A carbon sink is a natural reservoir that stores carbon-containing chemical compounds accumulated over an indefinite period of time. The process by which carbon sinks remove carbon dioxide (CO
2) from the atmosphere is known as carbon sequestration. Public awareness of the significance of CO2 sinks has grown since passage of the Kyoto Protocol, which promotes their use as a form of carbon offset. There are also different strategies used to enhance this process.The Amazon rainforest’s carbon sink, also known as carbon sequestration, is the process by which the forest removes and stores carbon from the atmosphere.
A carbon dioxide (CO2) sink
- A carbon dioxide (CO2) sink is a carbon reservoir.
- The sinks include forests, oceans, soil and plants and other organisms that use photosynthesis to remove carbon from the atmosphere by incorporating it into biomass.
- Oceans are the largest active carbon sink on Earth, absorbing more than a quarter of the carbon dioxide that humans put into the air
Carbon capture and sequestration is the process of capturing waste carbon dioxide (CO2) from large point sources, such as fossil fuel power plants, transporting it to a storage site, and depositing it where it will not enter the atmosphere, normally an underground geological formation
- The aim is to prevent the release of large quantities of CO2into the atmosphere.
- It is a potential means ofmitigating the contribution of fossil fuel emissions toglobal warming and ocean acidification.
- Although CO2has been injected into geological formations for several decades for various purposes, including enhanced oil recovery, the long term storage of CO2 is a relatively new concept.Carbon Dioxide can be captured out of air or fossil fuel power plant flue gas using absorption (or carbon scrubbing), membrane gas separation, or adsorption technologies.
- long-term storage of carbon dioxide to mitigate global warming & avoid dangerous climate change
- proposed as a way to slow the atmospheric and marine accumulation of greenhouse gases
- Subsurface saline aquifers
Aging oil fields or other carbon sinks
Geological sequestration / storage (Carbon Sink)
The method of geo-sequestration or geological storage involves injecting carbon dioxide directly into underground geological formations for ex :
- CO2 has been injected into declining oil fields for more than 40 years, to increase oil recovery
- CO2 is soluble in oil hence lowers viscosity of the oil & reduces its interfacial tension which increases the oils mobility.
- Salty water contained in deep saline aquifers is not suitable for drinking or agriculture, making saline aquifers an ideal large-scale storage solution for large stationary industrial CO2 emitters.
- Unminable coal seams can be used to store CO2, because CO2 absorbs to the coal surface, ensuring safe long-term storage.
- In this process it releases methane that was previously adsorbed to the coal surface and that may be recovered, & Again the sale of the methane can be used to offset the cost of the CO2 storage