GB191414976A - Improvements in and relating to Pressing Apparatus for Separating Solids from Liquids and for other purposes. - Google Patents

Abstract

14,976. Berrigan, J. J. June 30, 1913, [Convention datel. Filter-presses.-A pressing - apparatus, described in connexion with a bag filter, consists of one or more pairs of pressing-members pivoted together and adapted to move downwards under the action of gravity or other vertical force, meanwhile moving also towards each other with a gradually decreasing angular swing about their pivot. In the form shown in side and end views in Figs. 1 and 2, the pressing-platens 1, 1<a> are pivoted together at their upper ends and are trunnioned at 11 in links 12, which are attached to shafts 13<a> journaled in boxes 13 on the foundations 14. The boxes 13 have heads running in T-slots 16 in the foundations, and they are connected by ties 17, the nuts 18 of which enable the distance between the boxes to be adjusted. The hinge-joints between the platens are yielding, and each consists of a rod 2 pivoted at 3 to one platen and passing through a pivoted sleeve 4 on the other one. Nuts 7 and springs 8 give an adjustable yielding pressure between the platens, simultaneous adjustment at both ends being ensured by coupling the nuts by a sprocket chain 10 or the like. The weight of the platens causes them to fall inwards towards each other while swinging the links 12 about their pivots 13<a>. Gravity may be assisted by bringing fluid pressure through a cock 30 at each end of the press to the upper side of a piston 21, the rod of which is coupled at 23 to the Jinks 12. The cylinders are connected at their lower ends by a pipe 25, an offset 26 of which has a needle valve 27 for controlling the rate of closure of the platens, and a valve 28 for introducing fluid pressure for opening the platens. Manipulation of the valve 27 enables a slight initial squeeze to be followed by heavy pressure, as sometimes required in filtration, The platens may be hollow for steam-heating, and, as shown in Fig. 4, they may be adapted to treat the pressed cake with gas, acid, or washing-water. For this purpose, their faces behind the perforated plates 31<a> have vertical channels 31 of known type joining horizontal channels 32, 33, into which the supply inlet and outlet pipes 34, 35 lead. The cocks may be coupled, as by a rod 37<b> abutting on the base of the press, so that as the platens descend, the valves are automatically operated in the proper sequence, for example for washing the cake. The expressed liquid may be received in a tray 42, Fig. 1, running on wheels on rails 44. Several pairs of platens may be combined, as shown in Fig. 7, in which form the brackets 54 in which the platens are pivoted move inwards towards each other as they move downwards. They may be pivoted together at their bottoms or tops so as to move angularly about their pivots while rising or falling. The filter bags or the like may be supported by being squeezed between the top edges of the platens, as shown in Fig. 3, and they may rest on plates 55 carried by links 55<a> pivoted together and to the platens at 56. A bag outlet 58 may be provided, particularly where it is required to withdraw the material in a semi-fluid condition after expressing part of the liquid. A coarse inner bag may be used with a smaller outer bag of finer texture. A form is also described in which the platens are pivoted together at the bottom, and the filter bag is introduced into the resulting V - shaped opening from above and is supported by flexible hangers attached to clamps on the upper edges of the platens. The bag may have an inlet at the top and an outlet at the bottom, whereby several charges may be successively pressed and a cake built up to any desired thickness. Specification 18,584/12 is referred to.