Clean coal technology

From Wikipedia, the free encyclopedia

Main article: Coal

Clean coal is the name attributed to coal chemically washed of minerals and impurities, sometimes gasified, burned and the resulting flue gases treated with steam, with the purpose of almost completely eradicating sulphur dioxide and reburned so as to make the carbon dioxide in the flue gas economically recoverable. The carbon dioxide can then be captured and stored instead of being released into the atmosphere (see carbon capture and storage).

1 Byproducts
2 Potential uses of clean coal
3 Support and opposition
4 See also
5 External links
- 5.1 Industry Articles on Clean Coal
6 Reference notes

[edit] Byproducts

The byproducts of clean coal are very hazardous to the environment if not properly contained. This is seen to be the technology's largest challenge, both from the practical and public relations perspectives.

While it is possible to remove most of the sulphur dioxide (SO2), nitrogen oxides (NOx) and particulate (PM) emissions from the coal burning process, carbon dioxide (CO2) emissions will be more difficult to address. Technology does exist to capture and store CO2 but they have not been made available on a large-scale commercial basis due to high economic costs^[1].

[edit] Potential uses of clean coal

The primary example of clean coal is the proposed US FutureGen plant — a zero-emissions coal-fired power plant.

It is also believed that some process similar to the natural gas fuel cell or microbial fuel cell (charged from biomass or sewage) may be practical using coal as fuel. Those technologies are used mostly for stationary fuel cells as charging is slow. A large power plant in a coal mine might be the most energy efficient approach and require the least transport of coal to the users, though the return of the coal chute and use in homes may be possible in some places, especially if home sewage or natural gas lines can be tapped as well by an improved fuel reformer technology such as that used already to convert methanol, gasoline to the natural gas form.

[edit] Support and opposition

Clean Coal has been mentioned by United States President George W. Bush on several occasions, including his latest State of the Union Address. Bush's position is that clean coal technologies should be encouraged as one means to reduce the country's dependence on foreign oil. Senator Hillary Clinton has also recently said that "we should strive to have new electricity generation come from other sources, such as clean coal and renewables."^[2].

Despite the supportive comments from U.S. President Bush about clean coal, the White House has only granted $18 million (USD) to develop zero-emission coal-fired power plants over the next decade out of a $388 billion omnibus spending bill. ^[3]

In addition, some prominent environmentalists (such as Dan Becker, director of the Sierra Club's Global Warming and Energy Program) believe that the term clean coal is misleading: "There is no such thing as 'clean coal' and there never will be. It's an oxymoron". ^[4] Complaints focus on the the environmental impacts of coal extraction, the prohibitively high costs to sequester carbon, and uncertainty of how to store end result pollutants.