GB1429855A - Filter press - Google Patents

Abstract

1429855 Filter presses ISHIGAKI KIKO KK [trading as ISHIGAKI KIKO CO LTD] 6 March 1973 [6 March 1972 3 July 1972] 10873/73 Heading B1D In a filter press the filter cloths, the top and bottom ends of which are attached respectively to upper and lower bars which are connected to driving means via elongated flexible media (e.g. belts, chains, ropes), have cakes removed therefrom by moving them past scrapers or brushes positioned below the plates of the press. During at least a substantial part of the time cakes are being removed from the cloths the lower bars are raised and the upper bars are simultaneously lowered. After cake removal the cloths may be sprayed with water on their return travel. In the embodiment shown the filter press comprises plates 3 which are clamped and separated by a piston-cylinder mechanism (not shown). The filter cloths 11A, 11B are connected at their ends to bars 12, 13 and entrain rollers 14, 15 respectively. The bars are connected to chains 21 which entrain sprockets 20 which are driven through bevel gears 25, 26 from driven shaft 27. Each plate 3 comprises peripheral members 29 and 30, partition 31 and diaphragms 32 (e.g. of rubber, synthetic resin) provided with projections providing filtrate passages therebetween. In use with the plates clamped, slurry is introduced between each pair of adjacent cloths 11A, 11B by a slurry feeding device 39 comprising pivotable portions 39a, 39b attached to cloths 11A, 11B respectively, which device 39 receives the slurry via openings 38 in the plates and openings (41, not shown) in the cloths from pipes (36, not shown) connected to the plates. The filtrate passing through the cloths is discharged via the passages on the diaphragms 32. The filter cake is pressed further by forcing compressed water behind the diaphragms 32. This water is then discharged by compressed air and the plates are separated. The filter cloths are then moved past scrapers 47, 48 and the device 39, which is opened as it moves downwards with the cloths, 'and the cloths are sprayed with water from nozzles 49-51. In other embodiments, each cloth may be attached to a separate pair of bars 12, 13; the press may comprise alternate plates and frames; the plates may be separated individually; and the slurry feeding devices may take different forms. In another embodiment each cloth may be wholly positioned on one side of a plate and the scrapers may be spring loaded to allow them to be moved out of the way when the lower bars are moved around the rollers 14, 15.