Abstract:
The invention relates to a method for cleaning the filter medium in a suction dryer by means of ultrasound in an essentially continuous operation. According to the invention, the ultrasonic beams emitted from at least one ultrasonic oscillator (1, 12, 22, 36) are focused essentially near to the filter surface (4, 14, 25) of the filter medium, advantageously on the filter surface (4, 14, 25) of the filter medium, in order to create at least one ultrasound focusing zone.
Abstract:
Filter apparatus for filtering contaminants from a fluid, such as machine tool coolant, are disclosed. One filter apparatus includes a filter drum unit having a generally cylindrical open perforated support sheet with a cylindrical screen element mounted thereabout. Circumference varying mechanisms, such as turnbuckles, are connected relative to the support plate to vary the circumference of the support plate and the tautness of the screen element. A disc filter assembly having a mandrel and fluidly attached annular disc filter elements is also described. Each annular disc filter element has an inner structure with concentric ribs forming concentric grooves therebetween which are connected to radially extending grooves. A screen element is supported by the ribs so that the microscreen will not tear while allowing filtering of fluid into the grooves which are in fluid communication with the mandrel. A disc filter assembly having a mandrel in fluid communication with a plurality of rectangular disc filter elements is also described. Each disc filter element has a rectangular inner structure which is pleated or folded in an accordion-like fashion. A retainer secures screen elements about the inner structure to prevent contaminants from passing therebetween.
Abstract:
A pressure sorter for fiber suspensions, and a process for the preparation of fiber suspensions, are disclosed wherein a rotor is disposed concentrically within a cylindrical screen that has spaced circumferential rows of narrow through slots through which a portion of the fiber suspension fed into the screen passes radially outward to an accepts chamber external to the screen. The fraction of the suspension which does not pass through the screening slots passes axially out of the screen cylinder as a "rejects" flow. V-shaped grooves around the inflow ends of the screening slots create turbulences in the adjacent suspension material. The rotor includes external profiled elements which generate positive and negative pressure pulses at the adjacent inflow side of the screen as the rotor is rotated. Each profiled element has a front flank approximately parallel to the screen axis and a trailing flank which slopes radially inward of the screen, whereby the front flanks create pressure pulses in the fiber suspension adjacent the inflow ends of the screening slots and the trailing flanks cause suspension to be drawn back through the screen slots. To reduce the risks of cracking of the screen, the number and configuration of the profiled elements, the thickness of the screen, and the flow rates of the suspension through the pressure sorter are correlated such that throughput rates of the fiber suspension do not exceedV.sub.Gmax =32.times.F.sub.f .times.D/8, orV.sub.Smax =50.times.F.sub.f .times.D/8where V.sub.Gmax is the rate of draw-off of the accepts portion in liters/min, V.sub.Smax is the total suspension supplied into the sorter in liters/min, F.sub.f is the sum of the projected area of the front flank sections located opposite the slot rows (in cm.sup.2), D is the screen wall thickness in mm and 8 is a reference value in mm.
Abstract:
The invention relates to a process for the separation, in particular filtration of liquids and solids from solid-liquid mixtures, such as from a mineral, ore, coal or sludge suspensions of contaminated earth. The processing space of the filtration apparatus is submitted to overpressure and includes a collector container for solid-liquid mixture, a pressure filter, a discharge system and container for condensate and solid matter. The separation or filtration takes place at an overpressure and at an elevated temperature, preferably 40.degree. C. to 300.degree. C., conveniently 60.degree. C. to 200.degree. C., preferably about 150.degree. C. The pressure filter device communicates with a source for a heated medium.
Abstract:
A filter apparatus for synthetic plastics material melts containing impurities comprises a housing (1) in which a cylindrical or conical filter element (3) is bearingly supported for rotation around its longitudinal axis (4) by a drive means (8). The outer periphery (15) of the filter element (3) is engaged by a scraper element (20) which surrounds the filter element (3) along a helix line or a spiral line. The material to be filtered is supplied from the outside through an inlet opening (12) to the filter element (3). The filtered material penetrates openings (18) of the filter element (3) and flows into a central hollow space (17) thereof wherefrom it is carried off through a discharge opening (18). The impurities cannot pass the opening (16), gather on the outer periphery (15) of the filter element (3) and are carried by the stillstanding scraper element (20) towards an exit (24). Thereby a reliable construction is achieved which requires less effort (FIG. 1).
Abstract:
A continuous filtration device comprising a cylindrical filter rotationally driven around the axis thereof, a filtration tank in which an outer chamber having an inlet for a liquid to be cleaned and an inner chamber having an exit for a liquid filtrate are separated by the filter, a cleaning means disposed in the outer chamber for spraying a cleaning liquid at high pressure at an acute angle to a surface of a filter to be cleaned, and a guide plate disposed at a position on the side opposite to the cleaning means with respect to the surface to be cleaned for guiding obstacles removed by cleaning and detaching them from the filter. The filter can be automatically cleaned by spraying a liquid to be filtered, liquid filtrate or similar other liquid to the surface of the contaminated filter. The device is useful, for example, for filtration of marine fuel oils or lubricants.
Abstract:
The invention concerns a drum washer. The washer has two plates (14; 18) located after each other in parallel with the drum, and the pulp to be washed is conducted between these plates. Between the plates there is a gap (22) closed by a flap valve (25) by way of which gap washing liquid is conducted through the mat. The washer is especially suitable for washing cellulose pulp.
Abstract:
A filter apparatus for filtering machine tool coolant is disclosed as including a drum filter or a disc filter assembly including a hollow rotatable mandrel mounting a drum filter assembly or plurality of removable hollow disc filter elements each element having a foraminous non-reticulated metal screen having minute openings and a smooth planar surface for providing improved scrape cleanability and preventing movement of machining chips, particulate and also elongate contaminants from one side of the filter to the other side thereof.
Abstract:
A continuous, self-cleaning strainer and method of straining comprising a housing, a rotatably driven shaft mounted on the housing, a primary and a secondary drum concentrically mounted on the shaft and rotatable therewith, the drums having a number of perforations and strainer inserts mounted in each of the perforations, each drum being provided with a reduced pressure backwash zone outside the drum and connected to backwash outlet connected to atmospheric pressure whereby, when a strainer insert passes the reduced pressure zone, pressurized liquid inside the drum forces liquid backwardly through the insert to flush accumulated solids therefrom. Backwashing operation can be commenced by means of a valve disposed in the backwash outlet lines and actuated by a timer or by a pressure differential switch, or both.
Abstract:
Displacement washing of slurry body is provided in a centrifuge filter (peeler centrifuge) by introducing wash liquid along the inner surface of the drum while the drum is rotating. The wash liquid moves through the filter into the slurry body in a broad front to displace the mother liquor of the slurry body toward the axis of rotation of the drum. The mother liquor is removed by an overflow pipe or dip tube to a point outside the centrifuge filter for disposal.