The Massachusetts Institute of Technology - netl.doe.gov Library/Events/2012/CO2 Capture... ·...
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What Does E-MAR Do? Why Do We Need E-MAR? E-MAR, or Electrochemically-Mediated Amine Regeneration, is an entirely new way of performing the desorption and regeneration steps for amine scrubber systems that remove carbon dioxide, CO 2 , from industrial flue gases. Traditionally, desorption has been achieved through heating the amine working solution with steam until the CO 2 is released. The solution’s CO 2 sorption capacity is regenerated in a heat exchanger before the solution returns to the absorber. The heart of the E-MAR system is an electrochemical cell, which performs both the desorption and regeneration of the loaded amine solution under isothermal conditions using targeted electrical energy instead of heat. Thermal-swing absorption systems have been unable to meet the efficiency required for carbon capture and sequestration (CCS) to be an economical method of mitigating CO 2 emissions. E-MAR has several advantages over traditional thermal scrubbing systems: • Direct application of energy for CO 2 release − No energy used to heat water • High desorption partial pressures of CO 2 − Compressor duty can be reduced by 50% • Drop-in downstream configuration for easy retrofitting − No rearrangement of the steam turbine chain • Double the per cycle utilization of amines − Novel desorption strategy allows for near zero loading in lean stream E-MAR offers the advantages of an advanced amine scrubbing system with the flexibility of an electrically-based system. How Does E-MAR Work? Absorption Regeneration e ‐ Copper Electrode (Anode) Copper Ion CO 2 -loaded Amines (From Absorber) Copper Ion Amines Complex Released CO 2 Bubbles Compression & Sequestration Electrons to Cathode Desorption Unbound Amines Flue Gas CO 2 -loaded Amines CO 2 -Lean Flue Gas To the atmosphere To the Desorber (Anode) To the Regenerator e ‐ Cathode Chamber Anode Chamber Electrode Separator Copper Electrode Copper Electrode Flash Tank Absorber CO 2 Output Lean Flue Gas Lean Sorbent Rich Sorbent Flue Gas CO 2 Removal Using E-MAR In the absorber, unbound amine molecules contact the flue gas and remove about 90% of the CO 2 before releasing the lean flue gas out the stack to the atmosphere. The CO 2 loaded amine solution then goes to the desorber. In the desorber, the copper cathode is oxidized dissolving copper ions into the working solution. These ions then bind with the CO 2 loaded amines and release the CO 2 . The complexed amine solution then goes to the regenerator. In the regenerator, the complexed amine solution contacts the copper anode. The anode is reduced causing the copper ions to electroplate onto the surface. The unbound amines then return to the absorber to capture more CO 2 . Copper Ion Amines Complex (From Desorber) Copper Ion Unbound Amines Copper Electrode (Cathode) Electrons from Anode Back to the Absorber Voltage Source Michael C. Stern 1 , Fritz Simeon 1 , Kristin Vicari 1 , Michelle Barber 1 , Harald Landes 3 , Thomas Hammer 3 , Howard Herzog 2 , T. Alan Hatton 1 1 Department of Chemical Engineering, MIT, Cambridge MA 2 MIT Energy Initiative, MIT, Cambridge, MA 3 Siemens AG, Corporate Research & Technology, Erlangen, Germany The full scrubbing process consists of a gas absorber in series with the E-MAR system. The amine-based working solution cycles between the two units. The main energy input comes from the voltage source powering the electrochemical cell. Pumps and other small auxiliaries are not shown. + + The Massachusetts Institute of Technology: Taking Charge of Carbon Capture E-MAR in the Real World Power Supply Pump Cell Flash Tank Absorber A bench-scale E-MAR system capable of capturing 40 sccm of carbon dioxide has been constructed and is being tested at MIT. Initial results have demonstrated proof of concept. Carbon dioxide is bubbled through an amine solution until saturated. Over 93% desorption of the carbon dioxide is achieved through the injection of copper ions into the CO 2 saturated amine solution. 0 0.5 1 1.5 2 0 50 100 150 200 CO 2 Loading (mol/mol Diamine) Time (min) CO 2 Injection Copper Ion Injection
Transcript of The Massachusetts Institute of Technology - netl.doe.gov Library/Events/2012/CO2 Capture... ·...
What Does E-MAR Do? Why Do We Need E-MAR? E-MAR, or Electrochemically-Mediated Amine Regeneration, is anentirely new way of performing the desorption and regeneration stepsfor amine scrubber systems that remove carbon dioxide, CO2, fromindustrial flue gases.
Traditionally, desorption has been achieved through heating the amineworking solution with steam until the CO2 is released. The solution’sCO2 sorption capacity is regenerated in a heat exchanger before thesolution returns to the absorber.
The heart of the E-MAR system is an electrochemical cell, whichperforms both the desorption and regeneration of the loaded aminesolution under isothermal conditions using targeted electrical energyinstead of heat.
Thermal-swing absorption systems have been unable to meet the efficiency required forcarbon capture and sequestration (CCS) to be an economical method of mitigating CO2emissions. E-MAR has several advantages over traditional thermal scrubbing systems:
• Direct application of energy for CO2 release− No energy used to heat water
• High desorption partial pressures of CO2− Compressor duty can be reduced by 50%
• Drop-in downstream configuration for easy retrofitting− No rearrangement of the steam turbine chain
• Double the per cycle utilization of amines− Novel desorption strategy allows for near zero loading in lean stream
E-MAR offers the advantages of an advanced amine scrubbing system with the flexibility ofan electrically-based system.
How Does E-MAR Work?Absorption Regeneratione‐
CopperElectrode (Anode)
Copper Ion
CO2-loaded Amines (From Absorber)
Copper IonAmines
Complex
Released CO2Bubbles
Compression & Sequestration
Electronsto Cathode
DesorptionUnboundAmines
Flue Gas
CO2-loadedAmines
CO2-Lean Flue Gas
To the atmosphere
To the Desorber(Anode)
To theRegenerator
e‐
Cathode Chamber
Anode ChamberElectrode Separator
Copper Electrode
Copper Electrode
Flash Tank
Abs
orbe
r
CO2 Output
LeanFlue Gas
Lean Sorbent
Rich Sorbent
Flue Gas
CO2 Removal Using E-MAR
In the absorber, unbound amine molecules contact the fluegas and remove about 90% of the CO2 before releasing thelean flue gas out the stack to the atmosphere. The CO2 loadedamine solution then goes to the desorber.
In the desorber, the copper cathode is oxidized dissolving copperions into the working solution. These ions then bind with the CO2loaded amines and release the CO2. The complexed amine solutionthen goes to the regenerator.
In the regenerator, the complexed amine solution contactsthe copper anode. The anode is reduced causing thecopper ions to electroplate onto the surface. The unboundamines then return to the absorber to capture more CO2.
Copper IonAmines Complex(From Desorber)
Copper Ion
UnboundAmines
CopperElectrode (Cathode)
Electronsfrom Anode
Back tothe Absorber
Voltage Source
Michael C. Stern1, Fritz Simeon1, Kristin Vicari1, Michelle Barber1, Harald Landes3, Thomas Hammer3, Howard Herzog2, T. Alan Hatton1
1Department of Chemical Engineering, MIT, Cambridge MA 2 MIT Energy Initiative, MIT, Cambridge, MA 3Siemens AG, Corporate Research & Technology, Erlangen, Germany
The full scrubbing process consists of a gas absorber in series with the E-MARsystem. The amine-based working solution cycles between the two units. Themain energy input comes from the voltage source powering the electrochemicalcell. Pumps and other small auxiliaries are not shown.
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+
The Massachusetts Institute of Technology:Taking Charge of Carbon Capture
E-MAR in the Real World
Power Supply
Pump
Cell Flash Tank
Absorber
A bench-scale E-MAR system capable ofcapturing 40 sccm of carbon dioxide has beenconstructed and is being tested at MIT. Initialresults have demonstrated proof of concept.
Carbon dioxide is bubbled through an amine solutionuntil saturated. Over 93% desorption of the carbondioxide is achieved through the injection of copper ionsinto the CO2 saturated amine solution.
0
0.5
1
1.5
2
0 50 100 150 200
CO
2 Loa
ding
(mol
/mol
Dia
min
e)
Time (min)
CO2 Injection Copper Ion Injection
