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  Carbon Sequestration  Process of Carbon Sequestration: Carbon sequestration is a process of the geological storage of carbon dioxide. Used in this way, it is considered a non-biological process in which carbon is captured and stored away from the atmosphere where it can have negative impacts and add to global warming effects. Carbon sequestration is seen as a geo-engineering process because the Earth's environment is deliberately being changed to alter the effects of global warming. (image from []) There are two steps to carbon sequestration: the "capture" step and the "sequestration", or storage step. In order to capture the carbon dioxide from the air, it must be separated from the other gases surrounding it. Once the carbon is captured, which is mostly pure, it must be stored in a permanent place.

In the image above you can see the natural gas entering the power station. There the natural gas is separated into the carbon dioxide and the usable hydrogen. The hydrogen enters a power station where it is used to make electricity and lets off a by-product of water (H20). The carbon dioxide, instead of being deposited into the power station and being burned into the air, is sent into an underground storage site where it can be stored and is able to allow more oil to be captured, that could not have been captured before. Under layers of rock the carbon dioxide is not able to penetrate and re-enter the air. At this deep pressure the carbon dioxide can become a liquid and mix with the salty water that is deep beneath the surface of the Earth.

(Image from: []) media type="youtube" key="OtfuYlhDjw4" height="364" width="445"

Above is a video from the National Technology Laboratory (NETL) that is operated by the U.S. Department of Energy. The NETL is a group that helps advance the U.S.'s economic, national, and energy security. This video summarizes the need and process of carbon sequestration. Here is a link to the NETL website: []  Importance of Carbon Sequestration to Climate Change: Global warming is a process in which the Earth’s air and oceanic temperatures gradually increase. Light from the sun passes through the atmosphere and heats the planet. Some heat leaves the atmosphere while some of it stays within the atmosphere. As levels of greenhouse gases like carbon dioxide increase, the Earth’s atmosphere may trap more and more heat. This increase in heat will increase the Earth’s average temperature and may change weather patterns. The effects of global warming are becoming more of a concern to our world with each passing day. Warmer temperatures bring more infected insects that migrate north. These insects carry deadly diseases, like malaria, and also plague. Stronger and more frequent hurricanes are occurring and also extreme drought and heat waves. Melting ice caps can cause numerous chain-linked problems; the economy of world civilizations will also be negatively affected. Essentially, global warming is a crisis that needs to be resolved as quickly as possible. This is where carbon sequestration comes into play. (image from [] ) Through the process of carbon sequestration, carbon dioxide can be captured from large contributing sources emitting carbon dioxide like fossil fuel power plants, and can be captured from the air. This would decrease the amount of carbon dioxide in the atmosphere, which in turn would allow more heat to escape, so the temperature of the Earth will not continue to increase. (Image from:http://redgreenandblue.org/2008/07/16/epa-drafts-rule-for-carbon-sequestration/) The image above is of a power plant in the UK that provides about 7% of the UK's energy. It is one of the most efficient coal-fired power plants in the UK, but still is a large carbon dioxide producer. Although in the photo above a large amount of the smoke stack in the image is water vapor, it is mixed with carbon dioxide as well. This particular plant emits about 22.8 million tons of carbon dioxide and 1.5 million tons of ash each year. (Statistics found at []).

The U.S. Energy Information Administration predicts that the U.S. will emit 7,550 million tons of carbon dioxide by 2030, and increase by14% from 2005. It is necessary that the amounts of carbon dioxide are lowered, and carbon sequestration is necessary to do so.

Instead of creating new energy, carbon sequestration cleans up the coal that the world uses. The Chemistry of Carbon Sequestration: Capturing carbon dioxide from the air can be difficult because carbon dioxide molecules contain oxygen, so capturing large amounts of carbon dioxide would result in a decrease of oxygen in the air. Carbon dioxide from the combustion of coal in oxygen is mostly pure, so it can be processed directly. In other instances, such as air capture, there is a "scrubbing" process to purify the carbon dioxide. This process is harder to complete because there are other toxins mixed with the carbon. There are three ways to remove the carbon dioxide: 1) post-combustion 2) pre-combustion and 3) oxyfuel combustion. 1) __Post-combustion:__ This is where the carbon dioxide is removed after the combustion or burning (an exothermic reaction between a fuel and oxidant that produces heat or light) of the fossil fuel. This is the method used in power plants. The carbon dioxide is removed from the flue gases (the gases trying to get into the atmosphere) after the reaction. This process includes the scrubber systems to make sure there is pure carbon being stored. 2) __Pre-combustion:__ This is where the fossil fuel is partially oxidized, like in a gasifer in one of the images above. The fossil fuel being oxidized is the gasifer before combustion, which pulls off the carbon emissions allowing the carbon dioxide to be captured before the combustion of the fossil fuel takes place. 3) __Oxyfuel combustion:__ This is where the fuel is burned in pure oxygen instead of air. In this reaction the flue gas consists of carbon dioxide and water. The water vapor is separated by condensation and the carbon dioxide can then be easily stored in a sequestration site. (Image from h[|ttp://www.battelle.org/Environment/publications/EnvUpdates/Fall2005/article4.stm])

//Now that we know the types of carbon capture, how is it actually captured?//

Great amounts of pressure can dissolve carbon dioxide in water. This is impractical because it would take a lot of energy to create this pressure. It is more practical that a catalyst, something added to a reaction to speed up the reaction but does not change the substance's identity, is used. The catalyst used in speeding up the separation of carbon dioxide and water is a protein enzyme called carbonic anhydrasel (CA). This enzyme is used in photosynthesis in plants and maintaining blood pH in animals. The enzyme would be able to convert carbon dioxide into bicarbonates. This can then be stored underground against alkaline rocks, which will neutralize the carbon. This method is one possible way of going about capturing the carbon, although it is not the only method being used.

(Image from [|www.renewacycle.com/ 2007/02/5.html])

Video from: [] media type="youtube" key="QYT-0-UI7xw" height="364" width="445"

Credits: Process of Carbon Sequestration: **By- Emily Brown** Importance of Carbon Sequestration to Climate Change: **By- Caitlyn Metsack** Chemistry of Carbon Sequestration: **By- Emily Brown** Edited by: **Caitlyn Metsack** Citations: " Carbon capture and storage -." __Wikipedia, the free encyclopedia__. 08 Mar. 2009 .  __DOE - National Energy Technology Laboratory: Home Page __. 08 Mar. 2009 . "To Make Amends for Emissions, Businesses Try Offsets; Some Companies Are Buying Compensation for Emissions They Can't or Won't Eliminate." __The Christian Science Monitor__ 8 Jan. 2007. 8 Mar. 2009. "5 Deadliest Effects of Global Warming: Global Warming Effects, Causes of Global Warming and Effects on Global Warming." __Environmental Graffiti__. 17 Mar. 2009 .