Carbon Capture Utilisation and Storage

 Carbon Capture Utilisation and Storage 

Carbon capture Utilization and storage (CCUS) is an attempt to remove carbon dioxide from the atmosphere after burning gas, oil, coal or biomass. The technology can capture the carbon and use it wisely whenever there are important ways to do so. This technology could play a diverse role in meeting global energy and climate goals.

Why carbon needs to stored ?

Carbon emissions have continued to grow at an average of 1 to 2% per year over the past 81 years. If this trend continues into 2050, we will reach a point where our emitted carbon has reached 60 billion metric tons. Across all these years, the carbon emission ranged from 4.25 billion tons to 37.12 billion tons—which is 873.5% in total! Can you imagine living without oxygen? The world would be filled with only Carbon Dioxide gas evolving around us - lots of environmental pollution, along with unpredictable climate changes and natural disasters could occur as a result。

To achieve a more stable and healthy environment, the United Nations has enacted several policies designed to reduce carbon emissions. These agreements were signed in Paris at the end of 2015, with the goal of bringing atmospheric levels of CO2 down to zero by 2050. This is known as "Net Zero" energy production - meaning that we would generate as much renewable energy as needed to offset our own emissions every year. It's an ambitious but achievable goal!

Are we stick with our goals and moving towards it ? Might be Yes ! Might be No !. We will discuss this in our upcoming articles.

Carbon Capture Utilization and Storage

Various Industries uses various technologies to capture the carbon. But the Foremost and commonly used technics are only two they are ,

• Point Source Carbon Capture
• Direct Air Capture

Point source carbon capture

Point source carbon capture is the process of capturing CO2 emissions before they are released into the atmosphere. It is a pre-emissive technology , that is the carbon is captured before the emission. The Flue gas is harnessed from the Factory chimney, its between 100-165 degrees. Since the temperature is very high it needs to be cool down to 30 degrees. This process happens in a direct contact cooler, the temperature is reduced and Caustic soda (NaOH) is added to remove sulfur dioxide and hydrochloric acid from the flue gas and the cooled flue gas then goes to the bottom of the absorber. Then the solvent is injected in the other side of the absorber. The CO2 molecules in the flue gas react with solvent. The solvent which use for carbon capture is Mono ethanol amine(MEA). Mono ethanol amine has the tendency to combine with carbon , that is the carbon is easily attracted and combines with Mono ethanol amine. The rest of the flue gas without the content of CO2 it again pass back to the chimney. This MEA and CO2 combination is termed as rich amine solution, consists of only carbon and MEA. Then this rich amine is pumped into a desorber where the mixture is heated to about 120 degrees .This thermal cracking breaks the bond between the MEA and CO2. Then the CO2 is compressed for utilization and storage.

pictorial representation of point source carbon capture

Direct Air Capture(DAC)

Direct Air Capture is  a technology that uses the chemical reaction to pull carbon dioxide out of the air. It is a post-emissive technology that is the carbon is captured after the emission process. The key advantage of this technology is it can be placed anywhere, irrespective of industries. If some area is highly polluted we can simply place this technology there. It is not mandatory to place this technology in nearby Industries.

Big Fans are used to suck large amount of polluted air directly out of the atmosphere. Behind the fan, the carbon absorbent material is placed to absorb the carbon. In DAC, PVC sheets are used to absorb the carbon. PVC sheets acts as a filter too. Every single surface inside the stack is wetted with carbon dioxide absorbing solution. In most cases, Amine solution is used. Air containing CO2 flows over the surfaces and when CO2 molecules encounter the liquid then converted into carbonate. The Geometry of the packing material ensures that much of the liquid is possible is exposed to the passing air. It also disturbs the flow creating turbulence , so most of the air streaming through actually makes contact with the solution. The net result, the Carbon dioxide is trapped in solution for further processing.

        Scenarios behind the fan

                  pictorial representation of direct air capture

Storage and Utilization

When comes to storage , both Point source method and Direct Air capture method stores in a similar way. The Captured CO2 is sent to the reservoir/ sea beds through pipelines, it can be stored for several years and after that time period these CO2 gas converts into minerals. This is where the CO2 is well utilized.

In order to produce synthetic fuels, captured carbon must be stored in special equipment. Once this carbon is captured, it can then be used in food processing or combined with hydrogen to create synthetic fuel. In a transition towards net-zero emissions, the use of CO2 for producing synthetic fuel will increasingly require capture from sustainable bioenergy sources or from the atmosphere. In Industry applications, Captured CO2 is used as an enhanced oil recovery method



Do you ever wonder why carbon is the most important factor for climate change? After all, oxygen and nitrogen make up nearly 99% of the atmosphere. So why are these two elements not considered as important when it comes to climate change?

 Click here to find the answers