming, and ATR reactors operate close to thermodynamic equilibrium.thermodynamic equilibrium.

The model is used to determine steam and oxygen feed rates, and The model is used to determine steam and oxygen feed rates, and operating temperature and pressure required for obtaining syngas operating temperature and pressure required for obtaining syngas of required composition.of required composition.

Part of the Natural gas is reformed at high steam to carbon ratio Part of the Natural gas is reformed at high steam to carbon ratio with heat derived from hot syn gas from POXwith heat derived from hot syn gas from POX

Partially reformed syn gas along with balance natural gas and Partially reformed syn gas along with balance natural gas and oxygen is oxidised in second reactor at substoichiometric conditionoxygen is oxidised in second reactor at substoichiometric condition

Syn gas from second reactor provides heat for reforming in first Syn gas from second reactor provides heat for reforming in first reactorreactor




FT REACTORFT REACTOR

Multi tubular fixed bed reactor modelMulti tubular fixed bed reactor model Kinetics based on FE catalystKinetics based on FE catalyst Once through typeOnce through type Intermittent removal of WaterIntermittent removal of Water Optimum Tube diameter for better heat Optimum Tube diameter for better heat

removalremoval




FLOW SCHEMEFLOW SCHEME




FLOW SCHEMEFLOW SCHEME




OVERALL MATERIAL BALANCEOVERALL MATERIAL BALANCE

H/C 1046 TPD

Water 1394 TPD

SMR +ATR

ASU/PSA

PSA

Three Phase Flash

NG 1947 TPD(1612+336)

SG 7452 TPD

CO2 Recyl 840 TPD

O2 (95%) 362 TPD

Power Plant

Amine

Treating

CO2 Purge450 TPD

FT I/II/III

TG454 TPD

Water3071TPD

H2191 TPD

Steam 4639 TPD




CONVERSIONSCONVERSIONS

Conversion calculations

NG Feed Basis

Feed 67155 Kg/h

Product 43583 Kg/h

Conversion 64.9 %

Total NG Basis

NG to Feed 67155 Kg/h

NG to fuel header 13981 Kg/h

Product 43583 Kg/h

Conversion 53.7 %




OVER ALL ENTHALPY BALANCEOVER ALL ENTHALPY BALANCE

Overall Enthalpy Balance

Feed Q, mmkcal/hTo Unit 725To SMR 151

ProductsH/C Liquid 436Hydrogen 228Tail gas 111Loss with Flue Gas 38Loss with Syn gas Cooler 45 Thermal Conversion 60.1%




OVERALL GTL CHEMISTRYOVERALL GTL CHEMISTRY

(12+x) CH4 + (5.5 +2 x) O2 (12+x) CH4 + (5.5 +2 x) O2

n C12 H26 + (11+2x) H2O + x CO2n C12 H26 + (11+2x) H2O + x CO2

With x = 0With x = 0 Max theoretical energy efficiency : 78%Max theoretical energy efficiency : 78% Carbon conversion efficiency : 100%Carbon conversion efficiency : 100%

With x = 2.4 - 3.6With x = 2.4 - 3.6 Thermal efficiency up to 60-65%Thermal efficiency up to 60-65% Carbon conversion efficiency up to 77-83 %Carbon conversion efficiency up to 77-83 %




CARBON BALANCE THROUGH CARBON BALANCE THROUGH REACTORSREACTORS

Carbon Balance

Feed 4183 kmol/h

Product

Liquid Products 3072 kmol/h

Tail Gas 682 kmol/h

CO2 vent 427 kmol/h

Total 4180




CARBON DISTRIBUTIONCARBON DISTRIBUTION

H/C 73.5

Water

SMR +ATR

ASU/PSA

PSA

Three Phase Flash

NG 120

SG100

CO2 Recyl

O2 (95%)

Power Plant

Amine

Treating

CO2 Purge10.2

FT I/II/III

TG16.3

Water

H2

Steam




ENTHALPYENTHALPY

H/C 60.1

Water

SMR +ATR

ASU/PSA

PSA

Three Phase Flash

NG 100+20

SG

CO2 Recyl

O2 (95%)

Power Plant

Amine

Treating

CO2 Purge

FT I/II/III

TG

Water

H231.5

Steam




UTILITY: HP STEAM DRIVEN COMPRESSORSUTILITY: HP STEAM DRIVEN COMPRESSORS

Compressors

K-01 ng compressor 2109 KW

K-02syn gas compressor 17900 KW

K-03 O2 compressor 1160 KW

K-04 CO2 compressor 4240 KW

K-05 air compressor 660 KW




UTILITIES: STEAM GENERATION/CONSUMPTIONUTILITIES: STEAM GENERATION/CONSUMPTION

HP Steam Consumption Press (Kg/cm2.g)

Temp (Deg C)

Reformer193276 kg/hr 42 258

Compressors K-01 to K-05192056 kg/hr 42 450

Excess Steam for power generation 97944 kg/hr 42 450

MP steam Amine Absorber

FT Feed Heaters

Generation

HP Steam Flue Gas + ATR o/I200000 kg/hr 42 258

Flue Gas + ATR o/I290000 kg/hr 42 450




BROAD SPECIFICATION OF FT REACTORSBROAD SPECIFICATION OF FT REACTORS

FT Reactors

40 mm ID tube, 12 m

R-04 A/B/C

FT Reactor-1 63 MMKcal/h, 12000 tubes, 4000 tubes/reactor

R-5 A/B FT Reactor-231 MMKcal/h, 5800 tubes, 2900/reactor

R-06 FT Reactor-317 MMKcal/h, 4000 tubes




BROAD SPECIFICATION OF COMPRESSORSBROAD SPECIFICATION OF COMPRESSORS

Power, KW Turbine type

HP steam driven (steam @ 42 kg/cm2 g, 450 deg C)

K-01 NG compressor 2109 Back Press

K-02 syn gas compressor 17900 Condensing

K-03 O2 compressor 1160 Back Press

K-04 CO2 compressor 4240 Back Press

K-05 Air compressor 6600 Back Press




BROAD SPECIFICATION OF EXCHANGERSBROAD SPECIFICATION OF EXCHANGERS

Exchangers Q, mmKcal/h

E-01 RG Boiler 147

E-02 Economiser 45

E-03A DM water Heater 24

E-03B Syn gas Cooler 54

E-04 Feed to Reactor FT-1 10.57

E-05 FT-1 o/I and syn gas exchanger 4.45

E-06 FT-1 product cooler 25.6

E-07 FT-2 feed heater 4.42

E-08 FT-2 O/I and syn gas exchanger 3.16

E-09 FT-2 Product cooler 13.6

E-10 FT-3 feed heater 3.02

E-11 FT-3 product cooler 10.5




CONCLUSIONSCONCLUSIONS

The various technical components of GTL plant through The various technical components of GTL plant through FT route for natural gas utilization are presentedFT route for natural gas utilization are presented

Conceptual design configuration of 6000 BPD GTL plant Conceptual design configuration of 6000 BPD GTL plant providedprovided

Recycle of CO2 and utilization of Tail gas scheme Recycle of CO2 and utilization of Tail gas scheme incorporated for better economyincorporated for better economy

Mass conversion is found to be 64.9%Mass conversion is found to be 64.9% Thermal conversion was found to be 60.1% for H/C liquids Thermal conversion was found to be 60.1% for H/C liquids

and 75.8% considering H2 productionand 75.8% considering H2 production




CONCLUSIONSCONCLUSIONS

HP steam(@450 0C, 42 ata) and excess H2 is for export or HP steam(@450 0C, 42 ata) and excess H2 is for export or integration with refinery.integration with refinery.

GTL is very expensive process. An attempt is made to provide GTL is very expensive process. An attempt is made to provide the Facts and Figures of a semi-commercial size GTL plant. the Facts and Figures of a semi-commercial size GTL plant.

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Economics for a 7100 BPD GTL Plant at NumaligarhEconomics for a 7100 BPD GTL Plant at Numaligarh

Case Natural Gas @ Rs 0.6/SCM*

Natural Gas @ Rs 1.7/SCM

Natural Gas @ Rs 3.0/SCM

Installed Cost 350 350 350

Annual Expenditure

Feed Stock 13.2 37.5 66.2

Others 15.9 19.8 24.3

Annual Revenue 131.2 131.2 131.2

Internal Rate of Return, % 23 17 8

In Million US Dollars* ~ 0.5 US $/Million BTU




Product distributionProduct distribution

C5-12=28%C5-12=28%

C13-18=22.6%C13-18=22.6%

C18+=49.6%C18+=49.6%










Free Energy Minimization StudiesFree Energy Minimization Studies

ASPEN Plus RGIBBS reactor model usedASPEN Plus RGIBBS reactor model used Chemical and phase equilibrium composition can be Chemical and phase equilibrium composition can be

calculated calculated Approach used is Gibbs free energy minimization Approach used is Gibbs free energy minimization

(FEM) of the system subject to atom balance (FEM) of the system subject to atom balance constraints constraints

Reaction stoichiometry need not be specifiedReaction stoichiometry need not be specified However, with reaction stoichiometry defined, approach However, with reaction stoichiometry defined, approach

to equilibrium can be specifiedto equilibrium can be specified




Conclusions from FEM StudiesConclusions from FEM Studies POX, Steam Reforming, and ATR reactors operate POX, Steam Reforming, and ATR reactors operate

close to thermodynamic equilibriumclose to thermodynamic equilibrium.. ASPEN RGIBBS reactor module can be used for ASPEN RGIBBS reactor module can be used for

predicting the equilibrium outlet composition for predicting the equilibrium outlet composition for SMR, POX and ATR.SMR, POX and ATR.

The model can be used to determine steam and The model can be used to determine steam and oxygen feed rates, and operating temperature and oxygen feed rates, and operating temperature and pressure required for obtaining syngas of required pressure required for obtaining syngas of required composition.composition.

Design of individual systems such as burner, Design of individual systems such as burner, reactor size, feed distributor, catalyst bed etc is to reactor size, feed distributor, catalyst bed etc is to be decided by specialized groupbe decided by specialized group




SYN gas generationSYN gas generation

ASPEN RGIBBS reactor module can be used for ASPEN RGIBBS reactor module can be used for predicting the equilibrium outlet composition for SMR, predicting the equilibrium outlet composition for SMR, POX and ATRPOX and ATR

POX, Steam Reforming, and ATR reactors operate POX, Steam Reforming, and ATR reactors operate close close to thermodynamic equilibriumto thermodynamic equilibrium..

Part of the Natural gas is reformed at high steam to Part of the Natural gas is reformed at high steam to carbon ratio with heat derived from hot syn gas from POXcarbon ratio with heat derived from hot syn gas from POX

Partially reformed syn gas along with balance natural gas Partially reformed syn gas along with balance natural gas and oxygen is oxidised in second reactor at and oxygen is oxidised in second reactor at substoichiometric conditionsubstoichiometric condition

Syn gas from second reactor provides heat for reforming Syn gas from second reactor provides heat for reforming in first reactorin first reactor




Studies with actual caseStudies with actual case

Part of the Natural gas is reformed at high steam to Part of the Natural gas is reformed at high steam to carbon ratio with heat derived from hot syn gas from carbon ratio with heat derived from hot syn gas from POXPOX

Partially reformed syn gas along with balance natural Partially reformed syn gas along with balance natural gas and oxygen is oxidised in second reactor at gas and oxygen is oxidised in second reactor at substoichiometric conditionsubstoichiometric condition

Syn gas from second reactor provides heat for Syn gas from second reactor provides heat for reforming in first reactorreforming in first reactor




Methane Autothermal reformingMethane Autothermal reforming




Performance IndicesPerformance Indices

Conversion (H2+CO):-Conversion (H2+CO):- 94%94% Conversion H2:-Conversion H2:- 96.1%96.1% Conversion CO:-Conversion CO:- 89.9%89.9%

C5+ g/NM3 of (H2+CO) converted:- 190C5+ g/NM3 of (H2+CO) converted:- 190 C5+ conversion based on NG= 61%C5+ conversion based on NG= 61% Recycle compressor eliminated for FT reactorRecycle compressor eliminated for FT reactor




Procedure Validation (POX)Procedure Validation (POX)

Simulation of Shell Gasification Process (SGP) Data for Natural Gas Feedstock

Parameter Case-1 Case-2 Case-3

Steam/C 0.176 0.176 0.655

O2/C 0.638 0.642 0.684

CO2/C 0.35 Nil Nil

Shell Aspen Shell Aspen Shell Aspen

H2/CO

H2 mol% dry

CO “

CO2 “

CH4 “

1.6

57.46

35.83

5.45

1.0

1.64

58.8

35.8

4.6

0.64

1.83

61.88

33.75

3.1

1.0

1.93

63.6

33.0

2.8

0.4

2.0

61.71

30.85

6.16

1.0

2.17

63.7

29.4

6.28

0.37




Procedure Validation (Primary/Secondary Procedure Validation (Primary/Secondary Reformer)Reformer)

Parameter Case1(P=9.5bar) Case2 (P=16.0bar) Case3 (POX)

Steam/C 2.226 4.0 Nil

O2/C 0.2923 0.239 0.665

Kellogg Aspen Kellogg Aspen Texaco Aspen

% Conv 99.12 99.73 99.04 99.75 >99.9 >99.9

H2/CO 3.564 3.57 4.86 4.72 1.745 1.659




Procedure Validation (ATR)Procedure Validation (ATR)

Simulation of Haldor Topsoe (HT) Data

Parameter Case-A Case-B Case-C Case-D

Steam/C 0.6 0.36 0.21 0.51

O2/C 0.58 0.57 0.59 0.62

CO2/C 0.01 0.01 0.01 0.19

HT Aspen HT Aspen HT Aspen HT Aspen

Temp, C 1000 1020 1021 1022 1065 1100 1031 1025

H2/CO

H2+CO*

CH4+CO2*

2.34 2.3 2.16

93.4

6.5

2.15

93.6

6.2

2.02

95.7

4.2

1.96

95.4

4.4

1.83

91.3

8.6

1.8

91.5

8.3

* Mol % dry




REACTOR MODEL: FT ReactionREACTOR MODEL: FT Reaction

molkJH

OHCHOHCO

R /152298

120

222

molkJH

HCOOHCO

R /41298

30

222

molkJH

OHCHHCO

R /206298

230

242




REACTOR MODEL: Rate equationREACTOR MODEL: Rate equation

OHSoHSSCO

HMoHMMCO

HFToFTCO

SCOMCOFTCOiCOmn

cekcTkr

cekcTkr

cekr

rrrr

RTMAE

RTMAE

COcOHc

RTFTAE

cat

CO

2,2,

2,2,

6.11

12,,

,,,,

,

,

2

,

conversion CO of rate Total




REACTOR MODEL: Mass, Momentum and energy REACTOR MODEL: Mass, Momentum and energy balancebalance

40

COforequationContinuty

, zru iCOBZC

SCO

50

equation BalanceEnergy 4

,

coolDU

RiCOBZT

ptS TTHizrCCu

mht

DoDi

hohiU 111

where

75.1

6

equationbalance Momentum

Re150

100133.11

2

163

2

p

pf

p

p

r

Gf

ZP

f




Process Integration IssuesProcess Integration Issues

Large energy streams for syn gas generation and syn Large energy streams for syn gas generation and syn gas synthesisgas synthesis

The process can be configured to maximize on The process can be configured to maximize on power/hydrogen/Steam for exportpower/hydrogen/Steam for export

Efficient utilisation of tail gas is must to improve Efficient utilisation of tail gas is must to improve economicseconomics Four options were studiedFour options were studied




Utilisation of Fuel GasUtilisation of Fuel Gas(Option-1 Fuel Gas Combustion)(Option-1 Fuel Gas Combustion)

Gas Combustion

Power/Steam

CO2 to vent

Fuel Gas 2407 TPD

Air

CO2 2560 TPD

•Gas to combustion has very low calorific value (1930 Kcal/kg)

•May require a support fuel

CO 169 TPD

CO2 1923

H2 89

N2 74

H/C 144

H2O 8




Utilisation of Fuel GasUtilisation of Fuel Gas(Option-II LPG Recovery followed by Gas Combustion)(Option-II LPG Recovery followed by Gas Combustion)

LPG Recovery

LPG 78 TPD

Gas Combustion

Power/Steam

CO2 to vent

Fuel Gas 2407 TPD

Air

CO2 2200 TPD

CO 6% Mol

CO2 43.6%

H2 44.4%

N2 2.6%

H/C 2.9%

H2O 0.5%

•Gas to combustion has very low calorific value (1600 Kcal/kg) may require a support fuel

•Additional recovery of LPG

CO 169 TPD

CO2 1923

H2 89

N2 74

H/C 144

H2O 8




Utilisation of Fuel GasUtilisation of Fuel Gas(Option-III CO2 recovery followed by gas (Option-III CO2 recovery followed by gas

combustion)combustion)

CO2 Recovery by DEA

CO2 1923 TPD

Gas Combustion

Power/Steam

CO2

Fuel Gas 2407 TPD

Air

CO 9.8% Mol

H2 72.6%

N2 4.3%

H/C 12.6%

H2O 0.7%

•Gas to combustion has high calorific value (9600 Kcal/kg)

•Size of gas turbine is drastically reduced




Utilisation of Fuel GasUtilisation of Fuel Gas(Option-IV CO2 recovery followed by Adsorption)(Option-IV CO2 recovery followed by Adsorption)

CO2 Recovery

CO2 1923 TPD to vent

Low Pressure Gas to CO boiler/ Flare

Fuel Gas 2407 TPD

CO 9.8% Mol

H2 72.6%

N2 4.3%

H/C 12.6%

H2O 0.7%•Additional hydrogen is recovered; reduces steam injection to POX

•CO2 vented out separately

PSA

H2 to Export




EIL NEW DELHI INDIA

Partial OxidationPartial Oxidation

•CH4 + 1/2 O2 CO + 2 H2

•Combustion chamber at high temperature (1200- 1500°C); no catalyst

•Three process sections:

• Burner section where combustion occurs (with oxygen to avoid presence of nitrogen—nitrogen is desirable only when making ammonia)

• Heat recovery section

• Carbon black removal section: first by water scrubbing, Then, extraction by naphtha from the sludge




EIL NEW DELHI INDIA

Steam Methane ReformingSteam Methane Reforming CH4 + H2O CH4 + H2O CO + 3 H2 CO + 3 H2 Carried out in the presence of catalyst—usually nickel Carried out in the presence of catalyst—usually nickel

dispersed ondispersed onalumina supportalumina support

Operating conditions: 850 - 940°C, 30 Kg/cm2Operating conditions: 850 - 940°C, 30 Kg/cm2 Tubular, packed reactors with heat recovery from flue Tubular, packed reactors with heat recovery from flue

gases using feed preheating or steam production in gases using feed preheating or steam production in waste heat boilerswaste heat boilers

Combination of steam reforming with partial oxidationCombination of steam reforming with partial oxidation—uses the heat produced from partial oxidation to —uses the heat produced from partial oxidation to provide heat for steam reforming; resulting provide heat for steam reforming; resulting combination is autothermalcombination is autothermal– Gases from partial oxidation burner are mixed with – Gases from partial oxidation burner are mixed with steam and sent to the steam reformersteam and sent to the steam reformer

Documents

GTL-Case nov 10 Lovraj Workshop-1