Abstract: An arrangement for scraping the filtered solids build-up from the surface of a drum filter is disclosed, in which a scraper is mounted with an edge against the surface so that rotation of the drum will accomplish scraping of the surface. Clutching engagement with a rotary drive member is produced by a predetermined extent of axial shifting of the drum against the resistance of a spring bias force. The drum is also arranged to be subjected to an axial pressure force developed by flow through the filter so that clutching engagement is automatically produced upon build-up of solids to a predetermined extent to cause a level of pressure force to be developed to produce a consequent axial shifting sufficient to produce clutching engagement and rotation of the drum. A drag out conveyor moving through the tank engages a rotary sprocket which comprises the rotary drive member, and the scraper edge and drum are positioned to directly deposit the scraped solids on the conveyer to be removed from the tank.

Abstract: A method and apparatus are disclosed for removing paint overspray suspended in air exhausted from a paint spray booth, in which the exhausted air is drawn through a conveyor-carried bed of small diameter beads or granules of plastic or other material allowing only a mild adherence of the paint to their surfaces upon drying. The paint overspray is removed from the air by being deposited on the surfaces of the beads as the air passes through the beads and paint is subsequently rapidly dried on the bead surfaces in a drying chamber. The paint carrying beads are then mechanically agitated to dislodge the dried paint to clean the beads for reuse, and the dislodged paint particles are separated from the cleaned beads for collection and disposal.

Abstract: A filter of the type including a filter drum mounted within a settling tank containing a liquid to be filtered, with filtering flow drawn through a filter media on the outer surface of the drum, in which a fluid connection to the liquid circulation system is established by interfitting of tube sections as the filter drum is lowered into the tank at installation. Guiding members are included to properly position the drum as it is lowered to insure the tube sections move together as the filter drum is lowered. A valving arrangement is disclosed in one embodiment for isolating the particular drum filter from the circulation system upon removal. In another embodiment, an arrangement is utilized for producing intermittent rotation of the drum by engagement with the flights of a drag-out conveyor.

Abstract: A drum filter is disclosed mounted vertically within a tank which receives the liquid to be filtered. The drum is provided with inside and outside filter media layers and intermediate axially extending passages receiving filtered liquid flow, which is collected in a central tube extending vertically upward and adapted to be connected to a suction pump.A backwash arrangement includes a backwash flow passage directing flow successively through each of the axial passages as the drum is incrementally rotated about its axis.Collection troughs are positioned extending axially along the inside and outside periphery of the drum member so as to receive the backwashing flow and contaminants, with a flushing flow carrying off the contaminants from the tank for secondary filtration.The rotary indexing drive consists of a cylinder actuated ratchet drive with a sprocket wheel in engagement with a chain track located about the interior diameter of the drum member at its upper end.

Abstract: A liquid filter is disclosed including a filter chamber into which extends a looped endless belt which is passed above and below rollers on either side of the filter chamber. Both the upper and lower belt segments pass over a support plate in the filter chamber, the lower segment positioned directly underneath the upper belt segment. Filtering flow from the filter chamber passes through both belt segments and through spaced and tapered openings in the support plate and then into a collection trough beneath the support plate. The belt is periodically advanced to carry filter solids out of the filter chamber. In a first version, the upper belt segment acts as the filter media, and is wider to create a sealing of the lateral edges of the upper belt segment. In a second version, a disposable media lies atop both belt segments which act only to carry the disposable media and the disposable media is of wider width to establish the edge sealing.

Abstract: A belt type filter is disclosed in which a length of disposable filter sheet material is dispensed from a roll to extend through the interior space of a tank, over a pervious section of the tank bottom communicating with a collection chamber receiving filtered liquid from the tank after passing through the filter belt.The filter belt side edges extend within recesses along either side of its path through the tank interior space with an inflatable seal extending along each recess to secure and seal the edges thereof at all points below the level of liquid in the tank. The filter belt is periodically advanced to dispose a fresh section of filter over the collection chamber either manually or under automatic control sensing the vacuum generated by a circulating pump connected to the collection chamber.

Abstract: A fully submerged rotatable drum type of filter has a perforate cylindrical surface through which contaminated liquid is pulled by a suction pump. The inner periphery of the drum is sub-divided into numerous narrow, shallow, elongated chambers open at one end for communication with a main chamber which conveys filtered liquid to a port in the non-rotatable tube upon which the drum is rotatably mounted. A backwashing system for cleaning the perforate surface of the drum comprises a non-rotating channel which establishes sliding and sealing contact with a limited number of the open ends of the peripheral chambers to cause pressurized filtered backwashing liquid to flow into such peripheral chambers to remove filter cake from the perforate surface by the reverse flow therethrough. Filtration can therefore proceed through a majority of the peripheral chambers simultaneously with the backwashing operation through the limited number of peripheral chambers in communication with the backwashing system.

Abstract: Contaminated liquid is filtered through a conveyor-driven endless loop filter belt which surrounds a filter box submerged in a tank of the liquid to be filtered. The liquid is caused to flow through the filter belt and into the perforated upper and lower walls of the box by means of pump-induced static pressure differential. After predetermined build-up of filter cake on the filter web over the filter box inlets, control means index the filter web to bring clean web into registry with the filter box inlets. Improved means for preventing contaminated liquid from by-passing the longitudinal edges of the filter belt comprise longitudinally extending expandable tubing which can be pressurized to firmly clamp the filter belt edges against a rigid reaction surface.