Process — How waste paper is recycled into new paper

The diagram illustrates the sequence of stages by which paper that has already been used is turned back into usable paper.

Overall, the procedure consists of seven distinct stages, beginning with collection and ending with finished reels of paper. What is most notable is that the process is cyclical rather than linear: once the new paper has itself been used, it re-enters the sequence at the first stage.

In the opening phase, waste paper is collected from households and offices, after which the different grades are separated by hand and by machine and any card is taken out. The sorted paper is then pulped, that is to say mixed with water and chemicals in a large tank until it breaks down. This pulp is forced through a series of screens so that staples and glue can be removed, before printing ink is lifted to the surface by air bubbles and soap.

In the second phase the clean pulp is converted back into sheets. It is sprayed onto a moving belt, where it is pressed and heated until it dries out. The paper produced in this way is finally cut into reels and returned to shops for sale, at which point the loop begins again.