March 18, 2007

Mar. 18, 2007: Coal technology

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Updated: Mining, Copper-Gold, DRC, Gobi

The Precarious Future of Coal -- A new MIT report says that much more effort is needed to develop and test technology that will make clean-coal power plants economical and practical. , By Kevin Bullis, March 14, 2007

Energy experts from MIT have released a long-awaited report on the future of coal. [....]

The report, based on a study by 13 MIT faculty members, comes at a time when growing concerns about global warming are making it increasingly likely that governments worldwide will impose a price on carbon-dioxide emissions to force a cut in the release of this important greenhouse gas.

[....] The report challenged the idea, argued by some energy experts, that a new type of coal plant--one that converts coal into a gas before burning it--will make it easier and cheaper to capture carbon dioxide, compared with collecting it from the smokestacks of conventional power plants. The MIT experts say that several factors make the picture more complicated. Such coal gasification doesn't work well with low-grade coal, for example, and both the new and the conventional plants will require major changes to capture carbon dioxide, according to the MIT report.

As a result, the MIT researchers recommend that governments not support the new gasification plants over conventional plants.

Part I: China's Coal Future , By Peter Fairley, January 04, 2007

To keep pace with the country's economic growth, ­China's local governments, utilities, and entrepreneurs are building, on average, one coal-fired power plant per week. The power plants emit a steady stream of soot, sulfur dioxide, and other toxic pollutants into the air; they also spew out millions of tons of carbon dioxide. In November, the International Energy Agency projected that China will become the world's largest source of carbon dioxide emissions in 2009, overtaking the United States nearly a decade earlier than previously anticipated. Coal is expected to be responsible for three-quarters of that carbon dioxide.

[....] Gasification transforms coal's complex mix of hydrocarbons into a hydrogen-rich gas known as synthesis gas, or "syngas." Power plants can burn syngas as cleanly as they can natural gas. In addition, with the right catalysts and under the right conditions, the basic chemical building blocks in syngas combine to form the hydrocarbon ingredients of gasoline and diesel fuel. As a result, coal gasification has the potential both to squelch power plants' emission of soot and smog and to decrease China's growing dependence on imported oil. It could even help control emissions of carbon dioxide, which is more easily captured from syngas plants than from conventional coal-fired plants.

Despite China's early anticipation of the need for coal gasification, however, its implementation of the technology in power plants has lagged. The country's electricity producers lack the economic and political incentives to break from their traditional practices.

[....] Direct liquefaction produces more fuel per ton of coal than Fischer-Tropsch synthesis. Experts at the Chinese Coal Research Institute in Beijing estimate that the process captures 55 to 56 percent of the energy in coal, compared to just 45 percent for Fischer-Tropsch. However, direct lique­faction is also far more complicated, requiring separate power and gasification plants to deliver heat and hydrogen and considerable recycling of oil, hydrogen, and coal sludge between separate sections of the plant. And breaking down hydrocarbons to just the right length requires exquisite control of the operating conditions and a consistent coal supply.

Search: Inner Mongolia's coal capital, Erdos

Part II: China's Coal Future -- To prevent massive pollution and slow its growing contribution to global warming, China will need to make advanced coal technology work on an unprecedented scale. , By Peter Fairley, January 05, 2007

Carbon Power ....

Ironically, China's move to a more open economy has hampered efforts to deploy more innovative technologies. [....]

The Yantai power plant was based on integrated gasification combined cycle (IGCC) technology. IGCC plants resemble natural-gas-fired power plants--they use two turbines to capture mechanical and heat energy from expanding combustion gases--but are fueled with syngas from an integrated coal gasification plant. They're not emissions free, but their gas streams are more concentrated, so the sulfurous soot, carbon dioxide, and other pollutants they generate are easier to separate and capture. Of course, once the carbon dioxide--the main greenhouse gas--is captured, engineers still need to find a place to stow it. The most promising strategy is to sequester it deep within saline aquifers and oil reservoirs. [....]

The problem is that IGCC plants still cost about 10 percent to 20 percent more per megawatt than pulverized-coal-fired power plants. (And that's without carbon dioxide capture.) China's power producers--much like their counterparts in the United States and Europe--are waiting for a financial or political reason to make the switch. In part, what's been missing is regulation that penalizes conventional coal plants. And China's environmental agencies lack the resources and power to make companies comply even with regulations already on the books. Top officials in Beijing admit that their edicts are widely ignored, as new power plants are erected without environmental assessments and, according to some sources, without required equipment for pollution control. [....]

Buffett to PetroChina Dissident: You Can Always Sell Your Berkshire Stake Berkshire Hathaway Inc.'s Warren Buffett turned the tables on a shareholder who called on him to sell shares of PetroChina Co. because its government-owned parent operates in a nation accused of genocide. , March 9, 2007

[....] The Berkshire shareholder, Judith Porter, submitted a ballot proposal aimed at forcing Berkshire to divest its stake in PetroChina because of killings in Darfur, a region of western Sudan. Last month Buffett said PetroChina, controlled by China's biggest government-owned oil company, has no influence over the country's business with Sudan because it's merely a subsidiary.

[....] Campaigners such as the Sudan Divestment Task Force, based in Washington, are trying to sway universities, investment companies and state pension plans to pull their money out of companies that do business that directly benefits the Sudanese government. Militias backed by the government have killed more than 200,000 people, according to United Nations estimates. [....]

Search: taught sociology at Bryn Mawr College , business that directly benefits the Sudanese government

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