PURPOSE: To efficiently remove C compounds by adjusting the molar ratio of an Al component/an Na component in a Bayer circulating liq., heat treating the liq. to remove the contained C compounds, dissolving the residual solid in a Bayer circulating liq., and adding the resulting slurry to a Bayer circulating liq. to be treated as an alumina source.
CONSTITUTION: The molar ratio of Al2O3/Na2O in a Bayer circulating liq. or its concentrate contg. Al components, Na components and C compounds in a stage for manufacturing alumina by the Bayer process is adjusted to 1W5, especially 1W2. The adjusted liq. is heat treated at 500W1,350°C to remove all of the contained C compounds as gaseous CO2. The residual solid contg. sodium aluminate after heating is dissolved in a Bayer circulating liq. contg. preferably no solid and subjected to solid-liq. separation. The resulting slurry contg. the undissolved solid is mixed with a Bayer circulating liq. as a liq. to be treated in said stage for treating C compounds. The slurry is used as an alumina source in the stage.
YAMADA YASUNORI
ARAKAWA NORIO
| JPS5510461A | 1980-01-24 |
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