Dortmund Data Bank (DDB) DDB Software Package (DDBSP)

(1)

1

Dortmund Data Bank (DDB)

DDB Software Package (DDBSP)

Practical Application of Distillation Synthesis

for NOx Reduction, Energy Cost Savings, & Improved Environmental Compliance

Dr. Juergen Rarey, Managing Director, DDBST, Oldenburg Germany, www.ddbst.com Todd J. Willman PE, ChemE, MBA, EPCON International, Houston, TX, www.epcon.com

Showcase on Technology

(2)

2

Aspects to be Considered During the Synthesis of Separation

Processes 1 01 01 012 Bedeutung 10.02.03

Separation

Process

?

N

_th

=?

?

x₁ x₁ y₁ T ₁₂= ₁ _P₁s ₂ _P₂s 1

Suitable Solvent for Extractive or Azeotropic Distillation ?

?

ABCD AB CD A B C D S =_n [2(n-1)]! n! (n-1)! T n-1 Distillation ? Crystallization ? Separation Problems ? Sequence ? Column Height ? sepproc5_e.cdr Water (3) Ethanol (1) Benzene (2)

(3)

3 Advantages of Distillation Compared to Other Separation Processes 10 00 002 Synthese 28.02.03

scheme of a separation process

Streams of different composition Stage i

Feed

energy/entrainer to generate different streams

Advantages of distillation processes compared to

other separation processes Disadvantages of distillation

a) Energy as "entrainer"

b) Simple phase separation due to large

difference in density between liquid and vapor phase

c) Simple transport of fluid phases helps to realize large number of stages

d) Long time experience

(estimated throughput in 1992: 5.2*109_t/a) Due to these advantages distillation is also used for the separation of azeotropic

mixtures

High energy consumption

In 1989 approx. 3% of the total US energy consumption was required to operate 40 000 distillation columns

(4)

4 Residual Curves 04 00 021_e AZD 11.02.03 intermediate boiling component low boiling component high boiling component x₀ _x (t) Vapor Liquid

x

_(t)

x

₀

=

x

_(t=0) x_(t) Simple Distillation Boundary

P = 1 atm

Benzene Cyclohexane Acetone T = 80.1 °C_b T = 56.1 °C_b T = 80.7 °C_b 77.5 °C 54.2 °C x_(t) x₀ x₀

(5)

5

Residual and Boundary

Residual Curves

04 00 022 AZD 11.02.03 Benzene Cyclohexane NMP 202.0 °C 80.1 °C 80.7 °C 77.5 °C Benzene Cyclohexane Acetone 80.1 °C 80.7 °C 56.1 °C 77.5 °C 54.2 °C Benzene Cyclohexane 2-Butanone 80.1 °C 80.7 °C 79.6 °C 77.5 °C 78.4 °C 71.2 °C

A)

B)

C)

(6)

6

Heteroazeotropic

Distillation

10 00 005 Synthese 11.02.03

Water (3)

100.00°C

69.60°C

78.14°C

64.76°C

67.96°C

Ethanol (1)

78.30°C

Benzene (2)

80.10°C

A

B

C

Ethanol

Water

Benzene

A

Ethanol

Water

HeteroazeotropicDistillation.cdr

B

D

C

E

(7)

7

mod. UNIFAC (Do.), 1 atm

(1) 56.4 °C (2) 61.1 °C (3) 64.9 °C (4) 78.3 °C (1)-(2) 64.3 °C (1)-(3) 55.4 °C (2)-(3) 53.7 °C (2)-(4) 59.9 °C (1)-(2)-(3) 57.6 °C (1)-(2)-(4) 63.2 °C

stable node

unstable saddle

unstable node

ResidueCurves+BorderPlane s.ppt 11.02.03 Residue Curves and Border Planes

in the System Acetone(1) – Chloroform(2) –Methanol(3)

(8)

8

Product Regions in the System Water (1) + Ethanol (2) + Benzene (3) for Different

Feed Compositions

04 00 025c AZD

11.02.03

P = 1 atm

Modified UNIFAC (Dortmund)

ideal vapor phase

(1)-(2)-(3) 64.89 °C

(1)-(2) 78.14 °C

(1)-(3) 69.23 °C

(2)-(3) 67.66 °C

Ethanol (2)

78.30 °C

Benzene (3)

80.10 °C

Water (1)

100.00 °C

D

B

F

D

B

F

(9)

9

Azeotropic und Extractive

Distillation

10 00 007 Synthese

(10)

10

(11)

11

Scope of DDB

1 - Basic Data 2 - Experimental Data (from Literature)

3 –Molecular Structures (ChemDB)

4 –Model Parameters (ParamDB)

5 –Literature Sources and Documents (LEAR)

6 –COSMO -Profiles

(12)

12

Status of the Dortmund Data Bank* (Sept. 2006)

52000 References, 1800 Journals, 20300 Compounds plus Salts, Adsorbents and

Polymers 26.01.06

DDB

26500 (VLE) 5920 (ELE) 25100 (HPV)

VLE**

(total: 57520 data sets)

* detailed information is available via internet (www.ddbst.de)

** including unpublished VLE data of companies from the former German Democratic Republic

17400 data sets for non-electrolytes 16420 data sets

LLE

49000 data points

azeotr. data

3500 data sets

ADS

27700 data sets

v

E 2150 data sets

c

PE 17900 data sets

h

E

18300 data sets for non-electrolytes

15800 data sets for electrolytes

(E)SLE

47700 data points for pure solvents

c

_P



P



iS

153200 data sets

(E)GLE

1100 data sets for electrolytes 1120 data sets

for solvent mixtures

1320 data sets

CRI

Pure Component Properties

7250 data points

KOW

Polymers new 15420 data sets

(13)

13

D

ortmund

D

ata

B

ank

S

oftware

P

ackage

(DDBSP)

11.02.03

Calculation Programs Parameter Fitting

PCP Presentation Programs

DDB - Mixture Data

VLE hE ACT GLE LLE AZD SLE ...

DDB - Pure Component Data

P_is c_P crit.  T_m h_fus Recommended Values Recommended Values Prediction Prediction Wilson NRTL UNIQUAC SRK PR ... UNIFAC Mod. UNIFAC (Do) ASOG PSRK ...

... Phase Equilibria Simulation Programs Flash Points Process Synthesis UNIFAC

Mod. UNIFAC (Do) PSRK LIQUAC experimental correlated predicted Diagrams Tables DDBSP_jumpstart.cdr; 22.08.2001

(14)

14

Experimental and Predicted Azeotropic Data for the

Quaternary System at P = 101.325 kPa Benzene (1) Cyclohexane (2) -Acetone (3) - Ethanol (4) 04 00 024a AZD 11.02.03

* mean values of the experimental data stored in the Dortmund Data Bank n.a.: not

available

predicted (mod. UNIFAC (Do)) experimental* system type of

azeotrope

/ °C y1,az y2,az type of

azeotrope / °C y1,az y2,az 1-2 homPmax 77.5 0.543 homPmax 77.6 0.543 1-3 none none 1-4 homPmax 68.0 0.537 homPmax 67.9 0.552 2-3 homPmax 54.3 0.221 homPmax 53.2 0.248 2-4 homPmax 65.3 0.545 homPmax 64.8 0.553 3-4 none none 1-2-3 none none 1-2-4 homPmax 65.1 0.126 0.441 homPmax 64.9 0.113 0.462 1-3-4 none none 2-3-4 none none 1-2-3-4 none n.a.

(15)

15

Residual Curves in the System Ethanol (1) Benzene (2) -Water (3) at P=1atm 11.02.03 04 00 024 AZD

Water (3)

100.00°C

69.60°C

78.14°C

64.76°C

67.96°C

Ethanol (1)

78.30°C

Benzene (2)

80.10°C

A

HeteroazeotropicDistillation.cdr

B

D

C

E

(16)

16

Entrainer Selection

and Contour Lines

separation factor of 1 up to 22 mol% of NMP



_

< 0.65



_

< 0.4

properties along this line or parallel typically

shown on solvent free basis

(17)

17

Selection of Selective Solvents with the Help of Thermodynamic

Models or DDB 11.02.03 Input: Components Pressure (Temperature) Distillation Process Examination of the binary VLE behavior

Search of binary data (azeotropic data, ) for component 1 and 2

 Search of ternarydata with component 1 and 2

Output:

List of suitable solvents including experimental information Selection criterion fulfilled ? Determination of and T (P ) for given P(T) ₁₂ _az _az DDB-MIX azeotropic data (45100 values) (36700 values)  Recommendation of alternative distillation processes in case of: 1. Zeotropy 2. Heteroazeotropy 3. Strong pressure dependence of y 4. Zeotropy at low (high) pressure az Input: Output:

List with selective solvents a) extractive distillation b) azeotropic distillation 1) ... 2) ... 3) ... Are solvents suitable ? Recommendation of alternative distillation processes the case of: 1) Zeotropy 2) Heteroazeotropy 3) Strong pressure dependence of yaz 4) Zeotropy at low (high) pressure Examination of the

binary VLE behavior Preselection of potential solvents with the help of predicted i values  Prediction of ternary azeotropic data (1 + 2 + solvent) Selective_Solvent_Models_DDB.cdr 22.08.2001

(18)

18

Selection of Selective Solvents for Extractive Distillation

10 00 021 Synthese

11.02.03

Components to be separated: P = 101.32 kPa

(1) Cyclohexane C6H12 Tb(2) = 353.86 K azeotropic data for system (1)- (2):

(2) Benzene C6H6 Tb(1) = 353.25 K type of azeotrope : homogeneous pressure maximum, Tb = 351.47 K

DDB - access

selective solvent (3) (1,2), inf. (T [K]) [EMIM] ethylsulfate

N-Butylpyridinium BF4

-20.77 (303.15K) 20.00 (298.00K) [EdMIM] bis(CF3SO2)imide 15.38 (298.00K)

[EMIM] bis(CF3SO2)imide 13.51 (298.00K)

4-Methyl-N-butylpyridinium BF4- 12.82 (353.56K) Tetrahydrofurfuryl alcohol 4.05 (300.15K) N-Formyl-morpholine 3.80 (408.73K) Nitrobenzene 3.48 (397.02K) N-Methyl-2-pyrrolidone 3.45 (394.07K) Cyclohexanone 3.41 (293.15K) Furfural 3.29 (380.59K) Aniline 3.13 (387.94K) Anisole 3.05 (293.15K)

modified UNIFAC (Dortmund)

selective solvent (3) (1,2), inf. (T [K]) Adipodinitrile 8.70 (353.56K) 2,5-Hexanedione 4.95 (353.56K) N-Methyl-2-pyrrolidone 4.93 (353.56K) Furfural 4.11 (353.56K) Aniline 4.02 (353.56K) Acetophenone 3.83 (353.56K) Triethylene glycol 3.03 (353.56K) Nitrobenzene 2.88 (353.56K) Cyclohexylamine 2.80 (353.56K) 3-Methylphenol 2.10 (353.56K) Tetrahydrofurfuryl alcohol 2.07 (353.56K) Cyclohexanone 2.06 (353.56K) Anisole 1.72 (353.56K)

(19)

19

Typical Result for the Search of Suitable Solvents by DDB

Access

10 00 023 Synthese

(20)

20

Typical Result for the Search of Selective Solvents

with the Help of a Thermodynamic Model

10 00 024 Synthese

(21)

21

Software Demonstration

(22)

22

Conclusion

Azeotropic conditions can be overcome (and energy reduced) by selecting a

suitable solvent for azeotropic or extractive distillation, extraction –this can be best

accomplished using a large, highly accurate experimental data bank or powerful predictive models.

The action of an entrainer for extractive distillation results from the different activity coefficients of the components to be separated in the entrainer. The greatest effect is usually observed when the components are infinitely diluted in the entrainer. The effect of the entrainer on the activity coefficients can result in an azeotropic point of one of the components with the entrainer.

Solvent Selection either uses the DDB or the results of predictive models (UNIFAC,

…) as a source for activity coefficients (ACT) or azeotropic data (AZD). The program

is very powerful and has many important options, only very simple example were shown here.

Running distillation separation processes under azeotropic conditions means that purity cannot be improved no matter what additional energy is added to the process. A column analyzed and optimized with Distillation Synthesis can have significantly

reduced overall energy demands –directly, positively impacting NOX reduction and