| 摘要 |
<PICT:1085760/C1/1> <PICT:1085760/C1/2> <PICT:1085760/C1/3> Apparatus for the surface aeration of sewage in a tank comprises a rotatable agitator disc 22 mounted at the liquid surface above an uptake chamber 25, and having detachable projections 24 (which may be rubber spheres) dipping into the liquid. In operation liquid spray is projected radially outward and entrained with air induced down the trunk 31 and under the fixed annular disc 26 by fins 221 on the upper surface of the disc 22. A fixed annular disc 28 forms a spray shield and reduces foaming. The height of the agitator disc 22 and driving motor 11 relative to the liquid surface is adjustable, as is the height of the annular discs 26, 28 relative to the agitator. The apparatus may be incorporated in an installation for purifying sewage, see Fig. 6, in which it is pumped from a sump 33 to a sand removal tank 36, screen filter 37 and constant delivery tank 32; after treatment the water passes to a primary decanter 42 whence the sludge may be recycled through pipe 45. |
