Abstract: A novel treatment method for recovering halogenated vacuum pump oils such as chlorotrifluoroethylene, from contaminated filter papers. The process utilizes a trichlorotrifluoroethane (TCTFE) solvent and water mixture to extract the oil followed by vacuum distilling the resulting extractive.

Abstract: In a filter pressure container provided with a plurality of vertically suspended tube-like filter elements having a filter cloth thereon the filtration of residual volumes of a liquid being filtered and the rinsing-out of the filter cakes built up during the filtration on the filter cloth are carried out by pumping out of the residual liquid or the rinsing liquid from the container by pump into an injector mounted in the container above the filter elements. The injector sprays out the residual liquid or the washing liquid over the filter elements while a pressure gas or air is simultaneously supplied into the container to force the liquid mist through the filter elements.

Abstract: A process for recovering hydrocarbon oils and hydrocarbon oils containing dissolved additives from filter cakes produced by filtering such oils using a siliceous filter aid.A small amount of a release agent, up to 2 cc per gram of filter cake, is slowly added to the filter cake with agitation to prevent formation of a release agent phase and then a further quantity of release agent is added to the resultant mixture with gentle stirring and the final mixture is then held quiescent at elevated temperature until an oil phase separates. The oil phase is removed and the remainder of the mixture is filtered to separate a release agent filtrate and a filter cake consisting mainly of filter aid.

Abstract: A solvent recovery method for removing cleaning solvent from dirty, solvent-laden filter cartridges. The cartridges are placed in a low temperature, water vapor environment. Water vapor passing through the cartridges combines with and replaces the solvent in the cartridges and is then condensed into liquid form. The liquid is deposited in a stratum-forming separator. The water is bled-off to form makeup water in the water vapor environment and the solvent is bled-off from the separator in to a receiving tank from which it may be selectively drawn.

Abstract: A filter apparatus has an elongated shaft, a plurality of filtering elements mounted on the shaft and spaced from one another in direction of elongation of the latter, and means for cleaning the filtering elements. The cleaning means includes a source of cleaning medium under elevated pressure and a plurality of nozzle elements communicating with this source. The nozzle elements face toward surfaces of filtering material provided on the filter elements and are turnable relative to these surfaces. The cleaning medium is ejected from the nozzle elements at a pressure between substantially 5 and 100 bar toward the surfaces of the filtering material of the filter elements so that the cleaning medium removes a cake deposited during a filtering process from the surfaces of the filtering material and thereupon also cleans the filtering material of the filter elements.

Abstract: Cleaning a filter surface (16) in situ in a filer housing (10) forming part of a pressure filtering apparatus for liquids is carried out by drying the coating deposited on the filter surface by means of hot air which is caused to flow at a moderate rate through the suspension chamber (5) of the filter housing in a direction over and substantially parallel to the sludge-coated filter surface. The dried coating is detached from the filter surface and removed from the suspension chamber by means of compressed air which alternately with the hot air and at a substantially higher rate than the latter also is caused to flow in a direction over and substantially parallel to the filter surface.

Abstract: A filter press comprises a series of plates and frames separated by filtering sheets into which a liquid to be filtered can be fed via at least two inlet pipes. An outlet pipe is provided to enable filtrate to egress from the press leaving the filtered residue behind in the frames. In order to clean the press, valve means are provided to close off the outlet pipe and to isolate the inlet pipes from each other. A cleaning liquid can then be fed into one of the inlet pipes to pass into the frames and flush out the filtered out residue therefrom via the other inlet pipe.

Abstract: A process is provided for removing suspended solids from a waste water stream exiting from a wet rendering plant, a centrifugal rendering plant and/or a hide curing brine system before the stream enters a public sewer system. Such waste water typically has some oils, fats and/or protein particles in addition to easily settled solids previously removed therefrom. The waste water is delivered to a holding tank wherefrom the waste water is drawn and pH adjusted with sodium carbonate, sodium hydroxide, or the like. Air is injected into the pH adjusted waste water along with flocculating agent such as ferric sulfate. Thereafter, the waste water is injected at a relatively low velocity into a flotation tank wherein flocculated wet solids urged upwardly by the injected air are allowed to float to the top of the tank and water which is relatively low in suspended solids and biological oxygen demand is removed from the lower portion of the tank and is pH adjusted and sent to a sewer.

Abstract: A device for the distribution of water to be treated into and for the recovery of washing liquid from a water treatment filter apparatus of the type including a tank containing therein a filter material includes a channel coupled to and extending along the length of the tank, the channel receiving therein water to be treated. The channel has an opening into the interior of the tank at a level above the filter material. The opening is defined at the lower portion thereof by an overflow over which the water to be treated flows from the channel to the tank. The overflow includes a first inclined plane inclined downwardly and away from the channel in a direction toward the tank and a second inclined plane inclined downwardly and toward the channel from the first inclined plane. The inclined planes extend into the tank and form a deflector structure to prevent any filter material from passing through the opening during backwashing of the filter material.

Abstract: In cleaning plate-type filter elements in a tank filter, the tank is opened and a cleaning tube is placed upwardly around one of the downwardly extending filter elements providing an annular flow space along the length of the element. A seal member is located in the upper end of the cleaning tube to close off the upper end of the annular flow space. Pressurized cleaning fluid is supplied into the lower end of the tube where it flows upwardly through the annular space and then into the filter element to dislodge any contamination. The material displaced continues its flow through the filter element in the same direction as is taken by the fluid being filtered.

Abstract: A process for regeneration of a filter medium is provided according to which the filter medium is treated with a liquid which breaks down deposited organic materials on the filter medium. The preferred liquid for regeneration of the filter medium is concentrated sulphuric acid.

Abstract: A filter apparatus has an elongated shaft, a plurality of filtering elements mounted on the shaft and spaced from one another in direction of elongation of the latter, and means for cleaning the filtering elements. The cleaning means includes a source of cleaning medium under elevated pressure and a plurality of nozzle elements communicating with this source. The nozzle elements face toward surfaces of filtering material provided on the filter elements and are turnable relative to these surfaces. The cleaning medium is ejected from the nozzle elements at a pressure between substantially 5 and 100 bar toward the surfaces of the filtering material of the filter elements so that the cleaning medium removes a cake deposited during a filtering process from the surfaces of the filtering material and thereupon also cleans the filtering material of the filter elements.