1. Carbon Capture and Sequestration

2. Capturing Carbon dioxide • Capturing and removing CO2 from mobile sources is difficult. • But CO2 capture might be feasible for large stationary power plants and industrial boiler. • Flue gas – Mixture of nitrogen , water vapor and 15 % of Carbon dioxide.

3. Approach to capture CO2 • React the flue gas with chemicals that absorb CO2 and then heat the chemicals to release CO2. • Remove carbon before combustion. Gasifying the coal through the reaction with more oxygen it is possible to produce a mix of CO2. Then CO2 can be captured leaving H2.

4. Approach to capture CO2 • Use pure oxygen to support the fossil fuel combustion. The flue gas is then mostly CO2 and water making it to separate easily. NOTE: But extracting oxygen from air is very expensive and consumes energy and combustion with pure oxygen occur at higher temperature.

5. Sequestration CO2 sequestration is the storage of carbon dioxide (usually captured from the "atmosphere") in a solid material through biological or physical processes.

6. Where to sequester CO2 ? • Inject CO2 into deep sedimentary rock formation. • The wells that produce fossil petroleum. • Deep Ocean

7. Uncertainty in CCS • Slow leakage would lead to climate changing. • Sudden catastrophic leakage is dangerous, and causes asphyxiation. • Not easy to design a well-engineered sequestration. Difficult to find truly impermeable rock. • It is not a complete solution for anthropogenic CO2 • Construction of CCS is not likely to be done quickly. • Energy intensive and the economic cost.