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The Al2O3 , CaCO3 , and Talc are used as experimental samples
to study the mechanism of centrifugal dewatering.
This study is divided into two parts. In the first part we used
the Al2O3 which form a incompressible cake.From the
experiment we found that most of the
dewatering of Al2O3 cake is in the funicular
state,therefor the relationships between the capillary
pressure and the saturation of cake can be
regressed as power type,while the
permeability and the saturation of curve is exponential
type.In the second part we used the powders which
could form compressible cakes as our
samples, including CaCO3 and Talc .The major dewatering
mechanism of CaCO3 was the compression of
cake, so the saturation would eventually be
1.Talc was the sample which had compressive and
centrifugal dewatering effects at the
same time.Comparing the dewatering rate of
these two effects, we found that compressive dewatering
was 1-1.5 times to pure centrifugal
effect.
Compressive effect took place ony in the beginning of
dewatering, and it would decrease the
porosity.By the variation of porosity , we
could use the empirical equation of expression to find the
value of solid compressive pressure, and to
predict the compressive rate.
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