GB502962A - Improvements in or relating to the purification of water for consumption and of waste water - Google Patents

Abstract

502,962. Filters ; manures. EAU ET ASSAINISSEMENT, ANCIENS ETABLISSEMENTS C. GIBAULT. Aug. 23, 1937, Nos. 23041 and 23042. Convention dates, April 19 and June 3. [Classes 46 and 111] Drinking water or waste water is filtered downwards through a bed of absorbent material supported on a perforated plate below which a reduced pressure is maintained by a suction device, such as a fan, so that air passes from the top to the bottom through the whole of the bed. The bed may consist of cellulose or of materials, such as rags, paper, or garbage, the main ingredient of which is cellulose. Other suitable materials are asbestos, slag wool or other mineral wool, coal, charcoal and clinker. Layers of different materials may be used. The materials used may be impregnated with alumina, carbonate of lime, permanganate of potash, ferric hydrate, or aluminium silicate. Agents such as carbonate of lime, aluminium hydrate, ferric hydrate, aluminium sulphate and perchloride of iron may be added to the water before filtration. The filtering-media after use in the process can be regenerated by aeration continued after the supply of water has been cut off. The upper layer of the bed can be loosened by hand or mechanically. Cellulosic material which has become charged with nitrogen can be aerated until a mould has been formed which can be used in agriculture. This may be done in the filter or the material can be removed to a fermentation cell. Fig. 1 shows a bed 3, the space beneath which is connected to a suction device by a pipe 7 fitted with a pressure gauge 12. The water to be treated is supplied through a pipe 4 and treating-agents from a pipe 6. The filtrate is discharged by a conduit 9, from which some of it may be returned to the filter by a pump 11. Fig. 2 shows a filter 15 with air suction pipe 19 from which the filtrate is discharged by a siphon 20 into a filter comprising a cloth bag 23 on which a membrane has been formed, as described in Specification 501,334, by means of colloidal matter poured in through a funnel 24. The bag 23 may be filled with any of the filtering-media mentioned above. The Specification as open to inspection under Sect. 91 describes also apparatus shown in Fig. 3 (Cancelled) comprising an aerating column 28 and an upward flow filter 44. Water enters the column 28 through a pipe 32 and compressed air through a perforated pipe 29. The liquid is passed on through a pipe 36 to which treating agents are supplied from a funnel 38 and by a pump 40 from a vessel 41. In the filter 44 the water passes through a bed of filtering media on a support 45 and through a cloth 46 on which a filtering-membrane has been formed as described in Specification 501,334. Compressed air may be introduced at the base of the filter. This subject-matter does not appear in the Specification as accepted.