Recycling – as much about shape as material!

I recently took a recycling course from Sustain Dane, and was floored at how much I learned in three hours. I thought I knew how to recycle, but I was so wrong. To sum up my take away in one sentence: recycling is just as much about the size and shape of something as it is about the material. If it doesn’t make it through the sorting process correctly, it will be a contaminant (lowering the quality of the final recycled material) or end up in the trash, missing the point of recycling entirely.

Ok, two sentences.

I always wondered how sorting recyclables was done – its super interesting! Check out this video and the below flow chart we made to show what happens in the sorting process. Keep reading to learn more about how each material is sorted by the facilities that handle our recycling, and how we can better help this process work when we recycle. 

Because recycling is something most of us do on a daily basis, and because correctly throwing items into our blue bins is so important to the success of recycling, it is important we learn how our recyclables are sorted, and then apply that knowledge as we hover over the dual trash/recycling bins, trying to decide what to do. Putting refuse into the correct cart in the correct way is the best way to help make recycled materials worth the effort!

Recycling Paper

The first thing pulled out of the stream of recycling is paper, so that’s what we’ll talk about first! This includes paper, cardboard, and those waxy plastic-covered paper cartons. Paper and cardboard gets sorted by being pushed up steep inclines while 3D objects stay at the bottom and get bounced off – so make sure the paper you throw in the bin is 2D, except for cartons, which should be cleaned and thrown in with the lid attached. See our low-down on paper recycling!


The next thing to be pulled out is glass! Glass gets sorted by being crushed and falling away from lighter, uncrushed materials. The main thing to know about glass recycling is that it is limited to jars and bottles. No drinking glasses, vases, windows, or mirrors. See our low-down on glass recycling!


Next up is metal, one of the easiest to recycle materials! Metal is pulled out by magnets and eddy currents, which rely on intrinsic properties of the material itself. However, you need to prepare them to get past the paper and glass screens, which means they cannot be 2D like the paper, and must be large enough to not fall with the broken glass. See our low-down on metal recycling!


Last but not least, plastics. Plastic is so cheap, so easy to use, so everywhere, and so… hard to recycle! Unlike metal and paper, which can often be recycled back into exactly what they were, most plastics can only be recycled into textiles, which then can only be recycled into things like rags, and maybe insulation or stuffing, which then struggle to be recycled. Writing this series has made me more aware of how everywhere plastic is and how hard it is to actually recycle. I think one of my upcoming series may be ways to avoid plastics altogether!

When it comes to recycling sorting, plastics are what is left behind when everything else is sorted. They are separated by type and from the trash by artificial intelligence and optical (light) sorting machines. Of surprise to me, plastics going into our blue bins must be “containers”. No Styrofoam, films, bags, hoses, those black pots for starter plants, etc. The one exception is #1, #2, and #5 plastic cups, which can be recycled – but note this does NOT include Solo cups. See our low-down on plastic recycling!

Recycling Takeaways

We hope you learned a few things in reading this! Here are a few final things to know.

Remember our map of recycling centers around town you can use as drop off centers for all those things that you can’t put in your blue cart. One in particular to highlight is Dane County Clean Sweep, which takes a lot of things that not only shouldn’t go in your recycling, but shouldn’t go in your trash either. Rechargeable batteries, electronics, paints, chemicals, cleaners, home demolition and construction debris – there is a long list on their website, and any Dane County resident can drop off there.

Textiles are very hard to recycle. Goodwill will take fabrics, but know that the best that can usually be done with them is downcycling to rags. Reducing consumption and selling/buying second hand is the best way to go here!

Check out this link for medication drop off.

Food is another big waste item. Reduce food waste by planning out meals in advance and going to the grocery store to get what you need for your plan when you are not hungry. Know what’s in your fridge and eat the left overs. Make new meals with old foods (soups are great for this!). Compost what you can.

And here’s my last graphic for you – a few extra and important things to remember from this post! Thanks for reading this pet project of mine!