The slag from power plants is a mixture of the remainder of the completely burnt coal and the partly burnt coal, which can neither be used as fuel, nor be used as raw material for cement industry.

燃煤火力发电厂炉渣是燃烧完全的灰烬与燃烧不完全的煤块组成的混合物。

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A hot coal fell out of the fire and burnt the carpet.

一块燃烧着的煤块从火炉里掉出来把地毯烧了。

《牛津词典》

Banned in today's cosmetics, the cancer-causing tar residue can be found in burnt substances and foods such barbecue, coffee, cigarette smoke, and coal tar.

致癌物焦油残渣如今虽禁止在化妆品中使用，但是广泛存在于烧焦的物质和食物中，如烤肉，咖啡，香烟的烟雾及煤焦油。

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Neil Crumpton, FoE Cymru's energy campaigner, said that using the imported LNG was "little better than the emissions from coal burnt in new coal power station technology".

BBC: Criticism of ?800m gas plan

While methane is a cleaner source of energy than oil or coal when burnt, on its own it is an unusually powerful heat-trapping agent -- perhaps 20 times more potent than carbon dioxide.

CNN: Japan warms to 'fire ice' potential