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Is it possible to "pump" a powder the same way liquids can be pumped?

If so, what are the challenges? If not, what are some alternatives?

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    $\begingroup$ This is a common problem in industrial processes. In fact, there's a trade publication, Powder & Bulk Solids, devoted to it. $\endgroup$ – Dave Tweed Jan 21 '15 at 18:01
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    $\begingroup$ Are you looking for the ability to run the solid materials through a pump or just the ability to transport the material through an enclosed pipe? Can you help define the problem so answers are a little more helpful to you. $\endgroup$ – Dopeybob435 Jan 23 '15 at 14:19
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I believe it's termed "injecting" not "pumping" but yes, it's certainly possible.

Coal fired electric power plants grind the coal to a very fine dust and then blow the dust into the central burner.

This particular article is a summary of some DOE research for a Blast Furnace Granulated Coal Injection System Demonstration Project.

And this article discusses some of the hazards from a National Fire Protection Association perspective. Coal dust having the particular dangerous property of being explosive and all that...

As far as specifics regarding danger, I suspect it will vary depending upon the material(s) involved in the powder.

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  • $\begingroup$ They can do this so simply as if it were a liquid? $\endgroup$ – peterh says reinstate Monica Jan 20 '15 at 18:44
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    $\begingroup$ @PeterHorvath - define "simply." :-) An incompressible material can be treated as a fluid in many cases. Depending upon the powder and form, it may be treatable as a fluid and therefore be able to be pumped. $\endgroup$ – user16 Jan 20 '15 at 18:47
  • $\begingroup$ I am thinking on pipes and pistons. My intuition says with powder could it be probably stick. Very fine powder has very small, but solid particles capable to drag on eachother, liquids doesn't. $\endgroup$ – peterh says reinstate Monica Jan 20 '15 at 18:50
  • $\begingroup$ liquids experience similar effects of drag as what you're contemplating. Flow rate & material type determine whether the flow is laminar or turbulent. Regardless, a properly configured system can pump / inject a powder. $\endgroup$ – user16 Jan 20 '15 at 18:53
  • $\begingroup$ @PeterHorvath I think Fluidization is the main process, here. In your comment about stickage, you are starting to make assumptions about particle types, conveyor temps and properties, the environment (pistons), etc, which would have been invaluable aspects to ask in the question. $\endgroup$ – New Alexandria Jan 21 '15 at 0:43
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While pumping powders as a mix with swiftly moving gas is viable, one of frequently used alternatives for both powders and granular materials is Archimedes' Screw.

enter image description here

Essentially, a helix in a diagonal pipe making the material "pour/roll" upwards the curve, allowing lifting it a long distance. This solution is frequently used in farming equipment for transporting grain or granulates. While it doesn't provide "pressure" for moving it through inert pipes, a "pipeline" of such screws can go a long way, and while it restricts transport angle, it provides a viable alternative especially for heavier materials where extreme air flows would be required to move them.

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  • $\begingroup$ Archimedes' screw isn't the most commonly used term however- I'd recommend searching for "screw conveyor" instead. $\endgroup$ – ericksonla Aug 30 '18 at 20:23
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You may also look into pneumatic conveying. It involves fluidization of the particles.

This simply uses pressure differential to move any bulk material. It's used a lot in industrial applications. You can read a summary of those systems, here.

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    $\begingroup$ Could you give a small overview of how and why pneumatic conveying works? I'm sure it would make the answer even more useful. $\endgroup$ – Trilarion Feb 3 '15 at 16:34
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There is a key difference between liquids and powders:

  • Liquids have internal cohesion and can be sucked, but with a powder, you need a carrying medium.
  • The internal friction in a powder will usually be far higher than in a liquid.

In practice, this means that to pump a powder, you inject air or another gas as fluidizing agent. The pumped or blown air carries the powder, like a dust-storm within the pipe.

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In food process you can "pump" powder with vacuum, sugar works very well, and some other products need sometimes some technical adjustment (pression or open/close cycles valves) . But water in the pipes is ban and last point it's only for small quantities and short distance 20meters max i think.

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You can pump both liquids and powders into a "mold" using injection molding.

It works more easily with liquids, but it can also be done with small particles such as powders that are injected into heated molds with sufficient force.

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  • $\begingroup$ Does this really pump a powder. What force/effect is used to actually pump the powder? $\endgroup$ – Trilarion Feb 3 '15 at 16:33
  • $\begingroup$ Can you provide a link to a an application where particulate matter is conveyed using injection molding? I have a little experience with injection molding, and I've never heard of anything outside of polymers being used. $\endgroup$ – NauticalMile Feb 3 '15 at 21:01
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We have dry cement bulkers truck running on local roads, feeding dry cement to mixer factory where it is turned into wet mixed cement. Pump air into the truck to 'blow' cement out.

This video shows cement and sand are 'blow' by air. Powder (cement/sand) are placed in closed container. Air blow in and powder come out on, says, 2 to 3 inch diameter, tubing. Powder can be transferred in construction site, at horizontal and vertical distance of tens of meters. You can see the blue air-compressor in the video. Here is a similar video.

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  • $\begingroup$ Well, the first question of the site is like a lighthouse. :-) Anyways, I would suggest to add to your last sentence some details, I don't understand what exactly happens and how. $\endgroup$ – peterh says reinstate Monica Jun 28 '16 at 8:47
  • $\begingroup$ youtube.com/watch?v=tCdOvP3j1t4 $\endgroup$ – EEd Jun 28 '16 at 8:56
  • $\begingroup$ Insert the link in the answer, and also add verbal explanation, what is there. For example, currently I don't have access to youtube, or the video will be in the future maybe removed, this is why it is a requirement. $\endgroup$ – peterh says reinstate Monica Jun 28 '16 at 9:05
  • $\begingroup$ This video shows cement and sand are 'blow' by air. Powder (cement/sand) are placed in closed container. Air blow in and powder come out on, says, 2 to 3 inch diameter, tubing. Powder can be transferred in construction site, at horizontal and vertical distance of tens of meters. You can see the blue air-compressor in the video. youtube.com/watch?v=tCdOvP3j1t4 Similar, youtube.com/watch?v=p74BAe-OYq0 $\endgroup$ – EEd Jun 28 '16 at 9:10
  • $\begingroup$ This is what I've thought on. $\endgroup$ – peterh says reinstate Monica Jun 28 '16 at 9:13
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Yes you can pump powders using a diaphragm pump. The above comments all focus on alternate ways to transport powder they are not talking about pumping. Check out powder pumping with a diaphragm pump on youtube.

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