paul j. grimmer , xiaobing xie, carl r. evenson iv ... transport across eltron’s membrane h-h h-h...

Eltron Research & Development

High-Pressure Operation ofDense Hydrogen Transport Membranes

for Pure Hydrogen Productionand Simultaneous CO2 Capture

Twenty-Third Annual InternationalPittsburgh Coal Conference

September 26, 2006

Paul J. Grimmer, Xiaobing Xie, Carl R. Evenson IV, Michael V. Mundschau, Harold A. Wright

Eltron Research


Slide 2

Outline

� Introduction

� Project Goals

� Membrane Scale-Up Designs

�Planar

� Tubular

� High-Pressure Results

� Future Work


Slide 3

Project Goals

� Fabricate hydrogen separation membrane system which can retain CO2 at coal gasifier pressures (450-1000 psi) for minimizing compression costs for CO2 sequestration

� Fabricate membrane system for tolerance to water-gas shift reactor conditions (450-1000 psi; 360-400oC; 41% H2 max; coal-derived impurities)

� Deliver pure hydrogen for use in fuel cells; hydrogen turbines; hydrocarbon fuel processing


Slide 4

Role of Hydrogen Separation Membranesin CO2 Sequestration

2352mvm.dsf

ParticulateRemovalSystem

CatalystGuardBeds

Water-Gas Shift

Reactor

40% H2 +CO2 + H2O

340-440°C1000 psi

H2 + CO

320-440°C1000 psi

Synthetic FuelsPetroleum RefiningFuel Cells

Electricity

H2O

Compress H2

435 psi

Steam320°C

1000 psi

H2 + CO

320°C1000 psi

Electricity

H2O

H2O

H2 + COSynthesis Gas

H2 + CO

1040°C1000 psi

SteamTurbine

1000 psiCO2

H2O

Slag Oil + GasRecovery

HeatExchanger

320°C1000 psi

320°C1000 psi

Steam

Oxygen

H2

CoalGasifier

>1040°C1000 psi

HydrogenTurbine

CoalSlurry

Oxygen

HydrogenSeparation

Unit

AirAirSeparation

Unit

N2

<400 psi

CO2 Sequestration Condense H2OCompress CO2 2700 psiCO2 Pipelines


Slide 5

Eltron Hydrogen Transport Membranes

MembraneType

Operating TemperatureRange (oC)

Permeation Rate(mL•min-1•cm-2)

Single PhaseCeramic

700 to 950 ~ 0.01

Ceramic / Ceramic 700 to 950 ~ 0.1

Cermet 700 to 950 ~ 1

Cermet with H2

Permeable Metal550 to 950 ~ 4

Intermediate TemperatureLayered Composite

320 to 440 20 - 420


Slide 6

Hydrogen Transport Across Eltron’s Membrane

H-HH-H

H-H

H-H

Layers ofHydrogen

DissociationCatalyst

HydrogenTransport

MembraneMaterial

H-HH H H H

H HH H

H

HydrogenDissociation

Diffusion of Hydrogen inDissociatedForm

Recombination and

Desorption of H2

HH

H-H

H-H


Slide 7

� Precedence for a 10 million cubic feet (25 tons) per day hydrogen plant using membranes (Pd-Ag) (Union Carbide, 1960s, Patent 3,336,730, Aug. 22, 1967)

Previous Scale-Up Design – Planar (Union Carbide)


Slide 8

Precedence for a 10 MMCFD (25 ton) Hydrogen Plant Using Membranes

(Union Carbide, 1960s)

� Operated 10 MMCFD plant in 1960sin South Charleston, West Virginia

� Proved that large-scale hydrogen-membrane purification units arefeasible

� Used dual guard beds to removeimpurities

� Feed 500 psi (34.5 bar)

� Used Pd-Ag membranes (price ofPd now prohibitive, ~$200,000,000?)

Previous Scale-Up Design – Planar (Union Carbide)


Slide 9

Previous Scale-Up Design – Planar (SOFCo)

SOFCo Planar Design(DE-FC26-OINT41145)

�Wafer panel length 2 m (6.55 ft)

�159 stacks

�590 tons per day of hydrogen (234 MMSCFD)

�FutureGen: Need to evaluate merits of tubular versus planar


Slide 10

Concepts For Membrane Scale-Up:Metal Tube Heat Exchangers

NORAM tubular membrane design based on tantalum-tube heat exchangers.


Slide 11

A. Concept for closed-one-ended ceramic tubes bundled for cermet membrane applications. B. Bundle of ceramic membrane tubes produced by CoorsTek for an earlier industrial separation application.

A

1897mvm.dsf

B

Scale-Up of Cermet Membranes


Slide 12

Scale-Up Designs – Tubular (NORAM)

� NORAM conceptual tubular design of a commercial membrane unit capable of separating 25 tons per day (~10 MMSCFD) of hydrogen. Sizing is based upon syngas at 1000 psig (68 barg), 450oC, 50 vol.% H2 in feed.

Water-gas shift mixture entrance

Concentrated CO 2 exhaust

Closed end o f tubes

M embrane tubes

Hydrogenexit


Slide 13

High Pressure Reactor −−−− Eltron Research

�Pressures up to 1000 psi

�Tests in Water-Gas Shift Mixture

�Eltron has only facility in U.S. capable of testing hydrogen transport membranes under extreme pressure conditions.


Slide 14

• Sieverts’ Law followed very well.

• 100% Selectivity to H2. No He leak.

• Permeability 440oC:2.3x10-7 mol m-1 s-1 Pa-0.5.

• Flux:423 mL min-1 cm-2 (STP).

• Disk withstood 33 bar differential pressure –minimum distortion.

Results: Hydrogen Flux Measurements at High Pressure and High Pressure Differential

Membrane: Group IVB-VB Material

Hydrogen Partial Pressure at Feed Side (bar)

0

100

200

300

400

500

0 500 1000 1500 2000

pf1/2

-ps1/2

(Pa1/2

)

H2

Flu

x (

mL

·min

-1·c

m-2

ST

P)

342314841

Ideal H2/He in feed

130 microns thick

16 mm diameter disk

440oC


Slide 15

0

10

20

30

40

50

0 24 48 72 96 120 144 168 192 216 240

Time (hours)

Hyd

rog

en

Flu

x (

mL

min

-1 c

m-2

ST

P)

High-Pressure Hydrogen Flux Data (380oC)

• Membrane ~500 microns thick.

• Feed Pressure: 66.5 bar (964 psi) absolute; 41% H2

• Permeate Pressure: 7.4 bar (107 psi) absolute; pure H2


Slide 16

0.00E+00

5.00E-08

1.00E-07

1.50E-07

2.00E-07

2.50E-07

3.00E-07

0 24 48 72 96 120 144 168 192 216 240 264 288

Time (hours)

Pe

rme

ab

ilit

y

(mo

l m

m-2

s-1

Pa

-1/2)

High-Pressure Permeability Data (380oC)

• Permeability about ten times better than palladium

• Feed Pressure: 66.5 bar (964 psi) absolute; 41% H2

• Permeate Pressure: 7.4 bar (107 psi) absolute; pure H2



Slide 17

0

10

20

30

40

50

60

70

80

0 200 400 600 800 1000

P f1/2

- P s1/2

(Pa1/2

)

Hy

dro

gen

Flu

x (

mL

min

-1 c

m-2

ST

P)

Increasing feedpressure, permeatepressure=4psig

Increasing permeatepressure, feedpressure=480psig

Increasing feedpressure, permeatepressure=90psig

High-Pressure Hydrogen Flux Data (380oC)


• Hydrogen flux >70 mL min-1 cm-2 (STP) as feed pressure approaches 1000 psi (69 bar) with 41% H2 M feed and low permeate pressure.

• Hydrogen flux drop with high hydrogen partial pressure in permeate in accord with Sieverts' Law.


Slide 18

0

10

20

30

40

50

60

70

0 200 400 600 800 1000

P f1/2- P s

1/2 (Pa1/2)

H2 F

lux

(m

L·m

in-1

·cm

-2 S

TP

)

Sieverts' Law

High-Pressure Hydrogen Flux Data −−−−Water-Gas Shift Mixture (440oC)

• Hydrogen flux >50 mL min-1 cm-2 (STP) with 450 psi water-gas shift mixture: 41.0% H2, 17.5% CO2, 3.0% CO, 38.0% H2O, balance He

• Pure hydrogen in permeate, 2.9 bar (42 psi) absolute



Slide 19

High CO conversion of 96% and hydrogen productivity of 75% were achieved when an integrated membrane/shift reactor was operated at 120 psig on the feed side and ambient pressure on the permeate side without a sweep stream. The feed stream used 2000 h----1 GHSV, and contained 47.8 mol% H2, 6.2 mol% CO2, 7.8 mol% CO, and 38.2 mol% steam.

0

10

20

30

40

50

60

70

80

90

100

0 20 40 60 80 100 120 140

Differential Pressure (psi)

CO

Co

nv

ers

ion

(%

)

0

10

20

30

40

50

60

70

80

90

100

Hy

dro

ge

n P

rod

uc

tiv

ity

(%

)

CO conversion

H2 productivity

GHSV = 2000/h, Temperature: 380oC

F81-33CD

Feed (mol%)

H2 47.8%

CO2 6.2%

CO 7.8%

H2O 38.2%

Increased CO Conversions and Hydrogen Productivity with Integrated Membrane

Water-Gas Shift Reactor


Slide 20

High-Pressure Test Results −−−− Summary

� Hydrogen flux >50 mL min-1 cm-2 (STP) under water-gas shift mixture at 450 psi at 440oC with 44 psi pure hydrogen in permeate (fuel cell use).

� Stable under tests up to 970 psi in feed and 500 psi pure hydrogen in permeate (under ideal hydrogen-helium).

� Permeate hydrogen pressure can equal partial pressure of hydrogen in feed.


Slide 21

Future Work

� Test under water-gas shift mixture to 1000 psi (69 bar)

� Identify economic routes to membrane scale-up

� Scale-up membrane modules

� Address issues of coal-derived impurities

� Improve membrane catalysts

� Incorporate warm-gas cleanup systems

paul j. grimmer , xiaobing xie, carl r. evenson iv ... transport across eltron’s membrane h-h h-h...

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