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Testing - Particle Attrition    
Services > Testing > Bench-Scale > Particle Attrition
   

ATTRITION OF BULK SOLIDS, MATERIAL DEGRADATION

Friable solids can readily experience particle attrition (i.e., breakage, size reduction, or fragmentation) during routine handling in many bulk material operations. Particle attrition can be caused by variety of mechanisms like compression, impact, and shear. The effects of material degradation can be costly, such as increased dusting, caking, poor product performance, or safety issues.

Typical factors affecting particle attrition include:

 
  • Particle hardness
  • Particle shape and size
  • Energy of particle impact
  •  
  • Surface impact vs. particle bed impact
  • Surface hardness
  • Particle chemistry or propensity to melt
  • Particle attrition tests can be performed where we set up a physical model to investigating the effects of major variables. We measure the particle size distribution pre- and post-testing or provide samples to your laboratory for any proprietary analysis you perform. Key material degradation studies follow.

      Particle attrition tests   Applications
     
  • Impact mechanism
  •  
    • Evaluate attrition during filling of silos,
      hoppers, transfer chutes
     
  • Hopper flow mechanism
  •  
    • Evaluate attrition due to funnel or mass flow
      discharge from a hopper
     
  • Pneumatic mechanism
  •  

    Solutions for reducing or eliminating particle attrition problems include:

     
  • Modify process – reduce particle velocity or impact pressure
  • Modify the bulk solid – change particle hardness, shape, or size
  • Modify the equipment – use shock-absorbing surfaces or special elbows
  •  

     
    Particle attrition during conveyingParticle attrition during conveyingExample results from particle attrition testsExample results from particle attrition tests
    (click to enlarge)
    Samples from coffee bean particle attrition testsSamples from coffee bean particle attrition tests