A Crash Course on Carbon Capture
The general consensus from the IPCC is that carbon capture technology will be essential to the rebalancing of carbon gasses in our atmosphere. As temperatures increase globally, it’s important for us to look around and ask why? With our current emissions, even these higher temperatures are not sustainable. Even the most optimistic projections predict that expected carbon dioxide emissions will lead to over 2 °C of warming worldwide. As industrial factories, gas powered vehicles, and constant methane from animals continue to pump carbon into the atmosphere, we must act quickly to counter this. Now although there have been many efforts to reduce emissions, with our current state of production being fueled by fossil fuels and other carbon emitting fuels, that is an unrealistic task. So, the timely arrival of another method has been much appreciated. One to finally push the world into carbon neutrality and a more recyclable world: Carbon Capture.
What is Carbon Capture?
Carbon capture uses one of two methods to extract CO2: direct air capture or precombustion. With direct air capture, an array of large fans is set up to suck in a bunch of air into a specialized set of filters. Once the filters reach full capacity, they are moved and heated to reveal a highly concentrated CO2 gas. With precombustion, a similar method is used. Instead of relying on large fans to draw in the CO2, the filters are attached directly to the place of emissions. However, no matter the method, carbon capture in essence is fairly flexible and mobile, as facilities will work anywhere you set them up. For example, a carbon capture system set up in Argentina will be able to offset emissions from China.
The idea for carbon capture is one that has been around for a long time. In fact, the first carbon capture facility was proposed in 1938. In the early 1970s at a gas processing facility in Texas, CO2 was captured and piped to a nearby oil field to boost oil recovery. Enhanced Oil Recovery, as it was then known as, was proven to be very successful. Since then, both from natural accumulations of CO2 in underground rocks and captured from industrial facilities are now piped to oil fields all around the world as a means to boost oil recovery. However it wasn’t until the mid 1990s that Sleipner launched the world’s first integrated carbon capture and storage project in Norway. Sleipner was the world’s first commercial CO2 storage project which produced fuel with up to 9% CO2, however, in order to meet the required export specifications and the customers requirements, it was to be reduced to 2.5%. Over time, this number will continue to drop, and Enhanced Oil Recovery will continue to be a better option for storing energy.
Currently there are a series of paths for Carbon Capture utilization and storage. Essentially anything that has any connection with carbon can be used for carbon capture storage. The cost of carbon capture ranges anywhere from $350/ton for low density Direct Air Capture to $15/ton for better natural gas refining practices. These prices should continue to decrease, similar to how the cost of solar panels continued to go down over the past 20 years. That said, one of the main issues with carbon capture is what to do with the carbon dioxide stored. It’s not economically incentivized just to store carbon away, and as a result there will be less of a push to start working on this problem.
The current problem with our climate is the abundance of CO2 in the atmosphere. Many scientists believe that in order to save our planet from the imminent threat of global warming, we must lower our emissions across the board. However, that is not realistic. With most of the innovations that make our lives better comes more emissions of greenhouse gasses. You cannot decrease the quality of people’s lives without resistance. So the solution, carbon capture, aims to balance out the emissions by extracting the CO2 directly from the air. But the question that is then posed is what to do with the waste product?
Carbon capture is, at its core, a physical problem of acquisition and storage. However, current solutions utilize carbon capture as a chemical process, taking advantage of the chemical properties of carbon to create a better storage and use material. There are multiple options for carbon to be utilized, but these are the most prominent:
H2 and N2 use
Material Production (Graphene, plastics, etc.)
Hydrogen Gas is a promising alternative as a fuel, considering the chemical strength and spark that hydrogen brings to a combustion source. Currently there are a series of hydrogen production avenues, which each correspond to a color that they showcase.
Both gray and brown hydrogen are derived from hydrocarbons, making it a carbon positive system and adding carbon dioxide into the environment. Blue hydrogen utilizes the same processes, but makes the system carbon neutral by storing and capturing the carbon dioxide released. Given the cost of carbon capture, this could be a cheaper alternative to green hydrogen, as brown and gray hydrogen are magnitudes cheaper than green at this current moment. Blue hydrogen is currently being tested, but at this moment it is neither economically nor environmentally viable to produce.
Carbon Capture could also go directly into Nitrogen capture. Certain microbes are able to oxidize hydrogen to ‘upgrade’ ammonia and carbon dioxide into fuel for themselves, which then allow them to be used as feed for fish or soy. Utilizing carbon and ammonia (NH3) to create a strong food source for farms across the nation allows a carbon negative solution for large factory food production.
What Does Carbon Capture Create?
Carbon is also a major component of any fuel, as it’s literally in the name hydrocarbon. A hydrocarbon is a combination of solely carbon and hydrogen atoms to create a highly potent fuel. When burned, these fuels release energy, but the actual atoms rearrange into CO2 and water. The burning of oil, coal, and natural gas have created these issues of fuel, but there may be a way to turn this in the other direction. Plants have consistently used the technique of turning CO2 and water into fuel for both themselves and the environment around them, and there may be a way to do this ourselves.
Replicating this process has had some varied results. The stage we are currently at is turning CO2 into syngas, which is a combination of hydrogen, carbon dioxide, and carbon monoxide. It’s not at the fuel stage right now, but there’s a potential to actually get gasoline from CO2. This, however, is not carbon negative. In a perfect scenario this is completely carbon neutral, but the actual process to take all this energy and create an organic compound will require a lot of carbon given our current infrastructure.
When extracting CO2 from the air, oftentimes carbon capture plants will sort it out into pure carbon. When flattened into a sheet with a width of one carbon atom, this pure carbon can be made into graphene. This sheet of carbon, called graphene, is currently a very expensive and rare material that is extremely valuable for its properties. It’s a very hard material, it can generate electricity when exposed to light which makes it the perfect candidate for solar panels, it is virtually invisible, it is highly conductive and can be shaped into carbon nanotubes, it consumes less energy compared to other materials, it is very flexible and malleable, it has high thermal conductivity, and much more. If carbon capture facilities were to focus on producing graphene, the world could move to a much more efficient place with quicker computers, more solar panels, and many more advantages.
One of the most costly systems of carbon emissions is the creation of cement, as it accounts for around 8% of the world’s carbon emissions. This is everything from sand mining to transportation to mixing. Given this massive amount of carbon, this could be a potential for taking carbon and creating a sink that won’t leave the system. A carbon sink is just a system that can take in carbon without releasing it in an easy way. Just as a sink can hold water well without releasing it, a carbon sink can hold carbon without emitting it. The way this would work is through using materials from captured carbon to create cement, such as sand with carbon capture technologies and carbon neutral mixing.
For carbon capture facilities that are not interested in turning a profit from what they produce but are rather more interested in storing the carbon, artificial stone is their best option. The CO2 that is captured is dissolved in water and injected deep underground, where it turns into stone overtime. This process helps eliminate the CO2 in the air rather than simply recycling it.
Using stone for carbon capture is an example of sequestration, which is the process of storing carbon for a long period of time. A large amount of carbon goes through the carbon cycle of changing and manipulating the form of CO2 into things like sugars in food, oil, and so on.
Enhanced Oil Recovery
The oil industry actually does benefit from some forms of CO2 capture. A better, cleaner CO2 can be used to create a better oil production process. The injection of CO2 and water can be used to essentially push out oil wells into pipes. Right now, these productions go through deep rock formation to both push out oil, but also to sequester carbon. Check this presentation out for more details.
Natural Carbon Capture
A more natural form of carbon capture comes in the form of plant life. Trees, algae, and even moses take in CO2 naturally as part of photosynthesis. The outcome is reduced carbon in the atmosphere and an oxygen output.
Carbon capture facilities have essentially been “rooted on” by the government as their climate friendly agendas are very popular amongst those looking to offset carbon emissions. In the United States, companies must pay a certain “Carbon Tax”. Under a carbon tax, the government sets a price that emitters must pay for each ton of greenhouse gas emissions they emit. This incentivises companies to cut down on emissions to lower expenses. Currently, the carbon tax is fifty United States dollars per ton of emitted CO2.
However, more recently the Biden administration embedded a pro-carbon capture proposal within its $1.75 trillion spending package that would enable carbon capture facilities to become eligible for an $85 credit for each ton of CO2 captured and stored. This is a $35 increase from the current price.
Companies Currently In Carbon Capture
Climeworks is a Swiss carbon capture company which passionately believes in global warming as a current threat. Their methodology of removing CO2 is largely centered around combatting this issue and storing excess CO2 in the ground. Their first direct air capture plant launched in 2017 and has since grown to 15 operating machines. One of the facilities, based in Iceland, was named the world’s first large-scale plant. Climework’s plants store CO2 in stone or convert it into raw materials that can be used for various purposes later on. With Climework’s main mission being negative emissions, they regularly work with and encourage businesses to rebalance their CO2 output.
Earthly Labs is a system used to target emissions from smaller businesses and homes. They pitch a start to finish system, with capture hardware, software, and installation all done through their processes. Currently, their pitch is with CiCi, transforming a mixed gas stream (containing impure CO2) to a high quality CO2, which can be used in beverages, a fire extinguisher, a refrigerator, or food preservation.
This field is not one that is going to stop anytime soon. The risk of climate change is too high for everything to not be tried, and this is a fairly solid set of solutions to look into. Carbon is everywhere in our life, and if we are able to manipulate it fully, then we are able to solve many of the world’s problems, even past climate change. We can help with material shortages, making manufacturing easier and better. We can help with biological problems, with the efficient production of drugs and medical devices. Everything around us is carbon, and through this system of Carbon Capture Utilization and Storage, we can help build a better, cleaner future for future generations.