Abstract: An apparatus for dewatering and squeezing a water containing material comprises a drum with a sieve mantle defining two co-operating drum sections, each comprising a feed screw extending therein. The first section of the drum in the feed direction is formed for dewatering of the material mainly by self-drainage. The first drum section is rotatable and is provided with means for cleaning the sieve mantle holes. The second section is formed for increased compression of the material, and has a thread height for the feed screw smaller at the outlet of the second section than at the inlet to this section.

Abstract: Method and drum filter for thickening of slurry and for treatment of the slurry with liquid. The slurry to be thickened is passed onto the filter face of a drum (3) revolving in a basin (3), and the treatment liquid is passed through the pulp web formed on the drum. The consistency of the pulp web is increased by pressing a compression plate (10) against the pulp web. The compression force of the compression plate (10) is produced by means of the pressure of a liquid and/or gas passed to the convex side of the plate. The compression force can be adjusted by adjusting the pressure prevailing in the gas space outside the drum (3).

Abstract: A decker comprises a tank having a thickening drum mounted rotatably therein and including a filtering shell. The inside of the drum communicates with an inlet for feeding mass, whose consistency is to be increased during the thickening process and outlets for discharging the thickened mass after the thickening process. The filtrate separated from the mass being thickened, is arranged in a flow communication from the inside of the thickening drum through the filtering shell of the drum to the bottom portion of the tank. At least one separating member is placed in the bottom portion of the tank outside the drum and forms a partition point or partition line situated transversely with regard to the direction of rotation of the drum and at a predetermined, angular distance from the horizontal plane coinciding with the axis of rotation.

Abstract: A method for application in conjunction primarily with so-called rotating filters of the kind which include a substantially cylindrical filter tube (1) which is provided with a permeable wall and which is sealingly journalled at preferably two axially spaced locations, preferably at the ends of the tube, and which is arranged for rotation about its longitudinal axis in a filter jacket (2), wherewith material to be filtered, the so-called feed, is supplied to a space or chamber (11) located between the filter jacket and the filter tube, and the filtered substance, the filtrate, being tapped-off from the interior of the filter tube.The method is particularly characterized by sealing and journalling the filter tube (1) in a manner adapted to substantial changes in temperature in the filter tube and that facilities are provided for sterilizing the filter.

Abstract: A process is disclosed for recovering a cellulose ether from a cellulose ether suspension in which the cellulose ether is recovered as a filter cake from a pressure filtration, particularly using a rotary pressure filter. Clogging of the separation or filtration device is avoided, providing for a long useful life. A multi-layer wire mesh filter medium is employed, formed of mesh layers of different wire thicknesses and/or mesh size. After removal of the filter cake, the filter medium is cleaned with steam, compressed air or pressurized water.

Abstract: A method is provided for the reduction of the level of dimethyl polysilioxane remaining in a silicone rubber product containing said dimethyl polysiloxane to an ultra-micro level, comprising the steps of immersing the silicone rubber product in an organic solvent for the dimethyl polysiloxane and subjecting the immersed product to ultrasonic vibrations in the organic solvent.

Abstract: In a causticizing process for separating at least white liquor and lime sludge out of the process, filters in the form of discs or drums are arranged. The filtrations take place under positive pressure and the filters are arranged in a closed system. Such a pressure filter can also be arranged for the separation of sludge.

Abstract: A method of and apparatus for separating knots from a fibre suspension in the wood processing industry. A known problem in the prior art has been the quick wear of the screen surface of the knotter when the screen surface has been profiled. On the other hand the ability to separate with an unprofiled screen has not been satisfactory. When using a profiled screen cylinder (5), it has been noticed in performed tests that it is preferable to feed the pulp from the connections (2) in the direction of rotation of the screen cylinder and also to discharge the reject from connections (4) and the accept from the connections (3) in the direction of rotation of the cylinder (5). Accordingly, there is not only less wear of the screen surface, but also a significantly smaller consumption of power per pulp ton than in the prior art apparatuses.

Abstract: Filter apparatus and method for separating contaminants from a liquid stream through at least a partially submerged liquid pervious rotatable drum under negative pressure and having a flexible filtering web fed therearound with that portion of the drum not contacted by the filtering web being covered by a cover means with the filtering web being guided to enter and exit the liquid stream to contact the pervious rotatable drum at preselected angles to make optimum contact with the rotatable drum.

Abstract: An improved method and apparatus for filtration includes an outer stationary body, an inner rotating body defining a gap with the outer body for receiving a fluid sample, the surface of one of the bodies defining the gap being a filter. The rotation of the inner body creates Taylor vortices which continuously displace occluded solute on the filter surface. The filter can be a membrane. The rotational speed and/or a driving force across the membrane may be varied to control the composition of the permeate.

Abstract: An improved method and apparatus for filtration includes an outer stationary body, an inner rotating body defining a gap with the outer body for receiving a fluid sample, the surface of one of the bodies defining the gap being a filter. The rotation of the inner body creates Taylor vortices which continuously displace occluded solute on the filter surface. The filter can be a membrane. In one embodiment the device may be used to filter very small volumes of fluid such as are handled in clinical and other laboratories.

Abstract: The invention relates to an apparatus for separating the flowable constituents from a mixture of flowable and non-flowable constituents particularly for the preparation of foodstuffs, the apparatus includes a driven perforated drum having a perforated circumferential surface, a pressure belt enclosing part of the circumference thereof and pressable onto the same by at least one pressure roller, as well as a supply mechanism for supplying the product to be treated into an entry wedge formed between the perforated drum and the pressure belt.

Abstract: In a filtration apparatus in which a flocculant is added to promote flocculation, efficient use of the flocculant is ensured by measuring an operational parameter of the apparatus dependent on the degree of flocculation, and adjusting the amount of flocculant being added to the minimum that causes maximum flocculation. As the operational parameter, measurement can be made of the depth of a pool of the material at the lower end of an upwardly inclined filter belt, or of the resistance to movement of a part of the apparatus e.g. the torque required to rotate a filter drum.

Abstract: The improved rotary vacuum filter discharge flow assembly provides a discharge filtrate stream having a substantially increased filtrate flow velocity, a reduced vacuum loss, a reduced level of turbulence and air entrainment to means defining an axially-extending valve-receiving space in communication with a remote filtrate collection area. The subject assembly, which is located at one end of a rotary vacuum filter, includes a plurality of radially-disposed, inlet conduit means connected to and in communication with the rotary vacuum filter discharge flow assembly and comprises a plurality of radially-disposed discharge conduit means for transporting the discharge filtrate stream from the inlet conduit means to the valve-receiving space means. Each of the discharge conduit means are connected at one end to one end of the inlet conduit means, and are joined at the other end to respective adjacent discharge conduit means for defining the valve-receiving space means.

Abstract: A continuous contacting device is disclosed wherein a fluid stream may be contacted with particulate exchange materials. The device includes a plurality of rotating chambers filled with particulate material. Fluid is supplied individually to these chambers through a plurality feed ports which are in periodic fluid communicating relation with each of the chambers. A plurality of fixed discharge ports which are likewise in periodic fluid communicating relation with each of the chambers is also provided. A process for continuously contacting fluids with the solid particulates is also disclosed.

Abstract: The novel sealing means of this invention generally comprises a replaceable, annular-shaped sealing device having a substantially L-shaped radial cross-sectional configuration for effecting the indirect fluid-tight sealing of an entry passageway formed at the entrance to either of the channel means. The L-shaped radial cross section of the sealing device comprises an axially-extending base section capable of extending within and effectively sealing off, in a fluid-tight manner, either of the entry passageways. The sealing device also includes a radially-extending leg section capable of facilitating the effective sealing of either of the entry passageways and for maintaining the sealing device in a substantially fixed position within the entry passageway means by the securing engagement of the inner radial surface of the leg section with the outer end of either of the respective trunnion and the inner vat insert element.

Abstract: An improved method and apparatus for filtration includes an outer stationary body, an inner rotating body defining a gap with the outer body for receiving a fluid sample, the surface of one of the bodies defining the gap being a filter. The rotation of the inner body creates Taylor vortices which continuously displace occluded solute on the filter surface. The filter can be a membrane.

Abstract: A centrifugal finisher and method of its operation are disclosed for separating finished juice from an initial juice including substantial solids or for separating finished fluid from any slurry including substantial solids, the slurry being introduced into one end of a cylindrical screen driven in rotation for centrifugally urging the slurry against the screen and causing a fluid component to pass through the screen. Wiper paddles are arranged on a support drum for rotation in wiping contact with the screen and for limited movement relative to the screen for continuously moving solid material from the slurry toward an outlet axial end of the screen.

Abstract: The present invention provides significant improvements in the design and performance of a specific type of Rotary Membrane Filter (RMF) apparatus which has the capability of separating particles from a fluid having the same and nearly the same density as the particles by utilizing shear to achieve separation, not centrifugal forces. A particular application for the apparatus is in the processing of fluid suspensions in which the suspensions contain fragile particles which are subject to damage due to excessive shear stresses. The prior art describes processing at constant shear rate, whereas the present invention provides the design and optimization of operation of such an apparatus at constant shear stress, which is maintained at a value below that at which significant damage to the fragile particles is encountered.

Abstract: Drill cuttings, and similar slurries or mixtures oily solid particles, are treated by a dryer apparatus which vaporizes the liquid and discharges relatively large solid particles for disposal. Vapor and entrained solid fines are conveyed from the dryer to a condenser and then to a rotary drum vacuum filter having a precoated filter media disposed thereon. The solid fines are filtered by the filter media comprising diatomaceous earth or perlite and the clarified condensed liquid is conveyed to separator means for separating oil, water and any other liquids present. The filter media stripped from the filter and contaminated with entrapped solid fines is conveyed through the dryer means and disposed with the solids particles being discharged from the dryer.

Abstract: A method and apparatus for thickening a pulp, in particular a pulp containing fibres. The pulp is thickened hydraulically while it flows through a space between two screen surfaces. Thickening on alternate screen surfaces is prevented for cleaning by closing the valves in the outlets. Pulp is removed from the screen surfaces by vanes.

Abstract: The present invention provides a rotary drum filter wherein one or preferably two rotary drum filters are submerged in a tank of liquid to be filtered. Each rotary drum filter is comprised of a generally cylindrical tank having a perforated outer wall plate over which is applied a cloth type filter media. A suction pipe is included inside the rotary drum filter so that filtered liquid can be drawn into the rotary drum filter through the pressure differential established by the suction pipe. Clean filtered liquid exits the suction pipe to the industrial apparatus with which the filter apparatus is used. A backwash vacuum box extending generally the length of the rotary drum filter media is in contact with a portion of the rotary drum filter media. A partial vacuum is established in the vacuum box such that filtered liquid can be drawn outwardly from the rotary drum filter such that solids accumulated on the filter media are drawn off from the filter media thereby cleaning that section of the filter media.

Abstract: In a procedure for filtering lime sludge meant to be regenerated to lime. Lime sludge is produced in the causticizing process in a sulphate cellulose mill, where it can be reused after regeneration to lime. In the procedure, lime sludge suspension is filtered on a filter drum in continuous rotation by depositing lime sludge on the drum and detaching part of the superficial layer of the lime sludge on the drum with a scraper so that the deeper lime sludge layer on the drum, which by-passes the scraper, serves as filtering medium for the superficial layer that is detached (as a so-called pre-coat).

Abstract: Filter units for use in filtering liquid suspensions of material prone to form a filter cake resistant to continued flow of filtrate therethrough, e.g., wastewater treatment sludge, have a pair of planar sides arranged in a V-shape. Such sides are formed of rigid filter media, e.g., porous sheets of granular material bound in a resin matrix. Suspension to be filtered is charged into the trough and filtrate is drawn by vacuum through its porous sides. A plurality of such units are arranged side-by-side about a common center in a cylindrical assembly which can be rotated about such center at a predetermined rate to permit each unit to pass through a series of filtering steps to provide new filtering methods.

Abstract: A shower pipe for a rotary drum filter has a square cross-sectional shape defined by top, bottom and side walls. The sidewalls and a pair of lengthwise-extending continuous diffusion flanges depending from the bottom wall of the pipe stiffen the pipe against sag for placement at a 12 o'clock position spanning the filter drum. The pipe is formed of fiberglass reinforced plastic in two longitudinally-divided hollow sections in a pair of mirror image, trough-like molds. Each section has a pair of interconnection flanges for mating the sections together. The interconnection flanges extend normally to the sidewalls to stiffen the pipe when the bottom wall of the pipe is vertically-oriented for placing the pipe at a 9 o'clock position along one side of the filter durm. Glass rods are secured in the interior corners of the pipe to provide diagonal rigidity, for placing the pipe at, e.g., 10-11 o'clock position between the top and side of the filter drum.

Abstract: Disclosed is an improved rotary drum vacuum filter that is especially useful in the filtration of particulates that form an easily eroded cake. The improved filter utilizes sprayers and a spray blocking means to achieve an unexpectedly efficient rinse of the cake.

Abstract: A method for dewatering suspensions, in particular communal sewage sludges, in an apparatus comprising a cylindrical filter drum which can be rotated about an axis, a discharge outlet at the opposite end from a feeding inlet and, if desired, in its interior baffles, for example, ring-shaped wier-like obstructions. A conical filter drum which tapers towards the outlet end is fitted to the cylindrical filter drum forming an outlet part. The axis of the drum assembly can be inclined such that the lower contour of the conical outlet part is horizontal or at an acute angle of up to 15.degree. above and/or below the horizontal.

Abstract: A method and apparatus for producing a concentrated extract from an ice crystal-fluid solution by suction separation of the ice crystal solvent. A multiple compartment drum is rotatably mounted within a tank containing the solution, a filter medium covering the compartments. A vacuum source selectively creates a suction in the compartments to draw the solution through the filter medium, the ice crystals remaining on the filter medium and the fluid passing into the compartments. The ice crystals are scraped from the filter medium and the fluid is recycled for further processing.

Abstract: Solids or insoluble liquids are removed from a liquid body by a partially immersed collector wheel which rotates about a horizontal axis and comprises a mesh sheet bent into a spiral shape. The sheet is formed of expanded metal to create contaminant-free turbulent zones adjacent to the sheet during rotation of the wheel. A receptacle with an upper opening is located within the collector wheel, in a position where it will receive the contaminants carried thereto by the trailing portion of the spiral mesh sheet. A screw in the receptacle discharges the contaminants to a discharge tube.

Abstract: A separation device designed to effect substantially continuous separation and/or fractionation operations as in, for example, ion exchange or other solid-fluid contacting systems. Also disclosed and claimed is a method for effecting such continuous treatment of plural fluid streams. The device is characterized by its construction to permit treatment of plural streams simultaneously and continuously. Fixed inlet and outlet nipples are provided for introducing and removing the fluid streams, and the inlet and outlet nipples are operatively interconnected by a rotating member which is internally divided into a plurality of working sections. By virtue of the rotatable construction of that member and its plural working sections, discrete fluid streams may be treated separately, yet simultaneously. Furthermore, the device of this invention is such that fluid flow in either of two directions may take place through each of the working sections dependent only upon predetermined process parameters.

Abstract: Thickening of paper pulp, or a like suspension, is effected prior to feeding the pulp to an apparatus utilizing stationary screens for effecting washing, bleaching, or further thickening of the pulp. The stationary screens are mounted in a top portion of a vertical-axis vessel, and a plurality of radially extending rotating hollow arms, with annular screens mounted on them, is provided in the bottom of the vessel to effect thickening of the suspension from, for example, 11/2% consistency to about 9-14% consistency. Extraction from the hollow arms is provided through conduits extending vertically through a hollow shaft for rotating the arms, and a filtrate valve is also mounted within the hollow shaft in operative communication with the filtrate conduits, and includes a valve member which is rotatable in a different direction, and at a different speed, than the hollow shaft.

Abstract: A method and device for filtering a suspension (14), for example of yeast or other plant cell material, on a rotary vacuum filter (10), beneath which a trough (4) containing the suspension (14) is located. In order to improve the balance between dipping zone and drying zone, according to the invention a take-off knife (1) for taking off the filter cake (8) resulting from the filtering is attached to the trough (4). The level of the suspension (14) is maintained constant, and the trough (4) is moved by means of a feeding device (7) to the center of the drum (12) of the vacuum filter (10) while the drum is rotating.

Abstract: A method and apparatus are disclosed for extracting finished juice from an initial juice including substantial solids or for extracting fluid, preferably finished to a high degree, from any slurry including substantial solids, wherein the slurry is introduced into one end of a cylindrical screen, the cylindrical screen being driven in rotation for centrifugally urging the slurry against the screen and causing fluid from the slurry to pass through the screen.

Abstract: This invention provides a non-fibrous combustible filter aid for vacuum pre-coat filter units which is effective to maintain a filter bed coating on rotary filter drums just sufficiently porous to pass the liquid of a slurry while retaining the slurry solids thereon and is capable of being scraped off the bed in thin film form with the slurry solids thereon. The filter aid comprises relatively non-compressible non-fibrous granular charcoal or nut shell particles having a dry bulk density from about 0.3 to about 0.6 grams per cubic centimeter, a particle density of about 1.4 to 1.7 grams per cubic centimeter and a particle size range of 30 to 125 microns. The filter aid of this invention is capable of being burned with the solids deposited thereon to recover the heat value thereof or to dispose of the solids, is free from silicates or other non-combustible ingredients, and is devoid of fibers which will interfere with the proper operation of the filter unit.

Abstract: A fluid assisted doffer (30) is disclosed in combination with a fluid filter (10). The fluid filter (10) includes a rotatably mounted drum (23) covered with a filter screen (25). Fluid is filtered through screen (25) from the upstream to the downstream side to form an overlying porous layer of particulate matter. The downstream side of the drum (23) includes filter chambers (A) and (B) being sealed against direct fluid flow. The fluid assisted doffer comprises a doffing chamber (45) positioned on the downstream side of screen (25) at the position where the overlying porous layer of particulate matter is to be removed from the screen (25) and communicating through the screen (25) with the upstream side thereof. The doffing chamber (45) is sealed against direct fluid communication with filter chambers (A) and (B) on the downstream side of the screen (25).

Abstract: To separate a small alga such as Dunaliella from a containing liquid, a filter substrate is provided with a surface coat including a large alga such as Spirulina. The Dunaliella and some liquid are run through the Spirulina and the substrate and so are separated with some Spirulina content.

Abstract: A process for dewatering sewage sludges, the dewatering characteristics of which have been improved by adding an organic flocculant, on a chamber filter press, wherein the greater part of the water in the flocculated sludges is removed by gravity filtration in a process step upstream of the chamber filter press, without application of a pressure difference, and the actual pressure filtration, on the chamber filter press, is only then carried out.In principle, commercial products can be used as the organic flocculant. These are water-soluble, macromolecular compounds which have been obtained by polymerization or copolymerization of acrylamide, acrylic cid and/or their salts, or of esters of acrylic acid or methacrylic acid with specifically modified alcohol components.

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: A process of dewatering sludge in which raw sludge and a flocculating agent are first mixed by suitable means, then fed into a rotary filter drum or similar device to effect thickening of the sludge and partial dewatering thereof. The now thickened sludge is then conveyed through a filtering assembly in which the sludge is subjected to further dewatering forces, which could be vacuum, centrifugal, static pressure, or pressure while moving along the filter surfaces, thereby further dewatering the sludge. The filtrate discharged from the filter drum and the filtering assembly and also wash water used for cleaning the filter surfaces in the filter drum and the filtering assembly are at least partly returned to the filter drum to effect total flocculation and recapture of sludge particles contained in the filtrate and the wash waters.

Abstract: Disclosed is method and apparatus including a tank in which shredded corrugate is immersed and shuffled in a solvent fluid capable of attacking and weakening the adhesive bonding the core ply from the liner plies; said corrugate being advanced from its entry point into the tank to an exit point therefrom at a timed rate to limit its absorption of the solvent fluid prior to its transfer to delaminating apparatus.

Abstract: A method and equipment for thickening various suspensions, such as, e.g., pulp slurry, waste waters, or mineral sediments. The sludge or slurry is passed into a basin in which a filter unit rotates as partly submerged in the sludge or slurry. The thickened sludge or pulp web is gathered onto the surface of the filter unit from the sludge or the slurry in the basin. The sludge or slurry is passed from the basin to above the sludge or slurry level. In order to pre-thicken the sludge or slurry, part of the liquid contained therein is removed through a wall located between the feeding-in point of the sludge or slurry and the surface level of the sludge or slurry.

Abstract: The present invention utilizes a closed-type vessel comprising a filtering chamber, at least one perforated filter cylinder a portion of which is positioned within the filtering chamber, said filter cylinder being rotatable at any desired speed and having a filtering surface covered with a filter cloth, and a squeezing roll and sealing roll which engage with said filter cylinder through the filter cloth at all times to define a sealing and operating wall. Any sewage to be treated is supplied under pressure to the filtering chamber and filtered through the filter cloth at the filtering surface of the filter cylinder. Filter cake deposited on the filter cloth is continuously transferred to the outer periphery of the squeeze roll and then separated therefrom outside the filtering chamber by any suitable means such as a scraper.

Abstract: An oil recovery apparatus and method, particularly for removing oil and grease from the discharge of dishwashing machines or the like, provides a small size assembly employing the same principle as in U.S. Pat. No. 4,051,024. This apparatus and method employs single rotating discs of plastic or plastic coated material and each disk has a pair of scraper blades arranged to scrape opposite sides of the rotating blade. Exterior of the container for the oil recovery apparatus is at least one filter basket adapted to receive the flow into the strainer container of large particles of food and other waste such as cigarette butts and the like. Each filter is disposed for the ready cleaning of accumulated matter from the basket. There is shown plural filters, valve controlls, auxiliary heating and disc support means to be more fully described.

Abstract: The method of treating sewer scum including combustibles and debris includes the steps of collecting the scum from sewage, delivering it to a perforated filter drum, continuously rotating the drum upon an inclined longitudinal axis, applying heated air under pressure to the exterior of the drum along its length inwardly of the perforations, discharging the debris continuously and collecting the filtered combustibles. Apparatus for filtering said scum includes an elongated cylindrical perforated drum rotatable on an inclined axis receiving scum at its upper end and discharging debris at its lower end. A cylindrical shell sealingly encloses the perforated portion of the drum for providing a pressure chamber above the drum and a collection chamber below the drum. An elongated air channel along the interior of the shell delivers high pressure heated air to said pressure chamber and filtered scum accumulates in the collection chamber.