Grinding & Classification Circuits

Grinding & Classification Circuits 2017-04-04T06:57:16+00:00
  • To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Grinding.
  • OR Select a Topic that Interests you.
  • Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
    Using Add Reply allows you to Attach Images or PDF files and provide a more complete input.
  • Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.

Hydrocyclone Selection Criteria (9 replies and 1 comment)

12 months ago
spaceexplorer 12 months ago

I need help in selecting the ideal hydrocyclone(s) for our intended application. Any suggestion would be greatly appreciated.

The contemplated project involves the reconcentration of old tailing piles, using centrifugal concentrator, such as the ICON-i350 concentrator, to recover the fine gold contents.

The project will be located in a desert area in Mexico, where scarcity of water is a major factor.

For the project to be feasible, clean water must be recovered from the process effluent slurry (consisting water, fine sand and silt); and recycled back in the process on a continuous basis.

That is where the hydrocyclone comes in.

The idea is to channel the discharged slurry, containing 20% - 30% TSS of sand/silt, through in-line hydrocyclone(s) at approx. 450 GPM; for the purpose of removing the solids, on continuous basis.

What type and size of hydrocyclone(s); and at what operating pressure (psi), would be ideal to obtain the desired results? Any useful suggestion would be greatly appreciated.

Thank you for the time and attention.

12 months ago
dk 12 months ago

If there is scarcity, you may recover maximum process water in cyclone-paste thickener  system. You may also undertake studies on alternate dry processing to avoid using of process water to the minimum.

Sugar Watkins
12 months ago
Sugar Watkins 12 months ago
12 months ago
jpearcy 12 months ago
2 likes by Sugar Watkins and David

You may also check on the following Link (just an example of hydrocyclone manufacturer brochure):

There is a chart that will help you. It looks as if one D15 hydrocyclone could handle your flowrate at 10 to 20 psi pressure drop, in case you allow particles of less than 50 - 110 microns to be present in the clear water, or else, you should go for a cluster of D6 hydrocyclones (5 or 6 of them) if your overflow cut point for particle size is 35 - 75 microns.

12 months ago

Hi JPearcy.
Thanks for your comments and suggestions. I have already started looking into the Krebs D15 hydrocyclone and a possible cluster od D6 hydrocyclone. I will keep you posted on my findings.
Your comments and suggestions are greatly appreciated.
I found this forum very useful, with the participation of highly knowledgeable professional. I commend you, David, for making this possible.

12 months ago
richardh 12 months ago
2 likes by Makgetsi and David

The use of hydrocyclones in such an application will require the use of cluster of multiple small sized cyclones to try cut as fine as possible. However the issue is if there is very fine material and clay present in the water, a hydrocyclone cluster may not be able to clean it sufficiently. The rule of thumb is the smaller the cyclone diameter, the finer the cut point. The other issue is the finer the material, the wetter the cyclone underflow product will be as it is a function of particle surface area. The finer the material, the more the surface area and the "wetter" the cyclone underflow, before roping occurs and the cyclone loses efficiency.

If you have a PSD available I can look at sizing a unit for this application.

I hope this helps.

12 months ago
spaceexplorer 12 months ago

Thank you Richardh for your comments. Attached hereto is a rough Process Flow Sheet of the tailings beneficiation project, to help illustrate our needs and the desired results.

I look forward to your feedback. Please accept my gratitude.
Bill Fraser
12 months ago
Bill Fraser 12 months ago

Do you have a Particle Size Distribution of what you want to feed that cyclone?

12 months ago
richardh 12 months ago

Bill, I agree as that would be one of the determining factors.


12 months ago
spaceexplorer 12 months ago

Much thanks to Bill Fraser and Richardh. The particle size fed to the cyclone(s) will be max. -3.50 mm. Representing: -2.0 mm fed through the ICON-i350 Concentrator; and -3.50 mm fed through the Oro Low-G Concentrator.

Your comments and suggestions are greatly appreciated. Thank you for your time and kind attention.

12 months ago
richardh 12 months ago

For the flow of 450 US GPM (102m3/h) you could get away with one 10 inch (250mm) unit based upon the Multotec charts. This would cut at about a D50c of around 30um using a particle SG of around 2.7. running at about 110 kPa. My worry is the finer material which may be present in the overflow and the affect it will have the concentrators if it builds up. Will the treatment plant run on continuous operations or say day shift only?

A further point on the cyclone to consider is the top size it can treat without blocking. The rule of thumb for the above 10 inch unit is approx. 16mm particles.

I note the overflow you have filtered. not sure what filter you had in mind. I would fit an air-break between the cyclone and the filter, the overflow otherwise this could cause back pressure and affect the cyclone performance.

If the material has lots of silt and clay and thus fine particles you would need multiple smaller cyclones. The cyclone diameters getting smaller the finer the cut-point required and the number of cyclones increasing.

Please join and login to participate and leave a comment.

BUY Laboratory & Small Plant Process Equipment

We have all the laboratory and plant equipment you need to test or build/operate your plant.

ENTER our Mining Equipment' Store

We Sell EQUIPMENT for all types of Mineral Treatment PROCESSES and Laboratory Testing needs

Have a Mineral Processing QUESTION?

Come in, ask your question

911Metallurgist Community Forums

Talk to other metallurgists and be helped.


We can IMPROVE ALL PLANTS / Mineral Processing Engineering & LABORATORY Ore Testing

911Metallurgy Engineering

Contact us for process engineering, metallurgical investigations, plant optimization, plant troubleshooting, needs. WE “FIX” METALLURGY.