We can think of this column as “How To Louse Up the Sorting Machines,” and is a very big problem for the recyclers with whom I get to chat. The solution to the problem is easy enough, but requires all of us thinking about it whenever we are deciding whether an item is recyclable or not.
Sorting, of course, is required in order to sell recyclable materials. Cardboard is very valuable, but a bale of it cannot contain any plastic contamination. Number 1 plastic (soda bottles) is also very valuable, but cannot contain paper, aluminum or other types of plastic in its bales.
That means the sorting machines need clearly identifiable kinds of products in order to sort them into their respective piles. Those machines work by sorting things in specific orders, and by using a variety of ways to identify different products. Those can sometimes include light, weight, magnets, and air to separate different products from other stuff in the stream.
Cardboard is heavy, and is pulled out first with a roller system that lets other stuff fall through and floats the cardboard along on top of a conveyor to the baling machine. Another neat machine identifies a Number 1 plastic bottle with light, then shoots it away with a puff of air.
Air is also used to separate paper from the stream, and that is where much of the sorting problems begin. A small, light piece of plastic, like a coffee cup lid, for example, will float away with sheets of office paper and become contamination in the paper bale. Small items will also simply fall through the equipment and not sort at all, or essentially blow out of the machine altogether, and fall through as trash. Loose plastic caps or paper that has been torn into small pieces before being recycled fit this category. It’s why small caps can’t be loosely recycled, and why we should not tear up paper for recycling. It’s also why shredded paper is a problem, and is better composted than recycled.
Aluminum sheets, like the covers on yogurt containers, are recyclable, as are sheets of aluminum foil, but both can blow away with the paper scraps unless they are crumpled together a bit, so they are “seen” by the sorters as a lump, instead of a sheet.
The other big problem is stuff that gets tangled up in the machinery. Wire coat hangers, for instance, are steel, but they get wrapped around the moving parts of the sorting machines, which requires that the entire operation be halted for several hours so workers can safely climb in there and remove the debris. Any kind of wire, rope, hoses, or other long, stringy items will cause the same problem, whether the material from which they were made is itself recyclable or not.
Wood of any kind cannot be sorted into a recyclable commodity and is never acceptable in the recycling stream, nor are items that contain a mix of materials like steel and plastic, materials that are considered “final use” products within the industry, or things that are simply too big and awkward for the sorting machines to handle. Those include the stuff from the shed — rakes, lawn ornaments, outdoor plastic decking, outdoor furniture, old tools, etc. It’s a good general rule to consider that things from the kitchen are usually recyclable, things from the cellar or shed are not.
The Recycle Bin is a weekly column on what to recycle, what not to recycle, and why, in Brunswick. The public is encouraged to submit questions by email to brunsrecycleinfo@gmail.com. Harry Hopcroft is a member of the Brunswick Recycling and Sustainability Committee, though his opinions are his own and do not necessarily reflect those of the committee.
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