Development of Membrane Technology for

CO2 Capture at MTR

Tim Merkel

MTR Director of R&D

September 28, 2012Symposium for Innovative CO2 Membrane Separation Technology

Tokyo, Japan

Personal Connection to Japan

2

Koizumi Yakumo (Lafcadio Hearn)

•Lives in Japan 1890-1904

•Teaches in Matsue and Tokyo University

•Translates Japanese stories to English (Kwaidan)

•Was Tim’s great, great, great uncle

Introduction to MTR

3

Japan~8,000 km

Natural Gas:

Petrochemicals: Hydrogen (Refinery): H2/CH4, CO, CO2Propylene/Nitrogen

CO2/CH4, CH4/N2NGL/CH4

MTR designs, manufactures, and sells membrane systems for industrial gas separations

Customers include: BP, Chevron, Dominion Exploration, Ercros, ExxonMobil, Formosa Plastics, Innovene, Sabic, Sasol, Sinopec, Solvay, and Statoil.

Introduction to MTR

4

The Climate is Changing

5

Muir Glacier, Alaska 63 years later

Fossil Fuel Use And Atmospheric CO2Concentration Are Increasing

Slide courtesy of Dr. S. Julio Friedmann, Lawrence Livermore National Laboratory6

How To Cut Emissions: The Wedge Approach

Use multiple CO2 reduction strategies including CO2 capture from large sources8 wedges needed to maintain CO2at 500 ppm (each wedge ≡ 4 billion tons/y CO2)Japan is world leader in CO2emission reductions (Kyoto Protocol 1997)

Source: Pacala and Socolow, Science, 2004

7

Wedges include:• Improved energy efficiency• Alternative energy (wind, solar)• Nuclear power• Efficient biofuels• Conservation of natural sinks• Carbon capture and

sequestration

Rules of thumb:• Coal power• Oil transportation• Natural Gas mixed

5,000 coal-fired power plants worldwideFossil fuel share of electricity generation (IEA WEO 2010):

• 2008 – 75%• 2035 – 71%

Source: International Energy Agency (IEA) (2008), CO2 Emissions from Fuel Combustion, 2008 Edition.

World CO2 Emissions by Sector

Power Plants Generate >40% of CO2 Emissions

All options involve separations where membranes could play a roleTo use membranes effectively, important to understand the process

CO2 Capture Options for Fossil Fuel Power

Membrane advantages: simple passive operation, small footprint, no water or hazardous chemicals used, energy efficient - no steam usedHot syngas cleanup membranes offer potential for process intensification

GasifierCoal

CO2

O2

SyngasQuench

WGSreactors

Steam Steam

ASU

Air

Syngas cooling

2-stageSelexol

CO2comp

Combustionturbine

Syngas reheat

H2

Polymer membranes; CO2

or H2-selective

Membrane reactors; metal

and ceramic membranesH2-selective

Dirty, hotsyngas

Relatively clean, cool syngas

40°C210°C 270°C

35°C

195°C

600°C

50 bar

30 bar

55 bar

150 bar

CO2storage

Increasingly harsh operating conditions

Pre-Combustion CO2 Capture Membranes

AirN2

Can operate warm/hot to reduce the need for heat exchangeCan use nitrogen sweep to maintain permeate fuel gas at turbine pressureWater goes with fuel gas; reduces CO2 dehydration costs

H2-Selective Membranes Offer Advantages

GasifierCoal CO2

O2

SyngasQuench

WGSreactors

Steam

H2 membrane

Steam

ASU

Air

CO2comp

Combustionturbine

600°C 210°C 150-250°C

50 bar55 bar

150 bar

CO2storage

N2 diluent H2 + N2Air

H2-selective membrane advantages:

0.1

1

10

100

1,000

0.1 1 10 100 1,000

Upper bounda

H2 permeance (gpu)

Pure-gasH2/CO2

selectivity

MTR Proteus(mixed gas at 150°C)

PBIb (250oC)

Crosslinked modified

polyimides c

PBI-based d

(mixed gas at 250 oC)

Need Membranes With Good H2/CO2 Selectivity

a) Robeson et al., JMS 320, 390-400 (2008); assumes a 1 μm selective layer.

b) O’Brien K. et al., DOE NETL project fact sheet 2009; assumes a 1 μm selective layer.

c) Low, B.T., et al., Macromolecules 41(4), 1297-1309 (2008); assumes a 1 μm selective layer.

d) Krishnan, G., 2010 NETL CO2 Capture Technology Conference, Pittsburgh, PA and Klaehn, J., et al.,NAMS 2011, Las Vegas, NV.

Figure adapted from: B. W. Rowe et al., JMS 360, 58–69 (2010).

High Temperature Improves Performance

1

10

100

1,000

20 40 60 80 100 120 140 160 180

Pure-gas permeance

(gpu)

Temperature (°C)

H2

CO2

MTR ProteusTM

Permeance Trade-off Plot

0.01

0.1

1

10

100

0.01 0.1 1 10 100 1,000

H2/CO2 selectivity

H2 permeance (gpu)

200 K250 K300 K350 K400 K

297 K

383 K

ProteusTM

Assumes a selective layer thickness of 0.1 micron

Field Tests with Coal-Derived Syngas

The National Carbon Capture Center (NCCC) in Wilsonville, Al allows slipstream testing of pre-combustion and post-combustion capture technologies

1

10

100

1,000

0 5 10 15 20 25

Mixed-gas permeance

(gpu)

Time (days)

CO2

H2

135°C120°C

120°C

135°C

0

5

10

15

20

25

30

35

40

0 5 10 15 20 25

Time (days)

Mixed-gas H2/CO2

selectivity

120°C

135°C

Permeance Selectivity

Tests were conducted at the National Carbon Capture Center (NCCC) run by Southern CompanyThe coal-derived syngas feed contained 780 ppm H2S

Field Tests Show Stable Performance

Process Economic Analysis With DOE/NETL

16

• Collaborated with DOE NETL and WorleyParsons to analyze MTR process

• Comparison made with Case 2 of DOE ‘Bituminous Baseline’ report (GEE Gasifier with 2-stage Selexol)

• Several sulfur handling options considered (co-sequestration, warm gas cleanup, etc); post membrane MDEA selected as low cost

• Membrane process uses 5% less energy and gives a 7% lower cost of electricity compared to Selexol

• Higher membrane H2/CO2 selectivity would help (particularly up to 40, beyond which diminishing returns)

H2-selective membranes have greater potential than CO2-selective membranes for oxy-blown gasifiers because:• They can be operated hot (>100°C) so that syngas cooling/water

KO equipment and syngas reheat/humidification can be reduced or avoided

• They can be swept with N2 available from the ASU to reduce energy requirements

• They send water to the fuel gas, reducing CO2 dehydration costsPolymer membranes are low cost and sulfur tolerant → a huge advantageMembranes are already competitive with absorption, but better selectivity would lower energy use and costNot much data on polymer membranes above 100°C → significant potential to uncover better materials

Pre-Combustion Summary

Generating affordable pressure ratio is the key challenge for membranesLimited use for high selectivity because of pressure ratio limitationsVolumetric flow is enormous; membranes must have high CO2 permeanceSingle-stage membrane process will not give high purity and recovery

Post-Combustion CO2 Capture with Membranes

BoilerCoal

CO2

AirESP FGD

Ash

Steam to turbines

Sulfur

• 600 MWe → 500 Nm3/s = 1,540 MMscfd flue gas• 10 – 15% CO2 in N2 = 10,000 ton CO2/day at low pressure

• Combustion air sweep provides driving force w/o compression or vacuum • Pre-concentrated CO2 decreases membrane area and power required

The MTR CO2 Capture Process

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18 % O2, 8 % CO2

20% CO2

CO2 depletedflue gas

U.S. Patents 7,964,020 and 8,025,715

Promising Membrane Development

1

10

100

1,000

1 10 100 1,000 10,000 100,000

Upper bound (2008)a

CO2 permeance (gpu)

Pure-gasCO2/N2

selectivity

MTR (2008)c

GKSS (2010)e

UT Austin (2006)b

U. Twente(2010)d

a) Robeson et al., JMS 320, 390-400 (2008); assumes a 1 μm selective layer.

b) Lin et al., JMS 276, 145-161 (2006); assumes a 1 μm selective layer.

c) Merkel et al., ICOM 2008, Honolulu, HI.

d) Reijerkerk et al., JMS 352, 126-135 (2010); assumes a 1 μm selective layer.

e) Yave et al., Nanotechnology 21, 395301 (2010); and Yave et al., Macromolecules 43, 326-333 (2010).

RITE, NTNU

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High CO2 Permeance Most Importantto Reduce Cost

Limited affordable pressure ratio reduces the benefit of high selectivity.

0

10

20

30

40

50

0 20 40 60 80 100

Capture cost ($/ton CO2)

Membrane CO2/N2 selectivity

2,000 gpu

1,000 gpu

4,000 gpu

90% CO2 capturePressure ratio = 5.5

PolarisTM 1 CO2 permeance

PolarisTM 3

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1 TPD Test System at NCCC

1 TPD system installed Oct/Nov 2011; continuous operation spring 2012

Module Number Normalized CO2 PermeanceAfter Test

Normalized CO2/N2 SelectivityAfter Test

5839(Cross-flow) 110% 118%

5879(Sweep) 108% 96%

Fresh moduleAfter 45 days

operation at Cholla

Test Results: Modules Are Stable

1 TPD NCCC Results: Stream Compositions

24

• As expected, membrane enriches CO2 by about 6 times in the permeate

• Initial low feed CO2 content due to air ingress

• Most variation in compositions due to daily temperature swings

• Overall, membrane module performance is stable

1

10

100

0 500 1,000 1,500

CO2 content

(%)

Operating time (hours)

Flue gas outage

Analyzermalfunction

CO2-enrichedpermeate

Feed

CO2-depletedresidue

1 TPD NCCC Results: CO2 Capture Rate

• Initially system operating at ~2/3 capacity

• After 1,000 hours, additional modules loaded to increase capture rate to 85%

25

0

20

40

60

80

100

0 500 1000 1500

CO2

capture rate(%)

Operating time (hours)

Flue gas outage

Analyzermalfunction

Next Steps: 20 TPD System

26

• Estimate installation at NCCC in 2nd

quarter 2013• Operate system at NCCC for 6+ months;

at least 3 months of continuous SS operation

• System demonstrates large bundled spiral-wound modules

20 TPD System at NCCC

1 MW

Flue Gas InFlue Gas

Return

0.5 MWepilot solvent

test unit

Picture courtesy of Mr. Tony Wu, Southern Company

27

Future Scale-Up

One module skid, 2500 m2

– Smaller foot print– Low pressure drop– Reduced manifolding– Lower cost

40 modules plant, 100MWe

62 ft44 ft

64 ft

27 ft

5.5

ft

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Sweep operation: Increases the CO2 in the flue gas from 4% to 20% for gas turbinesReduces the quantity of flue gas going into the CO2 capture unit by a factor of 3Hybrid design with absorption avoids the use of compression/vacuum equipment

Other Concepts: Sweep-Assisted Hybrids

Energy and cost constraints limit the practical pressure ratio available; high permeance, modest selectivity membranes are preferred

A large research effort is producing better membranes

Selective recycle is a useful way to pre-concentrate CO2

Membranes can play a role in post-combustion capture, probably in a hybrid system (cryogenic, amine, etc)

Membrane testing is at the small slipstream stage

Post-Combustion Membrane Summary

Acknowledgements

MTR– Xiaotong Wei, Zhenjie He, Karl Amo, Steve White, Haiqing Lin, Meijuan

Zhou, Sylvie Thomas, Richard Baker, Hans Wijmans, Saurabh Pande

U.S. Department of Energy,National Energy Technology Laboratory– Rick Dunst and Jose Figueroa

Southern Company– Tony Wu, Frank Morton, and John Wheeldon

Acknowledgements

Effect of Membrane Properties on COE

• All calculations for 90% CO2 capture

• Design uses minimal feed compression (booster fan only)

• Higher permeance (lower cost) membranes are key to approaching DOE goals

33

30

40

50

60

70

80

90

0 0.01 0.02 0.03 0.04 0.05 0.06

Changein COE

(%)

Permeance-normalized membrane cost ($/m2 gpu)

1st Generation Polaris

2nd Generation Polaris

MEA (DOE Case 10)

DOE Target

AdvancedPolaris

MTR MembraneProcess

(1.2 Bar Feed)

Higher permeance membranes