CO 2 Flue Gas Scrubber Technology Michael Ng University of Texas Department of Chemical Engineering
Background ► Flue gas is exhaust gas that exits to the atmosphere, which come from boilers, furnaces, or steam generators ► CO 2 is a greenhouse gas that contributes to global warming ► There are around 6,000 coal-fired power plants around the world (Imai) ► 55% of global electricity comes from coal as being the fuel source (Imai)
Coal-fired Power Plant From
Post Combustion Technology There are different ways to capture CO 2 with the use of amine solvents: ► Monoethanolamine (MEA) ► Mixture of MEA and methydiethanolamine (MDEA) ► Piperazine/ Potassium Carbonate
MEA Absorber/Stripper Configuration From
Piperazine/ Potassium Carbonate ► Current research done by Dr. Rochelle and graduate students ► Study the thermal properties and kinematics of CO 2 absorption using PZ/ K 2 CO 3 ► Degradation rate of solvent vs. MEA PZ/ K 2 CO 3 degrades at 1.3 mm/hr MEA degrades at 5 mm/hr ► Corrosion
Integrated Gasification Combined Cycle
Economics (CO 2 Capture)
Economics (Costs)
Six Rules to maximize the effectiveness of PC (adapted from Gibbins, Crane, et. Al) ► 1. Add heat to the steam cycle at as high a temperature as possible ► 2. Reject heat from the steam cycle, in the steam extracted for solvent regeneration, at as low a temperature as possible. ► 3. Produce as much electricity as possible from any additional fuel used, consistent with rejecting heat at the required temperature for solvent regeneration. ► 4. Make use of waste heat from CO2 capture and compression in the steam cycle. ► 5. Use the latest solvent developments. ► 6. Exploit the inherent flexibility of post-combustion capture.
Skyonic SkyMine Process
Recommendations ► Pursue post combustion technology Use solvents that do not degrade as fast as MEA (i.e. PZ/ K 2 CO 3 ) ► IGCC has a high capital investment, but allows for high CO 2 recovery
Questions?