1. CO2 Capture Status & Issues
Prof. Mohsen Assadi
Gas technology

2. Outline Background Capture technologies & status Post-combustion
Pre-combustion
Oxy-fuel

3. Electricity generation

4. New plant capacity (VGB)

5. Capture ready plants Not well defined! Place & performance!
Post-combustion most suitable for future “capture ready” plants
Large steam extractions needed for regeneration
Minimum pre-investment for steam turbine

6. Various capture technologies

7. Amine Scrubbing Advantages Proven technology Known chemical process
Ability to predict performance and solvent consumption
Limitations
High energy consumption for solvent regeneration
High rate of process equipment corrosion
High solvent losses due to fast evaporation
High degradation in presence of oxygen

8. Existing plants

9. Existing plants

10. Pilot plants

11. Status No full scale plants in operation yet
More research and development needed
Scaleable, flexible pilot plants for validation & verification

12. Chilled Ammonia (1.6 C) Advantages
Lower regeneration energy with HP regeneration
Low-temp. CO2 absorption min. NH3 emissions.
High CO2 absorption efficiency in bubbler absorber.
Applicable for new plants and for retrofit
Carbonates are stable over a wide range of temperatures & do not degrade during absorption-regeneration
The process uses low-grade waste heat
Potential to capture 90% of CO2 emissions

13. Chilled Ammonia Limitations Ammonia volatility can be an issue.
The pH of the ammonia solvent does not allow for much carbonate formation.
Slower absorption rate than MEA. Requires three times more packing to achieve the same CO2 removal performance. A number of absorber vessels are required, increasing capital cost and affecting plant layout.

14. Status
2 MWe field pilot to be operated at the Pleasant Prairie Power Plant, Wisconsin, US
Pilot plant under construction at Karlshamnsverket, Sweden

15. Oxy-fuel
Advantages
Exhaust gases consist of CO2 & H2O. Separation by condensation.
Very low NOx emissions
Efficient O2 separation reduces efficiency penalty (AZEP, membrane)
Limitations
Expensive air separation process with high energy demand (Cryogenic)
New development of gas turbines needed
CO2 recirculation for temp. control
Condensation process needs new equipment

16. Status High oil prices provide a market for EOR
An old GT (TIT 780C) will be modified (CO2 Global, Carl W. Hustad)
Experiences to be transferred to modern GTs
KMB-project in Stavanger (UiS & IRIS)