It seems easy, but it is not. Paper layer makes up 75% of the carton packaging. The paper part is what can be recycled relatively easily The recycling mill puts the cartons in a large vat of water where the cartons are agitated. As the cartons rub against each other, the fibers are rubbed apart and dissolve into the water. The end result is paper pulp which can then be reused for tissue or other paper products like cereal boxes.