Post-Combustion Processes Employing Polymeric Membranes

Transcription

1 Post-Combustion Processes Employing Polymeric Membranes Torsten Brinkmann a, Thorsten Wolff a, Jan-Roman Pauls b a: Institute of Polymer Research b: Institute of Materials Research / Frankfurt 2 nd International Conference on Energy Process Engineering Efficient Carbon Capture for Coal Power Plants June 20-22, 2011 in Frankfurt/Main, Germany

2 Contents Introduction Permeation data and membrane production Membrane module model Pilot plant experiments Process simulation Upscaling aspects Conclusions 2

3 Membrane Process Development Lab. scale investigations Polymer synthesis Polymer modification Permeation behaviour Pilot scale membrane production Pilot plants Module design Process simulation/design Comp. pilot plant/simulation n-c 4 H 10 Mole fraction y R,C4 [-] V m F V m F V m F (STP) (STP) (STP) h h h Lines: Simulation Symbols: Experiment Membrane area A z [m 2 ] 3

4 Contents Introduction Permeation data and membrane production Membrane module model Pilot plant experiments Process simulation Upscaling aspects Conclusions 4

5 Membrane Data - Laboratory Scale Multilayer composite membranes Single gas permeation data HZG data determined using pressure increase apparatus Temperature dependency can be described by Arrhenius type relationship Membrane POLYACTIVE POLYACTIVE 1, PEBAX Cellulose Acetate POLARIS 1 Ref. 1,2 4 L [Nm 3 /(m 2 h bar] CO H 2 O CO2/N [ C] (?) C 1/T [K -1 ] 1. A. Car er al., Adv. Funct. Mater. 18 (2008) C 2. S. Kipp, Diploma Thesis, TUHH/HZG, C. Naderipour, Diploma Thesis, HAW Hamburg/HZG, T. Merkel et al., Selecting Membranes for Carbon Dioxide Capture from Power Plant Flue Gases In Book of Abstracts XXVI EMS Summer School 29 September 2. Oktober 2009 Geesthacht/Ratzeburg, ln(l) POLYACTIVE composite membrane [1] H 2 O CO 2 H 2 CH 4 O 2 N 2 5

6 Membrane Production in m 2 Scale POLYACTIVE multilayer composite membrane O 2 /N 2 permeation data for quality control Coating of selective/ 3.00 protection layers O 2 /N 2 Selectivity O2/N2 [-] Average Casting of porous support Production Batch Length L [m] 6

7 Contents Introduction Permeation data and membrane production Membrane module model Pilot plant experiments Process simulation Upscaling aspects Conclusions 7

8 Retentate Membrane envelope Top view of a membrane envelope Permeate tube Permeate Feed Retentate Permeate Pressure vessel Feed Permeate Feed y R,CH4 R v R Feed Permeate z O-ring Permeate Baffle plate Retentate Simulation Model GS Module Boundary conditions - Module geometry and feed definition Flow patterns: differential balances - Material - Energy - Pressure drop Equation of state - Fugacities - Enthalpies - Densities Permeation - Arrhenius n n z - Free Volume model Concentration polarisation - Mass transfer coefficients - Stefan-Maxwell R,i a n M, i L molar, i f R,i f P,i M,i 0 8

9 Implementation: Aspen Custom Modeler Equation oriented process simulator - Parameterised models - Numerical mathematics - Physical properties - Dynamic simulation - PDE support - Integrated development environment Detailed model development Flowsheet and process development 9

10 Contents Introduction Permeation data and membrane production Membrane module model Pilot plant experiments Process simulation Upscaling aspects Conclusions 10

11 Pilot Plant Operating Conditions Operating data: Membrane area: 7.38 m 2 Feed pressures: 1.4 to 3 bar Feed flowrates: 13 to 34 Nm 3 /h Feed CO 2 mole fraction: 13.7 to 18.0 % Feed temperatures: 20 to 25 C Permeate pressure: 200 mbar Water vapour saturation by employing liquid ring compressor and vacuum pump V1 PDI Feed Compressor Gaschromatograph FI1 PI1 FI2 QI1 External vacuum pump Membrane module QI3 V3 PI2 QI2 V2 Permeate vacuum pump Feed vessel 11

12 Pilot Plant Experimental Results CO 2 Mole Fraction Permeate y P,CO2 [-] pf = 3 bar pf = 2 bar pf = 1.4 bar pf = 3 bar, Sim pf = 2 bar, Sim pf = 1.4 bar, Sim CO 2 Mole Fraction Retentate y R,CO2 [-] pf = 3 bar pf = 2 bar pf = 1.4 bar pf = 3 bar, Sim pf = 2 bar, Sim pf =1.4 bar, Sim Volumetric Flowrate Feed V F [Nm 3 /h] Volumetric Flowrate Feed V F [Nm 3 /h] 0.25 Feed V = 13 to 34 F Nm3 /h y F,CO2 = 13 to 18% p F = 1.4 to 3bar F = 20 to 24 C Gas permeation module y R,CO2 A=7.4m 2 V P y P,CO2 p P = 0.2 bar Retentate Permeate Stagecut V F /V P [-] Volumetric Flowrate Feed V F [Nm 3 /h] pf = 3 bar pf = 2 bar pf = 1.4 bar pf = 3 bar, Sim pf = 2 bar, Sim pf = 1.4 bar, Sim 12

13 Pilot Plant Results Interpretation Operating behaviour of module as expected Module and membranes were used in biogas pilot plant before Simulation model predicts performance satisfactorily Single gas permeation data to predict multicomponent mass transfer Deviations experiment simulation - Influence of water permeation on other components correctly considered? 13

14 Contents Introduction Permeation data and membrane production Membrane module model Pilot plant experiments Process simulation Upscaling aspects Conclusions 14

15 Input Data Power plant [1] Process simulation Coal fired power plant Aspen Custom Modeler Nominal power: 600 MW Membrane module model Efficiency: 45.9% - Cross flow with free permeate withdrawal Flue gas: - Permeances as function of temperature, V = Nm 3 /h pressure and composition based on single p = bar gas experiments = 48 C - Real gas and Joule Thomson effect y CO2 = considered y H2O = No pressure drops and mass transfer y N2 = resistances Rotating equipment - Isentropic efficiency of 85 % - Assumed as adiabatic compressors or turbines - No specific type assumed 1. Notz et al., Chem. Ing. Tech. 82 No.10 (2010)

16 Performance of POLYACTIVE Composite Membranes: Humid Flue Gas Specific Energy for Capture [kwh/t CO2 ] Feed V F = Nm 3 /h y F,CO2 = p F = bar y F,H2O = F = 48 C y F,N2 = S1 B5 S13 Cooling Compression GLSep_1 S10 Water_1 Blower S5 Cooler_1 p = 1.1 bar = 30 C CO 2 Recovery [-] S15 GLSep_2 S4 S Permeation data (average values at 30 C): L CO2 L H2O CO2/N2 = 36 MembraneStage_1 Retentate_OffGas Cooler_3 Permeate_1 p = 0.1 bar Expander Recycle p = 4 bar = 30 C Water_2 S6 VacuumPump_1 S7 Compressor S8 MembraneStage_2 S3 GLSep_4 GLSep_3 Cooler_2 S12 S9 Membrane Area [m 2 ] = 4.3 Nm 3 /(m 2 h bar) = 43.4 Nm 3 /(m 2 h bar) Water_3 Water_4 CO2 y P,CO2 = 0.95 Flowsheet: Zhao et al., J. Membr. Sci. 359 (2010)

17 Performance of POLYACTIVE Composite Membranes: Operating Temperatures Specific Energy for Capture [kwh/t CO2 ] Feed S1 B5 Compression 30 C 20 C GLSep_1 S10 Water_1 V F = Nm 3 /h y F,CO2 = p F = bar y F,H2O = F = 48 C y F,N2 = E C E CO 2 Recovery [-] Blower Cooler_1 S13 S5 Membrane area S2 p = 1.1 bar Recycle GLSep_2 S4 Water_2 VacuumPump_1 1.40E E E E E E+06 MembraneStage_1 Membrane Area [m 2 ] Permeate_1 S8 S9 GLSep_3 Retentate_OffGas p = 0.2 bar MembraneStage_2 Cooler_2 [ C] S3 Water_3 VacuumPump_2 Cooler_3 L [Nm 3 /(m 2 h bar] CO H 2 O p = 0.2 bar S7 y P,CO2 = 0.95 GLSep_ CO2 CO2/N2 Water_4 17

18 Contents Introduction Permeation data and membrane production Membrane module model Pilot plant experiments Process simulation Upscaling aspects Conclusions 18

19 Possible Module Design Envelope type modules allow for easy scale-up Possible to minimise permeate side pressure drops: important for vacuum assisted operation Membrane sheets are thermally welded: no additional components as e.g. adhesives Proven technology for the manufacture of flat sheet membranes on industrial scale 19

20 Vacuum Pumps Steam ejector vacuum pumps [1] Max. capacity: m 3 /h (about half of the flowrate required for 1st stage) One stage vacuum: 100 mbar High motive steam demand 1 motive medium connection 2 motive nozzle 3 head 4 diffuser inlet 5 diffuser outlet A pressurised motive medium p Retentate > p d > p Permeate B suction flow (permeate) at pressure p Permeate C mixed flow at pressure p d Liquid rings vacuum pumps [2] Sterling SIHI: m 3 /h at 100 mbar ZM Engineering: m 3 /h at 180 mbar New vacuum pump concepts required 1. Körting Hannover AG, Arbeitsblätter für die Strahlpumpen-Anwendung, 2. Sterling SIHI GmbH, 20

21 Conclusions POLYACTIVE composite membrane - Permeance and selectivity are suitable - Can be produced on large scale Accurate module models are required to develop efficient process designs Piloting is essential - Process performance - Influence of various components - Determination of unknowns (level of filtration necessary, ) Competitive process designs have been developed (Merkel et al., Zhao et al.) - Important to consider water - Cooling has to be accounted for - Integration with power plant process New vacuum pump concepts required Novel module concepts would be advantageous 21