煤经干馏，产生的挥发性物质称煤气，煤气中还带有焦炭汽蒸产生的水煤气。

Coal gas is made by the distillation of the volatile matter from coal with some steaming of the coke to produce water gas.

youdao

煤经干馏，产生的挥发性物质称煤气，煤气中还带有焦炭汽蒸产生的水煤气。

Coal gas is made by the distillation of the volatile matter from coal with some steaming of the coke to produce water gas.

youdao