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Plastic Mill

This topic contains 19 replies, has 5 voices, and was last updated by  Donald Hugens 1 month ago.

1
Jorge Cerezo jorgecerezo

Plastic Mill

18/06/2019 at 00:13

Hey there, i´m not sure if you guys had that idea before but i will tell anyway.
What if you guys build a huge plastic mill as big as posible that at the same time is used as a shreder to grind plastic on industrial scale, powered by wind. (the historical mil that is used to grind grain). I don´t know if i had expresed myself correctly, please forgive my bad english. Have a nice day.

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In reply to: Plastic Mill

warrior
18/06/2019 at 06:27
2

Building a mill might be a bit over the top, but repurposing one?
Why not.
Would be an interesting ‘hack’!

In reply to: Plastic Mill

starter
18/06/2019 at 14:07
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I think that it would create huge amount of dust particles which is not good at all. Alsothe plastic are not brittle so it´s hard to crush them they would be melting under the shear, but that is just my opinion, maybe I´m wrong.

In reply to: Plastic Mill

starter
18/06/2019 at 14:25
1

Yeah, maybe that is a better proyect to start with and also saving many resources that are needed. Otherwise am not an engineer so i´m only thinking about it.

In reply to: Plastic Mill

starter
18/06/2019 at 14:32
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I think you are probably right. But I also think that a good engineer could design a mill that cut the plastic into small pieces instead of crush it, and also solving other problemas that you also comment. The idea is to build a bigger shreder which process more amount of plastic, and also is powered by wind so is more ecological.

In reply to: Plastic Mill

dedicated
18/06/2019 at 15:01
1

i’ve been investigating shutdown/abandoned water and wind mills here in Catalonia and the rest of Spain; there is definitely room for ideas and success; unlikely to be implementable at scale under the strict regulations but eventually there could be some take away for the developing world. Strong rivers provide quite some power but also the logistic means to build a recycling (more precisely shredding) network on it. Unfortunately we lost funding to develop this idea further. Anyways, if anyone could start completing the math for a water mill, eventually somebody could develop a crusher for it. My last calculations did end up with a 2.5 meter diameter wheel which provides enough torque for a larger shredder; only applicable with a stronger river at 1-2 m per secs.

In reply to: Plastic Mill

warrior
18/06/2019 at 15:56
1

@pe-trhlinka

True if you use them ‘as is’ (grinding the plastic) but using them as just as a ‘KW motor’ to drive a shredder, I think it would result in an EPIC!

 

In reply to: Plastic Mill

warrior
18/06/2019 at 16:01
2

@pex12

First part of:


Didn’t anybody ever mention using a vortex on the platform?

(you know where I live 😉 )

In reply to: Plastic Mill

warrior
18/06/2019 at 22:05
2

There is a considerable vortex element in both the Francis turbine and the vertical Kaplan turbine.  I’ve also seen very old, small, low-head, vortex enhanced, vertical water turbines in Crete – that would have had a tiny power output (maybe under 200 watts), but was just enough to drive a small corn mill or olive press. They fell out of use when small engines and cheap electricity became available. But it is good that people keep reinventing them.

In the valley where I live, people have looked into restoring some of the old derelict woolen mill water courses – to install generators – but the cost is currently too high for the amount of power available.  That will probably still be the case unless the cost of fossil fuels shoots up to enormously high levels.
There are, however, one or two very small domestic scale water turbines operating in the valley.

There are also a number of small (farm scale) wind powered generators in the area – one of which is partly financed by a community cooperative – but it is very difficult to get planning permission to build any new ones at the moment.

If direct mechanical drive was used to power small plastic processing machines, then the relatively large losses involved in generating electricity and driving motors could be avoided – which might mean a relatively small scale wind turbine could be used. But the cost of building it would probably still be lost, as there is still nothing in the way of a decent pay-back from small scale waste plastic processing.

In reply to: Plastic Mill

dedicated
18/06/2019 at 22:23
1

yeah, i dont think producing electricity to run a shredder as the op intended is really needed. the torque at the shaft of a 2-3 meter water wheel should be more than fine. same goes for wind powered devices. would be awesome to work out such thing for those who really need it, Africa, Asia, etc… Lots coast lines down there have seasonal rivers/water falls, so strong its just spectacular thing to see (having occasional visits myself). More or less this could be build for below 10K. Extra challenge might be to wash and shred the plastic in one go though.

In reply to: Plastic Mill

warrior
18/06/2019 at 22:42
2

More details of the vortex turbine shown above:

In reply to: Plastic Mill

dedicated
18/06/2019 at 22:57
1

yeah, i really like the device but seriously, this product is insane expensive, 80-300K. for this price you could build at least 2 or 3 complete water wheel powered shredders. developing one from scratch should be possible though; there are enough second hand generators; machining the propeller isn’t that difficult 🙂

In reply to: Plastic Mill

starter
19/06/2019 at 00:39
1

@pex12
I think that build a shredder powered by wind/wáter is far more easy than the current eolic Parks, (dont know if that is how it is called). The size of the mill wouldnt be as the old ones, or this new ones, just enought to be able to cut the plastic on the way that your current shredder does, and if that Works, later on should be good testing bigger sizes.

In reply to: Plastic Mill

starter
19/06/2019 at 00:53
1

@frogfall
The investment of the Project is quite a problem because it wouldnt be cheap by far, but if we did the maths, maybe in 15 years it would be all paid, i dont know.
It is hard to tell when there is so Little material to discuss about but is fun.
I think that the problem of the pay-back you also mentioned probably could be solved by the mill, because it would proccess more plastic on industrial ways, and also wouldnt have the cost of electricity.
Everything has to be calculated so i dare someone have a try. Have a nice day.

In reply to: Plastic Mill

warrior
19/06/2019 at 08:28
1

The point of showing the turbine is not to request a quote, but to show the tech.
Good to know the maximum price for a turbine, but off the grid DIY installs are only a fraction of the costs, in almost all cases.

If a Vortex can generate 15kW of power, it should have more than enough energy to direct power a shredder (so NOT using electricity) even if the transfer of momentum would be ineffecient.
So the real question in the Topic should be: how can you efficiently transfer ‘rotary power’ of any source (or size) to (off the grid) power (the) machines (leaving heating out of it (for now))?

It’s probably a matter of finding/building the right Gear box (or belt system).

I can Imagine that to a machine builder this is a ‘no brainer’, but is there a way to give all of us ‘the power of gear’?
A V-zero machine, existing scaleable tech as the missing link between rotary motion (be it a bike or a turbine) and the rotary motions of the machines.

The archives are probably also full of waterpowerd ‘saw mill’ examples (@frogfall 😉 )

This actually is a FAQuestion, it keeps popping up in many ways, shapes and forms. Why not answer it it with a belt driven machine extension?

To build yourself or sell in the Bazar (at a comparable price of a motor install? (@pex12))

In reply to: Plastic Mill

dedicated
19/06/2019 at 09:52
2

yeah; the installation of this vortex thing is going to be nasty and insane expensive in the western world 😉 I have my doubts it’s creating up to 100Kw but ok. I’d prefer a mobile unit …
No worry about the transmission via belts, it’s done since 150 years in steam powered machine shops (one to drive them all). typically you use multiple belts and it’s quite good; most lathes til the 1990s do that.

and yes, i think we should compile a few more but complete pages about shredder drive types; i have enough details for sprocket-chain drive, 3 phase, single phase, solar and the missing part is wind or water powered which is more interesting to help our buddies down in asia, africa (the more serious and urgent audience)

our partners complete this weeks a municipal shredder, 7 tonnes, 90Kw, shreds everything, via chains (no idea yet how this works); assembly is in 3 weeks; will let you know.

Attachments:

In reply to: Plastic Mill

warrior
19/06/2019 at 23:26
1

The vortex turbine seems to be doing a good job at extracting power from such a low head (15 kW from a drop of only 1.5M) – but it does require a rather high flow rate (1800 litres per second).  If you look at this chart of “compact” turbines from the long established Gilkes company, then you can see that the flow rate is enormous, and the head is tiny, compared to most “low power” installations.
Historically, these would be the sort of heads and flow rates used by undershot water wheels.  (I’ll have to do a bit more digging through my reference books to see how the efficiency of the vortex device compares). n.b. The total potential power, of the head & flow rate listed, is 30kW – so if the vortex device is actually generating 15kW then the efficency is 50%

As for wind powered saw mills, @donald, I’m in no position to describe them to a Dutchman 😉

In reply to: Plastic Mill

warrior
20/06/2019 at 09:05
1

@frogfall
I would think a vortex is just a way to lengthten the drop so it can more effectively harvest the ‘speed’ of the water instead of just the ‘drop’, transfering power to the entire ‘wheel’ instead of just the quart of a normal water wheel.
If I had to guess, I would say a single vortex is 3-4 times more effective than a wheel.
I’d love to hear the actual numbers.

And cool video. I was only missing the tullips 🙂
You would indeed need to keep variable speeds into account, at least with wind.
Don’t know if a shredder could handle this, as it of course also depends on it’s momentum and not just ‘brute force’ (otherwise they would not jam that often).
On the other hand, wind would have no problem driving a brute force shredder, if it were so designed.
Interesting.
Still also rooting for my blender concept though!
(vortex: shred, wash and sort).

In reply to: Plastic Mill

dedicated
20/06/2019 at 11:50
2

@donald, having no idea about specifics I’d say the vortex incl. installation exceeds easily the 15K when done DIY and without any checks/certification, assuming you have a complete full park of good machines, incl. a 5-6 axis CNC; shredder or extras not incl. the complete wheel variant is just a tiny fraction and would be mobile; just saying 😉

In reply to: Plastic Mill

warrior
20/06/2019 at 12:03
1

@pex12
>the complete wheel variant is just a tiny fraction and would be mobile
mmm, mobile, who would have thought, lol 😉

True, wheels are way easier to build, but would also require way more space. It’s a trade-off.
And 15K ain’t that much for 15kW, it’s comparable with the costs of Solar (at least where I live). Or actually it would be cheaper, as, well, the water won’t stop flowing at night!

Still gonna need a stream though…

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