coal preparation waste water

例句：

1. 1. The coal preparation plant islocated in the city center.
   煤准备厂位于市中心。
2. 2. The coal preparation process involves a seriesof steps to remove impurities fromraw coal.
   煤准备过程涉及一系列步骤，以从原煤中去除杂质。
3. 3. Thecoal preparation waste water is a significant environmentalissue that needs to be addressed.
   煤准备废水是一个重大的环境问题，需要得到解决。