About 75 scrap cars went up in smoke after the fire broke out at Recycling Lives on Saturday morning.
Fire crews from Walsall and the surrounding area were called to the site on Tramway Road in Darlaston after the fire had broken out.
The fire had spread among scrap and cars on the site and produced a smoke cloud which could be seen as far away as West Bromwich and Wolverhampton. More than 50 firefighters battled the fire.
Gerry Marshall, CEO of Recycling Lives, was relieved none of his staff were harmed during the fire.
He said: “We are incredibly grateful for the rapid response of the West Midlands Fire Service in quickly containing the fire and that no one was harmed.
“We have as a matter of urgency begun to investigate the cause of the fire and will be liaising with the fire service on this matter.”
Roads near the site were closed off to traffic and cars travelling on the M6 and Black Country Route were forced to reduce speed due to the smoke.