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Solid pump for plastic grinding.

Solid pump for plastic grinding.

Solid pump for plastic grinding.

(OP)
I want to continuously transfer plastic grinding of size approx 5 mm into the base of a water collumn about 10 feet height and dia 5 feet continuously.I would be grateful if someone could guide me as to how this be accomplished.

RE: Solid pump for plastic grinding.

We can probably guide you if we had a lot more information,such as the process from start to finish.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

(OP)
Thank you for replying.The material is grinding of polypropylenpe which floats on water.The material would be injected at the bottom and cleaned of contaminants while it rises and would be taken out in the overflow from the top.I haven't done this before but was trying to work out how this could be done and what equipment would be required.

RE: Solid pump for plastic grinding.

I have no solution.
Could you do it pneumaticly?
You might do better in materials handling or like forum.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

There are numerous ways to do what you ask but the pump is a very small piece of the overall process where all the pieces have to fit together. This is what process engineers do.

RE: Solid pump for plastic grinding.

(OP)
Artisi, Pneumatic injection might be a way but easier said than done.AThe pressure at the bottom will be quite a bit.Are there any pumps which can handle solids?I would appreciate any links to their details.WCompositepro, is there any link which might give some idea about how its done.

RE: Solid pump for plastic grinding.

Plastic bits of <5mm should pass through a common centrifugal pump of relatively modest size without clogging or other difficulty. I'd mock up the system with a ~1HP sprinkler pump or pool pump, run it for a while, then separate the pump, and buy a bigger one if the impeller has retained any plastic.


Even better, don't take the word of a random idiot on the Internet; talk to a pump manufacturer, supply them some samples of your plastic bits, and ask them to recommend a closed impeller large enough to pass your stuff, or an open impeller, a paper stock impeller, or even a trash pump impeller. Pumping bits of plastic in water is not new technology.




Mike Halloran
Pembroke Pines, FL, USA

RE: Solid pump for plastic grinding.

(OP)
Thank you Mike.

RE: Solid pump for plastic grinding.

Pumping doesn't sound like much of an option to me. These particles float so will always be on the top of any feed hopper feeding the pump.
Question: how do you ensure the plastic floating on top ends up in the pump inlet?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

Easy. Stabilize the water level in the feed tank, or float the pump inlet, facing up, a few mm below the water surface. The resulting vortex at the center of the inlet will pull in a little air, but it will also cause the particles at the water surface to flow radially into the inlet, and any particles above that to fall into the vortex.

Mike Halloran
Pembroke Pines, FL, USA

RE: Solid pump for plastic grinding.

(OP)
Artisi,a sort of slurry could be made having more plastic and less water.This would go into the hopper and hopefully be carried with the water.

RE: Solid pump for plastic grinding.

Having more plastic and less water could become a problem for pumping, you need to experiment with consistency to arrive a pumpable slurry and you have the problem of maintaining that consistency as the plastic will continually try rise to the surface.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

Mike:
Your suggestion has merit, the problem will be finding the best submergence so as to entrain the plastic while not entraining excessive air putting the pump off prime.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

This might be your solution.
https://www.bing.com/videos/search?q=how+to+pump+m...

this unit might be available with electric drive or capable of being modified.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

(OP)
Yes Artisi,
A floating pump with one of the impellers which Mike suggested should work.Thanks a ton.

RE: Solid pump for plastic grinding.

Some type of rotating screen with water sprays may be a more appropriate method to accomplish what you desire.

RE: Solid pump for plastic grinding.

In any process design you have to define exactly what you are starting with and exactly what what you want to end with.
What is the output of your grinder? Is it already in water? Dry?

A water ejector pump might work for you:
https://www.google.com/search?q=water+ejector+pump...

RE: Solid pump for plastic grinding.

(OP)
Bimr,conventionally it's done in a horizontal tank and rotating screens are used to get rid if dirt at initial stages.I was trying to see if it could be done more efficiently in some non conventional way.Compositpro, the required input is dry plastic grinding of bulk density approx 0.5kg per litre to be fed in and taken out at about 500 kg per hour.Can the water ejector pump handle solids?Ere you suggesting using this to feed into the base of the tank under high pressure?or are you suggesting this as a method of simply pumping solid plastic particles?

RE: Solid pump for plastic grinding.

(OP)
i have come acrooss something called a peristaltic pump.Any idea whether these could pump plastic slurry?In fact I just started another thread on these.

RE: Solid pump for plastic grinding.

Yes, they can-the problem is still handling the water / plastic mix into the pump inlet, the problem is not what pump type you use- but the feed problem.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Solid pump for plastic grinding.

Other options:

- feed plastic to tank bottom with long auger
- feed plastic to tank top, and mix

Or have a small tank with a mixer, you submerge the plastic bits by mixing and pump from there.


RE: Solid pump for plastic grinding.

Like MartinLe says, you're better off looking at either agricultural feed machines like this http://falconindustries.com/industries/agriculture or gravel loading and mixing systems. They make long ones for lifting grain into the top of silos so this sounds like that but in reverse.

Some sort of paddle mixer or agitator would seem to be a good idea

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