Experiments to Study Attrition Mechanisms

Attrition cannot normally be directly investigated in the large-scale process. It is, for example, impossible to analyze the whole bulk of material and it is nearly impossible or at least very expensive to vary parameters in a running industrial process. For that reason, attrition has to be investigated in small-scale experiments. The results of these experiments require a model or at least an idea of the governing attrition mechanisms to be applied to the large-scale process. In principle, there are two different philosophies of attrition modeling. 

The most commonly used philosophy is to design a test facility that simulates the relevant process stress. Examples of such test facilities are the various jet attrition test devices which are used in fluidization technology. 

The results can either be directly extrapolated to a large-scale process or reveal relationships which may serve as guidelines in the design of this process. It should be noted that most of these tests are batch tests, but most full-scale processes are continuous. So, the transfer of the results can be difficult due to the time dependence of the degradation. 

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