| 摘要 |
A filtering apparatus for liquids, based upon the structure and technology of ascending-flow deep filters of the continuous-backwash type, equipped with means for continuous self-regeneration of the filter bed, whether this be constituted by active material or inert material, of the type comprising a vertical cylindrical tank (1) having the bottom part that narrows in the form of an upturned truncated cone (3a) or that narrows by means of a crowned end plate, where the liquid to be filtered, referred to as "influent", is fed through an inlet (4) and evenly distributed over the filter bed from the bottom of the unit through a distributor (5) in which the liquid flows upwards traversing the filter bed (8) and is discharged from the filtering apparatus through an outlet overflow (9) for the effluent, regulated by an overflow, which determines the static level (10) of liquid present in the filter; where the granular particles that constitute the filter bed and the possible solids trapped therein are drawn downwards and then sent towards the top of the filter by a purposely provided lifting device referred to as "airlift" (11) present in the proximity of the bottom of the tank (1) and positioned at the centre of the filter; where the granular particles drawn downwards and lifted by the airlift free the trapped suspended solids; and where the granular particles at a high sedimentation rate are left to fall back onto the filter bed (8), thus reconstituting it, whereas the particles with a low sedimentation rate, i.e., the suspended solids that have been freed, are discharged into a purposely provided conduit (26); thus obtaining a backflow filtering: the influent, rich in suspended solids and/or dissolved substances, in its ascending motion encounters in the first filtering steps the granular filtering medium that, with descending motion, prepares to undergo the cleaning steps so that a large part of the pollutant charge is immediately removed from the filter bed, said filtering apparatus being characterized in that to apply regeneration of the filter bed in the filter itself, provided at the intake mouth of the airlift device (11) is a purposely designed washing and contacting chamber (22), referred to as "contacting reactor", and in that provided at the other end of the airlift device is a separation and finishing section (15 and 18), referred to as separator reactor. |
