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Schüttgut-AnalyseAnalysis of bulk solidsAnalyse de solides en vracAnalisis de sólidos a granel
solids solutions group

Analysis of bulk solids

First and foremost, an analysis of the bulk goods to be conveyed is required in order to choose the appropriate procedures/systems and components

Geldart divides the bulk cargos according to their fluidization behaviour and air retention into the groups A, B, C, D, providing a rough classification of the conveying characteristics


A     fine-grained powder with low density, easily fluidised with 
       good air retention

B     medium granulation with medium density, some 
       fluidisation properties with poor air retention

C     fine powders with higher density, cohesive, poor 
       fluidisation properties with poor air retention

D     larger granulation with higher density, no fluidisation properties, no air
        retention

Jenike describes the flowability of the bulk goods using the yield function FFC, providing a rough classification of discharge behaviour from tanks. His classification is:

Freeflow                         10 ≤ FFC < ∞
Flow                                  4 ≤ FFC < 10
Cohesive                           2 ≤ FFC < 4
Very cohesive                   1 ≤ FFC < 2
Non flow, hardening               FFC < 1


The conveying characteristics and the discharge behaviour from tanks are both relevant for the planning of pneumatical plug conveying, and therefore must be included in the evaluation.

Additionally the nature of the task and the specific requirements such as the maintenance of the product characteristics, granulation, volume, bulk weight, no contamination etc., have to be considered.

 Analysis of bulk solids