Method and apparatus for removing flotation material from the surface of liquid

摘要

A device to remove floating matter from a settling tank for waste water comprises a funnel 16 which is periodically depressed below the surface S to allow matter to flow over the whole periphery of the rim 18 to outlet 24. As shown the funnel slides vertically on pins 32 and is depressed against springs 34 by a motor 38 via a crank drive. The motor may be controlled to lower the funnel when a skimming blade sweeps matter towards it and to hold the funnel submerged for a time. In Fig 5 (not shown) the funnel is mounted by parallel links and adjusted by a screw drive. In Figs 6, 7 (not shown) a probe mounted on the funnel controls the drive to lower the funnel edge only just below the floating layer (cooking oil) to minimise overflow of water.