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Aluminum swarf/chips processing

metalmadness

Hot Rolled
Joined
Nov 25, 2015
Hey everyone, hope you're doing well.

I am curious to see how other shops are managing aluminum shavings/swarf/chips. We machine a lot of different materials so we don't usually recycle. However for the past 3 months our machines have been processing A LOT of aluminum almost exclusively. So I have done some small batch recycling in the past but that was annoying.

My thought is to buy a 2 huge garbage cans...one I will drill a bunch of holes in, and the other will be used to collect any runoff coolant/water. I plan to "rinse" the chips with clean water initially and then let them drain. Sound like a good plan? The amount that we are processing will not be massive but it will certainly take several "batches" of this process to get it all through.

I know for bigger shops they sell these centrifuges which separate the coolant out...obviously we aren't going to be buying one of those.

Do they make small chip compactors to brick-ify the swarf?

What is your method?
 
20 gal perforated "Brute" garbage can goes in a 32 gal "Brute" garbage can (no washing, just get as much coolant off as possible). After shaking and waiting awhile, the sort-of-dry chips go in a row of 32 gal garbage cans that have sorbent socks in the bottoms.

Watch the weight! When you say "huge", think about who is going to lift them and move them around. If I'm not careful I can end up with well over 100# of Al chips in a 32-gal can. Doesn't sound like much, but try picking 8 of them up and dumping them into the recycler's bin that is 5' tall. Ouch time, at least for me.

Regards.

Mike
 
I find it's not really worth my time. I used to give them to my hillbilly neighbor to scrap out.
He'd take 2 garbage cans full and get $14. Apparently it was worth it to him.

Then he borrowed $50 off me and I haven't seen him since.
 
BTW, the only local shop I know of that briquettes their swarf does it to reclaim the straight cutting oil they use ... they throw away the briquettes.

Regards.

Mike
 
BTW, the only local shop I know of that briquettes their swarf does it to reclaim the straight cutting oil they use ... they throw away the briquettes.

Regards.

Mike

Hmmmm yes I figured it wouldn't be worth it/viable but I figured I'd ask. I do have the Brute style cans at the shop currently...since I will be doing most of the lifting I will probably want to limit it 75# or so.

To me it definitely is worth it as far as effort, I mean 100# of chips = $30 or so dollars around here....if I have 300+ pounds then that ain't nothing. I can buy myself a nice endmill as a reward lol. Or pizza. On top of all the 6061 and 7075 chunks that need to go recycle I would say its worth it, esp since we only do this once or twice per year. And I'd rather not just throw it away....aluminum is infinitely recyclable and very expensive to mine and alloy from scratch. And terrible for the environment.
 
Do they make small chip compactors to brick-ify the swarf?

What is your method?
Those compactors aren't cheap. And probably not cost effective unless you're a production house doing a shit ton of aluminum.

What we do is we have a big garbage can from Home Depot, and we put one of those Little Giant submersible pumps (with a 6 foot garden hose connected to it) at the bottom of an empty can. Then once it's filled with aluminum we then turn on the pump to drain out the excess coolant back into the tank then dump the chips into the big hopper out back.
 
I started rinsing my chips with the water I use to rinse my parts off a couple of years ago. I hardly add coolant concentrate anymore, it's made a huge difference.
 
We used 55gal drums for chip storage, in our area they were literally cheaper than decent garbage cans. The nice thing is they hold up really well to abuse, and you can use standard drum handling equipment to move them (fork attachments, hand trucks, lifting chains). If you get the ones with the removable tops they seal up nice and tight for outdoor storage.
 
Offer those chips on your local Craigslist. There are hobby guys that smelt aluminium and would love to have those chips.
 
BTW, the only local shop I know of that briquettes their swarf does it to reclaim the straight cutting oil they use ... they throw away the briquettes.

Regards.

Mike
That's pretty depressing.

I have a bunch of plastic tubs that sit behind the swarf chutes on my machines, when they're getting full I tip them into one of three ex-council wheelie bins I got for free.

When those are full I email a local scrap dealer, they send someone over, drag the bins onto the back of their flat bed and weigh them in for me, bring the bins back and pay me per kg, used to be £0.50 a kg, last 12 months that is £0.25 per kg for alu. Tbh if it was £0.00 per kg I'd still collect it and let them take it, someone can make a buck and the swarf can be reused.

The idea of just throwing away good stock for the recycling process is just sad and suggests there is something wrong somewhere.
 
That's pretty depressing. The idea of just throwing away good stock for the recycling process is just sad and suggests there is something wrong somewhere.

They throw them away because they are mixed Al, stainless, mild steel, whatever. No recycler will take mixed ... briquetted or not.

Regards.

Mike
 
Make a rectangular, ceramic mold. Wait for sunny day. Melt the chips into the mold with a large fresnel lens. Now you have aluminum stock for fixturing and jaws.
 
They throw them away because they are mixed Al, stainless, mild steel, whatever. No recycler will take mixed ... briquetted or not.

Regards.

Mike
Mixed I can understand, especially when the prices are currently pretty low but I've read plenty of posts on here in the past of people just binning even non-mixed swarf.

I'm lucky in some ways because I'm not a job shop so I generally try and group production based on material type to reduce how often I need to clean out machines to avoid mixed swarf, I just cleaned one lathe out after doing a sub job in acetal yesterday and that lathe will probably run alu for the next 12 months and nothing else.

Plastics are a whole different story, no one wants that stuff, not even the good stuff that can get recycled ends up being recycled half the time. I rinse acetal swarf with water to recover some of the coolant and leave it in tubs for as long as possible to drain, amazing how much sticks to it.
 
20 gal perforated "Brute" garbage can goes in a 32 gal "Brute" garbage can (no washing, just get as much coolant off as possible). After shaking and waiting awhile, the sort-of-dry chips go in a row of 32 gal garbage cans that have sorbent socks in the bottoms.
The spill containment devices for barrels work well for this. One of my lathes conveys coolant out with the chips. We put a barrel under the conveyor with holes in the bottom, and set that in a containment pan. We have a forklift tilt girdle around the barrel. When full, we lift the barrel out and dump it in a bigger bin, and dump the coolant out of the containment pan back into the machine. The bigger bin is parked at an angle so the remaining coolant drains to a hole in one corner and out into a bucket. By the time the chips in the bigger bins are ready to go to the yard, they are dry.
 








 
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