A filter comprises a water permeable screen supported over a receiver and inclined to the horizontal. A header is provided for discharging water onto the upwardly presented surface of the screen at a rate such that the major part of the water passes into the receiver and a minor part of the water carries solid matter retained on the screen to the lower edge thereof. Brushes are provided for sweeping over the upwardly and downwardly presented surfaces of the screen to dislodge solid matter theref...

A method of manufacturing a filter media having plyed sections of obliquely oriented honeycomb cells is disclosed as well as a novel filter media of stacked sections of obliquely oriented honeycomb cells.

A filter characterized in that a plurality of screen plates each having a penetration hole at its central portion are disposed inside of a filter box in a stacked form with a distance between each other in such a manner that the penetration holes are aligned up-and down-wards. The raw liquid to be filtered is fed through said penetration holes and the filtrate is collected at plurality of portions disposed at a nearly equal intervals in the peripheral part of said screen plates.

A series type or parallel type multiple stage fluid filter wherein each stage of the filter includes a tubular coil, a porous filtering media disposed in layers and for filtering gases a cleaning liquid to a level above the porous filtering media through which the gases are passed for treatment. In a modification, means for cleaning the filter without removing it from its mounting are provided.

A filtering device wherein a nonwoven fabric is secured to a filter layer on the downstream side thereof for supporting the filter layer, the nonwoven fabric being provided with a plurality of intersecting slits which form flap valves which open to allow the passage of a gaseous medium through the device, the combined area of the flap valves being 35 to 60 percent of the area of the nonwoven fabric and the nonwoven fabric having a weight within the range of 13 to 34 grams per square meter. Prefe...

This invention relates to a filter for separation of solid and liquid from a muddy substance to be treated by a process of pressurization and dehydration thereof. The filter includes a group of pressure rollers located around the outer periphery of a rotary drum for providing a pushing force toward the center of the drum. A pressure belt, which may take an endless form, is interposed between the drum and the group of pressure rollers and is revolved around the drum. The clearance between the gro...

In filters of the type in which a cake of solids deposited from a liquid slurry thereof on a generally horizontal filter medium is subjected to treatment involving passage of liquid through the cake while on the filter medium, means is provided for increasing the drainage rate of the formed cake by causing the cake to form on the medium from the slurry fed thereto by gravity settling in the liquor of the slurry and by removing liquor of the slurry from above the cake while the liquor still conta...

The cylindrical filter surface of a drum filter is increased in effective area by providing radial inward and outward undulations in the general cylindrical shape instead of the cylindrical surface of the prior art.

In filters of the type in which a cake of solids deposited from a liquid slurry thereof on a generally horizontal filter medium is subjected to treatment involving passage of liquid through the cake while on the filter medium, means is provided for increasing the drainage rate of the formed cake by causing the cake to form on the medium from the slurry fed thereto by gravity settling in the liquor of the slurry and by removing liquor of the slurry from above the cake while the liquor still conta...

An improved filter is described for use in filtering liquids where a typical use would be filling small water tanks as used on yachts or campers and the like. The filter includes a mechanical filter in the form of a knitted or woven cloth member positioned in series with a chemical filter comprising activated carbon. The cloth filter is positioned in advance of the carbon filter and is arranged so that it may stretch during the life of the filter to compensate for the accumulation of filtered pa...