CO 2 Capture and Fossil Energy Christopher W. Jones Georgia Institute of Technology School of Chemical & Biomolecular Engineering Atlanta, GA Thursday, March 29, 2012

– The earth is warming (about 0.6 ˚C in last 100 years). – Intergovernmental Panel on Climate Change (IPCC): 90% probability that increase in CO 2 concentration in the air is main culprit. – Major source of CO 2 concentration increase is fossil fuel combustion. – Future increases could have catastrophic consequences… or not. – Need carbon mitigation options. Climate and Fossil Fuel Use:

A Problem Created by Chemists & Chemical Engineers: A chemist and chemical reaction engineer who produced the most important scientific discovery 1 of the 20 th century? Who are these people? What was the discovery? 1. V. Smil Nature 1999, 400, 415.

A Problem Created by Chemists & Chemical Engineers: A chemist and chemical reaction engineer who produced the most important scientific discovery 1 of the 20 th century? Who are these people? What was the discovery?  Fritz Haber Nobel Prize, Chemistry, 1918 Carl Bosch  Nobel Prize, Chemistry, V. Smil Nature 1999, 400, 415. N H 2 -> 2 NH 3. Nitrate minerals for fertilizer (Chile): $45/tonne in 1925 $19/tonne in 1937

Energy Demand Growth Dominated by Developing Countries: Source: ExxonMobil

Energy Demand Growth Dominated by Developing Countries: Source: ExxonMobil Year Population Billion Billion Billion Population growth in (relatively) poor zones will drive increased use of cheap (fossil) energy.

How the Energy Demand Will be Met: Source: ExxonMobil Message: Advances in wind and solar energy are desperately needed, but even with tremendous growth…..

How the Energy Demand Will be Met: Source: ExxonMobil Message: Advances in wind and solar energy are desperately needed, but even with tremendous growth, society will continue to rely heavily on fossil energy for the next several decades.

Continued use of fossil fuel in a carbon constrained world will require all of the following: Moderating demand (e.g., by improving energy efficiency). Developing low/no-carbon energy sources. Implementing large scale CO 2 capture and sequestration? Energy Outlook and CO 2 Capture:

Envisioning Widespread Carbon Capture and Sequestration: Source: IPCC, 2005

Separation and concentration require work (energy). Capture and sequestration will cost us energy and money. What is the best we can do? The thermodynamic limit. Base Case Scenario of Energy Cost: Dilute CO 2 mixed in N 2 Separated CO 2 at 1 atm Pressurized CO 2 at 140 atm Pipeline ready ~9kJ/mol ~5% of the output ~13kJ/mol ~7% of the output ~2kJ/mol ~1% of the output Pumping underground and water displacement House et al., Energy Env. Sci. 2009, 2, 193. Post-Combustion Capture from Power Plant Flue Gas:

The Bruce Mansfield Power Plant: 2360 MW electric power generation capacity. 7 million tons coal burned/year. ~41% efficiency million tonnes CO 2 generated per year. 47,800 tonnes/day CO 2 formed (at ~15% vol concentration). 220,000 tonnes flue gas processed per day. The yearly output fits in a 400m cube at sequestration pressures (140 atm). Slide courtesy of Prof. John Kitchin, Carnegie Mellon University.

Post-Combustion Capture Conditions Separation of CO 2 : Flue gas composition after sulfur scrubbing –13-16% CO 2 –4-5% O 2 –6-7% H 2 O –Minor impurities –Balance N 2 Flue gas conditions –60-80°C –10-15 psi Flue gas production rate –A 2500 MW coal plant produces ~550 kg CO 2 /s –~240,000 tons/day of flue gas must be treated Capture goal – psi, dry CO 2 for pipeline ready transport

CO 2 emission sources in the US: Global CO 2 emissions Slide courtesy of Prof. John Kitchin, Carnegie Mellon University. The US has 1493 coal-fired units (400+ plants) –336,000 MW of power generation capacity. –Burn 930 million tonnes of coal/year. –~50% of total US electricity production. –Produced ~2Gt of CO 2 emissions. –Power generation is ~1/3 of the total CO 2 emissions -- Transportation ~1/3, -- Industrial sources ~1/3.

What Would Capture and Sequestration Cost? ~$300 billion dollars/year in electricity sold from coal. At 2 Gt CO 2 /year, if we can manage CO 2 at $30/tonne ~ $60 billion/year in the US. –The $30/tonne has to include all the operating and capital costs associated with CCS. ~$1 trillion/year globally to deal with 30 Gt/year (1-2% GDP). Replacing power capacity with CO 2 -free energy also very $$$.

Envisioning Widespread Carbon Capture and Sequestration: Source: IPCC, 2005

Exhaust from combustion. Key: Amine adsorbent Non-CO 2 flue gas CO 2 Schematic of a CO 2 Capture Process

75˚C Schematic of a CO 2 Capture Process Exhaust from combustion. Key: Amine adsorbent Non-CO 2 flue gas CO 2

Exhaust with 90% CO 2 removed Schematic of a CO 2 Capture Process 75˚C Exhaust from combustion. Key: Amine adsorbent Non-CO 2 flue gas CO 2

Schematic of a CO 2 Capture Process Exhaust with 90% CO 2 removed 75˚C Exhaust from combustion. Key: Amine adsorbent Non-CO 2 flue gas CO 2

Schematic of a CO 2 Capture Process 125˚C Exhaust with 90% CO 2 removed 75˚C Exhaust from combustion. Key: Amine adsorbent Non-CO 2 flue gas CO 2

125˚C CO 2 for sequestration or conversion Schematic of a CO 2 Capture Process Exhaust with 90% CO 2 removed 75˚C Exhaust from combustion. Key: Amine adsorbent Non-CO 2 flue gas CO 2

Questions for Discussion: 1.If CCS costs 1-4% of GDP? Will we do this? Should we do this? What would you do as a policy-maker? 2.Why can’t we simply turn the CO 2 into something useful, on a practical scale? 3.What country should take the lead in implementing CCS? What country do you think is most likely to take the lead in using this technology?

Point Source Capture vs. “Air Capture”: CO 2 Source Properties: Air/Flue Property Air Flue Amount of CO 2 3 teratonnes 20 gigatonnes/yr Distribution 400 ppm - “infinite” mostly uniform source 10-15% point sources Temperature °C Low  T °C High  T – heat integration! Contaminants Low levels of contaminants High levels of SOx NOx, particulates Movement wind, fans fans Two motivations: (i) environmental and (ii) CO 2 source

What is the best we can do? The thermodynamic limit. Base Case Scenario of Energy Cost: Dilute CO 2 mixed in N 2 Separated CO 2 at 1 atm Pressurized CO 2 at 140 atm Pipeline ready ~9kJ/mol ~5% of the output ~13kJ/mol ~7% of the output ~2kJ/mol ~1% of the output Pumping underground and water displacement House et al., Energy Env. Sci. 2009, 2, 193. Post-Combustion Capture from Power Plant Flue Gas: CO 2 Capture from Ambient Air: -- first step is thermodynamically more expensive, the rest is the same. -- for 25-90% CO 2 capture from air, the minimum energy required is 2.6 – 2.9 times more expensive than flue gas capture at 90% capture. -- actual cost = how close to perfect thermodynamic efficiency can be achieved. M. Ranjan, M.S. Thesis, MIT 2010

A review of approaches to extract CO 2 from the ambient air has been written. Supported amine adsorbents are promising materials for the extraction of CO 2 from the ambient air; IF it can be done economically: -- air capture may allow for a “carbon-negative technology” -- account for CO 2 from all emissions sources, including cars, planes -- economics for “environmental applications” currently unknown -- may allow for on-site generation of CO 2 – business development Supported amines offer the advantage of high capacities ( mol CO 2 /kg sorbent) and operation in all humidity levels. Air Capture Conclusions: C. W. Jones Ann. Rev. Chem. Biomol. Eng. 2011, 2,

Air capture may allow for feeding CO 2 to biomass for biofuel production (low concentration) or eventually, CO 2 production for sale (EOR) or sequestration. Air capture should NOT be considered as an alternative to CO 2 capture from flue gas – these are complimentary approaches. Air Capture Conclusions: Photo: NY Times

Global Thermostat: Conflict-of-Interest Statement: Georgia Tech receives research funding from Global Thermostat, LLC, and Jones has a financial interest in Global Thermostat Operations, LLC.

Questions for Discussion: 1.If post-combustion CCS costs ½ of what “air capture” costs, should we pursue CCS? Or air capture? Or both? At what cost should priorities shift to air capture?