Yes, you can recycle pizza boxes – but only when they’re clean. The corrugated cardboard that pizza boxes are made from is recyclable, but grease contamination can make it unrecyclable. In some cases, the grease may also contaminate other otherwise recyclable products. A diligent recycler will take precautions before putting their pizza box in the recycling.
How Should You Dispose Of Pizza Boxes?
Pizza boxes are just cardboard – so they can be recycled right? Well, yes and no. While the material itself is easily recyclable, the delicious food within makes things a little bit more complicated.
The issue is that the oil contained within the pizza often leaks into the cardboard fibers, making it unrecyclable. Additionally, this oil can leak further into your other recycling, preventing other pieces of card and paper from being recycled. This is called contamination and is a problem for many paper food containers, including paper cups.
If you’re serious about recycling your takeaway pizza boxes, we recommend the following:
Step 1: Remove all solid waste from the box. Don’t leave any bits of pizza or other food in there at all.
Step 2: Cut out any parts of the box that have oil or other food on them. A small smudge is probably ok to leave, but anything more will need to go into the trash. If in doubt, get rid of it.
Step 3: Put the remaining clean pizza boxes into your normal paper and card recycling bins.
The boxes from shop-bought pizza can typically be recycled as with any other box. Because these pizzas are normally stored chilled or frozen and in a plastic wrapping, there should be no contamination. Just chuck them in the recycling like normal – although unfortunately the plastic packaging around the food probably can’t be recycled.
Where To Recycle Pizza Boxes
Uncontaminated pizza boxes can go in your paper recycling. In most countries, this is picked up at the kerbside with your normal collection. If not, look online for your nearest collection point or recycling center.
How Is Corrugated Cardboard Recycled?
Pizza boxes (and other paper products) are recycled using a process known as pulping. The materials are soaked in water to turn them into a pulp which can be then used to make new paper products. Sometimes chemicals are added to speed up the process.
This is where contamination causes a problem. It is hard to separate the oil from the paper fibers; which makes recycling more difficult. Even when the oil does separate out, it doesn’t dissolve in the water (oil and water don’t mix), so it often ends back in the recycled fibers, creating oily marks in the new paper and rendering it unusable.
Recycling companies have to be careful what they accept because contaminated paper can further contaminate other pieces, making the problem worse. This has been made worse because China and other countries (waste is often exported) have become far more careful of what they take and won’t accept items they can’t recycle.
How Quickly Do Pizza Boxes Decompose In a Landfill?
The good news is that the contaminated cardboard will eventually decompose, and in the right conditions this can be quite a quick process. Ideally, the cardboard is shredded and then left in wet and warm conditions, when this is the case it will probably be decomposed within a few months. However, if the cardboard is left densely stacked and dry it can take years.
Clearly, putting old pizza boxes in your trash bin isn’t ideal, but at least it’s better than non-biodegradable plastics. Of course, it’s so easy to recycle your pizza boxes that there shouldn’t really be a reason to put them in the trash.
Can You Put Pizza Boxes In Your Compost?
Yes, pizza boxes can go in your compost, but it needs to be broken up into small pieces first – the smaller the better. If you stick it in as one large piece, it won’t decompose as quickly. For best results, soak the pizza box in plenty of water first. Leftover pizza and contamination is less of an issue because you’re not trying to recycle it, so don’t worry about cleaning out every last crumb of food.
Your pizza box counts as a brown part of your compost, so you’ll also need to make sure there are also plenty of green nitrogen-rich materials – your glass clippings, fruit peel, old vegetables. A 50-50 ratio is probably a good place to start. You might also want to add in a bit of soil to help it get going; soil is full of bacteria that help break everything down.