公开(公告)号：US5158577A

公开(公告)日：1992-10-27

申请号：US665340

申请日：1991-03-06

Applicant: Bruan A. Hiscox ,  Charles D. Ellis ,  Jacques E. Larocque ,  Denis R. Audet

Inventor： Bruan A. Hiscox ,  Charles D. Ellis ,  Jacques E. Larocque ,  Denis R. Audet

IPC: C01F7/14

CPC classification number: C01F7/144 ,  C01P2004/61

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% by volume 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.

Abstract translation: 公开了一种从拜耳法溶液中沉淀氧化铝的改进方法。 该方法包括将进入的怀孕液流分成总进入的怀孕液流的约10至约25体积％的小部分，并将该流引入一系列小容器中，其中少量流被允许聚集。 将中等粒度为约30至约60微米的氢氧化铝细粒子加入该料流中。 然后将由聚集阶段产生的浆料导向一组较大的容器，其中将发生生长阶段。 此时，将剩余部分的怀孕液与由聚集阶段产生的浆液组合。 将约150至约600克/升中值粒度为约80至约100微米的种子的粗种子装料装入第二组容器中。 这种改进的方法有助于提高强大的三氢氧化铝粗产物的产率。