Carbon capture and storage is a technology that captures almost 90% of the carbon dioxide emissions from power stations and industrial sites. It includes processes such as transporting, collecting and then burying the CO2 so that it can contribute to climate change and can hold it together so that it does not escape into the atmosphere.The process usually does not takes too much time and it is divided and performed with three techniques i.e Pre-combustion, Post-combustion and Stripping out the CO2 released by the process. This carbon capture technology is very efficient for longer use.
It can be further described as the Pre-combustion process involves scrubbing the power plant’s exhaust gas using chemicals. This process takes place before the fuel is placed in the furnace by first converting coal into a clean-burning gas stripping out the CO2 released by the process. The other method, oxy fuel burns the coal in an atmosphere with a higher concentration of pure oxygen.
In the above process, the gas is trapped and the state of the gas is changed and it is liquefied, and then transported for several hundred miles and buried. The last above method is often used in a process called “enhanced oil recovery”, where CO2 is pumped into an oil field to force out the remaining pockets of oil that would otherwise prove tough.
Up to 40% of a power station’s energy could end up being used to run the carbon capture technology scrubbing and transport systems. Some of the oldest power stations may end up being uneconomical to refit.
Below is the detailed explanation of the processes:-
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The technique to scrub CO2 from flue gas without using the two-step process includes using seawater to absorb the gas and after that return the mixture back to the ocean for long-term storage. But at this moment this method has proved less effective.
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In this system, the air pushed into the boiler is turned into liquid oxygen, gaseous nitrogen, argon, and other trace gases and this process can use up to 15% of the power produced at the station.
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This method is generally applied to the coal-gasification combined cycle power plants. To produce a synthetic gas made from carbon monoxide and hydrogen, coal is gasified. The former is then replaced with water to produce CO2. hydrogen is then burned to produce electricity.