Understanding Carbon Capture Utilization & Storage

Post-combustion capture is a method used to capture carbon dioxide (CO2) emissions generated from the combustion of fossil fuels, such as coal, natural gas, or oil, in power plants or industrial facilities. It is one of the three main carbon capture and storage (CCS) techniques, along with pre-combustion capture and oxy-fuel combustion.

Here's how post-combustion capture generally works:

1. Capture Process: In post-combustion capture, CO2 is captured from the flue gas produced during the combustion process. Flue gas is the exhaust gas that results from burning fuels in a combustion process.

2. Separation: The CO2 is separated from the other components of the flue gas, such as nitrogen, water vapor, and trace pollutants, using various separation technologies. Common separation methods include chemical solvents, adsorption techniques, and membranes.

3. Capture Medium Regeneration: After the CO2 is captured, the capture medium (such as the solvent) needs to be regenerated to release the CO2 for further use or storage. This typically involves applying heat or pressure to release the CO2 from the capture medium.

4. Storage or Utilization: Once separated, the captured CO2 can be either stored underground in geological formations (carbon storage or sequestration) or utilized for various purposes, such as enhanced oil recovery, manufacturing processes, or chemical reactions to produce valuable products like plastics or building materials.

Post-combustion capture is particularly attractive because it can be retrofitted onto existing power plants and industrial facilities without significant modifications to the existing infrastructure. This makes it a potentially cost-effective way to reduce CO2 emissions from existing sources.

However, post-combustion capture processes often require energy-intensive separation techniques, which can increase the overall energy consumption of the plant and potentially impact its efficiency and economics. Researchers and engineers continue to work on developing more efficient and cost-effective post-combustion capture technologies to address these challenges and make carbon capture and storage more viable on a large scale.