GB1266572A - - Google Patents

Abstract

1,266,572. Aerating liquids. SANITARY DISPOSAL SYSTEMS Inc. 6 March, 1969 [7 March, 1968], No. 12049/69. Heading B1C. [Also in Division Cl] Apparatus for aerating sewage comprises a vessel having two coaxial internal annular walls 58a, 64a (as shown, frusto-conical) forming an annular passage 70 to which air is supplied by ring diffusers 72, 84, 86. Sewage enters at 56 and circulates down through the turbulent zone 152 and up the annular passage 70. Heavy solids are deposited within the upstanding wall 22 and may be periodically removed through pipe 34. Lighter particles circulate until they pass beneath wall 58a into chamber 90 when they are arrested by the submerged biological filter 128. The liquid then passes over adjustable weirs (104, 106, see Figs. 2-4, not shown) into the ends of trough 114, down through pipe 116 into a sector-shaped chamber 98 defined by vertical walls (92, 94, Fig. 2, not shown), up through sand filter 124 and out through pipe 48. The effluent is treated by ultra-violet light sources (132, Fig. 3, not shown) placed over the trough 114 and by potassium permanganate, or by chlorine vapour passing through a wick the end of which enters pipe 116. The temperature in chamber 98 is controlled by a heater 156 and thermostat. There may be a second pair of annular frusto-conical walls 58b, 64b. There is a siphon 120. The diffuser rings may have air escapes which consist of a threaded aperture closed by a loosely fitting screw (see Fig. 6, not shown) or by a bolt (146, Fig. 5, not shown) having a longitudinal slot (150) in the threaded portion and secured by a lock-nut (148), the size of the air escape being dependent on the adjustment of the bolt.