aspenhysyscleanfuels2006 5 usr

8/10/2019 AspenHYSYSCleanFuels2006 5 Usr

1/58

Aspen HYSYSClean FuelsPropertyPackage

Users Guide


2/58

Version Number: 2006.5October 2007

Copyright (c) 1981-2007 by Aspen Technology, Inc. All rights reserved.

AspenTech, Aspen Accounting.21, Aspen ACM Model Export, Aspen ACOL, Aspen ACX Upgrade to ACOL, Aspen Adsim,Aspen Advisor, Aspen Aerotran, Aspen Alarm & Event, Aspen APLE, Aspen Apollo, Aspen AtOMS, Aspen Batch and EventExtractor, Aspen Batch Plus, Aspen Batch.21, Aspen Batch.21 CBT, Aspen BatchCAD, Aspen BatchSep, Aspen Blend ModelLibrary, Aspen Blend, Aspen BP Crude Oil Database, Aspen Calc CBT, Aspen Calc, Aspen Capable-to-Promise, Aspen CatRef,Aspen Chromatography, Aspen Cim-IO Core, Aspen Cim-IO for @AGlance, Aspen Cim-IO for ABB 1180/1190 via DIU, AspenCim-IO for Bailey SemAPI, Aspen Cim-IO for DDE, Aspen Cim-IO for Eurotherm Gauge via DCP, Aspen Cim-IO for Fisher-Rosemount Chip, Aspen Cim-IO for Fisher-Rosemount RNI, Aspen Cim-IO for Foxboro FOXAPI, Aspen Cim-IO for G2, AspenCim-IO for GE FANUC via HCT, Aspen Cim-IO for Hitachi Ex Series, Aspen Cim-IO for Honeywell TDC 3000 via HTL/access,Aspen Cim-IO for Intellution Fix, Aspen Cim-IO for Measurex MCN, Aspen Cim-IO for Measurex ODX, Aspen Cim-IO for MooreApacs via Nim (RNI), Aspen Cim-IO for OPC, Aspen Cim-IO for PI, Aspen Cim-IO for RSLinx, Aspen Cim-IO for SetCim/InfoPlus-X/InfoPlus.21, Aspen Cim-IO for Toshiba Tosdic, Aspen Cim-IO for ULMA 3D, Aspen Cim-IO for Westinghouse, AspenCim-IO for WonderWare InTouch, Aspen Cim-IO for Yokogawa ACG10S, Aspen Cim-IO for Yokogawa EW3, Aspen CollaborativeForecasting, Aspen Compliance.21, Aspen COMThermo, Aspen CPLEX Optimizer, Aspen CPLEX Optimizer for DPO, Aspen CrudeManager, Aspen Crude Trading & Marketing, Aspen Custom Modeler, Aspen Data Source Architecture, Aspen DecisionAnalyzer, Aspen Demand Manager, Aspen DISTIL, Aspen Distribution Scheduler, Aspen DMCplus, Aspen DMCplus CBT,Aspen DMCplus Composite, Aspen Downtime Monitoring Application, Aspen DPO, Aspen Dynamics, Aspen eBRS, AspenFCC, Aspen FIHR, Aspen FLARENET, Aspen Fleet Operations Management, Aspen FRAN, Aspen Fuel Gas Optimizer, AspenGrade-IT, Aspen Harwell Subroutine Library, Aspen Hetran, Aspen HPI Library, Aspen HTFS Research Network, Aspen HX-NetOperations, Aspen HX-Net, Aspen Hydrocracker, Aspen Hydrotreater, Aspen HYSYS Amines, Aspen HYSYS Crude, AspenHYSYS Data Rec, Aspen HYSYS Dynamics, Aspen HYSYS Johnson Matthey Reactor Models, Aspen HYSYS OLGAS 3-Phase,Aspen HYSYS OLGAS, Aspen HYSYS OLI Interface, Aspen HYSYS Optimizer, Aspen HYSYS Tacite, Aspen HYSYS UpstreamDynamics, Aspen HYSYS Upstream, Aspen HYSYS, Aspen Icarus Process Evaluator, Aspen Icarus Project Manager, AspenIcarus Project Scheduler, Aspen InfoPlus.21, Aspen Inventory Management & Operations Scheduling, Aspen InventoryPlanner, Aspen IQmodel Powertools, Aspen IQ, Aspen Kbase, Aspen Lab.21, Aspen MBO, Aspen MPIMS, AspenMultivariate Server, Aspen MUSE, Aspen OnLine, Aspen Open Simulation Environment Base, Aspen Operations Manager -Event Management, Aspen Operations Manager - Integration Infrastructure, Aspen Operations Manager - IntegrationInfrastructure Advisor, Aspen Operations Manager - Integration Infrastructure Base, Aspen Operations Manager - IntegrationInfrastructure COM, Aspen Operations Manager - Integration Infrastructure Files, Aspen Operations Manager - Integration

Infrastructure IP.21/SAP-PPPI, Aspen Operations Manager - Integration Infrastructure IP21, Aspen Operations Manager -Integration Infrastructure OPC, Aspen Operations Manager - Integration Infrastructure Orion, Aspen Operations Manager -Integration Infrastructure PIMS, Aspen Operations Manager - Integration Infrastructure Relational Databases, Aspen OperationsManager - Integration Infrastructure SAP R3, Aspen Operations Manager - Integration Infrastructure System Monitoring, AspenOperations Manager - Integration Infrastructure Utilities, Aspen Operations Manager - Performance Scorecarding, AspenOperations Manager - Role Based Visualization MS SharePoint, Aspen Operations Manager - Role Based Visualization TIBCO,Aspen Operations Tracking, Aspen Order Credit Management, Aspen Orion Planning, Aspen Orion XT, Aspen OSE - Oil & GasAdapter, Aspen OSE - Oil & Gas Optimizer, Aspen PEP Process Library, Aspen PIMS Advanced Optimization, Aspen PIMS CPLEXOptimizer, Aspen PIMS Distributed Processing, Aspen PIMS Enterprise Edition, Aspen PIMS Global Optimization, Aspen PIMSMixed Integer Programming, Aspen PIMS Simulator Interface, Aspen PIMS Solution Ranging, Aspen PIMS SubmodelCalculator, Aspen PIMS XNLP Optimizer, Aspen PIMS XPRESS Optimizer, Aspen PIMS-SX, Aspen PIMS, Aspen PIMSXCHG, AspenPIPE, Aspen Plant Planner & Scheduler, Aspen Plant Scheduler Lite, Aspen Plant Scheduler, Aspen Plus HTRI Interface, AspenPlus OLI Interface, Aspen Plus Optimizer, Aspen Plus SPYRO Equation Oriented Interface, Aspen Plus, Aspen Plus CBT, AspenPolymers Plus, Aspen PPIMS, Aspen Process Explorer, Aspen Process Explorer CBT, Aspen Process Manual Applied Rheology,Aspen Process Manual Bulk Solids Handling, Aspen Process Manual Crystallization, Aspen Process Manual Drying, Aspen ProcessManual Gas Cleaning, Aspen Process Manual Internet Mode, Aspen Process Manual Intranet Mode, Aspen Process ManualMini-Manuals, Aspen Process Manual Slurry Handling, Aspen Process Manual Solid Liquid Separation, Aspen Process ManualSolvent Extraction, Aspen Process Manual Waste Water Treatment, Aspen Process Order, Aspen Process Recipe, Aspen ProcessTools, Aspen Product Tracking, Aspen Production Control Web Server, Aspen ProFES 2P Wax, Aspen ProFES Tranflo, Aspen

Profile.21, Aspen Properties, Aspen Pumper Log, Aspen Q Server, Aspen Quality Management, Aspen RateSep, AspenRefSYS CatCracker, Aspen RefSYS Hydrocracker, Aspen RefSYS Reformer, Aspen RefSYS, Aspen Report Writer, Aspen RetailAutomated Stock Replenishment, Aspen Retail Resource Scheduling Optimization, Aspen Richardson Cost Factor Manual, AspenRichardson General Construction Estimating Standards, Aspen Richardson Process Plant Construction Estimating Standards,Aspen Richardson WinRace Database, Aspen RTO Watch, Aspen SCM, Aspen SmartStep Advanced, Aspen Specialty ProductsAutomated Stock Replenishment, Aspen Specialty Products Resource Scheduling Optimization, Aspen Split, Aspen State SpaceController, Aspen STX Upgrade to TASC, Aspen SULSIM, Aspen Supply Chain Analytics - Demand Management, AspenSupply Chain Analytics - Plant Scheduling, Aspen Supply Chain Analytics - S&OP, Aspen Supply Chain Analytics - SupplyPlanning, Aspen Supply Chain Connect, Aspen Supply Planner, Aspen Supply Planning - Strategic Analyzer, Aspen TankManagement, Aspen TASC, Aspen Teams, Aspen TICP, Aspen Transition Manager, Aspen Utilities, Aspen Voice FulfillmentManagement, Aspen Watch, Aspen Water, Aspen Web Fulfillment Management, Aspen XPIMS, Aspen XPRESS Optimizer,Aspen XPRESS Optimizer for DPO, Aspen Zyqad Development, Aspen Zyqad, aspenONE Product Trading & Blending, SLM,SLM Commute, SLM Config Wizard, the aspen leaf logo and Plantelligence are trademarks or registered trademarks of Aspen


3/58

Technology, Inc., Burlington, MA.

All other brand and product names are trademarks or registered trademarks of their respectivecompanies.

This manual is intended as a guide to using AspenTechs software. This documentation contains

AspenTech proprietary and confidential information and may not be disclosed, used, or copied withoutthe prior consent of AspenTech or as set forth in the applicable license agreement. Users are solelyresponsible for the proper use of the software and the application of the results obtained.

Although AspenTech has tested the software and reviewed the documentation, the sole warranty forthe software may be found in the applicable license agreement between AspenTech and the user.ASPENTECH MAKES NO WARRANTY OR REPRESENTATION, EITHER EXPRESSED OR IMPLIED,WITH RESPECT TO THIS DOCUMENTATION, ITS QUALITY, PERFORMANCE,MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE.

Aspen Technology, Inc.200 Wheeler RoadBurlington, MA 01803-5501USAPhone: (781) 221-4300Website http://www.aspentech.com
http://www.aspentech.com/http://www.aspentech.com/


4/58


5/58

-v

-v

Technical Support

Online Technical Support Center ........................................................ vi

Phone and E-mail .............................................................................. vii


6/58

-vi

-vi

Online Technical Support

CenterAspenTech customers with a valid license and software

maintenance agreement can register to access the Online

Technical Support Center at:

http://support.aspentech.com

You use the Online Technical Support Center to:

Access current product documentation.

Search for technical tips, solutions, and frequently askedquestions (FAQs).

Search for and download application examples. Search for and download service packs and product

updates.

Submit and track technical issues.

Search for and review known limitations.

Send suggestions.

Registered users can also subscribe to our Technical Support e-

Bulletins. These e-Bulletins proactively alert you to important

technical support information such as:

Technical advisories

Product updates

Service Pack announcements Product release announcements
http://support.aspentech.com/http://support.aspentech.com/


7/58

-vii

-vii

Phone and E-mailCustomer support is also available by phone, fax, and e-mail forcustomers who have a current support contract for their

product(s). Toll-free charges are listed where available;

otherwise local and international rates apply.

For the most up-to-date phone listings, please see the Online

Technical Support Center at:

http://support.aspentech.com

Support Centers Operating Hours

North America 8:00 - 20:00 Eastern time

South America 9:00 - 17:00 Local time

Europe 8:30 - 18:00 Central European time

Asia and Pacific Region 9:00 - 17:30 Local time
http://support.aspentech.com/http://support.aspentech.com/


8/58

-viii

-viii


9/58

ix

Table of Contents

Technical Support..................................................... v

Online Technical Support Center ............................vi

Phone and E-mail................................................vii

1 Introduction.........................................................1-1

1.1 Meeting New Sulphur Levels in Motor Gasoline ..... 1-3

2 Gasoline Fractionation..........................................2-1

2.1 Gasoline Sulphur Species Distribution ................. 2-2

2.2 Light/Medium Gasoline Fractionation................... 2-5

2.3 Improve Fractionator Design.............................. 2-8

3 Clean Fuels Property Package............................3-1

3.1 Introduction .................................................... 3-2

3.2 Thermodynamic Model ...................................... 3-2

4 Clean Fuels Pkg Extension ....................................4-1

4.1 Using the Clean Fuels Pkg Extension................... 4-2

4.2 Clean Fuels Pkg Extension User Interface ............ 4-3

4.3 Clean Fuels Pkg Property View ........................... 4-4

5 Clean Fuels Pkg Tutorial .......................................5-1

5.1 Introduction .................................................... 5-2

5.2 Flowsheet Setup .............................................. 5-3

5.3 Modeling the Gasoline Fractionator ....................5-10

5.4 Plot Utility......................................................5-15

A References ...........................................................A-1

Index.................................................................... I-1


10/58

x


11/58

Introduction 1-1

1-1

1 Introduction

1.1 Meeting New Sulphur Levels in Motor Gasoline.............................. 3


12/58

1-2

1-2

The increasing environmental concern of sulphur content in

petroleum products mean refiners are needing to find better

ways of managing sulphur pool target levels in gasoline. The

complexity of modeling these processes with the accuracy in thevery low ppm region requires highly accurate thermodynamic

methods for modeling and optimization. To meet the need for

increased model reliability, a new property package, the Clean

Fuels Pkg, has been developed specifically for systems of thiols

and hydrocarbons. The new property package features new

methods, estimation routines as well as extensive new

databases of pure component properties and mixtures.

This user guide is a comprehensive guide that provides the

steps needed to use the Clean Fuels Pkg in a HYSYS flowsheet.

To apply the Clean Fuels Extension efficiently, the guide

describes the property package property views as well as itscapabilities. A simple flowsheet model of a gasoline fractionator

is constructed using the Clean Fuels Pkg and the steps of its

construction are given in the tutorial. The tutorial presents the

basic steps needed to build the flowsheet model. Each property

view is explained on a page-by-page basis to give a complete

description of the data requirements in order to use the property

package efficiently. This User Guide does not detail HYSYS

procedures and assumes the user is familiar with the HYSYS

environment and its conventions. Here you will find the

information required to build a HYSYS flowsheet and work

efficiently within the simulation environment.


13/58

Introduction 1-3

1-3

1.1 Meeting New Sulphur

Levels in MotorGasolineWith new strict global-wide legislation regulating undesirable

emissions from internal combustion engines, refineries are

facing challenging design decisions to meet lower sulphur

targets in motor gasoline. With these regulations continuing to

evolve, reducing sulphur to target levels will likely involve some

of the highest capital costs for refiners.

During the early 1990s gasoline sulphur levels wereapproximately 340 ppmw [1]. With new levels set in 2000,

refiners are reducing sulphur to 150 ppmw. By 2006, the US

EPA proposes to reduce sulphur to 30 ppmw with phased

reductions beginning in 2004. European regulations call for

reductions to 50 ppmw by 2005 while Canadian regulations

require 30 ppmw by 2004 [1]. Farther ahead, the US EPA has

called for even lower targets of 10 ppmw. Continuously lower

levels of gasoline sulphur present new challenges to develop and

identify viable low cost solutions for reduced gasoline sulphur

content in motor gasoline.

Effective solutions to manage gasoline sulphur content involvechoosing the best technology options for sulphur removal, as

well as selecting designs that best fit the operating philosophy

for refiners. Important to gasoline sulphur management

strategies is understanding how the various sulphur species are

distributed in fractionator gasoline cuts which is critical in

determining the optimum operating conditions of gasoline

fractionators.

As sulphur content of gasoline is reduced, gasoline fractionation

will become increasingly important. Key in the optimum design

of new or existing equipment is the construction of accurate

flowsheets of gasoline fractionation processes. Fundamental tothe construction of flowsheet models is the accurate VLE

representation of thiol containing mixtures of hydrocarbons.


14/58

1-4 Meeting New Sulphur Levels in

1-4


15/58

Gasoline Fractionation 2-1

2-1

2 Gasoline

Fractionation

2.1 Gasoline Sulphur Species Distribution............................................2

2.2 Light/Medium Gasoline Fractionation ............................................ 5

2.3 Improve Fractionator Design ......................................................... 8


16/58

2-2 Gasoline Sulphur Species

2-2

2.1 Gasoline Sulphur

Species DistributionVarious sulphur compounds are distributed throughout the

gasoline TBP range. The amount of sulphur species in motor

gasoline depends on a number of factors including the crude

source, treating methods and gasoline cut point. The boiling

range of FCC gasoline does not change significantly with sulphur

levels2. Therefore knowing the temperature range where the

various sulphur species distil and how much of each sulphur

species is present at a given TBP temperature is important in

operating fractionation equipment that meet sulphur pool target

levels. A list of sulphur compounds is shown in the table below

together with the hydrocarbon boiling point ranges and HYSYS

component information.

Essential for the accurate prediction of azeotropes occurringbetween thiols and hydrocarbons is the accurate calculation of

pure component vapor pressures. For this, the most up to date

Component nameHYSYS Sim

NameNPB F

BPT Range

F

HYSYS Comp

IDFormula

Sulphur Components in Light Gasoline

Ethyl Mercaptan E-Mercaptan 95.09 70-90 354 C2H6S

Dimethyl Sulfide diM-Sulphide 99.23 75-80 380 C2H6S

Iso-propyl Mercaptan 2C3Mercaptan 126.61 110-130 3162 C3H8S

Tert-butyl Mercaptan t-B-Mercaptan 147.59 120-150 524 C4H10S

Methyl Ethyl Sulphide M-E-Sulfide 151.97 130-140 381 C3H8S

n-Propyl Mercpatan nPMercaptan 150.89 115-130 389 C3H8SThiophene Thiophene 183.29 140-200 384 C4H4S

Iso-Butyl Mercaptan 2-M-1C3Thiol 191.21 180-200 732 C4H10S

n-Butyl Mercaptan nBMercaptan 209.23 185-200 390 C4H10S

Dimethyl disulfide diMdiSulphid 229.53 190-200 385 C2H6S2

2-Methyl Thiophene 2MThiophene 234.59 200-250 733 C5H6S

3-Methyl Thiophene 3MThiophene 239.81 210-270 734 C5H6S

Tetrahydrothiophene Thiolane 250.01 220-260 526 C4H8S

1-Pentyl Mercaptan 1Pentanthiol 259.95 245-255 525 C5H12S

Hexyl Mercaptan 1Hexanethiol 306.77 290-340 847 C6H14S

Benzothiopene ThioNaphtene 427.81 400+ 3116 C8H6S


17/58


2-3

pure component data (DIPPR) was used in the development of

the Clean Fuels Property Package methods. A list of sulphur

species supported in HYSYS for the Clean Fuels Property

Package is shown in the table below.

Formula Component Name DIPPR ID HYSYS ID

CH4S METHYL MERCAPTAN 1801 353

C2H6S ETHYL MERCAPTAN 1802 354

C3H8S n-PROPYL MERCAPTAN 1803 389

C4H10S tert-BUTYL MERCAPTAN 1804 524

C4H10S ISOBUTYL MERCAPTAN 1805 732

C4H10S sec-BUTYL MERCAPTAN 1806 731

C6H14S n-HEXYL MERCAPTAN 1807 847

C9H20S n-NONYL MERCAPTAN 1808 3068

C8H18S n-OCTYL MERCAPTAN 1809 871

C3H8S ISOPROPYL MERCAPTAN 1810 3162

C3H8S ISOPROPYL MERCAPTAN 1810 695

C6H12S CYCLOHEXYL MERCAPTAN 1811 3280

C7H8S BENZYL MERCAPTAN 1812 3319

C3H8S METHYL ETHYL SULFIDE 1813 381

C4H10S METHYL n-PROPYL SULFIDE 1814 730

C6H14S DI-n-PROPYL SULFIDE 1817 846

C4H10S DIETHYL SULFIDE 1818 382

C2H6S DIMETHYL SULFIDE 1820 380

C4H4S THIOPHENE 1821 384

C8H6S BENZOTHIOPHENE 1822 3116

C4H10S2 DIETHYL DISULFIDE 1824 383

C11H24S UNDECYL MERCAPTAN 1825 958

C10H22S n-DECYL MERCAPTAN 1826 945

C5H12S n-PENTYL MERCAPTAN 1827 525

C2H6S2 DIMETHYL DISULFIDE 1828 385

C6H14S2 DI-n-PROPYL DISULFIDE 1829 848

C12H26S n-DODECYL MERCAPTAN 1837 3013

C8H18S tert-OCTYL MERCAPTAN 1838 3373

C7H16S n-HEPTYL MERCAPTAN 1839 865

C4H10S n-BUTYL MERCAPTAN 1841 390

C6H6S PHENYL MERCAPTAN 1842 391

C4H8S TETRAHYDROTHIOPHENE 1843 526

C2H6OS DIMETHYL SULFOXIDE 1844 950C3H6O2S 3-MERCAPTOPROPIONIC ACID 1873 3153

COS CARBONYL SULFIDE 1893 355


18/58

2-4 Gasoline Sulphur Species

2-4

Quantifying sulphur species by hydrocarbon boiling range

requires fractionating 20-30 narrow boiling range (10-20F)using an ASTM D2892(TBP) column or TBP column with 15

theoretical stages and a 5/1 reflux ratio2. A highly fractionated

gasoline sample will be discontinuous up to about 390F due tothe different sulphur species boiling point ranges. Sulphur

distribution, sulphur species and hydrocarbon TBP can then be

plotted using this information. Sulphur species content in

gasoline change from primarily mercaptans in the low boiling

range IBP-140F material to thiophenic compounds in the 140-390F, and benzothiophenes and substituted benzothiophenes inthe 390-430F heavy gasoline. Above 390F the total sulphurincreases significantly with temperature.

H2S HYDROGEN SULFIDE 1922 15

CS2 CARBON DISULFIDE 1938 364

C12H8S DIBENZOTHIOPHENE 2823 3441

C12H26S tert-DODECYL MERCAPTAN 2838 3460

C5H6S 2-METHYLTHIOPHENE 2844 3216




C2H4O2S THIOGLYCOLIC ACID 2872 3134

C5H9NS N-METHYLTHIOPYRROLIDONE 3888 3223

C4Cl4S TETRACHLOROTHIOPHENE 4877 3169

C4H10O2S THIODIGLYCOL 6855 3195

C2H6OS 2-MERCAPTOETHANOL 6858 3138

C4H10OS ETHYLTHIOETHANOL 6859 3192

C2H6S2 1,2-ETHANEDITHIOL 6860 3139

Formula Component Name DIPPR ID HYSYS ID


19/58


2-5

2.2 Light/Medium Gasoline

FractionationAs sulphur content of motor gasoline is mandatorily reduced,

gasoline fractionation will become increasingly more important.

Light gasoline thiophene content determines the total sulphur

content of a treated gasoline stream. The IBP-140Fhydrocarbons contain primarily C2and C3mercaptans and up to

90% of these mercaptans can be extracted in caustic treating

processes. Thiophene however can not be extracted using these

methods. The thiophene NBP is 183.29F. Due to stronghydrocarbon-thiol molecular interactions, thiophene distils with

hydrocarbons between 140F and 200F. Peak thiopheneconcentration occurs at about 165-170F boiling range2.Thiophene content varies with each crude and the amount of

hydrotreating, however it can represent up to 75% of the

sulphur in the 140-180F hydrocarbons. Therefore 140F+material in light gasoline increases treated stream sulphur

content.

A simulated plot of an FCC naphtha and the distribution of

thiophene with increasing hydrocarbon boiling point is shown in

Figure 2.1. The plot was constructed using a simulation model

of an Oldershaw still with 70 theoretical stages at 20/1 reflux

ratio and equal narrow boiling range cuts of 5% volume distilled.Results are shown in the table below. Qualitatively, the sulphur

distribution curve of FCC gasoline increases rapidly, with

thiophene beginning to boil with hydrocarbons at approximately

140F as shown inFigure 2.1. The predicted peak sulphurconcentration occurs at 168F. Sharp fractionation of the light/medium gasoline can increase yield significantly while still

meeting treated product sulphur levels2.


20/58

2-6 Light/Medium Gasoline

2-6

The table below shows theSimulated Distillation Data of

Thiophene Distribution in a FCC Gasoline.

Fractionation of light/medium gasoline fractionation requires a

dedicated gas plant column. The column efficiency will

determine light gasoline yield and thiophene concentration in

gasoline. Medium/heavy gasoline fractionation is performed in

the main fractionator with heavy gasoline produced as a side cut

product, to minimize energy consumption and capital costs.

Figure 2.1: Simulated Thiophene Peak of FCC Gasoline

Percent Distilled

Volume

Temperature

F

Sulphur ppm

wt

20% 95.60 0.00

25% 117.15 0.00

30% 142.28 0.1135% 151.77 10.9

40% 168.61 1354.0

45% 182.07 36.8

50% 196.67 0.00

55% 220.88 0.00


21/58


2-7

Light/medium gasoline fractionation separates feed to the

casuistic extraction process from the medium boiling range

gasoline. The caustic extraction process converts mercaptans to

disulfides, which are easily extracted. Caustic extraction can

remove between 80-90% of the C2/C3 mercaptans.

The amount of thiophene entering the feed caustic extraction

process or its equivalent leaves with the treated product stream.

Thiophene begins to distil with C6 hydrocarbons boiling above140F. Thiophene content peaks in the 165-170F boiling rangeso increasing levels of 140F+ material increases the treatedproduct stream sulphur level. If thiophene content and not the

mercaptan extraction efficiency controls the treated product

sulphur level, then the light gasoline 140-160F boiling materialmust be controlled to meet product stream sulphur targets. The

140-160F boiling range hydrocarbons make up 7-9 wt% of thetotal FCC gasoline2, light gasoline yield can be increased

significantly with good fractionation by lowering the amount of

140-170F boiling material in light gasoline product which allowshigher light gasoline yield. Sharp fractionation is achieved

through an appropriate number of column trays, controllingreflux and energy input.

The table that lists the sulphur compounds together withthe hydrocarbon boiling point ranges and HYSYS component

information in Section 2.1 - Gasoline Sulphur SpeciesDistribution, lists the sulphur species that are present inlight gasoline.


22/58

2-8 Improve Fractionator Design

2-8

2.3 Improve Fractionator

DesignHere the fractionation objective is to determine the optimum

number of trays and reflux that will result in sharp fractionation

of light and medium gasoline. The optimum values are achieved

using accurate VLE models.

Understanding how sulphur is distributed in gasoline is the first

step in determining the gasoline cut point to achieve the

necessary sharp fractionation between light and medium

gasoline. In designing a gasoline fractionation column, the

design objective is to ensure that thiophene is controlled in the

gasoline distillate. Even small amounts of thiophene contained

in the light fraction can add significantly to gasoline sulphur

levels.

Because of the strong molecular interactions between

hydrocarbons and sulphur containing compounds these mixtures

are non-ideal and can form azeotropes that are difficult to model

accurately. Typically an activity coefficient model would best

represent a non-ideal system. However because of the presence

of alkanes, olefins and oils as well as non-condensable

components in systems of gasoline, an equation of state is

always preferred for calculation of hydrocarbon binaries. An

equation of state however is not suitable for thiol-hydrocarbon

binary pairs. By combining the equation of state with an activity

model through a new Helmholtz Excess Energy AEmixing rule

and using an accurate vapor pressure model, the VLE

representation of hydrocarbon-thiol systems is possible,

representing both ideal and non-ideal binaries equally well. The

new mixing rule model is able to predict accurately thiol-

hydrocarbon azeotropes as well as the azeotrope temperature

and composition.

The new Clean Fuels property package methods also include a

binary interaction parameter database regressed for 101 thiol-

hydrocarbon binary pairs. To fill in missing parameters for

systems of binaries forming azeotropes, a newly developed


23/58


2-9

thiol-hydrocarbon binary estimation method is available which

will predict the azeotrope composition and temperature. All the

new methods developed are based on experimental data.

Figure 2.2compares the Clean Fuels property package results

for the system nPropylMercapatn-Hexane with other methods.

As can be seen, the conventional equation of state (EOS)

methods fail while the effect of vapour pressure on the

calculation of the azeotrope for the activity model is highlighted

clearly. Although, the activity model performs fairly well in this

instance, its performance deteriorates with increasing

temperature and pressure. Selecting the correct thermodynamic

model for modeling gasoline fractionation is important.

With a highly accurate VLE thermodynamic model, up to date

binary and pure component databases as well as reliableestimation routines, the simulation of gasoline fractionation

towers can be used to better optimize new designs. For existing

Figure 2.2

VLE Diagram for nPropylMercapatn and Hexane at 1 atm


24/58

2-10 Improve Fractionator Design

2-10

equipment, towers can be rated accurately for performance

changes where ultra low sulphur levels are required.

In the optimization of a gasoline fractionator, two designvariables are considered. Increasing the column number of

trays2and the amount of reflux. Both have the same affect of

reducing the gasoline end point, however as Figure 2.3

illustrates, the effect of increasing the reflux is more dramatic in

controlling the end point temperature of gasoline.

For existing gasoline fractionation towers, increasing reflux may

increase column tray traffic, so tower internals need to be

considered to handle the added capacity.

Figure 2.3: Effect of Fractionator Design on Gasoline End Point


25/58

Clean Fuels Property Package 3-1

3-1

3 Clean Fuels Property

Package

3.1 Introduction................................................................................... 2

3.2 Thermodynamic Model...................................................................2

3.2.1 Estimation Methods .................................................................. 7


26/58

3-2 Introduction

3-2

3.1 IntroductionThe Clean Fuels Property Package is a specially designedproperty package for the accurate VLE representation of thiol-

hydrocarbon containing systems. The Clean Fuels Pkg contains

the latest advances made in the development of cubic equations

of state and mixing rules. A new vapour pressure alpha function

is available that is correlated against DIPPR vapour pressure

data as well as DIPPR pure component properties for 1454

HYSYS components. New databases are available containing

regressed coefficients for 101 thiol-hydrocarbon binary pairs,

and a new proprietary thiol-hydrocarbon estimation method is

able to predict the formation of azeotropes and calculate the

binary parameters from infinite dilution activity coefficient data.

The Clean Fuels Pkg allows User Data to be supplied forazeotropes and infinite dilution activity coefficient data as well

as supporting 49 DIPPR thiol containing components listed in the

table of the sulphur species supported in HYSYS for the Clean

Fuels Property Package in Section 2.1 - Gasoline Sulphur

Species Distribution.

3.2 Thermodynamic ModelSelecting an appropriate thermodynamic model to represent

Clean Fuels processes requires the selection of an appropriatecubic equation of state that will allow better prediction of liquid

densities of mid-range to heavy hydrocarbons and polar

components. Also a highly accurate vapour pressure alpha

function is needed that extrapolates correctly beyond the critical

point. A suitable mixing rule is necessary that can allow

hydrocarbon-hydrocarbon binary pairs to be modelled with the

accuracy of an equation state while able to represent non-ideal

thiol-hydrocarbons as well as an activity model. Finally, the

selection of a suitable thermodynamic model involves choosing

an appropriate activity model that would allow the new mixing

rules to transition the van der Waals one-fluid mixing rules for

hydrocarbon binaries.


27/58


3-3

The Clean Fuels Property Package uses an optimal two-

parameter cubic equation of state TST (Twu-Sim-Tassone)3to

represent Clean Fuels Processes. The TST cubic equation is

represented as follows:

and can be rewritten in the form,

The values of aandbare at the critical temperature and arefound by setting the first and second derivatives of pressure

with respect to volume to zero at the critical point:

where:

c = critical point

The value of Zcfrom the SRK and PR equations are both larger

than 0.3 while Zcfrom the TST equation is slightly below it,

closest to the real one for many substances.

A prerequisite for the accurate VLE representation of thiol-

hydrocarbon systems in the entire composition range is the

accurate calculation of pure component vapour pressures.

(3.1)

(3.2)

(3.3)

(3.4)

(3.5)

P RT

v b-----------

a

v2

2.5bv 1.5b2

+--------------------------------------------=

P RT

v b-----------

a

v 3b+( ) v 0.5b( )---------------------------------------------=

a Tc( ) 0.427481R2

Tc2

Pc=

b 0.086641RTc Pc=

Zc 0.296296=


28/58

3-4 Thermodynamic Model

3-4

You can use the Twu alpha correlation4.

Equation (3.7)has three parameters L, M, and N. These

parameters are unique to each component and are determined

from the regression of DIPPR pure component vapour pressure

data for 1454 components.

The generalized alpha function is used for non-library and

petroleum fractions:

where:

(0)is for =0

(1)is for =1

Each alpha is a function of reduced temperature only.

To model both van der Waals fluids and highly non-ideal

mixtures using the same Gibbs excess energy model we use the

TST Zero-Pressure Mixing Rules3. The zero-pressure mixing

rules for the cubic equation of state mixture a and b parametersare:

(3.6)

(3.7)

(3.8)

(3.9)

bvdwis used for b.

TrN M 1( )

e

L 1 TrNM

( )

=

0( ) 1( ) 0( )( )+=

a*

b* avd w

*

bvd w*

----------- 1

Cv0---------+

A0E

RT-------

A0vd wE

RT-------------- ln

bvd w

b-----------

=

b xixj1

2--- bi bj+( )

j

i

=


29/58


3-5

avdwand bvdware the equation of state a and b parameters

which are evaluated from the van der Waals mixing rules. The

Twu mixing rule given by Equation (3.8)is volume-dependent

through Cv0. Cv0is a function of the reduced liquid volume atzero pressure v0*=v0/b:

Since the excess Helmholtz energy is a weak function of

pressure [5] we assume that the excess Helmholtz energy of the

van der Waals fluid at zero pressure can be approximated by the

excess Helmholtz energy of van der Waals fluid at infinite

pressure:

A new versatile activity model NRTLTST 6is used to describe

both a van der Waals fluid and a highly non-ideal mixture:

When ijand Gijare calculated using the parameters inEquation (3.13)and Equation (3.14), the NRTL equation is

obtained.

(3.10)

(3.11)

(3.12)

(3.13)

Cv01

w u( )-----------------ln

v0*

w+

v0*

u+---------------

vd w

=

A0vd wE

RT--------------

Avd wE

RT--------------- Cv0

avd w*

bvd w*

----------- xiai

*

bi*

-----

i

= =

GE

RT------- xi

i

n

xj

ji

Gji

j

n

xkGki

k

n

-------------------------=

jiAji

T

------=


30/58


3-6

However, Equation (3.12)can also recover the conventionalvan der Waals mixing rules when the following expressions are

used for ijand Gijinstead:

where:

The TST mixing rules in Equation (3.8)are density dependent

through the function Cv0. Because of this density function, the

mixing rule is able to reproduce almost exactly the incorporated

GEmodel. Cv0as defined by Equation (3.10)is calculated from

v0*vdw by solving the equation of state in Equation (3.1)at zero

pressure. This step can cause problems if there is no real root,

which may occur when non-condensable components arepresent, for example. When this occurs, some sort of

extrapolation for v0*must be made. To omit the need for the

calculation of v0*from the equation of state, the zero-pressure

liquid volume of the van der Waals fluid, v0*vdw, is a constant, r:

Substituting Equation (3.18)into Equation (3.10), Equation

(3.10)becomes:

(3.14)

(3.15)

(3.16)

(3.17)

(3.18)

(3.19)

Gji exp ji ji( )=

ji1

2---ij bi=

Gjibj

bi----=

ijCv0

RT---------

ai

bi--------

aj

bj--------

2

2kij

ai

bi--------

aj

bj--------+=

v0vd w*

r=

Cr1

w u( )-----------------ln

r w+

r u+------------

=


31/58


3-7

A universal value of r=1.18 has been determined from

information on the incorporated GEmodel and is recommended

by Twu et al.7for use in the phase equilibrium prediction for all

systems.

3.2.1 Estimation MethodsFor systems containing thiols and hydrocarbons, some

hydrocarbons and petroleum fractions form azeotropes with

thiols. In cases where VLE data is not available for these

systems, reliable estimation methods are necessary to predict

the azeotrope and to calculate the binary interaction

parameters. The Clean Fuels Pkg contains an internal

proprietary estimation routine used to estimate the binary

interaction parameters of thiol and hydrocarbons that formazeotropes. Binary estimation methods have been developed

specifically for the thiols, enthanethiol, 1-propanethiol, 2-

propanethiol, 1-butanethiol, 2-butanethiol, 2-methyl 1-

propanethiol and 2-methyl 2-propanethiol in mixtures of

paraffins and naphthenes, while a generalized estimation

method is available to calculate the binary parameters for all

other thiols. The user is also allowed to enter User applied

azeotrope data or infinite dilution activity coefficient data for

calculation of binary parameters.


32/58


3-8


33/58

Clean Fuels Pkg Extension 4-1

4-1

4 Clean Fuels Pkg

Extension

4.1 Using the Clean Fuels Pkg Extension.............................................. 2

4.1.1 Adding a Clean Fuels Pkg ..........................................................2

4.2 Clean Fuels Pkg Extension User Interface...................................... 3

4.3 Clean Fuels Pkg Property View....................................................... 4

4.3.1 NRTLTST Tab ........................................................................... 4

4.3.2 TST CEOS Tab..........................................................................5


34/58

4-2 Using the Clean Fuels Pkg Extension

4-2

4.1 Using the Clean Fuels

Pkg ExtensionYou can add a Clean Fuels Pkg Extension only if it exists as part

of a HYSYS case. A Property Package Extension that is part of an

existing case can be accessed in the HYSYS Basis Environment.

In the Basis Environment, you can view and adjust the

extension variables as you would any HYSYS Property Package.

Before creating a new Clean Fuels Pkg, the user is required to be

working within a HYSYS case that has a Fluid Package installed.

The Fluid Package must consist of a property package and

associated flowsheet components.

4.1.1 Adding a Clean Fuels PkgTo add a Clean Fuels Pkg to an existing HYSYS case:

1. From the Simulation Basis Manager, click on the Fluid Pkgstab.

2. Click the Addbutton to add a Clean Fuels Pkg. The FluidPackage property view appears.

3. In the Property Pkg Filter group, click the MiscellaneousTypesradio button.

Refer to Chapter 2 -Fluid Packageof theHYSYSSimulationBasis guide for moreinformation on the HYSYSProperty Package.
http://../HYSYS/Manual%20Source/Simulation%20Basis/Fluid%20Pack/HYSYSBasisFluidPkg.pdfhttp://../HYSYS/Manual%20Source/Simulation%20Basis/Fluid%20Pack/HYSYSBasisFluidPkg.pdfhttp://../HYSYS/Manual%20Source/Simulation%20Basis/Fluid%20Pack/HYSYSBasisFluidPkg.pdfhttp://../HYSYS/Manual%20Source/Simulation%20Basis/Fluid%20Pack/HYSYSBasisFluidPkg.pdf


35/58


4-3

4. From the available property packages list select Clean FuelsPkg.

4.2 Clean Fuels PkgExtension UserInterface

The Clean Fuels Pkg Extension user interface is completely

integrated into the HYSYS working environment and conforms toall HYSYS usage conventions for operations and data entry. If

you are an experienced user of HYSYS, you will already be

familiar with all of the features of the Property Package user

interface. If you are a new user, begin by reviewing the HYSYS

User Guideto familiarize yourself with HYSYS before using the

Clean Fuels Pkg Extension.

Figure 4.1

The View PropertyPackage button allows youto view the Clean Fuels Pkgparameters.

The Clean Fuels Pkgparameters are shown onthe Clean Fuels Pkgproperty view.


36/58

4-4 Clean Fuels Pkg Property View

4-4

4.3 Clean Fuels Pkg

Property ViewLike all HYSYS property views, the Clean Fuels Pkg property

view allows you access to all information associated with a

particular item, such as the interaction parameter pages. You

can specify the binary interaction parameters or regress User

data on the Clean Fuels Pkg property view.

The Clean Fuels Pkg property view has two tabs (NRTLTST and

TST CEOS), and on each tab are groups of related parameters.

4.3.1 NRTLTST TabThe NRTLTSTS tab as shown in Figure 4.2contains the binary

parameters for the activity coefficient model NRTLTST (NRTL-

Twu-Sim-Tassone) used in the TST (Twu-Sim-Tassone) AEMixing

Rules. This tab allows the user to view the binary parameters forthe activity model and to fill-in binary parameters not present in

the database or not calculated from the internal estimation

Figure 4.2


37/58


4-5

methods.

User DataThe User Data button allows the user to provide either infinite

dilution activity coefficient data or azeotrope data per binary in

the calculation of interaction parameters for azeotrope

prediction of thiol-hydrocarbon binaries.

4.3.2 TST CEOS TabThe TST CEOS tab contains the binary parameters for the TST

(Twu-Sim-Tassone) cubic equation of state (CEOS).

It is recommended that unknown parameters be filled-in atall times using the UNIFAC VLE fill-in method.

Figure 4.3


38/58

4-6 Clean Fuels Pkg Property View

4-6

The Twu Alpha Params button allows the user access to the Twu

vapor pressure alpha function parameters L, M and N, as well as

access to the DIPPR pure component properties Tc and Pc.

Figure 4.4


39/58

Clean Fuels Pkg Tutorial 5-1

5-1

5 Clean Fuels Pkg

Tutorial

5.1 Introduction................................................................................... 2

5.2 Flowsheet Setup ............................................................................ 3

5.3 Modeling the Gasoline Fractionator.............................................. 10

5.3.1 Exercises .............................................................................. 14

5.4 Plot Utility .................................................................................... 15


40/58

5-2 Introduction

5-2

5.1 IntroductionThe following example demonstrates how to use the Clean FuelsPkg to model a gasoline fractionator. In this example, a light/

medium gasoline is fractionated in a gas plant column. The

amount of sulphur is calculated in the light gasoline and the

gasoline endpoint is set to 150F for design. The case willconsist of a FCC Gasoline feed stream to the tower and two

outlet streams, a light gasoline product stream and an

intermediate naphtha which is sent to an upstream hydrotreater

for further treating. The design objective is to maximize the

yield of light gasoline since hydrotreating of gasoline results in

severe octane loss.

Figure 5.1


41/58


5-3

5.2 Flowsheet SetupBefore working with the Clean Fuels Pkg Extension, you mustfirst create a HYSYS case.

1. In the Simulation Basis Manager, create a fluid packageusing the Clean Fuels Pkg. Add the HYSYS Thiol librarycomponents 2C3Mercaptan, nPMercaptan and Thiophene.

Add the paraffins and olefins as shown in the table below,

and then close the Component List property view.

2. Click on the Oil Managertab of the Simulation BasisManager to install an oil with the TBP curve (light ends are

added in the main flowsheet).

Property Package Components

Clean Fuels Pkg 2C3Mercaptan, nPMercaptan, Thiophene

Component Name

i-Butane

i-Butene

n-Butane

i-Pentane

1-Pentene

2M-13-C4==

Cyclopentene

3M1C5=

Cyclopentane

23-Mbutane

2-Mpentane

2M1C5=

1-Hexene

n-Hexane

If you are unable to find the component using the defaultSim Name option on the Component List property view, clickon the Full Name/Synonym radio button. Then type thecomponent name in the Match field.

For more information onadding librarycomponents, refer toChapter 1 -Componentsin theHYSYS SimulationBasis guide.
http://../HYSYS/Manual%20Source/Simulation%20Basis/Components/HYSYSBasis%20Components.pdfhttp://../HYSYS/Manual%20Source/Simulation%20Basis/Components/HYSYSBasis%20Components.pdfhttp://../HYSYS/Manual%20Source/Simulation%20Basis/Components/HYSYSBasis%20Components.pdfhttp://../HYSYS/Manual%20Source/Simulation%20Basis/Components/HYSYSBasis%20Components.pdf


42/58

5-4 Flowsheet Setup

5-4

3. Click the Enter Oil Environmentbutton. The OilCharacterization property view appears.

4. Click the Addbutton. The Assay property view appears.

5. In the Namefield, type FCC Gas Oil.

6. From the Assay Data Typedrop-down list on the Input

Datatab, select TBP.

Figure 5.2

Figure 5.3


43/58


5-5

7. In the Input Data group, click on the Edit Assaybutton. TheAssay Input Table property view appears.

8. Add the assay input data as shown in the table below.

Figure 5.4

Assay Percent [%] Temperature [F]

0.0 108.6

5.0 167.3

15.0 190.2

20.0 201.4

25.0 213.6

30.0 226.335.0 239.3

40.0 252.7

45.0 266.2

50.0 279.5

55.0 292.4

60.0 305.5

75.0 348.3

90.0 407.9

95.0 425.5

98.0 458.3

100.0 490.2


44/58

5-6 Flowsheet Setup

5-6

9. After you have entered the assay input data, click the OKbutton to return to the Assay property view.

10.Close the Assay property view to return to the Oil Managerproperty view.

11.Click on the Cut/Blendtab to create a Blend object.

12.Click the Addbutton. The Blend property view appears.

13. In the Namefield, type FCC Gas Oil.

Figure 5.5

Figure 5.6


45/58


5-7

14.From the Cut Option Selectiondrop-down list of theDatatab, select Auto Cut.

15.Click the Add button to select the assay.

16.Enter the data as shown in the table below.

17.Close the Blend property view to return to the Oil Managerproperty view.

18.Click on the Install Oiltab, and in the Stream Namecolumn type FCC Gas Oil as shown in the figure below.

Figure 5.7

Flow Units Flow Rate

Mass 364008 lb/hr

The default Flow Unit is Liquid Volume ensure that you haveselected Mass from the drop-down list before specifying theflow rate.

Figure 5.8


46/58

5-8 Flowsheet Setup

5-8

19.Click the Calculate Allbutton to calculate the all the assaysand blends. Then click the Return to Basis Environmentbutton. The Simulation Basis Manager appears.

20.Click on the Fluid Pkgstab, and then click the View button.

21. From Fluid Package property view, click the View PropertyPackagebutton. The Clean Fuels Pkg property viewappears.

Click the Unknowns Only button to specify the missing

Binary Interaction Parameters (BIPs) using the UNIFAC VLE

methods. Ensure that you have selected the UNIFAC VLE

radio button.

22.Close the Clean Fuels Pkg property view and the FluidPackage property view.

23. From the Simulation Basis Manager, click the EnterSimulation Environment to build your flowsheet.

Ensure that you have selected the Clean Fuels Pkg in theCurrent Fluid Packages list.

Figure 5.9

For more information onadding a stream, refer toChapter 12 - Streamsinthe HYSYS Operations

Guide.
http://../HYSYS/Manual%20Source/Operations%20Guide/Streams/Streams.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Streams/Streams.pdf


47/58


5-9

You can also press CTRL Lto leave the Basis Environment.

24.Create two streams named Sulphur Spikeand Light Endsin the Simulation Environment with the following streamconditions and composition.

Ensure that you have the Mass Flow radio button selected in

the Composition Basis group of the Input Composition fromStream property view before specifying the streamcomposition.

Conditions

Stream Name Sulphur Spike

Temperature [F] 100

Pressure [psia] 114.6

Mass Flow [lb/hr] 219.6

Composition Mass Flow [lb/hr]

2C3Mercaptan 60.1

nPMercaptan 53.5

Thiophene 106.0

Conditions

Stream Name Light Ends

Temperature [F] 100


Mass Flow [lb/hr] 1.705E+005

Composition Mass Flow [lb/hr]

i-Butane 392.2

i-Butene 13543.9

n-Butane 2318.5

i-Pentane 40094.1

1-Pentene 49783.6

2M-13-C4== 1475.2

Cyclopentene 2345.5

3M1C5= 2162.2

Cyclopentane 1138.2

23-Mbutane 5138.8

2-Mpentane 30575.8

2M1C5= 3221.3


48/58

5-10 Modeling the Gasoline Fractionator

5-10

25.Define the FCC Gas Oil stream conditions as shown in thetable below.

26. Add a Mixer with the outlet stream named FCC Gasoline,and feed streams Sulphur Spike, Light Endsand FCC Gas

Oil.

27.Add a shell and tube Heat Exchanger with a 10 psi pressuredrop on both shell and tube sides.

The Shell side of the heat exchanger will heat the feed to the

column while the tube side cools the column bottoms

product.

28. In the Heat Exchanger property view, name the tube sidefeed Medium Gasolineand the outlet tube side toHydrotreater.

29.Specify the shell side feed FCC Gasoline, and name theoutlet shell side Feed to Fractionator.

30.Specify a stream temperature of 223Ffor Feed toFractionator.

31. In the Parameters page of the Heat Exchanger propertyview, change the Heat Exchanger Model to ExchangerDesign (Weighted).

5.3 Modeling the GasolineFractionator

The Gasoline fractionator is modeled as a distillation column inHYSYS using a Partial Reflux Condenser.

1-Hexene 12306.8

n-Hexane 6004.2

Conditions

Temperature [F] 100


Mass Flow [lb/hr] 364008.7

Liq. Vol Flow [barrel/day] 32784.7

Conditions

For more information onadding a Mixer, refer toSection 6.3 - Mixerinthe HYSYS OperationsGuide.

For more information onadding a Heat Exchanger,refer to Section 4.4 -Heat Exchangerin theHYSYS OperationsGuide.
http://../HYSYS/Manual%20Source/Operations%20Guide/Piping%20Equipment/PipingEquipment.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Heat%20Transfer%20Equipment/HeatTransferEquipment.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Heat%20Transfer%20Equipment/HeatTransferEquipment.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Heat%20Transfer%20Equipment/HeatTransferEquipment.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Heat%20Transfer%20Equipment/HeatTransferEquipment.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Piping%20Equipment/PipingEquipment.pdf


49/58


5-11

1. Add a distillation column with a partial condenser.

2. In the Connectionspage, name the liquid distillate LightGasoline, the overhead vapor draw as Vent and the

bottoms liquid as Medium Gasoline. Cond-qand Reb-qare the condenser and reboiler heat loads respectively.

3. The tower has 20theoretical stages, and the feed to thetower enters on Stage13.

4. The pressure in the condenser is set at 240 kPa, thepressure drop across the condenser is 55.16 kPa andthebottom reboiler pressure is at 350 kPa.

5. On theMonitorpage, enter a Reflux Ratio estimate of 1.0and turn-off this specification. Set the Ovhd Vapor Rate to0.0 MMSCFD, the distillate rate to 1.213e+004 barrel/day (Volume).

Figure 5.10

For more information on adistillation column, referto Chapter 2 - Column

Operations in theHYSYS OperationsGuide.
http://../HYSYS/Manual%20Source/Operations%20Guide/Column/Column.pdfhttp://../HYSYS/Manual%20Source/Operations%20Guide/Column/Column.pdf


50/58


5-12

6. Add a TBP End Point Volume Percent column specification forLiquid Distillate at 150F (65.56C).

The figure below shows the Monitor page after adding a TBP

End Point Volume Percent column.

7. Click on the Parameters tab, and enter a top stagetemperature estimate of 140Fand a Tray 1 temperature

estimate of 180F. Enter a bottoms reboiler temperatureestimate of 300F.

Figure 5.11

Figure 5.12


51/58


5-13

8. Run the column and examine the column performance.

Before running the column, ensure that the outlet streams

are updated. Select the Update Outlets checkbox for thecolumn to automatically update the outlet streams. Bydefault the Update Outlets checkbox is selected.

Figure 5.13

Figure 5.14


52/58


5-14

5.3.1 Exercises1. Add a HYSYS Spreadsheet (Sulphur Calculations) to

calculate the total sulphur content in ppm wt of lightgasoline.

Spreadsheet Connections

Cell Object Variable

D2 Light Gasoline Comp Mass Flow, 2C3Mercaptan

D3 Light Gasoline Comp Mass Flow, nPMercaptan

D4 Light Gasoline Comp Mass Flow, Thiophene

B6 Light Gasoline Mass Flow

B7 Fractionator Spec Value TBP End Point

Figure 5.15


53/58


5-15

2. Find the Light Naphtha TBP End Point that corresponds toless than 10 ppm wt and 1 ppm wt Thiophene Sulphur.

5.4 Plot Utility1. Begin a new HYSYS case, add a Fluid Package using the

Clean Fuels Pkg and add the two components 1-Propanethioland n-Hexane. Enter the Simulation Environment.

2. Open the Excel Spreadsheet Txy Plot Utility, and connectto HYSYS.

3. Plot a Txy Diagram for system 1-Propanethiol-n-Hexane at

101.325kPa.

4. Find the azeotrope temperature and composition.

Ans. Experimental Data. (1PRSH) xazeo=0.5570,

Tazeo=147.83F.

Figure 5.16


54/58

5-16 Plot Utility

5-16

Figure 5.17


55/58

References A-1

A-1

A References

1 Halbert, T. R., Brignac, G. B., Greeley, J. P., Demmin, R. A. and

Roundtree, E. M., Getting Sulfur on Target, Hydrocarbon

Engineering, June 2000, pp.1-5.

2 Golden, S. W., Hanson, D. W. and Fulton, S. A., Use Better

Fractionation to Manage Gasoline Sulphur Concentration,

Hydrocarbon Processing, February 2002, pp. 67-72.

3 Twu, C.H., Sim, W.D. and Tassone, V., A versatile liquid activity

model for SRK, PR and a new cubic equation-of-state TST, Fluid

Phase Equilibria 194-197, 2002, pp. 385-399.

4 Twu, C.H., Bluck, D., Cunningham, J.R. and Coon, J.E., Fluid PhaseEquilibria, 69, 1991, pp. 33-50.

5 Wong, S.H. and Sandler,S.I., 1992, AIChE J., 38, 1992, pp. 671-680.

6 Twu, C.H., Wayne, D., and Tassone, V., Liquid Activity Coefficient

Model for CEOS/AE Mixing Rules Fluid Phase Equilibria, 183-184,

2001, pp. 65-74.

7 Twu, C.H., Coon, J.E. and Bluck, D., Fluid Phase Equilibria, 150-151,

1998, pp. 181-189.


56/58

A-2

A-2


57/58

I-1

IndexC

Clean Fuels Pkgadding 4-2

NRTLTST tab 4-4property view 4-4

TST CEOS tab 4-5tutorial 5-15-15

Clean Fuels Pkg Extension

user interface 4-3using 4-2

E

Estimation Methods 3-7

F

Fractionator designthrough accurate VLE models 2-82-10

G

Gasoline Sulphur species distribution 2-22-4

L

Light/Medium Gasoline fractionation 2-52-7

M

Modeling the Gasoline Fractionator 5-10

N

NRTLTST tab 4-4User Data 4-5

P

Plot Utility 5-15

R

Requirementssystem 4-2

T

Thermodynamic Model 3-23-7estimation methods 3-7

TST CEOS tab 4-5

U

User Data 4-5User Interface



58/58

aspenhysyscleanfuels2006 5 usr

Documents