Particle Properties

Why Particle Properties Testing?

An understanding of particle properties is just as important as knowing bulk material flow properties.  Particle properties such as size, shape, porosity, and true density can affect powder flowability, reactivity, caking, attrition/friability, absorption/adsorption, segregation behavior, and most importantly process or product performance.

Particle Properties Tests

Particle properties can be performed to evaluate characteristics such as size/shape, interaction with moisture (as a liquid or vapor), or strength/durability.

Tests focused on particle size/shape

  • Particle size distribution:  via sieve analysis or laser light scattering technique
  • Particle density:  “true” solid density of particle; not the same as bulk density
  • Microscopy:  magnified images of particles focusing on shape
  • Dustiness:  measurement of dust release as function of gas ejection velocity

Tests focused on particle/material and moisture interactions

  • Saturation moisture content:  maximum moisture material can retain without becoming a slurry; needed for wet material handling or stockpile design
  • Moisture sorption/desorption:  powder’s tendency to gain or lose moisture at a constant temperature; important to understand caking behavior
  • Dust extinction moisture (DEM):  moisture at which material (-1/4 in./- 6 mm) does not emit dust; used in stockpile dust emission projects
  • Transportable moisture limit (TML):  evaluation of material liquefaction behavior for maritime cargo; critical for meeting maritime codes

Tests focused on particle strength/durability

  • Crush strength:  particle breakage force (as function of time); required to understand breakage strength of pellets, agglomerates, or finished goods
  • Drop shatter:  measurement of freeze conditioning agent’s effectiveness on preventing coal caking; critical for coal bunker design for freezing conditions
  • Unconfined compressive strength:  rock breakage strength required for crusher or other communition equipment selection

If you do not see a particle test that is required for your project, contact us.  We can have other particle properties tests run such as mercury or nitrogen gas porosimitry (for estimation of particle surface area/porosity), scanning electron microscope (SEM) imaging, and dilatometry (particle sintering behavior at controlled temperature and humidity).

Test Results

The particle properties test results will be issued in a report containing:

  • presentation of the data
  • description of the test apparatus or procedure
  • summary of observations and conclusions

A Jenike & Johanson engineer will also review the particle properties test results with you and answer questions you may have about the test conclusions and their application.

Need to send samples for testing?  Click here for additional information.

What's Next

Contact us to review your specific particle properties testing needs with one of our knowledgeable engineers.  We also recommend you review our typical project approach to see how we can utilize your particle properties to improve your product quality, production efficiency, or safety of your operation.