Using Accurate Models for Process Modeling. Olivier Baudouin (ProSim) Stéphane Déchelotte Alain Vacher

Transcription

1 Usng Accurate Models for Process Modelng Olver Baudoun (ProSm) Stéphane Déchelotte Alan Vacher

2 Outlne What are Steady State Process Smulaton Software? Importance of Thermodynamcs nsde Smulaton Software? Approaches used for Flud Phase Equlbra Homogeneous Approach (Equatons of State) Heterogeneous Approach (G E Models) New Mxng Rules for Equatons of State (EOS / G E ) SAFT Equatons of State Specfc Models Descrpton of a Thermophyscal Propertes Calculaton Server

3 Steady-State Process Smulator Tools performng rgorous mass and energy balances for all the operatng unts of a contnuous process n steady state operaton Calculaton of all process streams characterstcs (flowrate, temperature, pressure, composton, physcal propertes,...) Calculaton of performance of equpments Calculaton of all process data requred for equpment szng Calculaton of data requred for energetc analyss of a process (Pnch )

4 Typcal Process Industres Served Chemcal & Petrochemcal Processng (ammona and fertlzer plants, olefns, ethylene crackers, polymers, fne & specalty chemcals, norganc chemcals, ntermedates, solvent recovery, ) Ol & gas producton (Offshore platforms, on-shore felds and facltes, LNG plants and termnals, gas dehydraton, gas sweetenng, NGL plants, gas processng, ppelnes, ) Petroleum refnng (Crude/vacuum dstllaton, hydrocrackng, FCCU, somerzaton, alkylaton, hydrotreaters, sulfur recovery, reformers, cokers, lube processng ) Energy (Combned cycle/cogeneraton, nuclear, coal processng, gasfcaton combned cycles, water and utltes, ) and many other felds (Ar separaton, carbon capture & storage, bo-fuels, pharmaceutcals, pulp & paper, bochemcals, food and food ntermedates, ) Operatng companes as well as E&C (Engneerng & Constructon) companes n these felds For conceptual desgn, optmzaton, and performance montorng

5 Useful Throughout the Process Lfecycle R&D, lab. Conceptual development Process Engneerng Detaled Engneerng Constructon & Commssonng Operatons from expermental data regresson to optmzaton of a complete process unt or plant

6 Example of a Flash-Unt (wthout chemcal reacton) Feed P T Vapor Flowrate: V Composton: y Enthalpy: H Data: F, z, HF Parameters: P, T, Q Varables: V, L, y, x, H, h Equatons Flowrate: F Composton: z Enthalpy: HF Q Lqud Flowrate: L Composton: x Enthalpy: h Global mass balance: L + V - F = Partal mass balances: L. x + V. y - F. z = Enthalpy balance: L. h(t,p,x) + V. H(T,P,y) - F. HF(T,P,z) - Q = Thermodynamc equlbrum relatons: f v (T,P,y) = f L (T,P,x) or y = K (T,P,x,y). x Constrants: S x = 1 S y = 1 S z = 1 Thermophyscal propertes Numercal algorthms Chemcal reacton models Unt operaton models

7 Software Archtecture Unt operaton models Thermophyscal calculaton server

8 Concepton of a Dstllaton Column Influence of Relatve Volatlty Error % on the number of theoretcal stages requred a = 1.5 A+B? A B 3 25 a = 1.2 a = a = 4 5 a = Error % on the relatve volatlty (a)

9 Relatve volatlty wrt H 2 O Concepton of a dstllaton column Influence of relatve volatlty Relatve volatlty of H 2 O/x (x=hdo, HTO, D 2 O, DTO, T 2 O) W.A. Van Hook, Vapor Pressures of the Isotopc Waters and Ices, The Journal of Physcal Chemstry, 1968, Vol. 72, No 4, p HDO (model) HTO (model) 1.2 D2O (model) DTO (model) T2O (model) An error on thermodynamc model for flud phase equlbra can lead to a too bg column (several meters of packng n excess) or to a too small column (specfcatons wll not be reached) HDO (Van Hook) HTO (Van Hook) D2O (Van Hook) DTO (Van Hook) T2O (Van Hook) Temperature (K)

10 Data Requred For Accurate Results Process smulaton Pure component propertes (Tc, Pc,, P, ) Bnary propertes (VLE, LLE, excess propertes, ) Accuracy of results Basc concept The behavor of a mult-components system can be deducted from the knowledge of the behavor of the pure substances and the bnares Only expermental data of pure substances and bnary systems are requred

11 Smuls Thermodynamcs Software component for computng thermophyscal propertes and phase equlbra on pure substances or mxtures Smuls Thermodynamcs n MS-Excel, MATLAB or other applcatons

12 Smuls Thermodynamcs Thermodynamc Functons To compute thermo-physcal propertes (Transport, Compressblty, Thermodynamc, Non-deal and ther dervatves)

13 Smuls Thermodynamcs Thermodynamc Functons Flashes (LV, LLV, LL,...) To compute phase equlbra (Vapor-lqud, lqud-lqud, vapor-lqud-lqud flashes)

14 Smuls Thermodynamcs Databases (pure, BIP) Thermodynamc Functons Flashes (LV, LLV, LL,...)

15 Pure Compound Propertes Suppled wth a database of over 2 compounds based on AIChE's DIPPR database (publc release 25) 125 constant propertes (molar weght, crtcal temperature, ) 16 temperature dependant propertes (Cp, P,, Hvap ) Optonally the last publc verson of the DIPPR database can be suppled All propertes can be edted, modfed, plotted, Pure compound propertes can be estmated Or regressed from expermental data

16 Smuls Thermodynamcs Databases (pure, BIP) Thermodynamc Functons Thermodynamc Modelss Flashes (LV, LLV, LL,...)

17 A Range of Thermodynamc Models Equatons of State Soave-Redlch-Kwong (SRK) Peng-Robnson (PR) Predctve Peng-Robnson (PPR78) Lee-Kesler-Plöcker (LKP) BWRS Nakamura NRTL-PR PPC-SAFT etc Actvty coeffcents models NRTL UNIQUAC UNIFACs (Larsen, Dortmund, ) Wlson etc Combned approach models MHV2 MHV1 PSRK etc Specfc systems Pure Water (NBS/NRC steam tables - IAPS,1984) Chao-Seader, Grayson-Streed Sour-Water Carboxylc acds Formaldehyde etc Electrolytes Edwards UNIQUAC electrolyte ULPDHS Amnes etc

18 Equaton of State Approach Equatons of State derved from van der Waals Theory (1873) 2 V a b V RT P = Repulsve term (volume of molecules, b) Attractve term (nternal pressure, a) P P T 2 2 T = = At crtcal pont (T=T c, P=P c ) : 2a b RT P 3 c 2 c c T = = 6a b 2RT P 4 c 3 c c T 2 2 = = C 2 C 2 P T R a = C C P RT 8 1 b = 8 3 Z C = 2 C C C C V a b V RT P =

19 Equaton of State Approach Redlch and Kwong (1949) : P = RT V b V aa V b a = 1 T Soave (1972) : RT P = V b V a = aa V b.5 1 m 1 2 T r Peng-Robnson (1976) : a = RT P = V b V 2 aa 2 2 bv b T.5 2 Improvements: new alpha functons (Boston-Mathas, Mathas-Coppeman, Twu-Bluck-Cunnngham-Coon ), volume translaton (Peneloux) r

20 Equaton of State Approach Some other Classcal Equatons of State: Z - Z Z Z r r = Lee-Kesler (1975) : Benedct-Webb-Rubbn (194) : = = V - exp V V T c V D V C V B 1 T P V Z 2 r 2 r 2 r 3 r 4 5 r 2 r r r r r 2 e 1 T T h T g T c T f T e T d a T f T e T d a brt T E T D T C A RT B RT P 2 3 S E 3 2 A a =

21 Equaton of State Approach Equlbrum constant (vapor-lqud): K T, P, x, y = L V T, P, x T, P, y Applcaton range: «Systems composed of normal gases, rare gases, ntrogen, oxygen, carbon monoxde, hydrocarbons and some hydrocarbons dervatves. Carbon doxde, hydrogen sulfde, hydrogen and wth some lmts, some lght polar substances can be ncluded». L. Oellrch, U. Plöcker, J.M. Prausntz and H. Knapp, «Equaton of State Methods for Computng Phase Equlbra and Enthalpes, Int. Chem. Eng., 21, 1, pp 1-16 (1981)

22 Methane Pressure (atm) Equaton of State Approach Phase Envelope of a Methane Benzene (,25-,75 mol/mol) mxture mole % Methane + 75 mole % Benzene Methane vapor pressure Benzene Vapor pressure Methane Crtcal Pont Benzene Crtcal Pont Mxture Dew Curve Mxture Bubble Curve Mxture Crtcal Pont Benzene Temperature ( C)

23 Pressure (bar) Equaton of State Approach Phase envelopes for mxtures of mole % C1 and,1 mole % of nc9, dmethylcyclohexane and ethylbenzene wth NRTL-PR EoS 8 n-nonane Ethyl benzene Dmethylcyclohexane Temperatute ( C)

24 Acetone vapor mole fracton Equaton of State Approach Vapor - Lqud equlbrum curve of Acetone - Water 76 mmhg Othmer, D.F., M. M. Chdgar, Sh. L. Levy, Ind. Eng. Chem., 44, 1872 (1952) Exp. SRK Acetone lqud mole fracton

25 Heterogeneous Approach (-) Based on an actvty coeffcents model n order to take care about the non dealty of the lqud phase: Margules Scatchard Hldebrand (Regular solutons) Wlson NRTL Unquac UNIFAC Models And based on a equaton of state usable for vapor phase: Ideal gas Soave Redlch Kwong Peng Robnson Lee Kessler Plöcker

26 Acetone vapor mole fracton Heterogeneous Approach (-) Vapor - Lqud equlbrum curve of Acetone - Water 76 mmhg Othmer, D.F., M. M. Chdgar, Sh. L. Levy, Ind. Eng. Chem., 44, 1872 (1952) Exp. NRTL SRK Acetone lqud mole fracton

27 Heterogeneous Approach (-) Vapor Phase: Lqud phase: f f V L f V T, P, y = T, P, y.y. P L T, P, x = T, x.x.f T, P L L V v T,P = T, P (T ) P T exp P P T RT Equlbrum constant: K T, P, x, y = L T, X f T, P V T, P, y P Applcaton doman: Chemcal systems where complex chemcal or polar nteractons take place; low pressure and temperature (far above the crtcal pont)

28 Equaton of State Approach wth Complex Mxng Rules (EoS/G E ) Use of a unque equaton of state for the whole flud zone ncludng sophstcated mxng rules based on actvty coeffcent models: Equatons of state (cubc) Soave Redlch Kwong Peng Robnson Actvty coeffcents models Wlson NRTL UNIQUAC UNIFACs Mxng rules MHV1 MHV2 PSRK f H T, P, z = T, P, z * * T, P, z = z H T, P = H - H z P T, P

29 Equaton of State Approach wth Complex Mxng Rules (EoS/G E ) Acetone vapour molar fracton Vapor - Lqud equlbrum curve of Acetone - Water 76 mmhg Othmer, D.F., M. M. Chdgar, Sh. L. Levy, Ind. Eng. Chem., 44, 1872 (1952) Exp. NRTL SRK_MHV2_NRTL Acetone lqud molar fracton

30 Pressure (Ps) Equaton of State Approach wth Complex Mxng Rules (EoS/G E ) Acetone - Water SRK - MHV2 MR - NRTL Grswold, J. Wong, S.Y, Chem. Eng. Prog. Symp. Seres, 48, N 3 (1952) Bubble curve at 15 C Dew curve at 15 C Bubble curve at 2 C Dew curve at 2 C Bubble curve 25 C Dew curve at 25 C Expermental bubble curves Expermental dew curves Acetone molar fracton

31 log P [bar] Equaton of State Approach wth Complex Mxng Rules (EoS/G E ) 2,5 Ethanol (1) / water(2) Comparson of MHV2 n SmulsThermodynamcs TM wth expermental results Barr-Davd,F. and B.F.Dodge, J.Chem.Eng.Data, 4, 17 (1959) 2 3 C 25 C 1,5 2 C 1 15 C,5,1,2,3,4,5,6,7,8,9 1 x1, y1

32 PPC-SAFT Statstcal Assocatng Flud Theory (Chapman et al. 199) Z resdual = Z SAFT 1 = m (Z rep + Z dsp ) + Z chan + Z assoc + Polar extenson (Z pol ) µ or Q Z rep = Z réference HS = f(, ε) Dspersve-attractve f(, ε) Gubbns et Twu 1978 ε Chan f (m,) ln Z chan = ( 1 - m ) HS g ( d ) ρ Assocaton assoc, ε assooc assoc Z = ρ A 1 X A 1 2 A X ρ, X A = f ( assoc ε assooc ) µ, Q Modeled as a chan of m sphercal segments assoc ε assooc Assocaton stes

33 Pressure, MPa PPC-SAFT VLE of Hydrogen - Methane system exp [ K] exp [ K] exp [ K] exp [ K] exp [ K] exp [ K] exp [123.5 K] PPC-SAFT [ K] PPC-SAFT [ K] PPC-SAFT [ K] PPC-SAFT [ K] PPC-SAFT [ K] PPC-SAFT [ K] PPC-SAFT [123.5 K] mole fracton Hydrogen

34 P, atm PPC-SAFT VLE of Hydrogen - Toluene exp [188.7 C] PPR78 [188.7 C] exp [229 C] PPR78 [229 C] exp [269 C] PPR78 [269 C] exp [32 C] PPR78 [32 C] mole fracton Hydrogen

35 P / bar P / bar PPC-SAFT 2 VLE of polystyrene (PS) - ethylbenzene mxture (PS: M = 93 kg/mol) 1,5 1 T=14 C T=16 C Exp. Data (T=14 C) Exp. Data (T=16 C),5,1,2,3,4,5,6,7,8,9 1 w PS 2,5 VLE of polystyrene (PS) - monochlorobenzene mxture (PS: M = 93 kg/mol) 2 GROSS J., SADOWSKI G., Modelng Polymer Systems Usng the Perturbed-Chan Statstcal Assocatng Flud Theory Equaton of State, Ind. Eng. Chem. Res., 41, (22) 1,5 1,5 T=14 C T=16 C Exp. Data (T=14 C) Exp. Data (T=16 C),1,2,3,4,5,6,7,8,9 1 w PS

36 Temperature (K) PPC-SAFT VLLE of Water - 1-Butanol mxture at atmospherc pressure Exp. Bubble Exp. Dew Exp. LLE PPC-SAFT x, y 1-butanol

37 Temperature (K) PPC-SAFT VLLE of Methanol - n-heptane mxture at atmospherc pressure LLE data VLE data PPC-SAFT x, y Methanol

38 HNO3 n vapour, wt fr. Specfc models: Electrolytes H 2 O-HNO 3 : vapour-lqud composton dagram on bnary bass wt% H2SO4 n lqud (calc) 7 wt% H2SO4 n lqu (calc) 2 wt% H2SO4 n lqud (calc) 37 wt% H2SO4 n lqud (calc) 5 wt% H2SO4 n lqud (calc) 7 wt% H2SO4 n lqud (calc) 8 wt% H2SO4 n lqud (calc) wt% H2SO4 n lqud (exp) 7 wt% H2SO4 n lqud (exp) 2 wt% H2SO4 n lqud (exp) 37 wt% H2SO4 n lqud (exp) 5 wt% H2SO4 n lqud (exp) 7 wt% H2SO4 n lqud (exp) 8 wt% H2SO4 n lqud (exp) HNO3 (H2SO4 free) n lqud, wt fr.

39 Na 2 SO 4 n lqud phase (g / 1 g of water) Specfc models: Electrolytes Solublty of Sodum Sulfate n water wth respect to temperature Smulaton Exp Temperature ( C)

40 (y /x) FA / mol.mol -1 x / mol.mol -1 Specfc Models: Reactve Systems Partton coeffcent of formaldehyde at 333K and 383 K and ξ FA =.1 g.g -1 ( 383 K, 333 K). Concentraton of hemformal (HF) and poly(oxymethylene) hemformals HF 2 and HF 3 n chemcal equlbra at 276 K. 2,6 HF 1,5,4 1,2,5 HF 2 HF 3,25,5,75 1 x * ME / mol.mol -1 Partton coeffcent of FA n the FA-water-methanol system,1,2,3,4,5 x FA / mol.mol -1 Concentraton of HF, HF2 and HF3 n chemcal equlbra at 276 K

41 Temperature ( C) Mole fracton (y1) Vapor mole fracton [Y1] Specfc Models: Reactve Systems WATER (1) / FORMIC ACID (2) - Comparsons between expermental / calculated equlbrum data, pressure = 1 atm 1,9,8,7,6 [RIC6] [MEL56] [CON6] Calc. Water (1) / Formc acd (2) - Azeotropc data: Comparson expermental data / smulaton,5,4 16,8,3 14,7,2 12,6,1 1,5 8,4,2,4,6,8 1 Lqud mole fracton [X1] Azeotrope temperature [GME4] Smulaton Azeotrope composton [GME4] Smulaton,3,2,1, Pressure (kpa)

42 Smuls Thermodynamcs Compounds selecton (from databases, modfcatons, comparsons ) Graphcal User Interface Confguraton of the property model Databases (pure, BIP) Thermodynamc Functons Thermodynamc Modelss Flashes (LV, LLV, LL,...)

43 Smuls Thermodynamcs Graphcal User Interface Databases (pure, BIP) Set of Servces Thermodynamc Functons Thermodynamc Modelss Flashes (LV, LLV, LL,...)

44 A Range of Servces Avalable An nteractve calculaton servce Graphcal dsplay of propertes on temperature, pressure or composton ranges Calculaton of petroleum fractons propertes Management of group contrbuton predctve models Estmaton of pure component propertes Data regresson of pure components expermental propertes Unt conversons management tool etc Provde user wth qute all tools requred for thermodynamcs analyss

45 Smuls Thermodynamcs Graphcal User Interface Databases (BIP, Compounds) Thermodynamc functons Set of servces Thermodynamc Models Smuls Thermodynamcs Flashs (LV, LLV, LL,...)

46 Smuls Thermodynamcs Can Be Used n a Number of Ways ProSm Software Sute MS-Excel Add-In Smuls MATLAB Toolbox Thermodynamcs CAPE- OPEN "plug" Modelng tool mplementng CO Thermo Socket Aspen Plus, ProII, Aspen HYSYS, HTRI, gproms Export Usng Smuls Thermodynamcs, fles A.P.I. thermodynamc calculaton Tabulated results to : consstency between software s automatcally ensured MS-Excel Aspen TASC (PSF fle) OLGA (PVT fle) Your software (C++, VB, FORTRAN, )

47 Thank you for your attenton! Usng Accurate Models for Process Modellng Olver Baudoun (ProSm) Stéphane Déchelotte Alan Vacher

48 Equaton of State Approach wth Complex Mxng Rules (EoS/G E ) Huron Vdal (Reference state: nfnte pressure) Huron Vdal Modfed by Mchelsen (Reference state: null pressure) ex Ln x - Ln RT G = * e e ex b x b C x T, G b a x b a mod G G b V P = = e ex mod G G P MHV2 b b Ln x RT x, T, P G x - q x - q e = = a a a a MHV1,PSRK b b Ln x RT x, P T, G q 1 x e 1 = a = a

49 A Range of Servces Avalable An nteractve calculaton servce

50 A Range of Servces Avalable An nteractve calculaton servce Graphcal dsplay of propertes on temperature, pressure or composton ranges

51 A Range of Servces Avalable An nteractve calculaton servce Graphcal dsplay of propertes on temperature, pressure or composton ranges Calculaton of petroleum fractons propertes D 2887 Smulated dstllaton Results of ASTM D86 dstllaton ASTM D86 corrected Smulaton results TBP at 76 mmhg Set of components, weght composton ASTM D116 at low pressure TBP at 1 mmhg Propertes estmaton ASTM D116 at 76 mmhg ASTM D116 at 1 mmhg

52 A Range of Servces Avalable An nteractve calculaton servce Graphcal dsplay of propertes on temperature, pressure or composton ranges Calculaton of petroleum fractons propertes Management of group contrbuton methods versons Several versons are supported: UNIFAC orgnal UNIFAC (Dortmund) modfed UNIFAC (Dortmund) LL UNIFAC (Lyngby) modfed Larsen UNIFAC formaldehyde PPR78 NRTL-PR A group contrbuton models edtor s suppled

53 A Range of Servces Avalable An nteractve calculaton servce Graphcal dsplay of propertes on temperature, pressure or composton ranges Calculaton of petroleum fractons propertes Management of UNIFAC versons Estmaton of pure component propertes Data regresson of pure components expermental propertes Unt conversons management tool etc Provde user wth qute all tools requred for thermodynamcs analyss

54 Smuls Thermodynamcs Can Be Used n ProSm Software Sute Snce Smuls Thermodynamcs s a software component t must be embedded n another applcaton ProSm Software Sute Smuls Thermodynamcs Smuls Thermodynamcs s the thermodynamc "heart" of all ProSm software sute

55 Smuls Thermodynamcs Can Be Used Wthn MS-Excel MS-Excel Add-In Thermodynamc functons are added to Mcrosoft Excel and used n spreadsheets as natve functons ProSm Software Sute Smuls Thermodynamcs to perform more or less complex engneerng calculatons (wth rgorous thermodynamcs) to ft BIP of models

56 Smuls Thermodynamcs Can Be Used Wthn MATLAB Smuls Thermodynamcs s provded as a toolbox n MATLAB MS-Excel Add-In MATLAB Toolbox ProSm Software Sute Smuls Thermodynamcs Rgorous thermodynamcs become avalable n MATLAB wthout further programmng effort

57 Smuls Thermodynamcs Can Export Result Fles to Other Packages MS-Excel Add-In MATLAB Toolbox ProSm Software Sute Smuls Thermodynamcs Tabulated results to : MS-Excel Aspen TASC (PSF fle) Export fles OLGA (PVT fle)

58 Smuls Thermodynamcs Can Be Used Wthn Your Software A complete Applcaton Programmng Interface (API) s also provded Vsual Basc C++ Delph FORTRAN C# etc ProSm Software Sute MS-Excel Add-In Smuls MATLAB Toolbox Thermodynamcs Smuls Thermodynamcs can be easly embedded n any applcaton supportng the COM/DCOM technology Export fles A.P.I. However, the nterface between the embeddng applcaton and Smuls Thermodynamcs must be coded Your software (C++, VB, FORTRAN, )

59 Smuls Thermodynamcs Can Be Used Wthn CO Complant Packages ProSm Software Sute MS-Excel Add-In Export fles Smuls MATLAB Toolbox Thermodynamcs A.P.I. CAPE- OPEN "plug" Modelng tool mplementng CO Thermo Socket Aspen Plus, ProII, Aspen HYSYS, HTRI, gproms