SSS 2009-11-05
时间：2019-01-08 作者：英语课 分类：Scientific American(十一)月
That's the sound of clean coal. Well, cleaner coal. A relatively 1 small unit attached to the smokestack at the Mountaineer Power Plant in West Virginia is capturing some 1.5 percent of the carbon dioxide the coal-fired plant would otherwise belch 2 into the sky.
The loud thrum comes from the whirring of fans that cool the flue gas and the jostling of an agitator 3 that keeps things moving in the tower where the reaction to actually capture the CO2 takes place. There’s also the chug of the compressor, which turns the odorless, colorless greenhouse gas into a milky 4 liquid at 1,400 pounds per square inch (psi).
After that it's off to the storage wells where the fluid CO2 is further compressed to more than 2,000 psi and pumped a mile and a half underground where it's injected into the pores between grains of rock in a layer of sandstone laid down some 440 million years ago.
So far so good for the Mountaineer , which cost the utility that owns it more than $70 million to build. But questions remain. What can be done to clean up coal's other problems, like toxic 5 ash residue 6 or the removal of actual mountaintops? Can carbon capture and storage be scaled up to the size necessary？ to capture a significant fraction of the world's greenhouse gas emissions 7 from fossil fuel burning?What will that cost? And will all that CO2 stay put?
After all, as the mayor of the Ohio town across the river from Mountaineer told me: carbon capture and storage sounds all well and good... until something happens.
- The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
- The operation was relatively painless.手术相对来说不痛。
- Hitler's just a self-educated street agitator.希特勒无非是个自学出身的街头煽动家罢了。
- Mona had watched him grow into an arrogant political agitator.莫娜瞧着他成长为一个高傲的政治鼓动家。
- Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
- I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。
- The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
- There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。
- Mary scraped the residue of food from the plates before putting them under water.玛丽在把盘子放入水之前先刮去上面的食物残渣。
- Pesticide persistence beyond the critical period for control leads to residue problems.农药一旦超过控制的临界期，就会导致残留问题。