✗ˈᖃ❵✗ᶑԦ䘹ᤙޕᯉ㋂ᓖ D90 Ѫ 8.76 μmǃ❵✗ᓖѪ 950 ćǃᚂᰦ䰤Ѫ 3 h
ީ 䭤 䈃φ➔⸨⸣˗儈ዝ൏˗ᐕ㢪ⸯ⢙ᆖ˗᩷ᒺ࠶䘹˗ᗳ࠶䘹˗❵✗ⲭ
theoretically, the calcination whiteness of the product can reach more than 85%, and the
yield can reach 81.37%.
The optimum processing condition of table separation is determined. When the angle is
5°, the stroke is 10 mm and the runs frequency is 350 times/min, the calcination whiteness
of the kaolin product reaches the highest value of 85.10% and the yield is 50.19%. The mass
rate of Al2O3 is 37.26%, and the recovery of Al2O3 is 53.40%. And the total removal rate of
TiO2 and Fe2O3 reaches 69.21%.
The results of centrifugal separation test show that when the rotary speed is 800 r/min,
the feeding speed is 8.4 L/min, the feeding concentration is 20% and feeding time is 100 s,
the calcined whiteness of kaolin product reaches the highest value of 78.80% and the yield
is 86.31%. The mass rate and the recovery of Al2O3 are 35.62% and 87.79%, respectively.
And the total removal rate of TiO2 and Fe2O3 is 34.16%.The whiteness of kaolin can be
improved obviously by high temperature calcination. And the whiteness of the calcined
product can reaches 85.93% when the mass rate of particle size less than 8.76 mm reaches
90%, the calcination temperature is 950 ć and the constant temperature time is 3 h.
The experimental results show that some iron and titanium impurities can be removed
from coal gangue by centrifugal separation and table separation. Further fine grinding and
high temperature calcination of kaolin after separation can improve the calcination
whiteness of kaolin to a great extent. The research could provide a technological scheme for
the preparation of high quality kaolin products from coal gangue which will