Process reasoning
A hydrocyclone uses pressure-driven swirling flow without a rotating bowl. Its separation depends on feed pressure, geometry, density difference, particle characteristics and the water split between outlets. A decanter uses a rotating solid bowl and a scroll to remove settled solids. Its mechanical transport can produce a different solids discharge and operating burden. Neither choice should be made from a single nominal particle-size figure: actual efficiency changes across the particle-size distribution.
ILLUSTRATIVE EXAMPLE
Apply the reasoning
A mineral plant may need to remove a coarse fraction before a downstream clarification stage. A hydrocyclone classification trial can be appropriate for that split, while a decanter trial may address the remaining fine slurry or a dewatering target. Replacing the two-stage objective with one machine can change the product-size distribution and water balance. Specify whether the desired result is a size cut or the driest practical solids.
What to record
| Item | Basis to document |
|---|---|
| Driving mechanism | Hydrocyclone: feed-pressure energy; decanter: rotating bowl and scroll |
| Key trial output | Classification curve and water split / capture, clarity and cake condition |
| Important load | Pressure and hydraulic flow / hydraulic flow and dry-solids transport |
| Plant boundary | Feed pumping and recirculation / drive, conveyance and liquid return |
Review checklist
- State whether classification or dewatering is the primary objective.
- Record both outlet flow rates and particle-size distributions.
- Include pump power and recirculated water in the comparison.
- Evaluate wear with the actual abrasive solids.
Your next decision
Use a common feed and a common product-quality basis. If a hydrocyclone achieves the desired coarse separation simply, a centrifuge may belong downstream rather than replace it. If the real requirement is continuous solids recovery and reduced water in the discharge, request a decanter trial with explicit solids-transport and moisture targets.