Abstract: A compact cyclone filter train for the removal of hazardous and radiologi particles from a gaseous fluid medium which permits a small cyclone separator to be used in a very small space envelope due to the arrangement of the filter housing adjacent to the separator with the cyclone separator and the filters mounted on a plate. The entire unit will have a hoist connection at the center of gravity so that the entire unit including the separator, the filters, and the base can be lifted and repositioned as desired.

Abstract: A method of manufacturing a water barrier fabric, in flexible or rigid form, and articles manufactured thereby, formed by dispersing a water-absorbent material, in powdered or granular form, among a mass of fibers during the formation of a loose mat of said fibers, to homogeneously disperse the powdered or granular water-absorbent material above, below and on each side of the fibers forming the mat, and thereafter densifying and structurally consolidating the mat, to secure the fibers in position surrounding and entrapping the water-absorbent material, such as by sewing, quilting, needle punching or otherwise bonding the fibers into a consolidated, structurally secure fabric at least partially filled with the powdered or granular water-absorbent material. In a preferred embodiment, one, or both, major surfaces of the fabric is coated with a water-insoluble adhesive to substantially increase the tensile strength of the fabric and to prevent shifting of fibers when installed on sloping surfaces.

Abstract: A multi-layer article of manufacture includes an intermediate layer of a water-swellable colloidal clay, such as bentonite, sandwiched between two layers of flexible sheet or fabric material wherein the two flexible layers of sheet or fabric material are structurally interconnected through the intermediate clay layer, such as by needle punching, after lubrication of the clay with a liquid, such as water, to interconnect fibers of one fabric layer to the other fabric layer at spaced locations over essentially the entire inner surface areas of both sheet or fabric material layers.

Abstract: A multi-layer article of manufacture includes an intermediate layer of a water-swellable colloidal clay, such as bentonite, sandwiched between two layers of flexible sheet or fabric material wherein the two flexible layers of sheet or fabric material are structurally interconnected through the intermediate clay layer, such as by needle punching, after lubrication of the clay surface with a liquid, such as water, to interconnect fibers of one fabric layer to the other fabric layer at spaced locations over essentially the entire inner surface areas of both sheet or fabric material layers. In a preferred embodiment, a water-insoluble adhesive is applied to at least one of the fabric layers to lock the interconnecting fibers in place and substantially increase the structural integrity, particularly the shear strength, of the article.

Abstract: A physical compact vacuum pickup device of critically safe volume and geometric shape is provided for use in radioactive enclosures, such as a small glove box, to facilitate manual cleanup of either wet or dry radioactive material. The device is constructed and arranged so as to remain safe when filled to capacity with plutonium-239 oxide. Two fine mesh filter bags are supported on the exterior of a rigid fine mesh stainless steel cup. This assembly is sealed within, and spaced from, the interior walls of a stainless steel canister. An air inlet communicates with the interior of the canister. A modified conventional vacuum head is physically connected to, and associated with, the interior of the mesh cup. The volume of the canister, as defined by the space between the mesh cup and the interior walls of the canister, forms a critically safe volume and geometric shape for dry radioactive particles that are gathered within the canister.

Abstract: A method of manufacturing a water barrier fabric, in flexible or rigid form, and article manufactured thereby, formed by dispersing a water-absorbent material, in powdered or granular form, among a mass of fibers during the formation of a loose mat of said fibers, to homogeneously disperse the powdered or granular water-absorbent material above, below and on each side of the fibers forming the mat, and thereafter densifying and structurally consolidating the mat, to secure the fibers in position surrounding and entrapping the water-absorbent material, such as by sewing, quilting, needle punching or otherwise bonding the fibers into a consolidated, structurally secure fabric at least partially filled with the powdered or granular water-absorbent material.

Abstract: A method for pressure relief of a containment of a nuclear power plant includes heating a washing fluid in a filter disposed inside a containment at a rated heating power through a thermal bridge, with a gas-steam mixture filling the containment, prior to initial operation of the filter. The thermal bridge is rendered substantially ineffective in an operating state of the filter, leaving the washing fluid with a continuous rated heating power being negligible in terms of filtration. In a nuclear power plant having a containment, a system for pressure relief of the containment includes a filter being disposed inside the containment and having a container. At least part of the container has two walls defining a chamber between the walls. A heat-conducting fluid at least partly fills the chamber during a heating period and is at least half evaporated after attainment of an operating temperature.

Abstract: A waste disposal site, such as an ultimate disposal site for radioactive substances, includes installed waste having hollow spaces remaining therebetween. Packing material fills the remaining spaces. At least one substance to which gaseous toxic substances such as radioactive gases adhere, is admixed with the packing material.

Abstract: A ceramic filter for a dust-containing gas, which comprises a filter base having an average pore size of from 20 to 100 .mu.m, and a filter layer having an average pore size of from 0.2 to 10 .mu.m fixed at least to the filtering side surface of the filter base so that the filter layer fills the pores open on the surface of the filter base.

Abstract: A sorption column for waste-gas cleaning having at least one vat containing a solid stationary sorbent and connected with a lower gas connecting piece and an upper gas connecting piece. The lower gas connecting piece has a coupling member. The vat adapted to be placed on the lower gas connecting piece as a valve in its cover and a valve in its bottom. The upper gas connecting piece has a coupling member. The coupling member of the lower gas connecting piece is adapted to be joined with the valve in the vat bottom and the valve in the vat cover. The valve in the vat bottom and the valve in the vat cover open when joined with the coupling member of the lower gas connecting piece so as to form a gas space communicating from the lower gas connecting piece to the upper gas connecting piece.

Abstract: The invention concerns a filter system having a plurality of individual removable filter units disposed between inlet and outlet ducts for a gas flow path to filter the gas flow. The system comprises one or more filter ports between the inlet duct (3,5) and the outlet duct (4,6) to receive removable filter units (1), a transfer port (25) co-operable with and sealable by a flask (20) for the filter units, a seal plate (14) removably located in the transfer port, means (15) for removing the seal plate, a carriage (18) movable between the transfer port and the filter port or ports, means (15) for placing filter units on or removing filter units from the carriage adjacent to the transfer port and means (8) for placing filter units on or removing filter units from the carriage adjacent to the filter port or ports. The system may be used to filter from a gas flow harmful or potentially harmful substances, e.g. particles which are radioactive, toxic or biologically active.

Abstract: A filtering cartridge, without asbestos, for the filtration of gases, especially hot and/or radio-active and/or corrosive gases. The cartridge comprises a substantially cylindrical, hollow body, closed at one of its ends and open at the other end, containing at least 50% by weight of alumina and/or zirconia. The body is obtained by molding in vacuo of a slip consisting essentially of fibers of alumina and/or zirconia having a diameter less than 20 .mu.m and length less than 25 mm, colloidal silica, at least one organic binding agent, at least one deflocculant, optionally, other fibers, and optionally sodium, drying the slip and heat treating the dried slip at a temperature sufficient to volatilize the organic binding agent and deflocculant.

Abstract: A ceramic filter for a dust-containing gas, which comprises a filter base having an average pore size of from 10 to 100 .mu.m, with the pore size ratio at positions of 75 vol % and 25 vol % of the accumulated pore size distribution being at least 1.3, and a filter layer having an average pore size of from 0.2 to 10 .mu.m fixed at least to the filtering side surface of the filter base so that the filter layer fills the pores open on the surface of the filter base.

Abstract: A nuclear power plant includes a containment for containing activity carriers. An outlet in the form of an excess pressure safety device leads out of the containment. A filter connects the outlet to the atmosphere. The filter includes a container, a washing fluid disposed in the container, a Venturi scrubber being integrated in the container and connected to the outlet, the container having an upper region with a gas outlet, and a stack connected to the gas outlet.

Abstract: To separate tritium from gases and/or vapors escaping accidentally from a clear reactor, before the gases or vapor are discharged into the atmosphere, the gases or vapor are fed through a line 5 into a reservoir 3 of deionized light water which is maintained at its boiling point in a heat insulated vessel 1. The tritium is accumulated in the water in the reservoir 3 and any tritium which passes from the reservoir 3 in light water steam is condensed by surface condensors 8 in a steam dome 9. Any possible residue of tritium in the steam leaving through an outlet 10 at the top of the dome 9 is separated out in the form of droplets by a drier cyclone connected directly downstream of the outlet 10.

Abstract: A process for purifying flue gases by conducting the hot gases through a dry purification stage, and then through a pebble bed evaporator containing pebbles and a liquid. The flue gases then exit the pebble bed evaporator and are washed in a wet washing step. Waste liquid containing dissolved material from the wet washing step is then used as the liquid in the pebble bed evaporator; as this liquid evaporates in the pebble bed evaporator, solid precipitate forms on the pebbles. This solid precipitate is removed from the evaporator and is stored. Vapor from the pebble bed evaporator is condensed and used in the wet washing step. The purified flue gases exiting the wet washing step pass through a filter stage and are discharged.

Abstract: A filter system for a hot cell comprises a housing adapted for input of air or other gas to be filtered, flow of the air through a filter element, and exit of filtered air. The housing is tapered at the top to make it easy to insert a filter cartridge using an overhead crane. The filter cartridge holds the filter element while the air or other gas is passed through the filter element. Captive bolts in trunnion nuts are readily operated by electromechanical manipulators operating power wrenches to secure and release the filter cartridge. The filter cartridge is adapted to make it easy to change a filter element by using a master-slave manipulator at a shielded window station.

Abstract: A vacuum air flow operated cyclone separator arrangement for collecting, handling and packaging loose contaminated material in accordance with acceptable radiological and criticality control requirements. The vacuum air flow system includes a specially designed fail-safe prefilter installed upstream of the vacuum air flow power supply. The fail-safe prefilter provides in-cell vacuum system flow visualization and automatically reduces or shuts off the vacuum air flow in the event of an upstream prefilter failure. The system is effective for collecting and handling highly contaminated radiological waste in the form of dust, dirt, fuel element fines, metal chips and similar loose material in accordance with radiological and criticality control requirements for disposal by means of shipment and burial.

Abstract: The present invention relates to a method and apparatus for replacing a filter placed in a vessel or casing.The filter is placed in a casing, one member of the latter surrounding the filter being slid in order to give access thereto from all sides. Once the new filter has been fitted, it is applied to a frame with the aid of bars having cams, which act on the filter by means of a fastening frame.Application to the filtration of gases containing radioactive dust.

Abstract: A dust collector for radioactive particles includes a housing divided into upper and lower chambers by a partition plate, the upper chamber being formed with a discharge port for cleaned gas and a filter supply port, the lower chamber being formed with an inlet port for a gas to be cleaned and a filter discharge port, a filter holder extending through the partition plate, the filter holder being arranged to enable a filter to be installed from above and to be withdrawn downwardly.

Abstract: A process for the separation of krypton from a radioactive waste gas mixt which is released during the chemical dissolution of burned-down nuclear fuel particles, and which in a carrier gas such as air, in addition to krypton, also contains xenon, argon, nitrous oxide and residual gas components. The waste gas mixture flowing out from a resolver has xenon removed therefrom after purifying the waste gas of nitrous oxides and radioactive residual gas components, such as aerosols, iodine, tritium and carbon(C-14) dioxide; and wherein krypton is finally withdrawn from the residual gas mixture and then stored. The invention also relates to an arrangement for the implementation of the inventive process.

Abstract: A housing for HEPA filters is disclosed, which includes a side access opening for receiving one or more filters, and a filter clamping assembly for seating and unseating each of the filters against its seal. The clamping assembly comprises a pair of filter clamping mechanisms extending transversely across the interior of the housing and along the top and bottom side walls, respectively. Also, a handle is pivotally mounted between the two clamping mechanisms adjacent the opening, and the handle is connected to each clamping mechanism such that rotation of the handle serves to actuate the mechanisms. In one embodiment, the handle is releasably connected to the two mechanisms, and the mechanisms are releasably mounted to the top and bottom side walls, whereby the entire assembly may be disassembled and removed from the housing through the side access opening to permit the repair or replacement of a defective component.

Abstract: Carbon bonded carbon fiber composites as well as ceramic or carbon bonded ceramic fiber composites are very useful as filters which can separate particulate matter from gas streams entraining the same. These filters have particular application to the filtering of radioactive particles, e.g., they can act as vents for containers of radioactive waste material.

Abstract: A plurality of individual filters extend in line across a duct for a gas flow and the duct can be located within secondary containment. The pressure of gas within the duct is less than external pressure and the filters can be supported by a guideway which extends across the duct between opposing walls of the secondary containment with the interior of the guideway communicating with the secondary containment to provide an inward flow purge. The filters in the line are replaced individually by inserting a replacement filter into the line at one end and retrieving the displaced filter at the opposite end of the line.

Abstract: A pressurization and filter installation for shelters, notably of the substantially horizontal tubular tunnel type, comprises at least one entry-exit section communicating with a respective entry-exit airlock. This is adapted to be pressurized, in use, to a pressure higher than the normal external pressure. There is an armored door on the outside of the airlock. There is a sealed door on the inside of the airlock, controlling access to the shelter interior. The shelter interior is pressurized to a pressure higher than that in the airlock. Filter units are disposed in the airlock. Each filter unit comprises at least one absolute filter and at least one activated carbon filter. The shelter provides protection against the effects of nuclear, biological and chemical weapons.

Abstract: A plurality of holding tubes are respectively mounted in apertures in a partition plate fixed in a housing receiving gas contaminated with particulate material. A filter cartridge is removably held in each holding tube, and the cartridges and holding tubes are arranged so that gas passes through apertures therein and across the partition plate while particulate material is collected in the cartridges. Replacement filter cartridges are respectively held in holding canisters mounted on a support plate which can be secured to the aforesaid housing, and screws mounted on said canisters are arranged to push replacement cartridges into the cartridge holding tubes and thereby eject used cartridges therefrom.

Abstract: An essentially air tight plastic bag is disclosed, together with a novel method of replacing such bag on the flange surrounding the side access opening of a HEPA filter housing and in accordance with the conventional bag-out, bag-in procedure for removing a potentially contaminated article, such as a filter, from the housing. The novel method includes moving the article through the side access door into the bag, gathering the bag together at a location intermediate the filter in the bag and the open end of the bag, and circumferentially compressing the gathered portion of the bag at two closely spaced apart locations by means of two metal compression bands. The manner in which the bands are applied results in sufficient compressive force at each location to form an essentially solid sealing plug having the appearance and physical characteristics of a rigid, solid rod segment.

Abstract: A filter system particularly adapted to remove particulate aerosol and vapor contamination from air comprising, an outer shell having a contaminated air inlet cap connected to one end and a clean air outlet cap connected to the other end, and a plurality of filter units mounted axially in the shell, each of said units comprising two containers, one of the containers having a particle/aerosol filter element therein such as paper, and the other of the containers having a vapor filter element therein, such as charcoal, the two containers of each filter unit being positioned in contiguous relation. A vapor passage is provided from one container to the other container of each unit and an annulus is provided between the outer periphery of the containers and the inner surface of the shell.

Abstract: A housing for mounting HEPA filters includes an open-ended tubular casing (12) and, within said casing, slide structure (24) for slidably mounting a HEPA filter therein from one of the ends of the casing. Baffle means (18) divides the interior of the casing into respective chambers (20, 22) which, on mounting of the filter in the slide structure (24), are gastight isolated from each other except by way of the filter and which are accessible from a respective one of the open ends of the casing. Also provided are gas intake/exhaust ports (46, 48) for each of the chambers (20, 22), a pair of cover members (14, 16) for closing the respective open-ends of the casing (12), each of which cover members (14, 16) includes a flange (94) complementary to the associated end of the casing (12), and respective clamp and seal means (100, 84) for clamping the cover members (14, 16) to the casing to effect gastight engagement of the flanges (94) with the respective ends of the casing (12).

Abstract: Hot gas filter for separating solid particles carried along in high temperature or waste gases having a filter casing made of heat-resistant brickwork, in which there is provided at least one oblong filter cell one end of which ends in a hot gas supply duct whereas the other end is tightly closed by a removable cover. The walls of the filter cell are at least partly made of perforated bricks, through which the hot gas entering the filter cell may overflow to a treated gas discharge duct. The filter cell is lined over the whole length thereof with a replaceable filter hose of heat resistant fabric or tissue, preferably non-woven ceramic fiber fabric or a fabric of ytrium-oxide stabilized zircon-oxide fibers.

Abstract: An improved device for effectively removing radioactive particles in moist gas has a pipe for feeding therethrough a moist gas containing radioactive solid particles, a solid-gas separation filter disposed in the pipe, a microwave generator and a wave guide connected between the pipe and the generator. Within the wave guide there is disposed a shielding plate capable of passing the microwave therethrough and preventing the spreading of contamination. Microwave from the generator is applied to the filter by means of the wave guide, and moisture condensate and the like on the filter is heated and evaporated by the microwave to minimize clogging of the filter.

Abstract: Filter elements with changing devices and contamination protection are disclosed. The filter elements are installed in waste tanks and serve to separate substances which are prejudicial to the health when breathed and are used to process air of ventilation systems used in nuclear installations. Two series-arranged standard waste tanks having a coarse material filter layer in one tank and a suspended material filter in another tank are interconnected by a detachable cover constructed for air guidance purposes by means of a lockable, air carrying pipe closable by means of flaps for carrying the supply and spent air which are fixed in a stationary manner to inclined juxtaposed dust laden and clean air ducts with lateral connections. The waste tanks with the incorporated filters can be centrally remotely controlled from one side by lever-transmitted resilient locking systems and can be manually fitted and detached as well.

Abstract: The invention relates to a process and an apparatus for the replacement of a filter placed between the contaminated area and the uncontaminated area of a vessel.The filter is surrounded by a tightly sealed bag as from the uncontaminated area and this bag is sealingly fixed to the outer periphery of a supporting frame. The filter is removed from the supporting frame and placed on the bottom of the tightly sealed bag, which is welded at two spaced points. The bag is then cut between the two welds so as to obtain a tight diaphragm separating the two areas of the vessel. A supplementary supporting frame is then sealingly fixed to the supporting frame and a new filter is fitted from the uncontaminated area of the vessel. The tight diaphragm is then removed from the contaminated area.

Abstract: In a mist collector for separating drops of liquid from a gas or vapor stream and including a cylindrical housing and metal fiber webs mounted in an annular configuration in the housing and arranged to be penetrated by the stream in the radial direction of the housing, the metal fiber webs are composed of a plurality of cylindrical layers spaced apart from one another in the radial direction and the collector is provided with stream conducting elements positioned and arranged with respect to the housing for causing the stream to flow through the layers in a radial inward direction.

Abstract: A method of and an apparatus for removing radionuclides from a radioactively contaminated liquid, especially water from the sump of a nuclear electric-power generating plant, in which the waste water is evaporated to produce a vapor phase containing radionuclides in the form of liquid or solid aerosol-dispersed particles which are collected by passing the vapor through an electric field. Preferably a plurality of such fields are traversed in succession by the aerosol.

Abstract: A filter material charging apparatus for adding a gas treating material into gas treating cells contained in a filter housing includes an open bottomed gas treating material conveying channel and air evacuation conduits located in the filter housing over the gas treating cells. Air-borne filter material is delivered to the conveying channel from a source outside the filter housing. Baffles are located in the channel to distribute gas treating material over the length and breadth of the filter housing, and into the gas treating cells as the gas treating material exits the channel through its open bottom. The air which carried the filter material into the housing is evacuated from the interior of the filter housing by the air evacuating conduit.

Abstract: An upwash, upflow or downflow, graded sand bed dust collector has a reusable imperforate or slightly porous diaphragm on the top of the graded filter media and an inlet for pressurized gas above the diaphragm for inflating the diaphragm against the media during dust removal stage. The dust collector housing can be flared upwardly and outwardly at selected portions to reduce the velocity of upflowing gas during wash stage for improved grading of the filter media. A natural foraminous layer may be self-grading at the top of the filter media, allowing a circumferential or side outlet for filtrate. A layer of fine, dense filter media may also be used to increase the size range of media particles in the dust collector. Special diaphragms may be composed of individual leaflets that rise above the filter media but not to the level of the gas exit during the wash stage, and which settle on top of the filter media during the filter stage.

Abstract: Fully chlorinated and/or fluorinated hydrocarbons are used as gas scrubbing liquids for preventing noxious gas emissions to the atmosphere.

Abstract: A filter assembly for particle-in-gas filtration comprises ducts leading to a filter housing which is removable from the ducts and is provided with covers to prevent egress of material from the housing during transport. Covers may be also provided for the ducts. The surfaces of the duct cover and housing cover which are exposed to the environment when the housing is removed may be shielded while gas is passed through the assembly to minimize the exposure of the surfaces to the gas passing through the assembly.

Abstract: As a safety measure to reduce the content of fission and activation produ in the gas atmosphere contained within a nuclear reactor building after a so-called hypothetical malfunction, in a high-temperature gas-cooled reactor, the gas atmosphere within the reactor building is dusted with at least 0.5 kilogram, preferably more than 1 kg per 50 m.sup.3 of gas atmosphere volume, with particles having an average effective particle diameter in the range between 0.3 to 5 .mu.m, preferably of a material inert to oxygen, such as bentonite or clay, although graphite particles may be used if they are carried into the space with an inert gas carrier. The dusting is performed by a pneumatic system comprising a source of compressed gas, such as air or nitrogen, located outside the reactor building, and feed pipes feeding a pattern of dusting nozzles distributed over the ceiling of the interior space of the reactor building.

Abstract: Method and device for effecting radioactive offgas filtration by means of a mass of filter material, and filter material regeneration, at temperatures in excess of 500.degree. C. in which substances to be filtered impinge on the filter material mass in at least one direction, filtration being effected by removing a layer of contaminated filter material in the direction opposed to the direction in which substances impinge on the filter material in order to remove the filtered substances for filter cleaning. Removal of the contaminated filter material is carried out by adding a fluxing agent to the filter material at operating temperatures for regenerating the filter material by means of a cleanup melt. This fluxing agent may be a glass frit, an alkali hydroxide or an alkali or alkaline earth metal salt.

Abstract: Apparatus for the separation and recovery of a solid product transported by a gas, wherein said apparatus comprises at least one filter cartridge made from a rigid porous material mounted in a sealed enclosure and defining in the latter a first filter chamber within the at least one cartridge and which communicates by its lower end with a tube for the collection of the separated solid product and a second chamber for the collection of the filtered gas outside the said at least one cartridge, the latter having two large-surface opposite porous walls maintained with an appropriate spacing by spacers fixed on the said walls and disposed in the filter chamber in such a way as to form deflectors, means for introducing the gas transporting the solid product to be separated into the said filter chamber and means for extracting the filtered gas from the collection chamber.

Abstract: A filter chamber provided with a side wall having a row of uniformly spaced openings therethrough also has an end wall provided with an access door from which a track extends along the side wall below the openings. Filter units are insertable through the door for placement on the track. A rod extending lengthwise of the track and having an outer end accessible through the door is supported for axial movement back and forth parallel to the track between inner and outer positions. At longitudinally spaced intervals greater than the width of a filter unit lugs project from the rod, all in the same direction. There are as many lugs as the wall openings. The rod is rotatable to turn the lugs from positions in which they will overlap one side of filter units on the track to positions that permit the lugs to be moved to the opposite side of the filter units.

Abstract: A plurality of filter elements which are located in waste containers is disclosed. The filter elements serve for the precipitation of materials which are injurious to health from air streams, and in particular, from air streams in the field of nuclear installations and the disposal of said materials.

Abstract: A high efficiency air filter having a channel formed in the front peripheral surface thereof which is substantially filled with a fluid of high consistency and which is adapted to effect sealing engagement with a mating retaining flange mounted in the housing. A pair of resilient wiper lips extend across the top of the channel from opposite sides thereof to thereby contact the sides of the retaining flange while the filter is assembled in the housing, and then wipe both sides of the flange during withdrawal of the filter from the housing to thereby retain substantially all of the fluid within the channel and prevent the build-up of possibly contaminated fluid on the retaining flange.

Abstract: An apparatus for neutralizing and purifying air comprises an air filter, a preliminary drier, two alternately operable driers, a turbine for moving the air, a cooling unit, a heating unit, a moistening unit, at least one conditioner, and connecting means for outputting the treated air. The cooling unit lowers the temperature of the air, and comprises a separator for liquids and a separator for solids. The heating unit brings the temperature of the air back up to between 250.degree. and 450.degree. C.

Abstract: In a filter assembly for particle-in-gas filtration, filter units are supported on a horizontal partition in the filtering position and are raised from the partition and moved horizontally to enable the filter units to be replaced. The invention may be used in nuclear installations.

Abstract: A damping tube-shaped bypass measurement section with protective maintenance features and continuous flow velocity scanning on absorptive filtration units in the nuclear engineering field is disclosed. The bypass measurement section comprises a tube-shaped bypass measurement section, having single or double elements, for absorption filters, featuring at least one shut-off device, and including an absorption layer thickness connected to the main filtration unit which is to be controlled or monitored, and provides for an equivalent absorption layer thickness.

Abstract: A process for the insertion and exchange of the filter elements for suspended matter is performed from the clean-air-side. During the insertion of a filter element, a plastic tube (which encircles the circumference of the filter element and which exceeds in its length the layer thickness of the filter element several times) is tightly connected in its middle section with the side walls, which side walls form a border around the filter element; and then the open end of the plastic tube, which faces the frame, is connected by way of a tight fit with a ring, which is actually known and which surrounds the orifice of the frame into which the filter element is inserted. The filter element is connected with the frame by means of tightening devices, and the outer free end of the tube is turned inside out and around the filter element for the purpose of unhindered air passage through the filter layer, that during the exchange of the contaminated filter element, the outer open end of the tube is heat sealed.

Abstract: Discharge apparatus for filter assembly for radioactive contaminants, the filter assembly including a housing with at least one filter bed therein, the discharge apparatus including a first conduit in fluid communication with an outlet from the filter bed, a closed tank in fluid communication with the first conduit and a second conduit, the second conduit being in fluid communication with a vacuum means with a filter element disposed between the tank and the vacuum means. Upon activation of the vacuum means, the vacuum means pneumatically conveys the filter material from the filter bed.