Tuesday, July 24, 2012

Want to know about Clean Coal?

I am posting a copy of the synthesis paper I wrote on Clean Coal Technology for my English 111 course. This is for those like me who have heard the term "clean coal" mentioned in conversation or the media but really have no idea what it means. My paper is not by any means all-inclusive or perfect. (I am only learning to write and to put my thoughts to paper, so please bear with me.) There is still much research to be done. I simply offer a generalized understanding of the subject. I encourage you to take the time and explore this topic on your own and to develop your own opinion of clean coal.
*Oops seems my paper lost it's format when I copy and pasted.  I believe you will still be able to follow along though. *

Clean Coal Technology

What can Americans do to reduce our carbon footprint? Some suggest a new energy technology, clean coal, is the answer. Others claim the carbon capture and storage process could have dangerous effects on our environment. Here you will find information to help you make an educated opinion on the topic at hand. The information covered will include: clean coal technologies/processes, how these technologies could affect our environment, and what the technologies could do for our economy.

First, we will discuss the term “clean coal technology.” Many of us have heard the term used either in conversation or in the media. But how many of us actually know what the term means? Author, S. Sen (2011), tells us in his article An Overview Of Clean Coal Technologies II: Mitigating The Environmental Impacts By Continuous Improvement In Coal Combustion and CCS Technology, that the term “clean coal technologies” came about as a way to describe the technologies being used to make coal a more environmentally friendly energy source (p. 118).

While the Clean Air Act of 1970 has resulted in lower sulphur dioxide and nitrogen oxide emissions (Sarkus, 2008, p. 8), carbon dioxide emissions remain high. With the growing concern over global warming, many environmentalists are demanding that something be done to cut the emissions of the dangerous greenhouse gas, carbon dioxide. Coal emits a great deal of carbon dioxide when it is burned. And according to Steve Miller (2011), President and CEO of American Coalition of Clean Coal Electricity, “nearly half of our nation’s electricity is generated by coal” (p. 2). If coal is one of the largest carbon dioxide producing energy sources and half of our electricity is generated in coal-based power plants, just how much carbon dioxide does the U.S. emit in a year? According to a report located near the end of Thomas A. Sarkus’(2008) article Fossil Energy, Clean Coal Technology, And FutureGen, carbon dioxide emissions in the United States equal 6.3 billion tons per year. The report goes on to give us an illustration: “1 million metric tons of CO2:
Every year would fill a volume of 32 million cubic feet
Close to the volume of the Empire State Building” (p. 7). Now let us take into consideration the words of Steve Miller (2011) from his article, Coal: A Key Part Of Our Clean Energy Future, “America’s recoverable coal reserves exceed those of any other country and represent one-quarter of the world’s total coal supply” (p. 2). Miller (2011) goes on to explain that America’s reserves equal 272 billion tons and are expected to last close to 250 years (p. 2). It is then understandable why there is such a determination to create an environmentally friendly process for our greatest domestic energy source.

We look to Thomas Sarkus, Director of Project Financing & Tech Depl. Division at National Energy Technology Laboratory, U.S. Dept. of Energy, for information regarding current methods of producing coal electricity in the U.S. and an explanation of how the carbon capture and storage (CCS) process works. Currently, the United States employs the following types of coal-based power plants: pulverized coal (PC), fluidized bedcombustion (FBC), and integrated gas combined cycle (IGCC) (Sarkus, 2008, p. 3). While the Department of Energy (DoE) supports all three of these types of plants, the DoE is primarily interested in combining the efforts of the more efficient IGCC plant with the carbon capture and storage (CCS) process (Sarkus, 2008, p. 3). “The integration technologies- the gasifier with the combined cycle with the air separation presents a technological challenge” (Sarkus, 2008, p. 3). In other words, the process of combining the IGCC plant with the CCS process is still new and there are still kinks to work out before the combined system could reach it’s maximum efficiency. Currently, such a power plant does not exist in the United States, however, plans for one are underway. “In February 2003, President Bush announced FutureGen, a government-industry partnership to prove the near zero emissions concept for coal-based electric power generation” (Sarkus, 2008, p. 6). In the carbon capture and storage (CCS) process, carbon dioxide is produced in a concentrated stream and then separated from other emissions during the coal burning process. Once the carbon dioxide is captured , it moves into the storage part of the process, also sometimes referred to as “sequestration” (Sarkus, 2008, p. 3). Sandstone and saline formations under the earth’s surface are a couple of the proposed geologic carbon dioxide storage sites (Sarkus, 2008, p. 3).

In the article Underground Coal Gasification: Another Clean Coal Option,” senior editor for POWER, Angela Neville (2011), explains how the Underground Coal Gasification (UCG) process works. The UCG process works by drilling boreholes into the coal seam and installing a UCG module, which is made up of two underground wells. One is an injection well and the other is a production well (p. 2). “Air and/or oxygen is introduced to coal while it is still in the ground” through the injection well. Syngas is then formed and pumped to the surface via the production well (Neville, 2011, p. 2). UCG would eliminate the need for the traditional open pit and underground coal mining processes. While CCS is fairly new, the UCG process has been around a little while. “Much of the work nowadays is in refining the techniques to increase efficiency and reduce costs, rather than in overcoming major technical challenges” (qtd. in Neville, 2011, p. 3). UCG is not a common process in the U.S., but there is a pilot project underway in Rawlins, Wyoming (Neville, 2011, p. 10). There are, however, UCG plants in other countries we can look to for expectations in environmental challenges, estimated costs, and life expectancies of plants. While the UCG project at Chinchilla, Queensland, Australia was only in operation for two years, the Uzbek UCG company has operated “the world’s oldest UCG project at Angren, Uzbekistan… for more than 40 years” (Neville, 2011, p. 8).

Now that we have a basic idea of the clean coal technology processes, let us take a look at the environmental challenges these processes may produce. Since the UCG process has been around a little longer and we have a better understanding of how it works, let us look at it first. The environmental challenges related to the UCG process are: “groundwater contamination, subsidence, surface contamination, and gas emissions” (Neville, 2011, p. 6). Groundwater contamination can be avoided by selecting an appropriate site (Neville, 2011, p. 6). Subsidence is a typical environmental challenge in relation to coal production, however because the coal is never removed from the ground and traditional mining practices are not used, subsidence issues should be relatively low. Surface contamination is evident in most any production process. If the right steps are followed, this should not be a major environmental concern. And finally, gas emissions “are essentially no different than from any other industrial process using coal” (Neville,
2011, p. 7). However, the potentially successful outcome of the CCS technology partnered with the UCG process could let us see UCG projects take off quickly (Neville, 2011, p. 8).

 Because the CCS process is fairly new and not currently employed on a large scale, the environmental challenges are not as clearly defined. One of the main concerns with the CCS technology has to do with the sequestration part of the process. Will the carbon dioxide stay underground once it is stored there? “At Statoli’s Sleipner East gas field in the North Sea, CO2 is separated from natural gas and re-injected into a deep saline formation” (Sarkus, 2008, p. 6). “Statoli has been injecting 1 million tons of CO2 per year since 1996” (Sarkus, 2008, p. 6). “The Sleipner cap rock is working effectively” (Sarkus, 2008, p. 6). Sandstone and saline formations are not the only proposed geologic storage areas for the sequestered carbon dioxide. Some of the other suggested locations are: ocean sequestration, “oil reserves, depleted gas fields, and un-minable coal seams” (Sen, 2011, p. 122). Carbon dioxide storage has been used in North America and Europe with success in oil and gas reserves (Sen, 2011, p. 123). However, “consequences of direct CO2 injection into the ocean have not been studied over large ocean areas and for long time periods” (Sen, 2011, p. 122). But “it is believed that the most significant environmental impacts are related to the reduction in the PH value of oceans” (Sen, 2011, p. 122). Groundwater contamination is also a concern for some.

Now, let us discuss what coal and clean coal technology does and could do for our economy. Sarkus and Miller make some bold statements concerning coal and our economy. Miller (2011) claims, “As our nation’s largest source of domestically produced fuel, coal is essential to rebuilding our economy and protecting U.S. jobs, while keeping electricity reliable and affordable for our families and businesses” (p. 2). Sarkus (2008) keeps his statement short and sweet, “Coal is the reason this nation has affordable electricity” (p. 2). Coal production provides jobs- jobs for the miners, transporters and those working in coal-based power plants just to name a few. According to Phaedra Friend Troy (2010), author of Clean COAL Creates Emerging Job Market, the FutureGen “project is expected to create a thousand jobs to the community supporting FutureGen 2.0 and another thousand jobs for the suppliers across Illinois” (p. 2). While the IGCC and CCS process of the FutureGen plant will still employ traditional miners, what would happen to those mining jobs should the U.S. start to employ the UCG process as a main production method for coal electricity? While it would create new jobs, how many others would be lost in the process? There are also concerns of electricity rate hikes due to the need for companies to invest in these new technologies. By 2015, electricity providers are expected to invest “between $115 billion and $125 billion in clean coal technologies to reduce air emissions” (Miller, 2011, p. 2). While this money will likely create jobs, it will also be likely to raise electric rates.

There is still much to be learned about clean coal technology, but I hope I have given you a sufficient overview of the topic.

Miller, S. (2011). Coal: A Key Part of Our Clean Energy Future. Power, 155(8), 88.
Neville, A. (2011). Underground Coal Gasification: Another Clean Coal Option. Power, 155(7), 36-42.
Sarkus, T. A. (2008). FOSSIL ENERGY, CLEAN COAL TECHNOLOGY, AND FUTUREGEN. Coal Age, 113(7), 56.
Sen, S. S. (2011). An Overview of Clean Coal Technologies II: Mitigating the Environmental Impacts by Continuous Improvement in Coal Combustion and CCS Technology. Energy Sources Part B: Economics, Planning & Policy, 6(2), 118-125. doi:10.1080/15567240903567647
Troy, P. (2010). Clean COAL Creates Emerging Job Market. Power Engineering, 114(12), 6-7.

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