Can You Recycle All Cardboard?

Cardboard can be readily recycled into new, high quality products. However, without proper preparation and storage, this process can be more difficult or even impossible – leading to perfectly good materials ending up in landfill.

At SL Recycling, we process 100 tonnes of cardboard each and every week at our Material Recovery Facility. From tipping to collections to the provision of equipment like balers, we design solutions bespoke to your business, with sustainability at their heart.

In this blog, we outline some of the ways in which cardboard’s recyclability can be impacted.

Cardboard is a versatile, environmentally friendly material that can be easily recycled and repurposed for a variety of uses. There are two main types of cardboard used in commercial applications:

• Corrugated Cardboard – two layers of thick cardboard with an extra layer of lower quality, wavy fibre between the sheets, adding strength and structure.
• Paperboard – a thinner, lower quality cardboard which can be made when fibres become too short to make corrugated cardboard.

Though both corrugated cardboard and paperboard are readily recyclable, coatings and contamination can make the material unsuitable. For instance, any dirt, food, tape, glitter, foil, or plastic can contaminate the load, affect the quality of the cardboard, and even jam sorting equipment. Wet cardboard is also unsuitable for recycling, which is why it needs to be stored carefully in a dry place before being collected by your waste management company.

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Cardboard Recycling Process

The cardboard recycling process usually comprises the following key steps:

• Cardboard is sorted and separated from any other materials like string and plastic.
• It is then baled into different grades.
• The cardboard is shredded and crushed into tiny pieces.
• The material is mixed with water and chemicals to break it down into a thick pulp.
• This pulp is mixed with a small amount of pulp made from fresh material.
• The combined pulps go through a number of filters and are chemically and centrifugally treated to remove any last contaminants like tape, plastics, and ink.
• The clean mixture is then pressed out and dried into flat sheets.

Discover the benefits of recycling cardboard >

What Makes Some Cardboard Unrecyclable?

Now we know how cardboard is recycled, let’s explore what can get in the way. Without proper consideration and storage, your cardboard waste may become unsuitable for recycling. Here’s why.

Food & Grease

Any food or food residue should be removed from cardboard before it gets sent for recycling because grease can wreak havoc on a recycling load. It is impossible to separate any oil that seeps into the material from cardboard fibres, but this can severely impact the quality of the new material. Worse, placing cardboard with food in it into an existing load can allow the grease to spread to other pieces of cardboard, making more of the material unsuitable.

Contamination

A variety of different materials can contaminate a cardboard recycling load, including glitter, foil, plastic, paint, and dirt. There are many reasons why these materials may make their way into a load, with one of the most common being tape left behind on shipping boxes, and stitching and staples used in the construction of cardboard boxes. It’s also common for cardboard to be painted, but this can have severe implications for the entire bale if painted cardboard is included.

Moisture

Wet cardboard is not as easily recyclable as dry material because the added moisture can clog sorting equipment, and exposure to elements can weaken the fibres. Though the material is mixed with water and pulped during the process, this crucially only takes place after the material has been sorted. Moisture before this point in the process adds weight to the recycling load – increasing costs for you – and may lower the quality of the new material.

Age of Fibres

Finally, fibre quality also has a part to play, as cardboard is not an infinitely recyclable resource. Every time cardboard is pulped and slurried, the fibres are broken down into shorter, coarser, and stiffer strands – eventually becoming too short to adhere to each other after around 5-7 cycles. This end of life can be postponed through adding virgin wood pulp to the mix, but eventually the quality of the final product will be too degraded, and the old fibres must be discarded.

How to Store & Prepare Cardboard for Recycling

Essentially, preparing cardboard for recycling is about making sure it is clean and in as good a condition as possible. To achieve this, make sure you do the following three things:

1. Remove any contaminants like foil, plastic, tape, glitter, and paint that you can by peeling it off or cutting it out. Remember also to cut out any food residue or grease stains as this kind of contamination can spread.
2. With the tape removed, you should flatten your cardboard boxes and fold them up so they take up less space during storage.
3. Don’t put your cardboard outside until collection day as it might get rained on. Create a space inside to store your cardboard waste so it can stay dry and readily recyclable.

How to Manage Business & Commercial Waste >