Chemistry of inorganic compounds – Phosphorus or compound thereof – Halogen containing
Patent
1990-02-14
1992-04-07
Lewis, Michael
Chemistry of inorganic compounds
Phosphorus or compound thereof
Halogen containing
23305A, 423121, 423127, 423629, B01D 902
Patent
active
051024268
ABSTRACT:
An improved process for precipitating alumina from Bayer process liquors is disclosed. The process involves dividing an incoming pregnant liquor stream into a minor portion of about 10 to about 25% of the total incoming pregnant liquor stream, and directing that stream into a series of small tanks where the minor stream is permitted to agglomerate. Fine aluminum hydroxide seed having a median particle size of between about 30 and about 60 microns is added to this stream. The slurry resulting from the agglomeration stage is then directed to a set of larger vessels in which the growth stage will take place. At this point, the remaining portion of the pregnant liquor is combined with the slurry resulting from the agglomeration stage. A coarse seed charge of about 150 to about 600 grams/liter of seed having a median particle size of between about 80 and about 100 microns is charged into the second set of vessels. This improved process helps to increase the yield of a strong coarse aluminum trihydroxide product.
REFERENCES:
patent: 2707669 (1955-05-01), Houston et al.
patent: 3486850 (1969-12-01), Day
patent: 3649184 (1972-03-01), Featherson
patent: 4234559 (1980-11-01), Tschamper
patent: 4305913 (1981-12-01), Anjier
patent: 4311486 (1982-01-01), Yamada
patent: 4512959 (1985-04-01), Pohland et al.
patent: 4614642 (1986-09-01), Cristol et al.
patent: 4617179 (1986-10-01), Veyrier
Sang, J. V., "Factors Affecting the Attrition Strength of Alumina Products", 1987 Light Metals, The Metallurgical Societ/AIME (Warrendale, Pa.), pp. 121-127 (Exhibit 7).
Audet Denis R.
Ellis Charles D.
Hiscox Bryan A.
Larocque Jacques E.
Alcan International Limited
Lewis Michael
Ngoc Ncog-Yen M.
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