Showing papers on "Diffuser (sewage) published in 1998"

Method for making micropumps

Abstract: This invention provides a method by which the performance of reciprocating NMPV (No-Moving-Parts-Valve) micropumps can be optimized for a given choice of valve design, e.g. for diffuser/nozzle valves, rectifier valves etc. The method can more generally be used to design and produce NMPV micropumps with structures optimized for maximal pump performance. The method can further be used to design and construct NMPV pumps significantly smaller in size than those currently available to the art without significant loss in pump performance.

Valve-less diffuser micropumps fabricated using thermoplastic replication

Abstract: This paper presents valve-less diffuser micropumps fabricated using thermoplastic replication Thermoplastic replication is very suitable for a valve-less diffuser pump due to its simple planar geometry Two different thermoplastic replication methods have been tested: hot embossing and injection molding We use 01 and 02 mm deep precision-milled brass mold inserts and 20 and 80 μm deep microelectroformed nickel mold inserts defined from deep reactive ion etched (DRIE) silicon wafers For the injection molding a commercially available compact disc injection-molding machine (Toolex Alpha MD100) is used to fabricate the diffuser micropumps The cycle times are extremely short, less than 10 s per disc, and one properly fabricated nickel mold insert can be used to fabricate more than 10 000 plastic discs The plastic material cost is about 5 cents per disc Tested pumps reach a maximum volume flow of 12 ml min−1 and a maximum pump pressure of 16 kPa

Electroplating uniformity by diffuser design

Abstract: Workpieces, such as semiconductor wafers, are electroplated with improved thickness uniformity by providing a diffuser member intermediate the cathode and anode of a fountain-type electroplating apparatus. The diffuser or member has a pattern of openings specifically designed to prevent channeling and/or selective directing of electrolyte towards the workpiece. In one embodiment, the diffuser member comprises a spiral-shaped pattern of openings originating at the center of the diffuser member and extending to the periphery thereof.

Rear projection screen incorporating diffuser

Abstract: A rear projection screen (10) including a plurality of refracting beads (1) bound in optical contact with a substrate (12) is disclosed. The beads are surrounded by an opaque matrix (2). A diffuser (28) is positioned such that light traveling through the screen (10) will pass through the diffuser (28) after passing through the beads but before exiting the screen (10).

Gas diffuser having varying thickness and nozzle density for semiconductor device fabrication and reaction furnace with gas diffuser

Abstract: A gas diffuser for semiconductor device fabrication has the form of a hermetic cylinder with a hollow formed therein and is provided with a gas inlet opened upward for the gas to flow into the hollow, and a disk-shaped diffusion plate disposed in the lower side thereof with a plurality of nozzles to direct and control the stream of the gas pouring out of the hollow. The thickness of the diffusion plate increases with radial distance from the center thereof, such that lengths of the nozzles through which the gas passes also increase with radial distance from the center of the diffusion plate. A reaction furnace has the gas diffuser disposed in an upper portion thereof, and a support plate for supporting the wafer disposed in a lower portion thereof. The distance from the surface of the wafer to the diffusion plate of the gas diffuser is half the radius of the wafer.

Hot air diffuser for a jet engine air inlet cowl with de-icing circuit

Abstract: The present invention relates to an air inlet cowl (9) for a jet engine, especially for an aircraft. According to the invention, the diffuser (12) of hot air for de-icing, arranged in the hollow leading edge (16) of the cowl (9) is in the form of a polygonal ring and is fixed by elastic support tabs (24) each equipped with a ball joint (25) holding a straight portion (22) of the polygonal ring.

Submergible centrifugal pump having improved diffuser bushings

Abstract: A submergible, centrifugal pump utilizes an improved bushing system for absorbing downthrust at each stage of the pump. The centrifugal pump is a multi-stage pump having a plurality of impellers keyed to a rotatable shaft. Diffusers cooperate with the impellers to conduct the pumped fluid upwardly from one impeller to the next. The improved support system comprises simple diffuser bushings that are generally cylindrical in shape, and relatively inexpensive to manufacture. Each diffuser bushing is disposed between a diffuser and the next upwardly sequential impeller to support that impeller with respect to the downthrust created during pumping.

Characterization of gas transfer and mixing in a bubble column equipped with a rubber membrane diffuser

Abstract: Gas transfer and mixing were characterized in a 32-L bubble column reactor equipped with a commercially available rubber membrane diffuser. The performance of the membrane diffuser indicates that the slits in the membrane are best described as holes with elastic lids, acting as valves cutting off bubbles from the gas stream. The membrane diffuser thus functions as a one-way valve preventing backflow of liquid. Our design of the bottom plate of the reactor enabled us to optimize the aeration by changing the tension of the membrane. We thereby achieved mass transfer coefficients higher than those previously reported in bubble columns. A strong dependence of mass transfer on gas holdup and bubble size was indicated by estimates based on these two variables. The microalga, Rhodomonas sp. , sensitive to chemical and physical stress, was maintained for 8 months in continuous culture with a productivity identical to cultures grown in stirred tank reactors. Copyright 1998 John Wiley & Sons, Inc.

Centrifugal blower assembly with a diffuser

Abstract: A centrifugal blower assembly for a heat exchanger system of an automotive vehicle is described. The centrifugal blower assembly includes a diffuser section interposed between the centrifugal blower housing and a heat exchanger housing in the heat exchanger system. The diffuser section has a pair of non-linear, curved side walls which allow for expansion of the air flowing therethrough to minimize air flow separation against the side walls of the diffuser.

Bearing isolator with air purge

Abstract: This invention discloses an improved seal utilizing an air purge to remove contaminants. The seal (1) is most useful on spindles (10) and utilizes a combination locking ring and diffuser ring (18) to diffuse the air within the seal (1) member itself. The pressurized air is passed from the diffuser (18) into at least one cavity or chamber (31) which is within the rotor of the seal (1) and which, because of its rotation as the rotor, provides a centrifuging effect to efficiently and completely remove contaminants, including the liquid or air, and thus preventing the contaminants from reaching the bearings which the seal or bearing isolator is protecting. The bearing isolator or seal element will operate efficiently with or without air pressure, but operates more efficiently with a very small air pressure applied to the diffuser (18) and locking element.

Air diffuser valve

Abstract: An air diffuser system contains a manifold and a plurality of elastomeric "duckbilled" check valves. The manifold is constructed from a conduit material and can be arranged in many different configurations. The valves are made from an elastomeric material, such as rubber, preventing the valves from being clogged with sludge, sediment, or other debris commonly found in waste treatment water. Additionally, the valves can be bored with predetermined orifice sizes, allowing the volume and pressure of escaping air to be determined prior to installation. To make installation of the valves easier, various types of coupling devices may be used to attach the valves to the manifold. Examples of coupling devices include restrictive orifices, "Y"-shaped conduits, and nipple conduits. Multiple valves can also be fabricated on a common cuff prior to installation.

Ozone distribution in an enclosed space

Abstract: An ozone distribution system is herein described for an enclosed space defined within an enclosure having at least one vent through which gases can escape from the enclosed space. The system comprises: a first tube having an interior and extending through at least a portion of the enclosed space; at least one diffuser integrally connected to the first tube, having an interior in communication with the interior of the first tube, and also having a plurality of spaced outlets; a second tube having at least one outlet positioned in the interior(s) of the diffuser(s); an ozone generator for generating ozone and establishing a flow thereof through the second tube to and through the outlet(s) of the second tube such that ozone is released into the interior(s) of the diffuser(s); and an air intake fan for taking in air from outside the enclosed space and establishing a flow thereof through the interior of the first tube, into the interior(s) of the diffuser(s), and through the outlets of the diffuser(s) so as to carry ozone therewith for distribution in the enclosed space. According to another aspect of the invention, an ozone distribution method uses the above-described tubes and ozone generator to distribute ozone in an enclosed space. Preferably, the enclosed space is maintained at a pressure above that pressure outside the enclosed space.

Propellant based aerosol generating device and method of use

Abstract: An aerosol generating device comprising a casing having a base end and a ainer end, with a firing primer mounted through the base end and extending into a propellant zone which contains a propellant. The firing primer is thereby detonationally connected to the propellant. A diffuser plate is mounted inside of the casing on a side of the propellant zone opposite to the firing primer. A filler area inside of the casing is adjacent to the diffuser on an opposite side to the propellant zone. The filler area contains particles of a powder having interstitial void space between the particles. A frangible end seal is attached to the casing within the retainer end, with the frangible end seal being positioned adjacent to the filler area on an opposite side of the diffuser. When activated, propellant gases expand through the diffuser into the fill area deagglomerating and fluidizing the powder particles and increasing pressure until the end seal ruptures and releases an aerosol cloud. A method for disseminating an aerosol using the device is also disclosed.

Jet pump sensing line T-bolt clamp electrode discharge machining tool

Abstract: An electrode discharge machining (EDM) apparatus for machining slots in a jet pump diffuser in a nuclear reactor pressure vessel is described. The apparatus is configured to machine a plurality of slots in the diffuser at positions behind the diffuser sensing line within the plane formed by the center of the diffuser and the sensing line. The apparatus includes a housing, a plurality of clamp assemblies, a hook assembly configured to engage the sensing line standoff so that the apparatus is positioned at an angle from a plane formed by the center of the diffuser and the sensing line, and a plurality of electrode assemblies. The EDM apparatus can be configured to be installed clockwise or counter-clockwise around the sensing line depending on the spacing available around given diffusers. The EDM apparatus is capable of burning a plurality of slots at the same time, thereby saving time and money.

Automotive air bag device

Abstract: An automotive air bag device offers ready installation in an automobile instrument panel while reducing material and assembly costs and maintaining its structural integrity when activated. An air bag inflation opening, formed in the instrument panel, is surrounded by an internal reinforcement wall. An air bag lid, which covers the opening, includes an inwardly directed leg which engages the reinforcement wall. A case, which supports an inflator and a diffuser, is fastened to the leg on the lid.

Acoustical diffuser assembly and method of installation

Abstract: Apparatus for supporting an acoustical diffuser panel within a structure. A preferred apparatus includes a rigid support member fabricated from an acoustically absorptive material. The support member has a bottom and upstanding side walls that define a well that is sized to receive a diffuser panel therein. The diffuser panel may comprise a plurality of column members that are integrally formed with a planar bottom surface and extend therefrom. At least one column member is longer than at least one other column member. Another diffuser panel that can be successfully used has a series of elongated columns that extend for the width or length of the panel. At least one column member extends a distance above the bottom of the support member that differs from the distance that another column extends above the support member when the panel is received therein. A method for installing at least one acoustical diffuser assembly into a wall structure and an acoustical wall structure are also disclosed.

Non-circular cooling hole and method of manufacturing the same

Abstract: The method involves selecting the shape and size of the cross-section surface, an axis of the supply section and the depth of a diffuser section and the shape and size of its exit surface at the outlet. A passage bore is formed with a cross-section surface inside the selected cross-section surface of the supply section. The diffuser section is cut by jet boring, so that it is inside the selected cross-section surface in the region of the supply section.

Compact hi-spin gas burner assembly

Abstract: A burner apparatus having a burner tube in which is disposed a premixing tube having air communication with the air inlet end of the burner tube. An air diffuser bridges between the premixing tube and the burner tube. A baffle plate is supported by and seals across one end of the premixing tube and a plurality of gas/air mixture injection holes are dispersed in the premixing tube between the air diffuser plate and the baffle plate. A gas tube extends into the premixing tube and a plurality of gas holes are disposed along the gas tube in proximity to the discharge end of the gas tube so that air is premixed with gas and discharged from the gas holes to form a gas/air mixture which is passed from the gas/air mixture injection holes radially between the baffle plate and an air diffuser plate.

Sub-soil domestic wastewater treatment apparatus having multiple aeration chambers

Abstract: A sub-soil wastewater treatment vessel, especially for wastewater produced by single family residences and small businesses and the like. The vessel is divided into at least three contiguous chambers by at least two transverse walls, forming at least two contiguous aeration chambers and a clarifier chamber. Wastewater flows into the first aeration chamber via an influent line, thence through an opening in the first transverse wall into the second aeration chamber. From there, wastewater flows through passages at the bottom of the second transverse wall into the clarifier chamber. Air is supplied to the first and second aeration chambers via low pressure diffuser lines. Three inclined surfaces within the clarifier chamber direct solids through passages in the second transverse wall back into the second aeration chamber for further processing. An effluent line connected to the clarifier chamber permits wastewater outflow.

Turbine exhaust cooling in a microturbine power generating system

Abstract: A microturbine power generation system includes a turbine having a diffuser. A plurality of openings are located in the diffuser. When an exhaust stream is leaving the turbine, ambient air is drawn through the openings and into the turbine exhaust stream. The ambient air lowers the temperature of the turbine exhaust stream.

Cooling air diffuser for computer enclosure

Abstract: A computer has an internal chassis with a variety of electronic components. The chassis is mounted within an enclosure having a ventilation port for exhaust air on a lower surface. A diffuser is mounted to the lower end of the enclosure. The diffuser has a series of openings and baffles which align with the ventilation port for directing the flow of exhaust air away from either side of the computer. The diffuser also allows for full containment of hot or flaming parts to satisfy safety codes. In addition, a pedestal is detachably coupled to the diffuser and is configured to enhance the air flow performance of the diffuser.

Method of forming a film cooling orifice

Abstract: of EP0985802Process for forming a film cooling boring (20) in a wall (10) of a tool comprises selecting the shape and size of the feed section and the diffuser section of the boring to achieve a required blowing rate of cooling air, selecting the required thickness of the coating (16) and the direction from which the coating occurs, and producing a film cooling boring in the wall of the tool so that the boundary surfaces of the diffuser section are displaced corresponding to the required thickness of the coating, the coating direction and the angle of inclination of the boundary surface around a path to produce the selected structure of the boring.

Device of preventing clogging of filter media in biological filter tank and method thereof

Abstract: PROBLEM TO BE SOLVED: To prevent clogging of filter media in a biological filter tank of a sewage septic tank. SOLUTION: At the time of back-washing the biological filter tank, hollow filter media in a filtering treatment zone and hollow filter media in an aerobic treatment zone are washed by fluid contact caused by an aeration stirring action from a back washing device G, and also a portion of the hollow filter media in the filter treatment zone is floated on the upper side of a diffuser S, and a portion of the hollow filter media in the aerobic treatment zone is settled at the lower side of the diffuser S to be mixed, and these processes are repeated, thus the hollow filter media in the tank are exchanged up and down properly and the treating function is converted. COPYRIGHT: (C)2000,JPO

Pre-compression nitrox in-line blender

Abstract: The pre-compression nitrox in-line blender of the present invention has, at an upstream end, an oxygen diffuser for diffusing into an annular cavity of the diffuser oxygen supplied into an innermost cavity from a selectively adjustable pressure regulator regulating a high pressure oxygen reservoir. The annular cavity of the oxygen diffuser communicates, by an air intake aperture in the diffuser, with ambient atmospheric air, whereby a low relative air pressure within the annular cavity draws the ambient atmospheric air through the air intake into the annular cavity. A downstream end of the annular cavity is mounted or mountable to, so as to communicate in unimpeded gaseous communication with, an upstream end of an in-line turbulent mixer. The turbulent mixer is mounted within a sealed conduit, which may be wholly or partly flexible along its length, for generally homogeneous mixing of the oxygen and the ambient atmospheric air so as to form homogeneous nitrox gas as the oxygen and the ambient atmospheric air pass through the turbulent mixer along the sealed gas conduit. A downstream end of the sealed gas conduit is mounted or mountable to, so as to communicate in unimpeded gaseous communication with, a compressor. An oxygen level monitor is mounted or mountable to the sealed gas conduit for sensing and reading out the oxygen level of the nitrox gas within the sealed gas conduit as the nitrox gas flows along the sealed gas conduit under the influence of reduced gas pressure within the sealed gas conduit and oxygen diffuser due to gas intake by the compressor.

Method and apparatus for laser imaging with multi-mode devices and optical diffusers

Abstract: Multi-mode laser radiation is focused to a preselected spot size on a recording construction using a controlled-angle diffuser. The diffuser concentrates the radiation, counteracting the dispersive effects of multi-mode output.