Process for the manufacture of anhydrous sodium carbonate
AssigneeSolvay (Societe Anonyme)
InventorPhilippe Warny
Life of this patent
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Abstract
Process for the manufacture of anhydrous sodium carbonate, according to which a drier kiln including a rotary drum (1) is used, sodium carbonate monohydrate is introduced into an upstream region (4) of the drum, anhydrous sodium carbonate is collected in a downstream region (6) of the drum and a fraction of the anhydrous sodium carbonate is recycled from the downstream region into the upstream region, the recycling of the anhydrous sodium carbonate being performed inside the drum.
Claims13
A process for the manufacture of anhydrous sodium carbonate in a drier kiln while avoiding oxidation of kiln walls, said kiln including a rotary drum with an upstream region and a downstream region, comprising:
- introducing sodium carbonate monohydrate into said upstream region of said drum, collecting anhydrous sodium carbonate in said downstream region of said drum and recycling a fraction of said anhydrous sodium carbonate from said downstream region into said upstream region of said drum, said recycling of said anhydrous sodium carbonate being performed inside the drum while avoiding oxidation of kiln walls by avoiding entry of air into the drum.
A process for the manufacture of anhydrous sodium carbonate in a drier kiln and avoiding oxidation of the kiln walls, said kiln including a rotary drum with upstream region and a downstream region, comprising:
- introducing sodium carbonate monohydrate into said upstream region of said drum at a temperature of 80.degree. to 100.degree. C.,
- collecting anhydrous sodium carbonate in said downstream region of said drum at a temperature of 120.degree. to 180.degree. C., and
- recycling from 75% to 150% by volume relative to the volume flow rate of said sodium carbonate monohydrate introduced into the upstream region of the drum, of said anhydrous sodium carbonate from said downstream region into said upstream region of said drum, said recycling of said anhydrous sodium carbonate being circulated from the downstream region towards the upstream region of the drum by rotation of an Archimedes' screw housed in a tube arranged coaxially in the drum, the Archimedes' screw being integrally attached to the tube, which is integrally attached to the drum, while avoiding entry of air into the drum.
Dependencies are inferred from the claim text.