Pizza boxes and the rules surrounding recycling them continue to change both in Rhode Island and around the United States. Some counties have started to allow pizza box recycling regardless of their condition. The condition of the pizza box is the main problem with recycling. The cardboard itself is obviously recyclable, but the grease and cheese residue is difficult to breakdown. Stickers and coupons on the design of the box can complicate the process as well.
The Providence Journal Trash Tutorial explains when a pizza box may be recyclable.
No major discoloration of the box, no dripping grease, and the grease isn’t covering the entire bottom portion of the box. A few splotches of grease are fine, as are a few spots of sauce.
Per Earth 911, grease and oil are not significant problems in recycling plastic, metal, and glass because those use a heating process. Cardboard and paper, however, are recycled using water. The grease causes an oil to form at the top of the water slurry, and paper fibers are caught in the oil in the process. Basically, the oil causes the process to be contaminated. This is why many food products, such as napkins, paper towels, and paper plates are non-recyclable.
Currently, the Rhode Island Resource Recovery Corporation website reads as follows when asked why pizza boxes are not recyclable;
If the pizza box were totally clean, it would be. The problem is that they seldom are. It is the grease from the pizza that is the problem. If the top of the box is entirely clean, rip it off and place it in your recycling bin, throwing the greasy part in the trash.
The real dilemma comes down to whether people will take the initiative to clean their pizza boxes to ensure they will not contaminate recycling batches. In the past, people have ripped just the clean half (top or bottom) of a pizza box and recycled only that. The grease isn’t going away in pizza, so a compromise or solution needs to be reached if they are to be recycled.
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