Carbon sequestration is the long-term carbon storage in plants, soils, geologic formations, and the ocean.
Types of Carbon Sequestration
Terrestrial Carbon Sequestration:
It is the process through which CO2 from the atmosphere is absorbed by trees and plants through photosynthesis and stored as carbon in soils and biomass (tree trunks, branches, foliage, and roots).
Geologic Carbon Sequestration:
CO2 can be stored, in oil reservoirs, gas reservoirs, unmineable coal seams, saline formations, and shale formations with high organic content.
Ocean Carbon Sequestration:
Large volumes of CO2 are absorbed, released, and stored by the oceans. This can be accomplished in two ways: by increasing the productivity of ocean biological systems by iron fertilization, or by pumping CO2 into the deep sea. The dumping of iron encourages phytoplankton formation, which leads to increased photosynthesis by these microorganisms, which aids CO2 absorption.
Methods of Carbon Sequestration
NATURAL
It is the process by which nature has achieved a balance of carbon dioxide in our atmosphere suitable for sustaining life. Animals expel carbon dioxide, as do plants during the night.
Nature provided trees, the oceans, the earth, and animals as carbon sinks or sponges. All organic life on this planet is carbon-based and when plants and animals die, much of the carbon goes back into the ground where it has little impact on contributing to global warming.
ARTIFICIAL
It refers to a number of processes whereby carbon emissions are captured at the point of production (e.g. Factory Chimneys) and then buried.
One proposed method is ocean sequestration whereby carbon dioxide is injected deep into the ocean, forming lakes of CO2. In theory, the CO2 will stay down deep due to the pressure and temperature of the surrounding water, gradually dissolving into that water over time.
Geological sequestration
The method of geo-sequestration or geological storage involves injecting carbon dioxide directly into underground geological formations like –Declining oil fields, Saline aquifers, and Unminable coal seams.
For more than 40 years, CO2 has been injected into depleted oil fields to boost oil recovery. Because CO2 is soluble in oil, it lowers the viscosity and lowers the interfacial tension, increasing the oil’s 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.
Because CO2 seeps into the coal surface, unmineable coal seams can be used to store CO2. This ensures safe long-term storage. This procedure releases methane that had been adsorbed to the coal surface and could be recovered, and the sale of the methane could be used to balance the expense of CO2 storage once again.
