James Dennis Kay, 62, from the Heywood area of Greater Manchester, suffered fatal injuries at the Sonae plant on Merseyside.
He was pronounced dead at the scene on Saturday and a post-mortem test into the subcontractor’s death proved inconclusive, Merseyside Police said.
Kay was working for Andrew Connolly Demolition.
Managing director Andrew Connolly told the BBC: “Unfortunately, we can confirm that there has been a fatality of one of our construction workers whilst we were undertaking demolition work at Sonae Industria’s plant in Kirkby yesterday.
“We are extremely saddened by this tragic incident and our deepest sympathies are with his family.
“A full investigation is now under way to establish exactly what happened in the segregated area of the plant that was under our control.”
Kay’s death follows an incident last December when two workers died after falling into a machine at the Sonae plant.
In June, George Howarth, Labour MP for Knowsley, called for the plant to be permanently closed down.
The comments came after a fire the same month caused extensive damage to the site.
Portuguese firm Sonae Industria, which opened the factory in 2000, uses wood chippings in the manufacture of chipboard and particle board.
