More and more, recycled and recovered fibre is a staple for making today's environmentally-responsible pulp and paper products. Mills recycle cellulose fibre for all or part of their raw material needs. Recovered paper is either re-pulped and either alone, or in blends with virgin pulp, reborn in a wide variety of paper products. There are several sources of fibre for recycling. About half comes from corrugated containers, gathered from manufacturing plants, shopping malls, department stores and other commercial establishments.
Offices contribute about a quarter, comprising a variety of papers, computer printouts etc.
Old newspapers, mostly from community collection, account for about 15 percent. The balance comes from printers and manufacturing plants. When waste paper arrives at the mill, it has usually been graded and inspected by the dealer who collects it. At the mill, it is re-pulped in large pulpers like enormous mixmasters. Because recyclable paper originates as waste, it may contain various contaminants such as metal, plastic etc.