In the traditional old coal-fired boiler technology limited, in the production process of waste residue, waste gas, waste water waste and taste, is energy polluters and governance difficulties.

在传统老式的燃煤锅炉技术有限的情况下，生产过程中废渣、废气、废水三废俱全，是耗能污染大户并且治理困难。

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Large amount of poisonous gas, coal and waste rocks badly influence the safe product for coal mine, and also cause the economic loss to our country.

煤与瓦斯突出产生大量的煤与矸石和有毒的瓦斯气体，严重影响煤矿安全生产，给国家造成或大或小的经济损失。

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Compared with fossil diesel, biodiesel from waste cooking oil, DME from natural gas or coal, and F-T diesel from natural gas have economic competition.

与石化柴油比较，以废弃食用油或泔脚油为原料的生物柴油，以天然气和煤为原料的DME以及以天然气为原料的F—T柴油具有经济竞争力。

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Originally they were derived from coal-tar, the black viscous waste product left over from distilling coal for gas.

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Considering the opportunities to treat gas that would otherwise be flared, to unlock otherwise uneconomic shale and conventional gas fields, and increasing opportunities for biomass, waste and coal conversion, small-scale GTL may well have a significant niche to fill in our emerging energy picture.

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