Sentence:  They pass through Walsall and on to neighbouring Aldridge where they visit a former foundry that was recently converted - "recycled", according to its owners - into the country's largest "materials recovery facility"(<WSD>MRF</WSD>, pronounced "merf"). 
Meaning of the word marked with <WSD> tags:  Materials recovery facility (or "materials reclamation facility", "materials recycling facility", "multi-reuse facility"): a waste recycling plant.