Improvements in and relating to the conditioning and filtration of water and other liquids

摘要

687,675. Purifying water; gravity sand filters; gravity-separation apparatus. HILL, F. G. Sept. 19, 1950, No. 23003/50. Addition to 675,322. Class 46 The plant of the parent Specification is modified by providing a localized lower cut-away portion in the laterals or distributing conduits to enable liquid to pass substantially freely upward into them. The laterals may alternate with or be replaced by pipes formed of non-corrodible material. One, or more of the flocculating, clarifying and filtering sections of the plant is provided with a downflow compartment the lower end of which corresponds to the cutaway portion of the distributing conduits. Water passes into theclarifier section 2, Fig. 4, along an inlet channel 10 communicating with cutaway portions 5a, 6a in concrete laterals 5 and pipes 6 respectively, Fig. 11, to flow into and along the laterals and pipes and. out again through longitudinal series of openings into the main part of the section on either side of the channel 10. It flows out by channels 15 which join to form the inlet channel 17 of the filter section 3, Fig. 5, where the same kind of flow takes place, the water eventually rising between laterals 18 and grid pipes 19 and 21, Fig. 7. The pipes 119 are formed in pairs, Fig. 9, with the small pipe 21 forming narrow spaces, with adjacent pipes of each pair to support the filter medium, and are joined by transverse conduits 19b having fixing holes 19c. Water may be passed down pipes 24, Fig. 5, into one or more pairs of pipes 19 connected in parallel and out through holes provided in the lower walls of the pipes 19 for localized backwashing. The wash water may be mixed with air or replaced by steam or a liquid containing a sterilizing agent. For cleaning the whole filter section a wash water ;pipe 27 fitted with an aerator 27a is provided in the downflow channel 17. A portable cleaner 28, Fig. 13, having an aerator 29a in its down pipe 29 may be placed below the filtering medium and moved about while wash water or the like is supplied to the pipe 29, the cleaning being performed either while static water is above the medium or while a. backwash is in operation.