Recycling behind the scenes
Recycling behind the scenes
Kerbside mixed recycling is back up and running, and there have been a few random things coming in through the bins - among them dirty nappies, a vacuum cleaner and more than one pair of slippers (due to excessive lockdown wear?). What you put in your bin matters, not only because our recycling has to meet high quality standards, but also because there are real people sorting our recycling.
People often ask me about what goes on behind the scenes. So here’s what happens to your mixed recycling when it leaves the kerbside:
Scene 1, in the truck
The recycling truck arrives and picks up your mixed recycling bin. The driver can see the contents of the bin on a camera as it falls into the back of the truck. They will get out and sticker your bin if they spot the wrong things in your bin. But they can’t remove the contamination once it’s in the back of the truck, and too much contamination can ruin the whole load of recycling.
There are some especially problematic materials. Aerosol cans and lithium batteries should never be put in any bin (rubbish or recycling) because they can cause fires in the back of the truck. There’s no way you want a burning load of recycling dumped in your street, so it’s a good one to be super careful about.
Inside the truck is a big arm which moves the recycling around to make room for the next bin load. Things that can splatter e.g. nappies (sorry for the mental picture) and liquids or food inside containers can be punctured and smeared all over the load. The quality standards for cardboard and paper mean that wet materials can’t be recycled, so they can be ruined this way.
Scene 2, at the Wakatipu materials recovery facility
The mixed recycling load is tipped out into a massive shed. Inside is a series of conveyor belts and metal bins, something like a cross between Charlie and the Chocolate Factory and Chicken Run. The recycling is shunted up and down, blown with compressed air, dropped through holes until it’s separated into the different materials. But machinery alone can’t do the job, especially when the sorting machinery is old like ours is. Workers with ear-muffs (it’s noisy), fluro jackets (it’s cold) and eye-protection stand at various points - helping to pull out the right materials to be recycled.
The recycling crews work hard. Smelly, dirty things make their job a lot less pleasant. Nappies and food waste are the nastiest things to deal with. Needles are the biggest fear, but luckily not too many of those come through. Glass (which is collected for recycling in a different recycling bin and goes to a different bunker) is sharp, and can contaminate all the cardboard when it gets broken. Food is smelly and obviously can’t be recycled. Keeping all these items out of your mixed recycling bin will not only look after your recycling, but also the recycling workers who do the job for all of us.
Soft plastics are the most common mistake people make. Soft plastics can’t be recycled in our district. If you can squash it in your hand (like plastic bags, glad wrap or chip bags), it goes in the rubbish bin. Dirty food containers are a big problem. They smell, and don’t meet the quality standards. If you want your take-away containers (eg curry) or plastic jars (eg mayo) to be recycled, the food has to be removed before you put them out for recycling.
When it comes to plastics, only the kind of plastics that you buy in the supermarket can be recycled. We’re talking plastic food packaging, cleaning and beauty product packaging - these are the plastics bottles (1-7) and plastic containers (1-7) which can go in your mixed recycling bin. All other plastics have to go in the rubbish - toys, balls, plant pots, washing baskets, buckets, garden hose. Take-away cups - rubbish. Drink and food cartons or foil pouches - rubbish. It’s a lot of waste going to landfill, and yes, it’s a bit depressing, but that’s the reality. Sending all those non-recyclable materials off in your kerbside bin only makes it more difficult to recycle the things that can be recycled.
At the end of the sorting process, each material is baled and sent away to a reprocessor to be made back into a raw material. The bales should only contain clean, dry recycling of the same material. The sorting process can extract some contamination, but too much contamination in too many kerbside bins overwhelms the process and means quality standards can’t be reached.
So if you ever wonder whether what you put in your kerbside bin makes a difference, the answer is YES. Recycling only works when we all take care of it. For a full list of what goes in your recycling bins, go to:
What goes in the yellow bin:
- Plastic bottles 1-7 (eg soft drink, juice and milk bottles)
- Plastic containers 1-7 (eg yoghurt and ice cream tubs)
- Cardboard (dry with no oil or food-scraps)
- Clean paper