coal slag

例句：

1. 1. The factory produces a lot of coal slag for the construction industry.
   这家工厂为建筑业生产了大量的煤渣。
2. 2.The coal slag is used as a fertilizer to improve soil quality.
   煤渣被用作肥料，以改善土壤质量。
3. 3. Coal slag is a byproduct of coal mining and can be used as a building material.
   煤渣是煤炭开采的副产品，可以作为建筑材料使用。