GB1414755A - Mixing apparatus - Google Patents

Abstract

1414755 Mixing and aerating apparatus; froth flotation apparatus BOLIDEN AB 17 April 1974 [19 April 1973] 16737/74 Headings B1C and B2H An immersion mixer comprises a rotary disc agitator 14 having on its underside radial straight or helical vanes 21, and at least one elastic self-closing nozzle 22 with a preferably vertical slot - shaped opening 24 for supply of a gas or liquid treating medium. There may be a ring of stator vanes 23. The vanes 21 extend at least 50% and preferably 60-90% of the distance between the centre and periphery of the agitator; the nozzle opening is arranged 0.1 R to 0.5 R from the agitator axis and 0.1 R to 0.33 R below the lower edge of the vanes 21, where R is the agitator radius. As shown there is a plurality of downwardly-sloping nozzles 22 detachably arranged on an annular manifold 25 (see also Figs. 3-5, not shown); they may be of neoprene rubber. The vessel 10 may have a rubber lining 13, the fluid supply pipes 26 be rubber covered, and the manifold 25 be of rubber with a metal reinforcing ring (34). The vanes may decrease in height towards the periphery of the agitator, preferably to such an extent that the cross-section of the channels between them also decreases. The apparatus may be used for aeration of sewage or in froth flotation.