Energy Analysis of CO Separation Process with Hollow Fiber · PDF filewith Hollow Fiber...

Fifth Annual Conference on Carbon Capture & Sequestration

Capture – Membranes (2)

Energy Analysis of CO2 Separation Process with Hollow Fiber Membrane

Using ASPEN Simulation Method

Hyung-Taek Kim and Hyun-Min ShimDept. of Energy Studies

Ajou University, Suwon Korea

Contents

Background

Purpose of the Study

Simulation & Analysis Method

Schematic of Process

Results of Simulation

Conclusion

Future Work

Background• Carbon Dioxide (CO2)- Major source of greenhouse gas from Power Plant & Industrial Process- CO2 Emission : Korea ranked 10th in the world- Kyoto Protocol : Expected to add carbon tax, emission trade

• For sustainable development, Korea must prepare for the duty for reduction of CO2 emission.

• Methods of CO2 separation : Absorption, Adsorption, Membrane- Absorption : Low conc. CO2 recovery process & large scale

Commercial plant / Blazing of absorbent, Leakage

- Adsorption : High conc. CO2 recovery process & middle scaleShort lifetime of adsorbent

- Membrane : More environmental-friendly than absorptionHigh conc. CO2 recovery process & small scaleNeed to construct commercial plant in Korea

Purpose of the study

• Perform simulation of CO2 separation process with hollow fibermembrane by ASPEN plus & Excel.

• It is possible to analyze the actual process including unit equipments, and obtain optimum operation parameters of product or intermediate.ex) pressure, temperature, enthalpy, flow, composition etc

• Evaluating energy analysis of CO2 separation process and calculating cost of operation are required for CO2 separation & recovery.

Scale : 1,000 Nm3/day of LNG Flue GasTarget Recovery rate : 90%

Purity of CO2 : 99%

Schematic of Hollow Fiber Membrane

H2O > CO2> O2>N2 N2

CO2N2

flue Gasflue Gas

2.01.7O2

100100Total11.018.2H2O13.98.8CO2

72.271.3N2

Wt %Vol %Composition

0.167Pressure ratio (P2/P1)60 GPUPermeability [CO2]50 cmLength of HF20Selectivity [CO2/N2]

1000 m3/dayFeed rate0.1P2 (atm)16,000Num of HF6P1 (atm)

AmountParameterAmountParameter

2) Parameters of Hollow Fiber Membrane

1) Composition of LNG Flue Gas

Simulation & Analysis Method (1/2)• Operating Conditions

Simulation & Analysis Method (2/2)

• Final Results

- Volume of Permeate (VP)- Volume of Retentate (VR)- CO2 Purity at Permeate - CO2 Recovery (%)- Required Surface Area of Membrane (A)

- Required amount of MembraneModule (n)

Initial Input Parameters for Membrane Module

- Permeability (Barrer) - Selectivity(CO2/N2) - Thickness of Selective layer (mm)

• Initial Input Parameters for Variables of Process

- Pressure Ratio( R ) : P feed / P perm- Stage-cut : Q feed / Q perm- Operating Temperature- Plasticizing

• Operating Conditions → Simulation for CO2 Separation Process (Supplement ofMembrane Model with Excel in ASPEN code) → Simulating Results → FindingOptimal Conditions → Energy Analysis by Exergy Method → Calculating Capital Cost

Schematic of Process• Evaluated CO2 Separation Plant (Capacity: real exhaust gas, 1000 Nm3/day)at the Korea Research Institute of Chemical Technology (KRICT)

1. H2O removal process

2. CO2 separation process

3. CO2 liquefaction process (Not yet)

Simulation of H2O Removal Process

FLUEGAS

COOLIN1

HTFLUG1

COOLOUT1

PHTFLUE

COOLIN2

COOLFLUE

COOLOUT2 DRYFLUE

DRN-H2O

PRECOOL

COMP

CONDENSCO2SEP

• Simulation of H2O Removal Process by ASPEN code

Gas Pre-CoolerT: 150 / 40P: 1 kg/cm2

CompressorTmax : 150OP : 6 kg/cm2

CondenserT: 150 / 25P: 6 kg/cm2

H2O SeparatorTmax : 25OP : 5.6 kg/cm2

•

••••

•

Simulation of H2O Removal Process

•

Simulation of H2O Removal Process

Simulation of 1 Membrane Module

•

2 1 ( 1)( 1) 1 0i ix xy y

R R Rα αα α −⎛ ⎞− + − − − + =⎜ ⎟

⎝ ⎠

1 2

( ) ( )( ) ( )

( ) ( )

out out

A out A i ave

out

i ave

Vy VyAJ Q Px P y

VyPermeate flux x Ry

= =−

=× −

1

2

2 1

: selectivity : Feed composition : Permeate composition: Feed Pressure: Permeate Pressure : Pressure ratio( ) : Permeate rate : membrane area

i

xyPPR P PVA

α

flux and conc. of

2. Simulation with variation of membrane property1) Fix permeability as 20, then change selectivity 20~1002) Fix selectivity as 20, then change permeability 20~1003) Change permeability as well as selectivity 20~100

Simulation of 1 Membrane Module

•

� � � � � � � � � � � � � , � � � �

3636.5

3737.5

3838.5

3939.5

40

5 6 7 8 9 10 11 12 13 14 15

� � (atm)

� � (%)

9.49.59.69.79.89.91010.110.210.310.4� � (m3/hr)

ya V

� � � � � � � � � � , � � � � � �

0

50

100

150

200

250

300

350

5 6 7 8 9 10 11 12 13 14 15

� � (atm)

� � � (m2)

0102030405060708090100� � � �

Area Module

Simulation of 1 Membrane Module

� � � � � � � � � � � � � � �

02468

101214

10 20 30 40 50 60 70 80 90 100

� � � � �

� � (m3/hr)

V

� � � � � � � � � ,� � � � � �

0

1020

30

40

5060

70

10 20 30 40 50 60 70 80 90 100

� � � � �

� � (%)

0.00E+001.00E+002.00E+003.00E+004.00E+005.00E+006.00E+007.00E+008.00E+009.00E+00� � (%)

ya XT

Simulation of 1 Membrane Module

1. Permeability = 20, selectivity = 20~100

� � � � � � � � � � � � � � � � � �

02468

1012

20 30 40 50 60 70 80 90 100

� � �

� � �(m3/hr)

00.10.20.30.40.50.60.7� � � �

permeate rate CO2 conc of permeate

� � � � � � � � � � � � � � � � � �

240

245

250

255

260

20 30 40 50 60 70 80 90 100

� � ����

(m2)

75

77

79

81

83

�����

membrane area No of modules

Simulation of 1 Membrane Module

� � � � � � � � � � � � � � � � � � �

050

100150200250300

20 30 40 50 60 70 80 90 100

� � �

� � � (m2)

0

20

40

60

80

100� � � � �

membrane area No of modules

2. Selectivity =20, permeability = 20~100

Simulation of 1 Membrane Module

� � � ,� � � � � � � � � � � � � � � � � �

02468

1012

20 30 40 50 60 70 80 90 100

� � � � � � �

� � � (m3/hr)

00.10.20.30.40.50.60.7� � � �

permeate rate CO2 conc of permeate

� � � ,� � � � � � � � � � � � � � � � � � �

050

100150200250300

20 30 40 50 60 70 80 90 100

� � � � � � �

� � � (m2)

0

20

40

60

80

100� � � � �

membrane area No of modules

3. Permeability & selectivity = 20~100

Simulation of 1 Membrane Module

Simulation of 4 membrane

DRYFLUE PERM1

RET1

4

PRET-11

DRNW-1

PRET-12

PRET-13

DRNW-2

CWIN-1

PRET-14

CWOUT-1

PERM2

RET2

PRET-21

DRNW-3

PRET-22

PRET-23

DRNW-4

CWIN-2

PRET-24

CWOUT-2

PERM3

RET3

PRET-31

DRNW-5

PRET-32

PRET-33

DRNW-6

CWIN-3

CWOUT-3

PRET-34

RET4

PERM4

MEMB-1

PUMP-1

BTK-1 COMP-1

BTK-2

AFCOOL-1

MEMB-2

BTK-3

COMP-2

BTK-4

AFCOOL-2

MEMB-3

BTK-5 COMP-3

BTK-6

AFCOOL-3

MEMB-4

User Model (Excel) for Membrane Modules in ASPEN code

• Simulation of CO2 Separation Process by ASPEN (Excel) code (Peng-Rob equation)

Linkage

→ 4 cascade of hollow fiber membraneCO2 Separation Process

Simulation of 4 membrane

-98.7498.6171.9554.45Recovery (%)

110.06( 1 )0.27 ( 1)1.17( 2)6.03( 7)Required Module (EA)

-41.641.8105.5145.91Flow rate (m3/day)

Total4321Stage

• 4 cascade membrane modules without recycling retentate

feedfeed

permeatepermeate

COQCOQ

CO][][

)(2

22 ×

×=ψ

• Recovery, ψ (%)

Qfeed

[CO2]feed

Qretemtate

Qpermeate

[CO2]permeate

Pfeed

Ppermeate

Simulation of 4 membrane• 4 cascade membrane modules without recycling retentate

875154.4516/0.1

Pfeed / Pperm328071.9526/1

119498.6136/1

1(0.5)199.098.7446/1

119798.3446/1218994.4036/1347067.8426/1

20403225.6716/1

Pfeed / Pperm

EXPSIMEXPSIM

Required amount of Module (7m2)Recovery (%)

StageValue (kgf/cm2)Parameter

Comparison of result for Experiment/SimulationOperating Conditions

Simulation of CO2 Liquefaction Process

LPERCO2

LCOMP

PLPERCO2

LCONDS

CBS

CPLPRCO2

CBR

LQCO2TK

VCO2

LCO2

VCO2MIX

MXCO2

• Simulation of CO2 Liquefaction Process by ASPEN code (Peng-Rob equation)

ChillerT: 25 / -57P: 51.8 kg/cm2

CompressorT: 25P: 52 kg/cm2

CO2 V-L Separator

Conclusions

1. Simulation method for CO2 membrane separation is developed- Simulation program composed with H2O removal, membrane modules and CO2 liquefaction processes

2. Evaluation of optimal condition of 1 membrane - Obtaining optimum parameters with fixing the concentration of

retreate and pressure as well as the variation of permeability and selectivity

3. Development of membrane model using ASPEN & EXCEL - Performing the simulation between ASPEN and EXCEL (User model)

Future Work

1. Refine of membrane model using ASPEN & EXCEL - Link between ASPEN and EXCEL (User model)

2. Evaluation of optimum operation parameter - Obtaining the optimum parameters with change of pressure,

selectivity, permeability etc. with 4 membrane module

3. Simulation for detail equipments- Energy requirement calculations for Vacuum pump, Compressor,

Condenser for CO2 liquefaction process

4. Energy requirement & cost calculations through exergy analysis - Using each stream results by simulation for exergy calculation

Thank you