Influences of seed size and number on agglomeration in synthetic bayer liquors

Abstract

By means of Malvern laser particle size analyzer and scanning electron microscopy, the influences of seed size and number on agglomeration in Bayer process were investigated. Agglomeration is almost finished in 8 h, seeds, below 5 µm, especially below 2 µm, gather together rapidly and almost disappear in 8 h. In the same supersaturation of aluminate solution and seed size, the smaller the number of seed is, the bigger the degree of agglomeration is. With the same primary number of seed, the agglomeration of larger seed is superior to that of small seed, and the agglomeration does not happen among the coarse seeds. The agglomeration mainly happens among fine particles, and the combinations among the fine particles are unconsolidated.

Keywords

bayer process / seeded precipitation / screen separation / agglomeration

References

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