clean 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 sulfur dioxide, and reburned so as to make the carbon dioxide in the flue gas economically recoverable. The coal industry uses the term "clean coal" to describe technologies designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation and use[1], with no specific quantitative limits on any emissions, particularly carbon dioxide. So, it cannot be called clean from an environmental point of view, because it is carbon emitter.

The burning of coal, a fossil fuel, is one of the principal causes of anthropogenic climate change and global warming . The concept of clean coal as a solution to climate change and global warming is claimed to be "greenwash" by some environmental organizations such as Greenpeace[2] because emissions and wastes are not avoided, but are transferred from one waste stream to another. The Australian of the Year, paleontologist and environmental activist Tim Flannery made the assertion that "Coal can't be clean"[3].

There are no coal-fired power stations in commercial production which capture all carbon dioxide emissions, so the process is theoretical and experimental and thus a subject of feasibility or pilot studies. It is has been estimated that it will be 2020 to 2025 before any commercial-scale clean coal power stations (coal-burning power stations with carbon capture and sequestration) are commercially viable and widely adopted.[4]. This time frame is of concern because there is an urgent need to mitigate greenhouse gas emissions and climate change to protect the world economy according to the Stern report. Even when CO2 emissions can be caught, there is considerable debate over the necessary carbon capture and storage that must follow.

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 sulfur dioxide (SO2), nitrogen oxides (NOx) and particulate (PM) emissions from the coal-burning process, carbon dioxide (CO2) emissions and radionuclides [5] will be more difficult to address. Technologies do exist to capture and store CO2, but they have not been made available on a large-scale commercial basis due to the high economic costs[6]. For this reason renewable energy sources or nuclear power may be a more cost-effective and environmentally friendly alternative.

Potential uses of clean coal

Examples of clean coal usage include the proposed US FutureGen plant — planned to be a near zero-emissions coal-fired power plant, but is still years away from commercial operation (expected 2012) and whose commercial viability is unknown.

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. These 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. The return of the coal chute and its 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 already used to convert methanol or gasoline to the natural gas form.

Potential cost of clean coal

In Carbon capture and storage under "Cost of CCS" lifetime costs for natural gas, pulverized coal and IGCC with and without carbon capture are detailed.

In a study conducted in 2003 by the IEA GHG, "the capital cost of building a Shell-designed IGCC could cost $1371 per kW-electric without carbon capture and $1860 with it."[7]

Comparisons with other energy sources can be found in Economics of new nuclear power plants.

Support

Clean Coal has been mentioned by United States President George W. Bush on several occasions, including his 2007 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."[8].

In Australia, clean coal is often referred to by Opposition Leader Kevin Rudd as a possible way to reduce greenhouse gas emissions [2]. Current Prime Minister John Howard believes that nuclear power is a better alternative, as clean coal technology may not prove to be economically favorable [9].

Criticism

Prominent environmentalists including 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". [10] Complaints focus on the environmental impacts of coal extraction, high costs to sequester carbon, and uncertainty of how to manage end result pollutants and radionuclides. There are other viable forms of clean and renewable energy such as solar, wind and hydroelectric which are supported by the many environmentalist groups and campaigns. One of the newest strategies deployed is the Big Switch. [11]

See also

External links

Industry Articles on Clean Coal

Steven Edwards, Senior Vice President and Managing Director Americas Region, Black & Veatch Steven F. Leer, President and CEO, Arch Coal, Inc. Mark O’Neill, Executive Director, Australian Coal Association Ron Wood, President, Energy Engineering & Construction Division, Black & Veatch

Reference notes

1. ^ AustralianCoal.com.au - Clean Coal Overview
2. ^ GreenPeace.org - Clean Coal Myths and Facts
3. ^ Herald Sun, Melbourne Australia February 14, 2007 04:30pm
4. ^ David Brockway, Chief of the Energy Technology Division, CSIRO, quoted by Crikey.com.au 20 Feb 2007
5. ^ ORNL.gov - Coal Combustion: Nuclear Resource or Danger?
6. ^ BBC.co.uk - Clean coal technology: How it works
7. ^ Parliamentary Office of Science and Technology (2005). Cleaner Coal. Retrieved on 2007-04-23.
8. ^ Remarks of Senator Hillary Rodham Clinton to the Cleantech Venture Forum VIII
9. ^ NineMSN.com.au - Interview: John Howard February 11, 2007
10. ^ Grist.org - Coal Position
11. ^ The Big Switch - Australia's largest community climate change campaign
Coal (IPA: /ˈkəʊl/) is a fossil fuel formed in swamp ecosystems where plant remains were saved by water and mud from oxidization and biodegradation.
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A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties.
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Gasification is a process that converts carbonaceous materials, such as coal, petroleum, or biomass, into carbon monoxide and hydrogen by reacting the raw material at high temperatures with a controlled amount of oxygen.
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In physical chemistry, and in engineering, steam refers to vaporized water. It is a pure, completely invisible gas (for mist see below). At standard atmospheric pressure, pure steam (unmixed with air, but in equilibrium with liquid water) occupies about 1,600 times the
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Sulfur dioxide (also sulphur dioxide) is the chemical compound with the formula SO2. This important gas is the main product from the combustion of sulfur compounds and is of significant environmental concern.
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Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state.
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Flue gas is gas that exits to the atmosphere via a flue, which is a pipe or channel for conveying exhaust gases from a fireplace, oven, furnace, boiler or steam generator. Quite often, it refers to the combustion exhaust gas produced at power plants.
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Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state.
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4, 2
(mildly acidic oxide)
Electronegativity 2.55 (Pauling scale)
Ionization energies
(more) 1st: 1086.5 kJmol−1
2nd: 2352.6 kJmol−1
3rd: 4620.5 kJmol−1

Atomic radius 70 pm
Atomic radius (calc.
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Emission generally means sending something out. It very commonly refers to flue gas or exhaust gas resulting from the combustion of fuels in a fireplace, oven, furnace, boiler, steam generator, gas turbine, automotive internal combustion engines, rocket engines and other equipment.
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Fossil fuels or mineral fuels are hydrocarbons found within the top layer of the earth’s crust. They range from very volatile materials with low carbon:hydrogen ratios like methane, to liquid petroleum to nonvolatile materials composed of almost pure carbon, like
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Anthropogenic effects, processes, objects, or materials are those that are derived from human activities, as opposed to those occurring in natural environments without human influences.
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Climate change refers to the variation in the Earth's global climate or in regional climates over time. It describes changes in the variability or average state of the atmosphere over time scales ranging from decades to millions of years.
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Global warming refers to the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation.

The global average air temperature near the Earth's surface rose 0.74 ± 0.18 Â°C (1.33 ± 0.
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Climate change refers to the variation in the Earth's global climate or in regional climates over time. It describes changes in the variability or average state of the atmosphere over time scales ranging from decades to millions of years.
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Global warming refers to the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation.

The global average air temperature near the Earth's surface rose 0.74 ± 0.18 Â°C (1.33 ± 0.
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Greenwash (a portmanteau of green and whitewash) is a term that is used to describe the actions of a company, government, or other organization which advertises positive environmental practices while acting in the opposite way.
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Greenpeace

Founded 1971, Vancouver, BC, Canada
Area served Global
Focus Environmentalism
Method Nonviolence, Lobbying, Research, Innovation
Website www.greenpeace.org

Greenpeace was founded in Vancouver, British Columbia, Canada in 1971.
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There are many waste streams consisting of a number of waste types. These are produced by a variety of processes. Each waste type has different methods of associated waste management.
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Timothy Fridtjof Flannery (born 28 January 1956) is an Australian mammologist, palaeontologist and global warming activist. Flannery was named Australian of the Year in 2007 and presently an adjunct professor at Macquarie University.
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The Stern Review on the Economics of Climate Change is a 700-page report released on October 30, 2006 by economist Nicholas Stern for the British government, which discusses the effect of climate change and global warming on the world economy.
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Carbon capture and storage (CCS) is an approach to mitigating global warming by capturing carbon dioxide (CO2) from large point sources such as power plants and subsequently storing it instead of releasing it into the atmosphere.
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Particulates, alternatively referred to as particulate matter (PM), aerosols or fine particles, are tiny particles of solid or liquid suspended in a gas. They range in size from less than 10 nanometres to more than 100 micrometres in diameter.
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Renewable energy utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. Renewable energy technologies range from solar power, wind power, and hydroelectricity to biomass and biofuels for transportation.
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Nuclear power is a type of nuclear technology involving the controlled use of nuclear fission to release energy for work including propulsion, heat, and the generation of electricity.
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Motto
"In God We Trust"   (since 1956)
"E Pluribus Unum"   ("From Many, One"; Latin, traditional)
Anthem
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This article or section contains information about a planned or expected power plant.
It may contain information of a speculative nature and the content may change dramatically as the construction and/or completion of the power plant approaches, and more information becomes
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A power station (also referred to as generating station or power plant) is an industrial facility for the generation of electric power.[1][2][3]

Power plant
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A microbial fuel cell (MFC) or biological fuel cell is a bio-electrochemical system that drives a current by mimicking bacterial interactions found in nature. Micro-organisms catabolize compounds such as glucose (Chen, et al.
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