CO2 Separation and Sequestration

from Flue Gas with Membranes

Post-Combustion CO2 Capture Workshop Talloires, France

July 11, 2010

Richard Baker

Membrane Technology and Research, Inc.

Menlo Park, California, USA

www.mtrinc.com

� The nature of the problem

� Brief review of membrane gas separation technology

� Membrane-based CO2 capture from power generation

� Where we are now

� The future

2

Outline

1 billion metric tons CO2 = 1 gigaton CO2 > mass of all humans

AtmosphericCO2 concentration

(ppm)

CO2 emissions(billion metric tons)

Source: Oak Ridge National Laboratory, Carbon Dioxide Information Center

Year

Atmospheric CO2 Content is Increasing

3

> 40% of U.S. CO2 Emissions are

Produced During Electricity Generation

� Rules of thumb:Coal � powerOil � transportationNatural Gas � mixed

• 1,100 coal-fired power plants in the U.S.

• 5,000 coal-fired power plants worldwide

• Coal generates 60% more CO2 per MW compared to natural gas

Source:http://epa.gov/climatechange/emissions

4

Coal-Fired Power Plants are Large Point Sources

of CO2 Emissions

BoilerCoal

AirESP FGD

Ash

Steam to turbines

600 MWe plant emits ~10,000 tons CO2/day

• Gas is at atmospheric pressure, contains ~10-13% CO2 and is dirty: fly ash, SO2,Nox, and trace metals are present.

• Several CCS technologies are being considered (absorption, adsorption, membranes)

Sulfur

5

Natural Gas:

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

CO2/CH4, CH4/N2

NGL/CH4

Membrane Technology and Research

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.

6

• Composite membranes are thin to provide useful fluxes.

MTR Uses Composite Membranes

Packaged as Spiral Wound Modules

Each module contains 20 to 100 m2 of membrane7

• Spiral-wound modules

CO2 Capture with Membranes at

a Coal-Fired Power Plant

BoilerCoal

CO2

AirESP FGD

Ash

Steam to turbines

Membrane challenges for treating this large volume of gas include:

• Large membrane area needed • high CO2 permeance is a must!

• How to generate driving force w/o using large compression or vacuum power

• How to handle contaminants

Sulfur

8

• Compressor electricity cost is significantly more than the annualized module replacement cost.

• A two megawatt (2,000 kW) compressor costs $1,000,000 and uses $1,200,000 electricity/y

Membrane plant design as drawn by a plant purchaser

Lessons from the Current Industry

9

10

Vacuum operation uses• Ten times the membrane area• Only 40% of the compression power

Pressure ratio = 10, � = 50, P/�������������� �������������90% CO2 recovery

Compression or Vacuum Operation

Preliminary Conclusions

• Power consumption is the key issue

• The maximum affordable pressure ratio is about 10

• A single-stage process is not going to work

• Vacuum operation is likely the lowest energy design

• Membrane areas will be big � millions of square meters

• A selectivity of 30 to 50 seems optimum

11

• Countercurrent sweep with combustion air provides “free” driving force � lower energy required.

• CO2 recycled in the combustion air stream decreases membrane area required.

• Water in the flue gas helps

The MTR Process

12

Membrane Assisted CO2 Liquefaction and Injection

13

The Total MTR Process –

The Lowest Energy Case

14

15

10

12

14

16

18

20

22

0 1 2 3 4 5 6

90% capture

Fra

cti

on

of

pla

nt

en

erg

y n

eed

ed

(%

)

Membrane area (MM m2)

1.1 bar

1.5 bar

2.0 bar

2.5 bar

3.0 bar

Lowest

cost

case

(a)

Lowest

energy

case

15

20

25

30

35

40

0 1 2 3 4 5 6

90% capture

Ca

ptu

re c

ost

($/t

on

CO

2)

Membrane area (MM m2)

3.0 bar

1.5 bar

2.0 bar2.5 bar

1.1 bar

(b)

Lowest

cost

case

Lowest

energy

case

But millions square meters of membranes are required

Predicted Process Costs Look Attractive

� Total energy use in plant is 56 MW; uses 5.5 MW water pumps

� Plant produces 100 million m3/yr of fresh water

Membrane Plants

of The Required Size Exist Today

Ashkelon desalination plant

� 40,000 spiral-wound RO membrane modules (Dow Filmtec®)

� 1.5 million m2 membrane area

16

Polaris™ Membranes are

Extremely Permeable to CO2

10

20

30

40

50

60

100 1,000 10,000

CO2/N2

selectivity

CO2 permeance (gpu)

PolarisTM

Target area

identified from

design calculations

Commercial

natural gas

membranes

Polaris™ membranes are 10 times more permeable to CO2 than conventional membranes used for natural gas treatment; Pure-gas data at 25 C and 50 psig feed pressure 17

Higher CO2 Permeance Reduces Cost

More Than Higher 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 capture

Pressure ratio = 5.5

Polaris 1 CO2 permeance

Polaris 3

Baseline amine capture cost is >$80/ton CO218

Where We Are Now

APS Red Hawk Power PlantField Test

19

Red Hawk Module Test Unit

MTR is conducting field demonstrations at Arizona Public Service (APS) power plants

Algae Reactors

Red Hawk is a 1060 MWe natural gas-fired power plant located near Phoenix, Arizona

CO2 from Red Hawk plant is sent to algae reactors for biofuel production

20

APS Cholla Power Plant Feasibility Test

� Six-month test with coal-fired flue gas started in April 2010

� Polaris™ membrane system captures 1 ton CO2/day

21

Planned Future Development

Cholla II skid (20 ton CO2/day or 1 MWe) is proposed to begin operation in late 2011

22

23

High Permeance Membranes in

Low Cost Membrane Modules and Housings are Key

0

10

20

30

40

50

60

70

80

0 1,000 2,000 3,000 4,000

CO2/N

2selectivity

CO2 permeance (gpu)

Feed = 50 psig and 25°C

2006

baseline

Red Hawk

2008

Cholla I

2009

Cholla II

developmental

membranes

Membranes are getting better

DOE Post-Combustion CO2 Capture Timeline

Cholla I (1 ton CO2/day)�Collaboration with APS and EPRI�Demo module performance at Cholla test site

Large Scale Field Testing (100-500 ton/day)

�Utility site

24

2014 2016 2018

Large-Scale Field Testing

5– 25 MWe

Now

Cholla II Demo (20 tons CO2/day)•Babcock and Wilcox will evaluate CO2 recycle idea �EPRI will investigate flue gas water recovery

Thank You