Abstract: The invention relates to a ventilation element for the introduction of a gas into a liquid, having at least one gas port, having at least one carrier plate and having at least one elastically deformable diaphragm which is connected to the at least one gas port and/or to the at least one carrier plate. A space that can be formed between the at least one diaphragm and the at least one carrier plate is connected in terms of flow to the gas port. The at least one carrier plate has a multiplicity of gas outlet openings, and at least one diaphragm is composed at least in sections of a material with a lower density than water, or is equipped with at least one float body which has a lower density than water.

Abstract: A liner for use with a basin to contain a liquid features a plurality of bodies of flexible plastic. Portions of an inner face of a first body of flexible plastic are joined to corresponding portions of an inner face of a second body of flexible plastic, through which a plurality of openings are formed, to provide a multi-layer body of flexible plastic. Other portions of the inner face of the first body of flexible plastic are not joined to corresponding other portions of the inner face of the second body of flexible plastic, defining an air conduit between the first body of flexible plastic and the second body of flexible plastic for guiding pressurized air substantially from an air discharge apparatus.

Abstract: A method of operating an immersed microporous membrane module includes a step of monitoring membrane performance to sense the onset of sludging in the module. Differences in permeability between permeation in backwashes, or trends in permeability during backwashing and permeability during permeation, or both, are monitored. Solid deposits formed during the onset of sludging may be removed with an in situ de-sludging process. For example, the deposits may be removed by stopping permeation while aerating the module, optionally at an increased rate. At other times, the module is optionally aerated while permeate is withdrawn at an aeration rate correlated to flux. The method may be used in particular with a membrane module having parallel textured flat sheet membranes suspended between a pair of vertically oriented headers. An aerator may be made from an open bottomed channel having an array of holes rising and concentrated towards the center of the channel.

Abstract: An aeration assembly for aerating liquids including wine and other alcoholic beverages includes an expansion chamber and an aerating device. The expansion chamber is configured to be in fluid communication with an inside of the uncorked and/or opened bottle when engaged by a bottom portion of the expansion chamber. The aerating device comprises a gas conduit having a proximal end in fluid communication with a distal end. The distal end is disposable below the bottom portion of the expansion chamber. A gas source is in fluid communication with the proximal end of the gas conduit. The expansion chamber is configured to temporarily contain an expansion of bubbles during an aeration process. The expansion chamber and aerating device are not permanently connected, wherein the aerating device can be fully removed from the expansion chamber before, during or after the aeration process.

Abstract: The present invention relates to a process for the preparation of precipitated calcium carbonate allowing for a more sustainable and cost-efficient use of milk of lime. The obtainable products show good optical properties as well as fine particle size distributions.

Abstract: We provide systems for ionic liquid catalyzed hydrocarbon conversion that comprise a modular reactor comprising a plurality of mixer modules. The mixer modules may be arranged in series. One or more feed modules are disposed between the mixer modules. Such systems may be used for ionic liquid catalyzed alkylation reactions. Processes for ionic liquid catalyzed hydrocarbon conversion are also disclosed.

Abstract: A gas-liquid mixing device of a beverage is provided. The gas-liquid mixing device has a container, a liquid inlet pipe, a gas inlet pipe and a liquid discharging pipe configured to discharge liquid, wherein the container is provided with a refrigeration evaporator; the container is further internally provided with a liquid precooling pipe; the liquid entering at the earliest enters the container through the liquid precooling pipe and is stored in the container and cooled by the refrigeration evaporator; the cooled liquid precools the liquid entering the liquid precooling pipe subsequently; the precooled liquid in the container is mixed and dissolved with entering gas; the container is further internally provided with a liquid molecule expander comprising a precooling liquid container inlet and a collision wall; the precooled liquid is ejected to the collision wall through the precooling liquid container inlet.

Abstract: Device for heating a substrate includes a process chamber having a first and a second sealable opening for a substrate to pass through, a first inlet for receiving a process gas and a first outlet for discharging an off-gas; an evaporator for evaporating the material, which evaporator device is connected to the chamber for supplying the process gas; a first condensation device connected to the chamber for receiving the off-gas and condensing the material in the vapour phase in the off-gas to form a solid phase and a second condensation device for condensing part of the material in vapour phase in the off-gas to form a liquid phase, which second condensation device connects the first condensation device to the discharge duct and a connecting duct between the evaporator device and the second condensation device for transporting material in the liquid phase between the second condensation device and the evaporator.

Abstract: An apparatus for mixing fluids within a pipe is provided. In one embodiment, the apparatus includes a fluid mixing device with a pipe having a pipe wall and an axial bore for conveying fluids through the pipe. The fluid mixing device also includes a sleeve disposed about the pipe and a cavity provided between an exterior surface of the pipe and an interior surface of the sleeve. The cavity and the axial bore of the pipe are in fluid communication with one another via an opening through the pipe wall. Additional systems, devices, and methods are also disclosed.

Abstract: Aeration device for bioreactors with a first aeration element with gas outlet openings of a first size and with at least one second aeration element with gas outlet openings of a second size, the aeration elements being formed by a common housing with separate aeration channels.

Abstract: A liquid aerator includes a porous diffuser; a stem connected to the porous diffuser; and a manual air pump accepting an end of the stem, the manual air pump configured such that the aerator can be set onto a supporting structure with the stem and the porous diffuser extending upwardly from the manual air pump.

Abstract: A fixture for delivering a first fluid over the basin of a sink includes a supply inlet and a delivery outlet for the fluid, the inlet connected to the outlet through a hollow body of the fixture, the hollow body including two straight, hollow metal tubes: a first tube arranged to be mounted next to the basin of the sink in use, and a second tube joined to the wall of the first tube so as to project out over the basin of the sink in use. One or more inserts are provided inside the first metal tube and together define a curved elbow duct inside the first metal tube for guiding the fluid from the first metal tube into the second metal tube. The tubes can be cut at relatively low cost from conventional rolled steel tubing, and the curved elbow duct limits pressure losses inside the first tube.

Abstract: A device for distributing gases in liquids, comprising: an aerating element made out of plastic, with an upper side and a lower side joined with the upper side, a support element, and a gas inlet, wherein the aerating element comprises at least one cavity that can be filled with gas through the gas inlet, wherein at least the area of the upper side of the aerating element comprises holes, perforations or the like as the gas outlet, and wherein the support element is situated in the cavity of the aerating element. In order to enable a uniform and reliable aeration of larger water surfaces in a cost-effective manner, it is proposed that the width of the support element be greater than its height.

Abstract: According to an embodiment of the present invention, a gas-liquid circulating type gas hydrate reactor, includes: a reactor body configured to be supplied with gas and water to generate a gas hydrate; and a bubble generator configured to be disposed around a lower portion of the reactor body, wherein the gas supplied from the lower portion of the reactor body is jetted into the reactor body through the bubble generator. The gas-liquid circulating type gas hydrate reactor in accordance with the present invention makes it possible to jet gas at a high speed by using the bubble generator disposed at the low portion of the reactor body so as to promote the reaction of water and gas which are accommodated in the reactor body while forming a water stream at the lower portion of the reactor body that enables a smooth agitation of the water and the gas.

Abstract: A jet plate for directing a flow of air in a cooking chamber of an oven may include a body and a plurality of air delivery orifices. The body may be configured to be disposed along a sidewall of the cooking chamber proximate to a rack or pan support. The air delivery orifices may pass through the body. The air delivery orifices may be disposed to extend transversely across the body and may be distributed along a longitudinal length of the body such that a density of air delivery orifices proximate to one portion of the jet plate is higher than a density of air delivery orifices at another portion of the jet plate.

Abstract: Systems and methods for generating low or ultra-low concentrations of oil-based challenging compounds for filtration media are provided. Embodiments of the generators utilize bypass air in addition to the source of challenge. A HEPA filter which utilizes spunbond scrim material and ePTFE membrane for use in an aseptic pharmaceutical filtration air handling system for installation and testing is provided. The installation and testing configuration includes the ePTFE filter with a low or ultra-low concentration of challenging aerosol in the upstream side of the filter along with a scanning device for determining the upstream concentration, all completed in situ within a pharmaceutical air handling system. At the downstream side of the ePTFE filter is positioned another scanner which may be a discrete particle counter. The system and configuration allows for exposure to ePTFE filtration media for certification by low or ultra-low concentrations of oil based challenging compounds.

Abstract: A device for the pressurization and evacuation of a gas in a bottle, in order to approximate the unopened (ambient) conditions of a previous gaseous state in said bottle. Two units comprise this system, namely a charging unit and a sealing-valve unit. When the charging unit is coupled to the sealing-valve unit three functions can be performed. The first is a priming function where the bottle is partially evacuated of its ambient air and replaced with a gas from a cartridge. The second is a charging function where the primed bottle is pressurized with the same gas type or mixture from the pressurized gas cartridge. The third is an evacuating function where the charged bottle can be bled of gas to achieve the approximate ambient condition of an unopened bottle. This function is used when a bottle is overcharged and a lower pressure is desired.

Abstract: A liquid aerator includes (i) a porous diffuser; (ii) a stem connected to the porous diffuser; (iii) an insert connected to the stem; and (iv) a manual air pump connected sealingly to the insert, the manual air pump configured such that the aerator can be set onto a supporting structure with the stem and the porous diffuser extending upwardly from the manual air pump.

Abstract: A diffuser assembly for a hydraulic reservoir is disclosed. The diffuser assembly includes an inlet tube for connection to the inlet to the reservoir. A middle portion of the middle tube is connected to a plurality of diffusers. The diffusers are disposed at an angle with respect to an axis of the inlet tube and the axis of the inlet to the reservoir so that fluid flowing into the reservoir must change flow directions for entering and exiting the diffusers. The disclosed diffuser assembly is less prone to damaged cause by fluid flow spikes and is particularly useful for high flow/high pressure applications.

Abstract: The invention relates to a device for aerating a suspension held in a treatment tank, in particular wastewater, activated sludge and the like, with a frame having longitudinal spars (1) and a compressed-air diffuser (3), the housing (G) of which has a multiplicity of first connecting pieces (4) for the connection of air diffuser lines (5) and a second connecting piece (6) for the connection of an air feed line, wherein the housing (G) is fastened to the frame such that first axes of the first connecting pieces (4) run approximately parallel to a plane containing the longitudinal spars (1). To simplify assembly, it is proposed that a second axis of the second connecting piece (6) forms an angle of 30 to 60° with the plane.

Abstract: A delivery apparatus includes a volatile agent source, a controller, and an emanator material. The volatile agent source stores a volume of a volatile agent such as a fragrance. The volatile agent source includes an outlet for delivery of the volatile agent from the volatile agent source. The controller controls a delivery rate of the volatile agent from the volatile agent source. The emanator material is disposed at approximately the outlet of the volatile agent source. The emanator material absorbs at least a portion of the volatile agent and maintains the volatile agent until the volatile agent evaporates into an ambient environment.

Abstract: Apparatus and methods are disclosed for facilitating dissolution of one or more gases into a liquid. Preferred gases for use with the apparatus are oxygen, air, and ozone. An apparatus of the present invention includes a dissolution tank that includes a pressure vessel, at least one liquid spray nozzle, and a fluid outlet. The apparatus also includes a gas source, an element for passing fluid into the pressure vessel, and a discharge device connected to the fluid outlet, which discharge device is provided with at least one orifice. Preferred applications include wastewater treatment, treatment of drinking water, fermentation, and bioremediation.

Abstract: A gas diffuser including a grid of aeration pipes spaced apart and in parallel alignment within a horizontal plane is provided. The aeration pipes have improved discharge hole placement along their lengths and around their circumferences to provide improved performance and reduced fouling of membrane filtration systems associated therewith.

Abstract: Method and apparatus discloses a dock having a floatatable aeration system incorporated therein. The dock may be a floating or a fixed pier system having a walkway for users to move about the dock, a plurality of boat berthing slips which may be designed to accommodate one or more boats in each slip, along with individual finger-like docks disposed between each boat berthing area. Incorporated at various locations in the dock is an aeration system that includes aerators having a single or double concaved surface at the top of a fluid intake chamber for diverting aerated fluid away from the enclosure of the aerator.

Abstract: A multi-disc air diffuser according to the present invention comprises a bolt having a vent groove formed in a longitudinal direction thereof; a plurality of discs, each of the discs having a bolt joint section to be passed through the bolt, an air room for holding the air supplied through the vent groove, and a nozzle section having a plurality of nozzles which are arranged in an end part of the air room at a regular size and intervals, wherein the lower surface of each of the discs is more than the upper surface thereof and the outer circumference surface of each of the discs is formed to be inclined; and a backflow prevention section for joining to an end part of the bolt to adhere closely the discs to one another, connecting the vent groove to an air supply pipe, and having a check valve to prevent the air flowing backward from the vent groove to the air supply pipe.

Abstract: An in-bottle aerator for mixing the oxygen in the air with wine as the wine is poured from its bottle. The aerator has at least one air ingress channel extending from one end of the aerator to the other allowing air into the bottle to displace wine exiting the bottle. Air mixing channels draw air from outside the bottle and direct that air to lateral channels that intersect a central flow channel extending from one end of the bottle to another. The air mixing and air ingress channels are preferably arranged to allow the user to pour and aerate wine at the same time and with the bottle in any orientation about its axis. The aerator may be a separately formed component that can be inserted into the bottle by the bottle manufacturer, by a wine bottler or by an enduser. Alternatively, the aerator may be wholly or partly formed as part of the neck of the bottle. A completely and integrally formed aerator may be formed a part of a plastic wine bottle.

Abstract: Provided is a system for dissolving gas into liquid contained within a body. The system may include a tubular body extending between a bottom end and a top end, a gas diffuser coupleable to a gas source and configured for discharging gas bubbles into the tubular body, and a liquid pump for propelling liquid within the tubular body in a downwards direction, against uprising gas bubbles, where the liquid egresses at the bottom end of the tubular body.

Abstract: A sparging device for a flotation cell may include a central gas tube with a central gas orifice which is adjoined by at least two connecting tubes each having a connecting gas orifice, the connecting tubes being aligned at a right angle ss to a longitudinal axis LZ of the central gas tube, the central gas orifice being connected to the connecting gas orifices, and each connecting tube being connected to at least one gas injection unit at its end remote from the central gas tube. A flotation cell with such a sparging device and a flotation method are also disclosed.

Abstract: Provided is a nanobubble generating system and a nanobubble generating method in which nanobubbles exist stably in a liquid phase by a very simple constitution and a very simple process. A nanobubble generating system has a generation chamber for accommodating a gas phase part existing in the upper side and a liquid phase part in contact with the lower side of the gas phase part under sealed condition, a supersaturated dissolved liquid generating device for generating supersaturated dissolved liquid in which a gas is dissolved in the liquid phase part under supersaturated condition, and a nanobubble generating device for feeding a pressurized gas to said supersaturated dissolved liquid via through-holes having a nano-sized opening size to generate nanobubbles having a diameter smaller than 1 ?m.

Abstract: A gas diffuser comprises a grid of aeration pipes spaced apart and in parallel alignment with each other within a common horizontal plane and a manifold in fluid communication with the aeration pipes. A given aeration pipe (12) includes: a length (L) extending between two ends and defining an axis (Z), a hydrodynamic diameter (Dh),an elliptical cross-sectional area defining a vertical plane comprising a vertical (Y) and horizontal (X) axis intersecting through a center (C) which are perpendicular to axis (Z), an outer circumference defined by a first arc (20) comprising 30° located below the (X) axis and bisected by the (Y) axis, and a second arc (22) comprising 330° which is non-overlapping with the first arc (20.

Abstract: Systems and methods for diffusing gas into a liquid are disclosed. In some cases, the methods include tangentially introducing a liquid into a cylindrical chamber having a cylindrical inner wall such that the liquid develops a spiral flow. In some cases, gas bubbles are orthogonally introduced into the liquid as the liquid flows through the chamber. In some cases, a flow of the liquid and the gas bubbles is controlled such that a ratio of a liquid flow rate to a gas bubble flow rate does not exceed values which convert non-bacteria enriched, clear water into froth. In such cases, a mixture of the liquid and the gas bubbles to exit the chamber near an output end. While the liquid can include clear water, in some instances, the liquid also includes bacteria (e.g., surfactant-producing or non-surfactant-producing bacteria) and/or bacterial nutrients that allow for improved bioremediation.

Abstract: A micro bubble generating system includes a shell having a well for retaining a first liquid to immerse an object. A micro bubble apparatus is provide to the shell for providing a pressurized mixture of a second liquid and a dissolved gas into the well so as to create a plurality of micro bubbles within the first liquid for engaging the object.

Abstract: A system for mixing and mixing processes and structures are disclosed. In addition a nozzle used for mixing is disclosed.

Abstract: A gas filtration apparatus includes a first pipeline configured to divide transmitted gas and air to second and third gas flows, transmit the second and third gas flows to second pipeline bundle which is configured to divide each of the second and third gas flows to two or more gas flows and transmit the divided gas flows to a plurality of filters, a purifying tank configured to contain first water for purifying the divided gas flows, a plurality of filters positioned in a lower space of the purifying tank and configured to disintegrate one or more bubbles created by the divided gas flows, and a gas outlet configured to collect a plurality of bubbles emitted from the first water and release the collected bubbles to the outside of the gas filtration apparatus.

Abstract: A micro bubble generating system includes a shell having a well for retaining a first liquid to immerse an object. A micro bubble apparatus is provide to the shell for providing a pressurized mixture of a second liquid and a dissolved gas into the well so as to create a plurality of micro bubbles within the first liquid for engaging the object. One method of using micro bubbles includes providing a fluid mixture, including a saturated gas, to a fluid chamber connected a fitting; and producing a plurality of micro bubbles into a fluid. Another method of using micro bubbles includes providing a fluid mixture, including a saturated gas, into an air entrapment chamber; and producing a plurality of micro bubbles into a fluid.

Abstract: A submersible aeration pump includes a motor housing, an air inlet conduit carried by the motor housing, a pump motor in the motor housing, a rotatable armature drivingly engaged by the pump motor and disposed in air communication with the air inlet conduit and at least one air discharge conduit carried by and disposed in air communication with the armature. Air is drawn from the air inlet conduit, through at least a portion of the armature and is discharged from the at least one air discharge conduit, respectively, by centrifugal force responsive to operation of the pump motor.

Abstract: A method and a device for carbonating a liquid medium, for example a beverage, by introducing CO2 under pressure into the liquid medium via at least one nozzle device (5, 5a, 5b, 21) which is arranged in a housing (3, 3a-c) through which the liquid medium flows.

Abstract: A micro bubble generating system includes a shell having a well for retaining a first liquid to immerse an object. A micro bubble apparatus is provide to the shell for providing a pressurized mixture of a second liquid and a dissolved gas into the well so as to create a plurality of micro bubbles within the first liquid for engaging the object. A micro bubble generating apparatus may include a housing body having a first fluid passage for a pressurized mixture of a liquid and a dissolved gas in a direction towards a fluid flow. An orifice member can be releasably engaged with the housing body and the orifice member may have a second fluid passage being disposed therein; and the second fluid passage being disposed at an angle with respect to the first fluid passage for generating a plurality of micro bubbles from the mixture; and an opening in the housing body for releasing the plurality of micro bubbles.

Abstract: Apparatus and process for dissolving gas in a liquid. The process comprises: tangentially introducing a liquid into a chamber having an inner wall with sufficient volume and pressure to develop a vortex in the flowing liquid; orthogonally introducing gas into the flowing liquid through means located at the chamber inner wall for developing gas bubbles within the liquid. The apparatus comprises: a cylindrical chamber having a cylindrical inner wall, the chamber being oriented in any direction enclosed at both ends and with an entry port to introduce liquid to develop a spiral flow of liquid along the chamber inner wall toward the output end, a porous wall to permit the introduction of gas orthogonally into the stream to develop gas bubbles within the stream, and an exit port to discharge the mixture of gas bubbles and liquid.

Abstract: A compact and portable liquid concentrator includes a gas inlet, a gas exit and a flow corridor connecting the gas inlet and the gas exit, wherein the flow corridor includes a narrowed portion that accelerates the gas through the flow corridor. A liquid inlet injects liquid into the gas stream at a point prior to the narrowed portion so that the gas-liquid mixture is thoroughly mixed within the flow corridor, causing a portion of the liquid to be evaporated. A demister or fluid scrubber downstream of the narrowed portion removes entrained liquid droplets from the gas stream and re-circulates the removed liquid to the liquid inlet through a re-circulating circuit. Fresh liquid to be concentrated is also introduced into the re-circulating circuit at a rate sufficient to offset the amount of liquid evaporated in the flow corridor.

Abstract: An aerator for aerating a liquid within a container having a main body portion and an opening. The aerator includes a pump assembly configured to provide an air flow, a cannulated shaft, and a manifold assembly configured to be fluidly coupled to the pump assembly by way of the cannulated shaft. The manifold assembly is configured to distribute the air flow to a plurality of radially arranged manifold nozzles, wherein the radially arranged manifold nozzles are configured to generate a plurality of air bubbles having a radial velocity configured to direct the plurality of air bubbles radially outward from the manifold assembly such that the plurality of air bubbles travel vertically upwards generally towards the opening of the container without generally contacting the main body portion of the container or the cannulated shaft. For example, the manifold assembly may be configured to generate the plurality of air bubbles having a radial velocity of 2.0 feet/second to 3.0 feet/second.

Abstract: Disclosed is a diffuser installation structure capable of improving uniformity of air bubbles discharged from air bubble discharge holes, restricting the formation of dead zone air bubble discharge holes, and having the tolerance against design deviation. In the installation structure for a diffuser including at least one air feeding port and an air bubble discharge wall having a plurality of air bubble discharge holes, the air bubble discharge wall is inclined upward in the direction of increasing distance relative to the air feeding port.

Abstract: Water circulation systems with air stripping arrangements to treat and remove undesirable disinfectant byproducts from potable water in municipal water tanks, ponds, and other bodies of water. The systems include a flotation platform, dish, draft tube, and an impeller to draw water from the depths of the tank up through the draft tube to be discharged outwardly of the dish to create a primary circulation pattern and an induced, inner or secondary circulation pattern. Each system additionally includes an air stripping arrangement positioned adjacent and about the upper portion of the draft tube and adjacent an upper portion of the secondary flow. The air stripping arrangement includes a plurality of submerged sets of air manifolds wherein pressurized air is supplied to the air manifolds and driven out of them in bubbles to create a treatment zone immediately above each set of manifolds.

Abstract: A system for mixing and mixing processes and structures are disclosed. In addition a nozzle used for mixing is disclosed.

Abstract: A diffuser for oxygenation of aqueous media comprises a manifold connectable to a source of pressurized oxygen-containing gas and having a plurality of outlet ports communicating a hollow interior of the manifold with an exterior thereof. A plurality of flexible microporous tubular membranes each have a coupled end secured to the manifold at a respective one of the outlet ports thereof to communicate an internal passage of the tubular membrane with the hollow interior of the manifold. An elongated rod extends along each tubular membrane within the internal passage thereof to maintain a length of the tubular membrane in an orientation projecting outward from the manifold with the free end of the tubular membrane further outward from the manifold than any other portion of the tubular membrane. The rods prevent curling of the tubular membranes over time when the diffuser is submerged in a liquid medium for use.

Abstract: Aeration device for bioreactors with an aeration element with gas outlet openings arranged in a housing, the aeration element taking the form of a microsparger, the gas outlet openings of which are in each case spaced apart from one another and have a size of between 100 ?m and 200 ?m. At least one second aeration element with gas outlet openings of a second size is preferably provided, the aeration elements being formed by a common housing with separate aeration channels.

Abstract: The disclosed apparatus aeration assembly is used for submersion in and aeration of wastewater contained in a receptacle. The assembly may comprise a non-floating planar grid supporting a plurality of gas diffuser panels. The supporting grid may have at least two ends; one or more gas inlets affixed to one of the at least two ends for supplying gas to the plurality of gas diffuser panels; and one or more lift lines of a predetermined length affixed to each of the at least two ends with all lift lines meeting at a juncture. The juncture may be positioned above a plane of the supporting grid so that the predetermined length of a line affixed to one of the at least two ends is unequal to the predetermined length of a line affixed to another of the at least two ends.

Abstract: The integrated aeration system utilizes a water pump for aeration. Ambient air/gas is entrained by a circulating water jet induced by the pump. The circulating water jet enters a sealed tank, The entrained gas is broken into bubbles after the impingement between the jet and a receiving pool occurs, aerating the receiving pool by water jet spray. The entrained gas/air builds up headspace pressure above the water pool, the headspace pressure being measured by a pressure gauge. The trapped air above the water pool is released when the headspace pressure increases to reach a desired value to aerate a separate tank/container as a diffused aeration or any other aeration process.

Abstract: Uses of a method of producing small bubbles of gas in a liquid include gas transfer in airlift bioreactors and anaerobic digesters, and particle separation. The method uses a source of the gas under pressure, a conduit opening into a liquid and oscillating the gas passing along the conduit. The oscillation is effected by fluidic oscillator, comprising a diverter that divides the supply into respect outputs, each output being controlled by a control port, wherein the control ports are interconnected by a closed loop. Separation of algae from water involves delivering a laminar flow of microbubbles in the range 10 to 100 ?m diameter. Such bubbles also deliver a laminar flow in bioreactors that delivers enhanced liquid flow despite the small bubbles, which improves mixing and also enhances efficiency of gas exchange and retention of the bubbles in the reactor.

Abstract: An aeration system has aerators that remain generally full of air when the supply of pressurized air is turned off or vented. Water does not reach the bubble discharging holes of the aerator, which are kept from plugging. The aerator has a body with a hole through a wall of the body to discharge bubbles. The hole is surrounded by a skirt at the wall of the body. The skirt extends to below the elevation of the hole. The aerator body is connected to a source of pressurized gas through an open bottomed chamber. An opening between the aerator body and the inside of the chamber is located below the elevation of the hole. When the supply of gas is off, water enters the chamber and possibly the skirt. However, the water can only rise until it has reached the skirt and the opening, both of which are below the hole, and the entire aerator body is kept dry. Aerator fouling is reduced, and the aerator begins to produce an even flow of bubbles quickly when the supply of gas returns.