Abstract: A removable culvert grate for placement adjacent the inflow end of a culvert. The grate includes a vertical grate having a plurality of slats to prevent the flow of beaver workings or similar debris therethrough, and a horizontal platform extending outwardly from the lower edge of the vertical platform. A linkage bar is provided extending from the upper edge of the vertical grate for connection to a power source such as a winch. The grate may be placed adjacent the inflow of a culvert, and, after beavers have constructed a dam or similar debris has collected against the vertical grate, the unit may be lifted by a winch carried in a pick-up truck or similar vehicle, carrying with it the debris.

Abstract: An endless filter belt is guided and supported by rollers or non-rotatable guide bars so as to have an upper run which extends above a substantially horizontal drainage plate to which a vacuum may be applied to draw liquid downwards therethrough. The upper run of the belt is shaped by movable guide means, e.g. pivotal arms which raise and lower the respective ends of the upper run and elements which depress a central region of the upper run into contact with the drainage plate, so as to form a receptacle into which a batch of material to be filtered can be placed. After filtration, when vacuum is no longer applied to the plate, the belt is progressed and any filter cake is removed at another location, a fresh section of belt then being available to form another receptacle.

Abstract: A reverse osmosis (R.O.) water purifier system that collects and stores pure water at low pressure and dispenses it at high pressure. Impurities left behind when the water passes through a R.O. module are disposed of by two methods: the fast flush method and the slow flush method. In the fast flush method, water entering a R.O. module may take two paths to escape therefrom. The first path constrains it to travel through a semi-permeable membrane in the module which filters out undissolved solids and which restrains the passage of dissolved liquids. The second path allows it to travel through the R.O. module, without passing through the membrane, thereby carrying out those impurities left behind by the water passing through the membrane. The purified water is directed to one side of a compartmented storage tank and the waste water from the module is directed to a control valve.

Abstract: An apparatus is disclosed for feeding a rotary filter with suspension by continuous flow to separate the solid and liquid phases of the suspension. The rotary filter apparatus includes at least one disc having filtering surfaces formed of a plurality of sectors fixed on a hollow horizontal driveshaft passing through the axis of the disc. The sectors are arranged to dip sequentially into a trough containing the suspension. The driveshaft serves for discharge of the liquid phase, and includes distributor means providing filtration, drainage and blowing stages acting sequentially on the sectors during the rotation of the discs.

Abstract: A tamper resistant animal guard for a drain pipe outlet having self cleaning prongs for preventing the admission of small animals while allowing sticks, leaves and other debris to flow from a drain pipe is provided by the utilization of a plurality of individually rotatable prongs axially disposed on an axle or shaft. A mounting bracket for mounting the axle or shaft is preferably of a flexible material to conform to the inside circumference of the drain pipe while engaging the ends of the axle or shaft which extends substantially across the diameter of the drain pipe.

Abstract: A filter screen for filtering contaminant particles from the fluid system of a hydraulic system comprises a screen which forms an axially extended convoluted nipple-like enclosure which opens through a passage formed in a base and terminates at a nose portion opposite the base. The screen has folded sides which comprise a plurality of angularly spaced alternating generally convex surface sections and generally concave surface sections generally symmetrical to the central screen axis. The screen is folded to form a continuous serpentine rim configuration at the base. The serpentine rim comprises an inner plurality of angularly spaced fold segments which engage the exterior surface of the base and an outer plurality of angularly spaced fold segments which overlap the inner fold segments in an alternating fashion. The screen is shaped and dimensioned so that the surface area of the screen generally increases from the nose to the base of the screen.

Abstract: A filter apparatus and method is provided wherein a tank is adapted to receive unfiltered liquid. An outlet chamber is located adjacent the bottom wall of the filter tank and is separated therefrom by a perforated plate. A filter media is movable across the rear, bottom and front walls of the filter tank and accordingly, unfiltered liquid must pass through the filter media as well before entering the outlet chamber. A chain flight assembly is provided which is movable across the filter media along the rear, bottom and front walls of the filter tank. As the chain flight assembly is continuous, a return path is across the top of the tank above the unfiltered liquid. A baffle plate is provided near the rear wall within the filter tank.

Abstract: A plastic filter assembly having an upper receiving container and a lower receiving container. Either the top or bottom container is provided with at least two recesses for receiving a locking pin in the container not having recesses. The recess has a first receiving portion and a locking portion. The locking pin has an angled engaging surface inclined with respect to longitudinal axis of the container.

Abstract: An aquarium filtration system includes an assembly of coaxial tubes within an aquarium which draws water through the conventional under-gravel filtration system of the aquarium, and communicates the initially filtered water to a fine-sand filter assembly located in a separate tank below the aquarium. The filtered water in the lower tank is then pumped upwards through the innermost tube of the coaxial tube assembly and returned to the aquarium. A water conduit, which surrounds the water supply tube, extends upwards to the desired water level of the aquarium, and conduit is axially adjustable to vary the water level. A casing surrounding the water conduit has an open bottom and allows water from the under-gravel filtration system to pass upwardly to the top of the water conduit, where it is drained to the filter assembly in the lower tank.

Abstract: A gravity liquid filtration apparatus with increased filtering efficiency includes a frame; a pool-forming assembly mounted in the frame, the pool-forming assembly including two spaced-apart, rotatable containment discs and a discharge element mounted between the two containment discs; a filter medium supply roll; a filter medium carrier assembly for pressing an elongated filter medium supplied by the filter medium supply roll against the peripheries of the two containment discs along corresponding bottom arcs thereof, this filter medium carrier assembly being intermittently operable to move new filter medium against the two rotatable containment discs; and a liquid input element for supplying liquid influent between the two containment discs and downwardly onto a downwardly sloped portion of the filter medium.

Abstract: A diesel fuel filter, which is arranged in a conduit between a fuel tank and a fuel injection pump, comprises a housing accommodating a filter element and a cover non-releasably connected to the housing. A temperature-responsive switching device for switching fuel overflow quantities from the pump to the tank as well as a ventilation device are positioned in a chamber formed by a protruding formation of the cover and a flat plate connected to the housing. A plate shaped pressure control valve, which opens into a contaminated side of the filter element, connects that side to the chamber.

Abstract: A method and apparatus for cleaning cooling tower basins. The apparatus includes a reservoir and large pipe extending from the tower basin to a lower level to act as a siphon. A water supply can fill the large pipe, and a valve can be opened to start the siphon. A cleaning tool remains below the water level in the basin to maintain the siphon while the basin is cleaned. The makeup water valve maintains the desired water level in the basin, so the tower can remain in operation during cleaning. The material removed from the basin is strained and the waste water is disposed of through conventional sewerage.

Abstract: The tubular trash net is a cleaning and collecting device for pre-treatment of sewage, where the water which is to be separated from waste trash materials is led through a collecting net (8), after which the net (8) containing the separated trash is drawn through mechanically-driven rollers (10) which simultaneously de-water the trash prior to its being conveyed, together with the used net (8), to a container for disposal, while runoff pre-treated water is sent on for either further treatment or deep-water outfall.

Abstract: A filtering device has a one-way filter belt guided by an endless screen support belt in the filtration area through at least 120 degrees on an arcuate path for the formation of a deep liquid inlet area. The supply of liquid occurs in the central portion of this arcuate path. Sludge bars coming to rest on the filter belt prevent sludge accumulations in the liquid inlet area.

Abstract: A center valve rotary drum filter includes radially disposed baffles or vanes which extend in the center valve opening from axial surface channels to a central drainage conduit. The baffles provide channels in the center valve opening which collect, direct, and accelerate filtrate flow toward the drainage conduit thereby improving the overall operating efficiency of the filter. The center valve rotary drum filter further includes a curved flow passage between the flow-confining walls. This flow passage is curved toward the central axis of the drainage conduit for directing filtrate flow to the drainage conduit. In a preferred case, the curved flow passage comprises a concavely curved, cone-like member having a broad proximal base and a narrow distal end. The base end is directed toward the one of the radial flow-confining walls opposite the entrance to the drainage conduit, the distal end being directed toward the central axis of the drainage conduit.

Abstract: A cylindrical pressure vessel housing a filter media wherein the vessel is formed from a tubular thermoplastic pipe portion having opposite conical shaped end portions integrally formed with molded internal base portions with one base portion having integrally molded thereto the filter media in sealed position within the vessel housing.

Abstract: A rotatable filter assembly, primarily intended for separation of fibers from a fiber suspension, comprises a number of annular filter discs (3) formed by a plurality of filter elements (5). The filter discs are mounted on a horizontal drum rotatable in a container (1) and formed by axial discharge tubes (6) and transverse tubes (7) which communicate with the individual filter elements (5). A collecting hopper (8) extends into the drum through an open end of it. During at least part of the rotation of the drum, the interior of each filter element (5) is kept at a pressure lower than that prevailing at the outside of it. The filter assembly is characterized in that the axial discharge tubes (6), as seen in a cross-sectional view, are arranged in groups each comprising at least two tubes.

Abstract: A pump (B) pumps water from a swimming pool (A) to a forward/reverse direction control valve (D). The control valve (D) has a first or forward flow state in which it channels water into an inlet (20) of a filter (C) and from a filter outlet (24) back to the swimming pool and a second state in which it channels the water into the fluid outlet (24) and from the fluid inlet to a drain (28). A microprocessor based electronic control circuit (E) selectively actuates the pump at preselected intervals for preselected durations such that the water from the swimming pool is intermittently filtered. The control circuit further monitors the fluid pressure with a low pressure limit switch (46). In response to the pumped fluid pressure failing to achieve a low limit within a preselected duration, the control circuit terminates operation of the pump. Further, the control circuit monitors the water pressure with a high pressure limit switch (48).

Abstract: Solids suspensions are dewatered by filter plate pressing by adding a flocculant downstream of the filter press pump(s), the pump(s) being of the positive displacement type whereby the amount of flocculant required can be determined from the speed of the pump(s). Apparatus is provided which includes a filter plate press, one or more filter press pumps of the positive displacement type, and means for sensing the speed of the pump(s) and for controlling the dose of flocculant in dependence thereon. A mixer is constructed as a cylindrical chamber with radial inlets and axial outlets, and includes plate-like impellers.

Abstract: Pulp sheet take-off apparatus which allows removal of drum valve parts from existing high vacuum rotary drum filters and significantly increases the production capability of existing and newly designed high vacuum rotary drum filters includes an enclosed take-off chamber that is mounted immediately adjacent and parallel to the face of the filter drum on the descending side thereof, the chamber being connected by piping to the filter drum barometric leg or other subatmospheric pressure source as a means of maintaining subatmospheric pressure in the chamber equal to or less than the internal pressure of the filter drum.