Mixed waste is collected at these plants. At each plant, two sieves are used to separate the waste into size fractions. At
one plant, the openings in the sieves have a diameter of 40 mm and 100 mm to create fractions of 0–40 mm, 40–100 m and >100 mm
At the second, the sieves are 20 mm and 80 mm, to give fractions of 0–20 mm, 20–80 mm and >80 mm. The 0–40 mm fraction was manually sorted to create a 20–40 mm fraction. Thus, in the present study, these fractions were used: 0–20 mm, 20–40 mm, 20–80 mm and 40–100 mm.