Patent GB-764499-A (GB)
Title: Improvements in or relating to filters
IPC: B01D29/39
Filed: 1954-06-14
Abstract: 764,499. Filters. TEATINI, D. June 14, 1954 [June 16, 1953], No. 17481/54. Class 46. The casing comprises an upper hemicylindrical part 6, Fig. 2, integral with a vertical head 1, Fig. 1, and an inclined head 2, and two quartercylindrical parts 7, 8, each hinged at 9 or 10 along an edge of the part 6. The free edges of the parts 9, 10 may be secured together by hooks 11 integral with a rod 12 rotatably supported between feet 3 and 4, Fig. 1. Valved pipes (not shown) communicating with a fourway connector la provide for admission of liquid to be filtered at 14 and hot washing water at 15, and for discharge of liquid from the casing at 16. The easing 6, 7, 8 is surmounted by an extension 17, Fig. 2, closed by a hinged lid 18 and provided with an air-venting pipe 21, Fig. 1, and a rotatable pipe 33 with nozzles (not shown) for washing the filter cloths. Each filter element 5 may comprise a pair of annular, elliptical, perforated plates 42, 43, Fig. 6, soldered together at their outer peripheries 44, and at their inner peripheries 37 to leave a hole 39 to facilitate penetration of liquid between the elements. Filter cloths 60, 61 are held in place by rings 40, 41. Each element 5 is supported by two short pipes 23, Fig. 2, each of which is mounted. so as to permit swinging of the element on one of two pipes extending through one of the walls 17 : a pipe 25 communicating with an outlet manifold 55 for filtrate, and a pipe 24 communicating, in the case of odd-numbered elements only, with an inlet manifold 32 for washing liquid. When the casing is closed the elements are constrained by their shape, relative to that of the casing, to assume the positions shown in Fig. 1. Liquid to be filtered is introduced at 14 and fills the casing, a cock 22 on the pipe 21 being thereupon closed. Liquid is passed in and filtration continued until the spaces between adjacent elements are wholly occupied by filter cake. Hot water is then introduced at 15 and displaces liquid remaining in the cakes and elements through the manifold 55. Introduction of hot water at 15 is discontinued, and thereafter the washing of the cakes is completed, and washing of the insides of the elements effected, by introducing washing liquid from manifold 32, Fig. 2, into the odd-numbered elements, the outlet cocks 28 of which are all closed by cams 31, and withdrawing it through pipes 23 and 25 of the even-numbered elements, cocks 28, and the manifold 55. Next, the hooks 11 are released, permitting parts 7, 8 to fall to positions 7<SP>1</SP>, 8<SP>1</SP>, Fig. 2. The elements are then swung downwards to vertical position by movement of two pneumatically-operated toothed bars 26, Figs. 2 and 3, one on each side of the casing, which are in engagement with the elements. This operation serves to increase the perpendicular distance between adjacent elements and thus to detach the cakes. The filter cloths are washed with water under pressure supplied to pipe 33, after which the elements are restored by the bars 26 to their inclined positions and the casing closed. In Fig. 7, the casing is in two parts : an upper part 45, integral with head portions 46 and 47 on supports 48 and 49, and a lower part 50, rotatable about a pivot 51 by a servomotor (not shown), and constituting in its open position a channel for guiding cakes and water during discharge. The pipes 24, 25, Fig. 2, may be withdrawn outwards to permit assembly or disassembly of the elements 5.