scrap heat

例句：

1. 1. The scrap metal is being melted down for reuse.
   废金属正在被熔化用于再利用。
2. 2.The scrap metal recycling industry is crucial for environmental protection.
   废金属回收行业对于环境保护至关重要。
3. 3.The scrap metal recycling process helps to reduce waste and conserve resources.
   废金属回收过程有助于减少浪费并节约资源。