There are three basic processes for reducing CO2 levels in flue gases generated by fossil-fuel (coal, lignite or natural gas, for example) power stations.
These are post-combustion capture, pre-combustion capture, also known as IGCC (integrated gasification combined cycle), and the oxy-fuel process. All three are important steps in developing green energy sources.
However, we do not yet have a mature solution for the disposal of CO2.
One method currently on trial is sequestration, i.e. CO2 storage below the ground or seabed, either in crude oil or natural gas reservoirs, saline aquifers or coal seams. This is part of the carbon capture and storage (CCS) process chain, which extends all the way from CO2 separation to final disposal, which is making an important contribution to sustainable energy production.
However, the CO2 sequestration step is still in developmental stages. Under the umbrella of the CO2MAN (formerly CO2SINK) project, Linde is participating in investigations into technologies capable of pumping CO2 into plutonic rock over long periods of time. Linde is also involved in a further pilot project investigating the use of carbon dioxide to increase natural gas recovery rates (enhanced gas recovery, or EGR).
