An internal smoke alarm and a call for help sent fire engines rushing to Smurfit-Stone Recycling in the 1300 block of Walker Street at about 1:30 p.m.
Arriving firefighters found the structure engulfed in flames and attacked the blaze from ladder trucks positioned at three corners of the warehouse, said Battalion Chief John Clark.
Smoke still drifted toward the nearby Calhoun Expressway two hours later as firefighters continued to soak the smoldering ruins.
No injuries were reported.
The source of the fire remains under investigation, but it's not thought to be intentional, Clark said.
According to its Web site, Smurfit-Stone Container Corporation is a leading manufacturer of paperboard and paper-based packaging, and is a global leader in the collection of recycled paper, a key raw material for its products.
A small crew monitored the warehouse overnight to guard against flare-ups. The roof will be lifted off the warehouse today so that the fire can be completely extinguished, Clark said.