The problem of gas, self-burn, dust management and increasing rate of recovery should be attended.

进行放顶煤开采时，应注意瓦斯、自燃、粉尘的治理及提高回收率等问题。

youdao

The problem of gas, self-burn, dust management and increasing rate of recovery should be attended.

进行放顶煤开采时，应注意瓦斯、自燃、粉尘的治理及提高回收率等问题。

youdao