| 摘要 |
<p>1,110,753. Filtering apparatus. DOUCET S.A. 28 June, 1965 [1 July, 1964], No. 27282/65. Headings BID and B1T. A fluid to be filtered is delivered to the upstream side of a filtering wall 48, which is thereby maintained in vibration to detach impurities therefrom, and a proportion only of the incoming fluid passes through the wall, the remainder sweeping across the upstream face to remove detached impurities from the filter housing. The filter wall may be cloth or metal gauze, and the vibration is effected by narrow apertures 57 through which the incoming fluid is directed approximately parallel to the filtering surface. In the embodiment of Figs. 8-10, the filtering element 48 is of tubular, octagonalsection form and apertures 57 are circumferentially spaced about the upper and lower ends of the element. The incoming fluid is delivered from pipe 58 to conduit 46, 47 and the filtered fluid leaves by conduit 61. At circumferentially spaced locations intermediate of apertures 57, the annular space 50 communicates with outlets (59), 60 for the fluid used to sweep the upstream surfaces (Fig. 10 not shown). In addition an air vent 62 is supplied whereby the filter housing may be drained, prior to directing jets of cleaning fluid from nozzles (52) carried by a central tube 51 (Fig. 10 not shown) onto the downstream side of the filter element 48 whereby the element is backwashed. The said cleaning fluid may be heated, supplied under pressure, and may contain solvents or acid. Supply of the cleaning fluid through conduit 56 causes the tube 51 to move axially upwards in cylinder 54, the rate of movement being limited by outlet 63 above the upper closed end of the tube 51, this movement allowing the jets of clean fluid to cover the whole area of the filter element 48. Alternatively the tube 51 could be rotated. In an alternative embodiment (Figs. 2-7 not shown) the filter is constructed in the manner of a filter press, with flat filtering elements (15) being clamped between two different forms of annular elements (10), (11) arranged alternately. Elements (10), (11), (15) all have co-operating through holes, which, when the filter is assembled, form axially extending ducts whereby the fluid to be filtered is supplied to the interior of elements (10), part of it sweeping over the elements (15) and being removed from said interiors, while the remainder passing through the elements (15) and is withdrawn from the interiors of elements (11). The filtrate receiving elements (11) are supplied with air inlets for expelling the fluid prior to cleaning, and with centrally mounted jets (33) for delivering the cleaning fluid. The cleaning fluid may be liquid or gaseous or foam. and the cleaning action may be initiated at regular intervals by a timer or in response to an increase in pressure drop across the filter. The jets of cleaning fluid may cause the filter elements to vibrate, in a similar manner to the fluid being filtered.</p> |
