Analysis of powder and dispersion. Development of formulations and pigment testing
Flowability of powder
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Causes for distinctions in the flowability of powders
Causes for distinctions while handling powders and bulk solids are often different flow properties. We measure the flow properties of your bulk solids and powders.
Strongly cohesive bulk solids and powders can show differences in handling, transport, conveying, dosage and storage behavior.
This macroscopic powder behavior is dependent on factors such as humidity, particle shape, characteristic of particle surface, particle size distribution, cohesivity and caking behavior.
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Our aim is to characterize all these parameters and work with test methods which can distributing between the individual application cases.
testing methods
Cohesion test
The auto-adhesive properties of particles and their behavior in agglomeration can be described as their cohesion properties.
measured parameters
• Cohesion Index
Fig. 1: Evaluation of collected cohesion measurement data
baking test
Caking properties of consolidated powder is measured by Caking Test.
Measured parameter
• Ratio of coulumn and cake hight.
• Energy which is necessary to destroy consolidated powder cake.
• Stability of powder cake.
Fig. 2: Evaluation of collected cohesion measurement data
Carr's Indices (ASTM D-6393)
The flowability of bulk solids is correlated with the compaction properties using both the Hausner Index and the Carr Index which are found by using standardized tap density_cc781905-5cde-3194-bb3b-136badand58d.cf5 loose bulk density methods. As a result, an evaluation of powder flowability is provided using the FFI Flowability Index table after carrying out experiments. This kind of flowability evaluation is intended for low to medium cohesive powders .
norms
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EN ISO 787-11 Determination of tapped density
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DIN ISO 697 Determination of bulk density
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ASTM D-6393 Determination of Carr's Indices
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D-6773: Standard Shear Test Method for Bulk Solids
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ASTM D-7891 - 15 Standard Test Method
