Refinery Operations Planning Sarah Kuper Sarah Shobe Andy Hill - - PowerPoint PPT Presentation

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Refinery Operations Planning Sarah Kuper Sarah Shobe Andy Hill - - PowerPoint PPT Presentation

Refinery Operations Planning Sarah Kuper Sarah Shobe Andy Hill Refinery Operations Planning What is a refinery? Takes crude oil and converts it into gasoline Distills crude into light, medium, and heavy fractions Lightest


slide-1
SLIDE 1

Refinery Operations Planning

Sarah Kuper Sarah Shobe Andy Hill

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SLIDE 2

Refinery Operations Planning

  • What is a refinery?

– Takes crude oil and converts it into gasoline – Distills crude into light, medium, and heavy fractions

  • Lightest fractions – gasoline, liquid petroleum gas
  • Medium fractions – kerosene and diesel oil
  • Heavy fractions – gas oils and residuum
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SLIDE 3
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SLIDE 4
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SLIDE 5

Process that is fed by heavier fractions to produce lighter fractions

Hydrocracker Reformer

Process used to increase the octane number of light crude fractions

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SLIDE 6

Distillation Column

Process that separates crude oil into fractions according to their boiling point

Gasoline Blending

Process that blends various streams of gasoline

Delayed Coking

Process used to produce high value liquid products

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SLIDE 7

Hydrotreating

Process that uses H2 to break up sulfur, nitrogen compounds, and aromatics

Isomerization

Process that converts normal, straight chain paraffins to iso- paraffins

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SLIDE 8

Refinery Operations Planning

“Refining is a complex

  • peration that depends

upon the human skills of

  • perators, engineers, and

planners in combination with cutting edge technology to produce the products that meet the demands of an intensely competitive market.”

Sources: http://www.exxon.mobil.com/UK-English/Operations/UK_OP_Ref_RefOp.asp and http://static.flickr.com/18/24007819_4d67ab2c0b.jpg

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SLIDE 9

Refinery Operations Planning

  • Planning groups in a refinery attempt to
  • ptimize the refinery’s profits by

purchasing specific amounts of different crudes

  • Based on:

– Projected market demands and prices – Unit capabilities – Planned turnarounds

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SLIDE 10

HDS FOVS FO2 GASOLINE POOL DIESEL POOL CDU2 CDU3 MB

FG LPG Naphtha FO Kero DO

NPU

LN HN

ISOU CRU

HN FG REF LPG

KTU

ISO LN Kero IHSD

MTBET DCCT ISOG SUPG HSD JP1 FO1

Products Intermediates

PHET SLEB LB TP OM

Crudes Kero FO Kero

Refinery Operations Planning

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SLIDE 11

Refinery Operations Planning

  • Planning Example

– Winter

  • high fuel oil demand → more fuel (heating) oil produced

– Summer

  • lower fuel oil demand → more gasoline produced
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SLIDE 12

Refinery Operations Planning

  • LP models use

average operating conditions

  • Graph shows that

average operating conditions may not

  • ptimize particular

unit (CRU)

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SLIDE 13

Current Models

  • Current models operate linearly (LP)

– Black Box Theory

  • PIMS (by Aspentech)
  • RPMS (by Honeywell Hi-Spec Solutions)
  • GRMPTS (by Haverly)
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SLIDE 14

HDS FOVS FO2 GASOLINE POOL DIESEL POOL CDU2 CDU3 MB

FG LPG Naphtha FO Kero DO

NPU

LN HN

ISOU CRU

HN FG REF LPG

KTU

ISO LN Kero IHSD

MTBET DCCT ISOG SUPG HSD JP1 FO1

Products Intermediates

PHET SLEB LB TP OM

Crudes Kero FO Kero

Black Box Theory

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SLIDE 15

LP Planning

  • ut

i

F ,

in

F

conversion %

  • ut

ON 98 =

  • ut

ON

in

  • ut

j

F F ⋅ = 25 .

,

  • ut

j

F ,

in

  • ut

i

F F ⋅ = 75 .

,

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SLIDE 16

HDS FOVS FO2 GASOLINE POOL DIESEL POOL CDU2 CDU3 MB

FG LPG Naphtha FO Kero DO

NPU

LN HN

ISOU CRU

HN FG REF LPG

KTU

ISO LN Kero IHSD

MTBET DCCT ISOG SUPG HSD JP1 FO1

Products Intermediates

PHET SLEB LB TP OM

Crudes Kero FO Kero

Modeling Unit Operations

  • Temperature

Pressure FlowRate InputSulfur WeightPercent

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SLIDE 17

Modeling Unit Operations

  • Temperature

Pressure FlowRate InputSulfur WeightPercent

) , , (

,

F P T f F

  • ut

S

=

in

F

  • ut

HC

F

,

[ ]out

S

  • ut

S

F ,

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SLIDE 18

General Goal

  • To effectively model a refinery’s unit
  • perations in the overall planning model.
  • Bangchak refinery in Thailand is used as a

case study.

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SLIDE 19

More Specific Goals

  • Model Hydrotreaters
  • Model Catalytic Reformers
  • Model Isomerization
  • Tie Unit Operations to GRM

– Add Operating Costs

  • Tie Unit Operations to blending

– Calculate blending properties

  • Integrate Fuel Gas system
  • Create Hydrogen balance
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SLIDE 20

Original LP Model

  • LP model developed

– Operates using Black Box theory

  • Optimizes purchased crudes and additives
  • Evaluates uncertainty and risk
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SLIDE 21

Bangchak Refinery

HDS FOVS FO2 GASOLINE POOL DIESEL POOL CDU2 CDU3 MB

FG LPG Naphtha FO Kero DO

NPU

LN HN

ISOU CRU

HN FG REF LPG

KTU

ISO LN Kero IHSD

MTBET DCCT ISOG SUPG HSD JP1 FO1

Products Intermediates

PHET SLEB LB TP OM

Crudes Kero FO Kero

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SLIDE 22

Bangchak Refinery

  • Hydrotreating

– NPU2 – NPU3 – HDS – KTU

  • Catalytic Reforming

– CRU2 – CRU3

  • Isomerization

– ISOU

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SLIDE 23

Bangchak Model

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SLIDE 24

Hydrotreating

  • The purpose of hydrotreating

is to remove undesired impurities from the stream

– Sulfur – Nitrogen – Basic Nitrogen – Aromatics

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SLIDE 25

Hydrotreating Reactions

  • Most common

non-hydrocarbon by-products:

– H2S – NH3

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SLIDE 26

Hydrotreating PFD

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SLIDE 27

Hydrotreating Model

  • Langmuir-Hinshelwood kinetic rate law
  • Main operating variables

– Temperature (600-800° C) – Pressure (100-3000 psig) – H2/HC ratio (2000 ft3/bbl) – Space Velocity (1.5-9.0)

  • Based on Flow Rate and Volume
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SLIDE 28

Langmuir-Hinshelwood

( ) 

       ⋅ + ⋅ ⋅ − =

2 45 .

2 2 2

1

S H S H H S

C K C C k r

Where, k = rate constant KH2S = adsorption equilibrium constant A = Arrhenius constant E = activation energy

T R E

e A k

⋅ −

⋅ =

T R S H

e K

⋅ =

2761

84 . 41769

2

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SLIDE 29

HDS Inputs

  • Variables

– Temperature – Pressure – Flow Rate

  • Data

– Sulfur weight percent* – H2/HC ratio (2000 ft3/bbl) – Sizing constant (1.8E8)

*Sulfur weight percent is set as a constant due to small effect on percent conversion and specifying too many variables in the overall model causes non-convergence

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SLIDE 30

Excel Model

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SLIDE 31

GAMS Model

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SLIDE 32

Catalytic Reforming

  • Process used to increase the octane

number of light crude fractions

  • Converts low-octane naptha into high-
  • ctane aromatics
  • High octane product is useful for creating

premium gasolines

  • Hydrogen is the by-product
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SLIDE 33

Catalytic Reforming Process Flow Diagram

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SLIDE 34

Catalytic Reforming Unit Operating Conditions

  • Low pressures (30- 40atm)
  • High Temperatures (900- 950 ºF)
  • Feedstock

– Heavy naphtha from hydrotreating unit

  • Catalyst

– Platinum bi-function catalyst on Alumina support

  • Continuous process

– Catalyst is removed, replaced, and regenerated continuously and online

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SLIDE 35

Catalytic Reforming Model

  • Model Purpose

– Predict the output of system through simplified inputs – Optimal Operating Parameters = Maximum Yield and Profit

  • Model Method

– Differential equations with changeable input parameters

  • Model Challenges

– Complicated components (pseudo) – Extreme operating conditions – Complicated reactions

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SLIDE 36

Catalytic Reforming Model

  • Input Parameters

– Temperature – Pressure – Volumetric Flowrates – Component Composition (Mole %)

  • Napthenes
  • Paraffins
  • Aromatics
  • Output Parameters

– Reformate – Hydrogen – Liquefied Petroleum Gas

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SLIDE 37

Catalytic Reforming Components

  • Paraffins

– Straight chain hydrocarbons – Highest H:C ratio

  • Napthenes

– Cyclic hydrocarbons – Medium H:C ratio

  • Aromatics

– Cyclic hydrocarbons – Lowest H:C ratio

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SLIDE 38

Catalytic Reforming Reactions

  • Dehydrogenation
  • Isomerization
  • Aromatization
  • Hydrocracking
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SLIDE 39

Catalytic Reforming Model

  • Simplified Reactions and Equations from Smith

(1959)

  • Modeled Reactions

– Dehydrogenation, Cyclization, Aromatization, and Hydrocracking

( ) ( ) ( ) ( )

napthenes

  • f

ing Hydrocrack paraffins

  • f

ing Hydrocrack H napthenes Paraffins H aromatics Napthenes _ _ 4 _ _ 3 2 * 3 1

2 2

+ → ← + → ←

slide-40
SLIDE 40

Catalytic Reforming Stoichiometry

( )

5 4 3 2 1 2 2

15 15 15 15 15 3 4 C n C n C n C n C n H n H C

n n

+ + + + →  +

( )

5 4 3 2 1 2 2 2

15 15 15 15 15 3 3 3 C n C n C n C n C n H n H C

n n

+ + + + →        − +

+

( )

2 2 2 2

2 H H C H C

n n n n

+ → ←

+

( )

2 6 2 2

3 1 H H C H C

n n n n

+ → ←

Where n is the number of carbon atoms.

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SLIDE 41

Catalytic Reforming Empirical Kinetic Model

[ ](

)( )( )

atm cat lb hr moles T k P . _ , 34750 21 . 23 exp

1

=       − =

  • [ ](

)( )( )

2 2

. _ , 59600 98 . 35 exp atm cat lb hr moles T kP =       − =

  • [ ](

)( )

. _ , 62300 97 . 42 exp

4 3

cat lb hr moles T k k

P P

=       − = =

  • [ ]

3 3 1

, 46045 15 . 46 exp * atm T P P P K

N H A P

=       − = =

[ ]

1 2

, 12 . 7 8000 exp *

=       − = = atm T P P P K

H N P P

slide-42
SLIDE 42

Catalytic Reforming Rate Law Model

[ ] ( )( )

. _ _ _ _ _ *

2 2 2

cat lb hr paraffins to converted napthene moles K P P P k r

P P H N P

=         − = −

  • [ ]

( )( )

. _ _ _ _ _

3 3

cat lb hr ing hydrocrack by converted paraffins moles P P k r

P P

=       = −

  • [ ]

( )( )

. _ _ _ _ _ *

1 3 1 1

cat lb hr aromatics to converted napthene moles K P P P k r

P H A N P

=         − = −

  • [ ]

( )( )

. _ _ _ _ _

4 4

cat lb hr ing hydrocrack by converted napthenes moles P P k r

N P

=       = −

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SLIDE 43

Excel Model

Partial Flowrates

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SLIDE 44

Excel Model

Partial Pressures

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SLIDE 45

Excel Model

Rate of Reaction Rate Constants Equilibrium Constants

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SLIDE 46

GAMS Model

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SLIDE 47

Catalytic Reforming Model Results

  • Increased

Temperature Dependence

– Endothermic reactions – Increase rate constant – Increase equilibrium constant – Increase concentration

  • f aromatics
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SLIDE 48

Catalytic Reforming Model Results

  • Decreased Pressure

Dependence

– Increase overall reaction rate for hydrocracking – Increases concentration of aromatics

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SLIDE 49

Isomerization

  • Gas-phase catalyzed reaction
  • Transforms a molecule into a different isomer
  • Transforms straight chained isomers into

branched isomers

  • Increases octane rating of gasoline
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SLIDE 50

Isomerization Unit

  • 2 types of catalysts

most commonly used

– Platinum/chlorinated alumina – Platinum/zeolite

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SLIDE 51

Isomerization Unit

  • Feeds

– Butanes – Pentanes – Hexanes – Small amounts Benzene – Make-up Hydrogen

  • Products

– Branched alkanes

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SLIDE 52

Isomerization Unit

isomerization stabilization deisohexanizer Feed

H2 make up

Fuel gas isomerate recycle isomerate

H2 recycle

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SLIDE 53

Isomerization

Isomerate n-C6 Recycle

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SLIDE 54

Isomerization Model

  • Goal

– To create a model that determines the products of the isomerization unit

  • Model inputs

– Temperature (range depends on catalyst used) – Mass flow rate – H2/HC ratio (typical values 0.1-4) – Feed stream concentrations

  • Model outputs

– Product weight percents

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SLIDE 55

Isomerization Model

  • Modeling

– Determine feed partial pressures – N-Butane kinetic model – N-Pentane kinetic model – N-Hexane kinetic model

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SLIDE 56

Isomerization – Partial Pressures

  • Antoine Equation

– log10Po=A-B/(T+C) – T = temperature in ° C – Po = vapor pressure in mmHg

  • Partial Pressure

– Used to determine mole fraction each component

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SLIDE 57

Isomerization – N-Butane Model

  • Bursian (1972)
  • 2

4 2 2 4 1 4 H iC H nC nC

P P K P P K r + − =

N-Butane E (J/mol) A K1 58615.2 3973362 K2 66988.8 25296143

RT E

Ae K

=

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SLIDE 58

Isomerization - N-Pentane Model

  • Aleksandrov (1976)
  • ]

) 1 ( ][ 0000197 . ) ( [

5 5 125 . 2 5 2 5 299 . 1 1861 iC eq nC eq nC nC R TR eq

C K C K t H C K r e K + − − − = =

n-pentane E (kcal/mol) E (J/mol) A K1 10.1 42.2887 4023.872 K2 119.5 500.3465 7331.974

slide-59
SLIDE 59

Isomerization - N-Hexane Model

  • Cheng-Lie (1991)

= =

+ ⋅         − =

5 1 , 5 1 , j j j i i j i j i

C K C K dt dC

5 2,2-DMB 4 2,3-DMB 3 2-MP 2 3-MP 1 n-Hexane

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SLIDE 60

Isomerization Model

  • Rate equations solved using finite

integration

  • Output - concentrations of various isomers

in product stream

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SLIDE 61

Isomerization Model - Excel

slide-62
SLIDE 62

Isomerization Model - GAMS

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SLIDE 63

Isomerization Model Results

  • Temperature Increase

– Pt/Chlorinated Alumina 120-180° C – Pt/Zeolite 250-270° C

Octane # vs. Temperature

70.000 72.000 74.000 76.000 78.000 80.000 82.000 84.000 110 130 150 170 190 210 230 250 270 290 Temperature (C) Octane Number Octane Rating After Unit

slide-64
SLIDE 64

Isomerization Model Results

  • H2/HC Ratio increase

– Range 0.1-4

Octane # vs. H2/HC

70 72 74 76 78 80 82 84 0.5 1 1.5 2 2.5 3 3.5 4 H2/HC Octane # Linear (Octane Number After Unit) Linear (Octane Number Before Unit)

slide-65
SLIDE 65

Modeling Unit Operations

  • Excel

– Excel is not used for overall model due to the problem being too complex for Excel’s Solver

  • CPLEX

– CPLEX is a MIP mathematical optimization program

  • GAMS

– User interface for CPLEX

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SLIDE 66

Option #1 (NLP)

  • Model each unit in Excel
  • Transfer to GAMS (NLP)
  • Add NLP directly into GAMS model
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SLIDE 67

Option #1 (NLP)

  • Problems

– Non-linearities in overall model create difficulty to determine global optimum – Added one unit (HDS)

  • Overall model converged
  • GRM changed (because operating costs were added)
  • Recommendations remained the same

– Added second unit (NPU2)

  • Overall model did not converge
  • Did Not Use
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SLIDE 68
  • For example, a CSTR has the

following equations:

  • X can be shown as a function of

the input variables:

T R E

e k k

⋅ −

⋅ = ( )

A A

F r V X − ⋅ =

Linearization of a Non-Linear Problem

) , , (

B A C

C T f X =

2 5 . B A A

C C k r ⋅ ⋅ = −

slide-69
SLIDE 69

Linearization of a Non-Linear Problem

  • To linearize, discretize the input variables

– Where Z is a binary variable

⋅ =

) , , (

) , , ( ) , , (

B A

C C T B A B A

C C T f C C T Z X

T R E

e k k

⋅ −

⋅ =

2 5 . B A A

C C k r ⋅ ⋅ = − ( )

A A

F r V X − ⋅ =

1 ) , , (

) , , (

=

B A

C C T B A C

C T Z

T = 500 F 600 F 700 F 800 F 900 F CA0 = 0.92 mol/L 0.94 mol/L 0.96 mol/L 0.98 mol/L 1.00 mol/L CB0 = 0.50 mol/L 0.55 mol/L 0.60 mol/L 0.65 mol/L 0.70 mol/L

slide-70
SLIDE 70

Non-Linearities in Unit Operations

  • CSTR
  • Catalytic Reformer

T R E

e k k

⋅ −

⋅ = ( )

A A

F r V X − ⋅ =

2 5 . B A A

C C k r ⋅ ⋅ = −

      − = T kP 34750 21 . 23 exp

1

     − = T kP 59600 98 . 35 exp

2

     − = = T k k

P P

62300 97 . 42 exp

4 3

  • N

H A P

P P P K

3 1

* =

H N P P

P P P K *

2 =

        − = −

2 2 2

*

P P H N P

K P P P k r

     = − P P k r

P P3 3

       − = −

1 3 1 1

*

P H A N P

K P P P k r

     = − P P k r

N P4 4

slide-71
SLIDE 71

Option #2 (MIP)

  • Take Excel model
  • Write MIP utilizing table of possible variables
  • Add MIP directly into GAMS model

Unit Model in Excel Unit Model in GAMS (MIP) Overall Model GAMS Unit Models (MIP) Table of Possible Operating Conditions Table of Possible Operating Conditions

slide-72
SLIDE 72

Option #2 (MIP)

  • Did not attempt to use

– Overall model would theoretically work – Model would become extremely long – Would require more memory and resources – Less user friendly than option #3

slide-73
SLIDE 73

Option #3 (MIP Brute Force)

  • Take Excel model
  • Model MIP in GAMS
  • Have MIP write to an overall table
  • Utilize binary variables in overall model to select

variables based on the table and constraints

Unit Model in Excel Unit Model in GAMS (MIP) Overall Model Table (Results, Operating Variables) Table Table of Possible Operating Conditions

slide-74
SLIDE 74

Table Generation

⋅ =

) , , (

) , , ( ) , , (

B A

C C T B A B A

C C T X C C T Z X

T = CA0 = 0.50 mol/L 0.55 mol/L 0.60 mol/L 0.65 mol/L 0.70 mol/L 500 F 0.92 mol/L 0.74 0.22 0.75 0.54 0.93 500 F 0.94 mol/L 0.10 0.39 0.79 0.32 0.38 500 F 0.96 mol/L 0.72 0.70 0.06 0.28 0.22 500 F 0.98 mol/L 0.54 0.57 0.53 0.24 0.22 500 F 1.00 mol/L 0.91 0.41 0.80 0.66 0.97 600 F 0.92 mol/L 0.33 0.12 0.09 0.77 0.08 600 F 0.94 mol/L 0.04 0.70 0.78 0.79 0.58 600 F 0.96 mol/L 0.48 1.00 0.00 0.52 0.24 600 F 0.98 mol/L 0.86 0.40 0.85 0.10 0.27 600 F 1.00 mol/L 0.15 0.42 0.91 0.72 0.59 700 F 0.92 mol/L 0.00 0.62 0.69 0.29 0.85 700 F 0.94 mol/L 0.73 0.78 0.47 0.93 0.55 700 F 0.96 mol/L 0.83 0.45 0.46 0.54 0.64 700 F 0.98 mol/L 0.94 0.43 0.69 0.25 0.88 700 F 1.00 mol/L 0.25 0.01 0.61 0.26 0.07 800 F 0.92 mol/L 0.25 0.64 0.55 0.40 0.68 800 F 0.94 mol/L 0.37 0.87 0.14 0.31 0.96 800 F 0.96 mol/L 0.52 0.58 0.37 0.61 0.71 800 F 0.98 mol/L 0.46 0.20 0.17 0.99 0.37 800 F 1.00 mol/L 0.04 0.82 0.81 0.81 0.86 900 F 0.92 mol/L 0.83 0.39 0.50 0.57 0.10 900 F 0.94 mol/L 0.27 0.52 0.35 0.81 0.96 900 F 0.96 mol/L 0.71 0.09 0.63 0.45 0.03 900 F 0.98 mol/L 0.61 0.47 0.30 0.29 0.09 900 F 1.00 mol/L 0.30 0.35 0.52 0.84 0.02 CB0 =

slide-75
SLIDE 75

Option #3 (MIP Brute Force)

  • Currently being used

– Offers ease of use for the overall model – Drawback - more files are required to run the model

  • 26 tables utilized
slide-76
SLIDE 76

Specific Modeling Issues

  • “Best Choice” scenario
  • Mass Balance
  • Blending
  • Additions
slide-77
SLIDE 77

“Best Choice” Scenario

  • Unit operations flow rates chosen by which

scenario is nearest to the actual flow rate

  • Allows for degrees of freedom in crude

purchasing

Foverall Ffg,out

Fref,unit Flpg,unit Ffg,unit

Flpg,out Fref,out

Funit

slide-78
SLIDE 78

“Best Choice” Scenario

  • F = flow rates
  • d = difference between discretized unit flow rates

d F F

  • verall

unit

≤ −

d F F

unit

  • verall

≤ −

F = 15000 m3/d 16000 m3/d 17000 m3/d 18000 m3/d 19000 m3/d

500 2 15000 16000 . . 2 1 2 = − = − = g e F F d

slide-79
SLIDE 79

Mass Balance (CRU2, CRU3, ISOU)

Foverall Ffg,out

  • Solving the mass balance (2 options)

– Foverall = Fout

  • Requires a non-linear equation (Z*Foverall)
  • Linearization possible, but requires massive

amounts of memory (takes the program a long time to run)

Fref,unit Flpg,unit Ffg,unit

Flpg,out Fref,out

Funit

slide-80
SLIDE 80

Linearization of Z*Foverall

( ) ( )

∑ ∑

⋅ = Γ ⋅ = ≥ Γ − ≤ − ⋅ − Γ − ≥ Γ ≤ ⋅ − Γ

) , , ( ) , , ( 10

) , , ( ) , , ( 10 1 ) , , ( ) , , ( 1 ) , , ( ) , , ( ) , , ( ) , , (

c b a

  • verall

c b a

  • verall
  • verall

F c b a Z c b a where x c b a F c b a Z x c b a F c b a c b a Z x c b a

slide-81
SLIDE 81

Mass Balance (CRU2, CRU3, ISOU)

  • Successful solution

– Advantage - requires far less memory – Disadvantage - mass is not completely balanced

  • Model not based on

mass flow rates

  • Volumetric balances are

inexact

  • If large amount of flow

rate scenarios used, the error is minimized

– Large amounts of scenarios does not slow down model

unit reformate

  • ut

reformate

F F

, ,

=

Foverall

Funit

Ffg,out

Fref,unit Flpg,unit Ffg,unit

Flpg,out Fref,out

slide-82
SLIDE 82

Blending Model

95 91 , = = = ⋅ ≥ ⋅ + ⋅ + ⋅

ISOG SUPG x tot c c b b a a

ON ON SUPG ISOG x ON F ON F ON F ON F

  • ONa dependant on Z, therefore Z*F appears again

– Linearization used (only 3 required this time)

slide-83
SLIDE 83

Linearization of Z*Foverall

( ) ( )

∑ ∑

⋅ = Γ ⋅ = ≥ Γ − ≤ − ⋅ − Γ − ≥ Γ ≤ ⋅ − Γ

) , , ( ) , , ( 10

) , , ( ) , , ( 10 1 ) , , ( ) , , ( 1 ) , , ( ) , , ( ) , , ( ) , , (

c b a

  • verall

c b a

  • verall
  • verall

F c b a Z c b a where x c b a F c b a Z x c b a F c b a c b a Z x c b a

slide-84
SLIDE 84

Additions

  • Revised Fuel Balance

– Fuel Gas and Fuel Oil burned

  • Added Operating Costs associated with

compression

  • Added Hydrogen Balance
slide-85
SLIDE 85

Results

  • Executed using CPLEX

– Approximately 50 minutes to reach integer solution – Approximately 2 hours to reach optimal solution

slide-86
SLIDE 86

It Works!

slide-87
SLIDE 87

Results

Over 1*1016 combinations

  • f operating conditions
slide-88
SLIDE 88

Planning

  • Currently planning is optimized and then

unit operations are optimized

  • Planning is highly dependent on unit
  • perations

– e.g. turnarounds, unit capacities

slide-89
SLIDE 89

Results

  • GRM has increased

– Optimizing unit operations is more efficient

GRM Model without Unit Operations $16,492,336.72 Model with Unit Operations $34,130,901.06

slide-90
SLIDE 90

Results

  • Purchased crudes and intermediates

1 2 3 Oman (OM): 167734.3 167339.3 165082.6 Tapis (TP): 13427.7 14317 19397.5 Labuan (LB): Seria Light (SLEB): 95392.2 95392.2 95392.2 Phet (PHET): 57235.3 57235.3 57235.3 Murban (MB): 95392.2 95392.2 95392.2 MTBE: 13662 13700.7 13921.7 DCC: 68088 68301.8 69523.2 Model without Unit Operations 1 2 3 Oman (OM): 244486.2 262303.1 267899.8 Tapis (TP): 32853.3 41126.2 47392.2 Labuan (LB): 9041.4 Seria Light (SLEB): 95392.2 95392.2 95392.2 Phet (PHET): 57235.3 57235.3 57235.3 Murban (MB): 95392.2 95392.2 95392.2 MTBE: 18266 19392.8 20404.2 DCC: 87059.5 91153.7 93941.2 Model with Unit Operations

slide-91
SLIDE 91

Results

HDS FOVS FO2 GASOLINE POOL DIESEL POOL CDU2 CDU3 MB

FG LPG Naphtha FO Kero DO

NPU

LN HN

ISOU CRU

HN FG REF LPG

KTU

ISO LN Kero IHSD

MTBET DCCT ISOG SUPG HSD JP1 FO1

Products Intermediates

PHET SLEB LB TP OM

Crudes Kero FO Kero

slide-92
SLIDE 92

Discussion

Reformer Sensitivity 86 88 90 92 94 96 98 100 Octane Number

Varying Flow (15-25 Mm3/day) Varying Pressure (400-800 psi) Varying Temperature (800-980 ° F) Linear (Varying Flow (15-25 Mm3/day))

  • Poly. (Varying Pressure (400-800 psi))
  • Poly. (Varying Temperature (800-980 °

F))

slide-93
SLIDE 93

Discussion

  • Optimizing unit operations adds another

dimension to optimize refinery processing

  • Can provide more thorough insight for

decision making

slide-94
SLIDE 94

Acknowledgments

  • Dr. Miguel Bagajewicz
  • DuyQuang Nguyen
  • Mike Mills
  • Sunoco Refinery (Tulsa, OK)

– John Paris

slide-95
SLIDE 95

Please, No Questions! ….Just Kidding