Underground storage of CO2 - page 1
Belgium signed the Kyoto treaty on 29 April 1998 and pledged to reduce the emission of greenhouse gases, such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). It does not turn out be an easy task. If we continue our way of life, considering economic growth and rising mobility, drastic measures will have to be taken if Belgium wants to fulfil its obligations.
Renewable energy sources, such as wind farms, cannot yet produce enough energy to meet our consumption. Nuclear power stations do not provide an ecologically sound alternative and can only be operational during 40 years. Even a sparing use of energy would not lead to a solution, since our energy requirements will only increase. Due to economic growth, lesser yield of renewable energy sources and the disappearance of nuclear power, the production of CO2 will rather increase than decrease in the future.
How to tackle this problem?
At this moment, the removal of CO2 rom the atmosphere is a more achievable goal than turning off the CO2 tap. Nature offers us a first opportunity. Trees and algae are natural cleaners: they absorb the CO2 in the air and release oxygen. One solution would be to have sufficient space to plant the necessary acreage of forest, but Belgium does not have it. Moreover, on a world-wide scale, the intensive cutting down of the tropical forests makes this method even less likely to succeed.
However, men also can remove CO2 from the atmosphere in two ways, i.e. underground or ocean storage. As Belgium has no ocean, the second option is quite out of the question. Remains the underground storage. Carbon dioxide, captured in important production areas, such as power stations and petrochemical industries, is injected high pressure into underground rock.
The storage reservoir's rock must be porous and impermeable, such as sandstone and limestone. These rocks have small holes through which CO2 can penetrate. In order to have CO2 staying underground and not leaking, the reservoir is closed by an impermeable layer.
