Abstract: Apparatus and propeller for distributing a gaseous, liquid or powdered material in a liquid by rotation in the liquid of a propeller having two or more blades. The blades have a perforated hollow portion connected to a source for the gas. The propeller is rotated at a cavitation producing velocity, and for the distribution of the material in the liquid use is made of the pressures occurring upon the implosion of the cavitations.

Abstract: The device comprises a fluid supply tube immersed in the liquid to be treated. There are disposed coaxially with this tube: an induction enclosure connected to the lower part of the tube and provided with induction orifices for the liquid and means defining a centrifugal pump. The pump is connected to the lower end of the induction enclosure and is adapted to draw in the liquid entering the enclosure in such manner that this liquid itself draws in the fluid supplied by the supply tube, to form in the enclosure an emulsion of the fluid in the liquid and to project this emulsion toward the surrounding liquid.Application in the treatment of drinking and waste waters.

Abstract: Bio-oxidative treatment of aqueous waste by means of a partially submerged rotating biological contactor (or RBC) is improved by suffusing the rising submerged quadrant of an RBC with air furnished within the RBC perimeter. Air is distributed along and outward from the rotational axis and is released between discs of the RBC. Some of the air so released is trapped by protrusions on the discs. Rotation of such RBC is accomplished or at least aided by differential buoyancy imparted by such air suffusion and trapping.

Abstract: An apparatus for mixing a gas and a liquid is disclosed. The apparatus is comprised of a hollow outer tube and a hollow inner tube received coaxially within the outer tube. The inner tube is mounted for rotary motion within the hollow interior of the outer tube. A motor is attached to the outer tube adjacent a first end thereof and is drivingly coupled to a first end of the inner tube. The inner tube has a section which extends beyond the second end of the outer tube. A propeller is attached to this section of the inner tube for rotation therewith. The propeller is adapted to be placed in a liquid and to propel the liquid in which the propeller rotates. An inlet is formed in the inner tube for admitting a gas to the hollow interior of the inner tube. A diffusion tube forms a portion of the inner tube and extends beyond the propeller. The diffusion tube has a hollow interior which forms a portion of the hollow interior of the inner tube.

Abstract: A submerged aeration apparatus has a hollow shaft extending downwards from the surface of a body of liquid. The hollow shaft is used to transfer surface air or other gases to the body of liquid. An outlet for gas near the bottom end of the shaft is positioned below the surface of the body of liquid. An impeller connected to the shaft near the outlet for gas has an aperture adjacent the shaft for drawing liquid towards the impeller and circulating the liquid past the gas outlet for mixing the liquid with the gas, the impeller then expelling the liquid.

Abstract: An efficient apparatus related in general to introducing gas into a body of liquid and more particularly to aerating wastewater contained in an activation basin by means of interacting surface agitation and gas entrainment.

Abstract: A rotor for the distribution of air in the form of finely divided bubbles in the slurry in a flotation tank comprises a boss with an inner hollow air passageway, spaced-apart wings extending radially outwardly from the outer surface of the boss, and multiple air conduits communicating between the inner hollow air passageway and the surface of the boss between each adjacent pair of wings. The air conduits have outer mouths located immediately behind a wing (behind in the sense of rotational direction of the rotor) and linearly extend to the inner hollow air passageway such that lines through their central axes will intercept with imaginary radial lines passing through the centers of the wings behind which the outer mouths of the respective air conduits are located.

Abstract: A method for treating water is disclosed. The method is applicable for the treatment of waste water within lagoons and ponds wherein the treatment of the waste water is accomplished mainly through aeration.

Abstract: The invention concerns a flotation apparatus for separating impurities, such as printing ink, or the like, from a fiber suspension that has been formed from waste paper. The apparatus includes a container for flotation of the suspension. A drive shaft extends into the container, either from above or below. A feed opening for suspension is defined at the bottom of the container. On the drive shaft is a pump impeller for impelling suspension into the container and downstream along the drive shaft. From the pump impeller there is a rotor located on the drive shaft for dispersing air that is introduced to the container by an air feed conduit which emits air into the region of the rotor. The drive shaft itself may serve as the air feed conduit and it may have air outlets at either or both of the pump impeller and the rotor. A foam withdrawal means for withdrawing the foam of impurities generated in the flotation apparatus has an inlet positioned at the axis of the cylinder which is at the axis of the rotor.

Abstract: A method of and an apparatus for aerating and circulating a liquid in a vessel comprising utilizing a surface aerator and a bottom mixing rotor mounted on a hollow common shaft. The rotor entrains liquid and air into the hollow center of the common shaft from the liquid surface region and affects a downward two-phase flow in the hollow center. The gas-liquid mixture is subsequently injected into the liquid body through the channels of the rotor which communicate with the hollow center of the shaft. The discharged jet streams disperse the entrained gas bubbles throughout the liquid body and provide turbulent mixing in the bottom section of the vessel. The present invention not only provides sufficient bottom mixing but also enhances the mass transfer efficiency of the surface aeration by enriching the gas content in the surface layer of the liquid.

Abstract: The present invention relates to a process and an apparatus for dispersing a gas in a liquid flowing within a vertical cycle through two reaction zones arranged in parallel within a reactor, the liquid/gas mixture flowing upwards in the first reaction zone due to the air-lift pump effect and being degassified at the transition from the first reaction zone to the second reaction zone and the completely or partly degassified liquid flowing down and the liquid being remixed with gas (preferably air) at the transition from the second to the first reaction zone below the two reaction zones.

Abstract: Apparatus for maintaining solids in suspension in a liquid mass contained in a vat. Liquid under pressure and compressed gas are injected simultaneously into the liquid by the stirrer arm at the bottom of the vat.

Abstract: PCT No. PCT/US79/00224 Sec. 371 Date April 10, 1979 Sec. 102(e) Date April 10, 1979, PCT Filed April 10, 1979. An apparatus (10, 212) for mixing a gas and a liquid is disclosed. The apparatus is comprised of a hollow outer housing (22) and a hollow inner tube (24) received for rotary motion within the outer housing (22). A motor (61) is attached to the outer housing (22) adjacent a first end thereof and is drivingly coupled to a first end of the inner tube (24). The inner tube (24) has a support tube (214) which extends beyond the second end of the outer housing (22). Propeller blades (216) are attached to the support tube (214) for rotation therewith. An inlet (82) is formed in the inner tube (24) for admitting a gas to the hollow interior of the inner tube (24). The support tube (214) has a diffusion section (222) that extends below the propeller blades (216).

Abstract: To introduce and mix fluids, particularly gas (air) with liquid, which is called sparging, an airfoil blade impeller is used for pumping the liquid and for introducing the fluid to be sparged into the liquid through holes in the suction surface of the blade. The airfoil blades are characterized by camber, thickness and location of holes which result in high stripping efficiency of the gas into the liquid without significant decrease in power use efficiency over conventional sparging systems.

Abstract: A flotation machine is intended to carry out flotation of valuable minerals, such as coal, for example, and comprises a plurality of cells provided with pulp receiving and discharging means. Mounted in each cell above horizontal stator plates and in spaced relationship therewith are aerators. Each stator horizontal plate is formed with a central opening disposed below each aerator. Arranged intermediate the stator plates is a means for regulating longitudinal recirculating streams of pulp, and between side walls of the cell and the stator plates there are arranged means for regulating transverse streams of pulp. Each of the horizontal stator plates is formed with vertical blades arranged all around the aerator at an angle to a vertical plane passing through the center of the aerator, this angle coinciding with the angle at which the pulp is discharged by the aerator. To prevent swirls in the pulp flow under the aerator, a cruciform partition is mounted below the stator plate.

Abstract: A rotor adapted to rotate about a rotary shaft and intended for displacing fluids characterized in that the rotor comprises at least two ridges arranged helically around a core part so that a sectional area at right angles to the axis of rotation comprises at least two lobes with intermediate pits, the depth of the pit measured between the core part and a tangential line to the two lobes one on each side of the pit concerned being at least equal to one third of the distance between the core part and the circle described by the point of a lobe furthest remote from the axis of rotation.

Abstract: A rotating gas diffuser for shearing fine gas bubbles from the surface thereof when the diffuser is immersed in a body of liquid and rotated therein. The rotatable shaft of the diffuser carries a disk like member defining at least one gas plenum having a porous wall out of which gas introduced into the plenum can pass to form nascent gas bubbles which are then sheared off by the viscous shear forces exerted by the liquid in which the disk is rotating. Preferably both the top wall and the bottom wall forming the gas plenum or plenums are porous. The ratio of the overall diameter of the disk to the maximum thickness of the disk in the gas diffusing area occupied by the plenums is at least about 32:1. Improved results are obtained when this ratio is at least about 48:1, more improvement is obtained with a ratio of at least about 64:1, and still greater improvement with a ratio of at least about 128:1. The preferred value of the ratio is at least about 256:1.

Abstract: An apparatus for mixing a liquid and a gas in a tank includes a means for circulating the liquid in the tank and a sparge ring for dispersing gas into the tank. The circulating means includes a plurality of blades extending downwardly from a bottom surface of a disc so that rotation of the blades creates a suction area. The sparge ring introduces gas into the tank in a direction that bypasses the suction area to prevent the gas from flowing into the suction area. Preferably, the sparge ring has a discharge means with a radius that is larger than the distance from the center of the disc to the outer tips of the blades.

Abstract: A driven hollow shaft carries propeller means in the form of a screw-shaped vane which at its lower edge widens to a chamber communicating through a channel with the interior of the hollow shaft and having an outlet opening through which gas supplied through the hollow shaft is discharged into a liquid in which the propeller means are immersed. The chamber is formed by two downwardly diverging screw-shaped surfaces of the vane and has a V-shaped cross section with the apex pointing outwardly from the driven shaft.

Abstract: An improved apparatus for generating finely divided particulate gas bubbles in a liquid. The apparatus includes an outer body with a hollow shaft and a cavity defining means carried by the shaft. The shaft is apertured for communication with a gas supply and the cavity is apertured for communication with a liquid supply. The outer body also carried an inner body which includes a shaft and a plurality of vanes. The shaft of the inner body is journaled for rotation within the hollow shaft of the outer body.

Abstract: An apparatus for introducing gas, e.g. atmospheric oxygen, into a liquid such as waste water or sewage comprises a plurality of ribs of airfoil cross-section and forming venturi nozzles which are first constricted and then widened in the direction of liquid flow. The ribs are formed with minute passages for introducing the gas into the liquid perpendicular to the direction of liquid flow across the ribs.

Abstract: A mixing and aeration impeller is comprised of a hub and a plurality of first flutes interspaced between and joined to a plurality of second flutes. The flutes are adapted to the hub and have troughs which begin proximate the hub and extend radially away from and angularly downward and upward away from a plane normal to a shaft to which the impeller is adapted. The flutes are preferably formed as one unitary structure and shaped in a periodic pattern which may be generally sinusoidal or trapezoidal in cross section normal to the radius of the impeller along the length of the troughs. The impeller includes means to receive compressed air from a source and means to exhaust the compressed air radially outward from the rim. The hub has means to receive the compressed air and to communicate it to a passage or gap formed in the flutes to transmit the air radially outward to the rim. The air is exhausted through a slot along the rim of the impeller. A shroud with radial fins may be positioned about the impeller.

Abstract: An apparatus for introducing gas, e.g. atmospheric oxygen, into a liquid such as waste water or sewage comprises a plurality of ribs of airfoil cross-section and forming venturi nozzles which are first constricted and then widened in the direction of liquid flow. The ribs are formed with minute passages for introducing the gas into the liquid perpendicular to the direction of liquid flow across the ribs.

Abstract: An agitator for use in flotation having a frusto-conical skirt attached to a central hub to the agitator. The agitator also having two layers of bars disposed symmetrically on the generatrices of two opposite, coaxial truncated cones mounted at their ends on circular bases, at least one base being perforated to allow passage of flotation medium, and the bases being connected by a hollow central hub of which an upper portion is adapted to receive pressurized gas and a lower portion is provided with at least one orifice for discharging the gas. The frusto-conical skirt is situated between the bars and the central hub, is coaxial with the hub and is attached at its upper end to the hub.

Abstract: In a device for dispersing gas, e.g., air into a liquid or slurry in motion, wherein the surface at which dispersing takes place has a vertical extension and thus is subjected to varying hydrostatic pressure effected by the liquid or slurry, dispersing is optimized and the performance essentially improved by compensating the varying hydrostatic pressure with a dynamic pressure caused by the liquid in motion and varying in a desired manner so that the total pressure at least at most of the dispersing surface is substantially equalized. Said compensating is effected by providing for the correct flow rate and corresponding shape of the dispersing surfaces and other possible members influencing the liquid flow. In one embodiment the dispersing surface is represented by the envelope surface of a rotor rotating about a vertical axis.

Abstract: A flotation cell of the type comprising at least one froth removal edge and a rotor and stator adapted to be immersed in the liquid to be flotated, in order to direct the surface flow in the flotation cell towards its removal edge or edges, the clearance between the rotor and the stator, as seen in the rotation direction of the rotor, widens in that rotational sector or those rotational sectors of the rotor which is or which are substantially towards the removal edge or edges and respectively converges in the other rotation sector or the intermediate rotational sectors of the rotor.

Abstract: A rotatable bell is provided having a generally downwardly diverging shape about a central vertical axis, with the outer wall surface of the bell including a circumferentially extending jet flow surface portion with a plurality of gas flow wall openings circumferentially disposed around the base part thereof. Liquid is flowed downwardly over the jet flow surface portion of the wall from the upper part to the base part thereof to provide a high shear jet flow of liquid into which gas is injected for gas-liquid contacting and bulk mixing thereof.

Abstract: A reaction vessel for continuously producing an aromatic carboxylic acid sparingly soluble in a solvent by liquid-phase oxidizing a corresponding alkyl aromatic compound with a molecular oxygen-containing gas in the presence of a lower aliphatic carboxylic acid solvent and an oxidation catalyst. The adhesion of the aromatic carboxylic acid on the inside wall of the reaction vessel at the interface between the vapor-phase portion and the liquid-phase portion is prevented by locating in the reaction vessel a means such as a porous annular pipe for spraying onto the inside wall of the reaction vessel above the level of the reaction liquid a part of a solvent-catalyst mixture supplied continuously to the reaction vessel.

Abstract: Method and apparatus for increasing the oxygen content of water for sanitizing natural waters and for purifying water, in which method oxygen or oxygen containing gas is fed into water liberated from gases dissolved therein, characterized in that gases are separated by pressure strokes on the liquid and/or vibration whereafter the desired gas, e.g. air, oxygen or oxygen containing gas, is fed into the liquid.

Abstract: An anaerobic waste treatment facility for producing methane gas or the like during anaerobic digestion of organic material. A digestor has a flexible cover therefor and apparatus associated therewith for removing evolved gases collected under the flexible cover at controlled rates. The flexible cover may assume an inflated, partially deflated, or completely deflated position. The digestor has an inlet, mixing zone, quiescent zone, clear zone, and an outlet. Liquid from the clear zone may be withdrawn and returned to pop-up rotary mixing apparatus in the mixing zone. A loading system for the digestor may comprise -- in addition to a raw sewage inlet -- a loading structure for receiving municipal garbage and the like. Apparatus is provided in the loading structure for substantially preventing the passage of non-digestible materials into the digestor, while allowing the passage of digestible materials entrained with liquid in the loading structure into the digestor.

Abstract: A vessel is provided for cultivating microorganisms. Said vessel contains a body of liquid, and a hollow rotary impeller is mounted in the vessel and has in the region of its axis of rotation a liquid inlet formed with a venturi-shaped constriction. A plurality of first gas outlets communicate with the liquid inlet in the region of the constriction so that the suction resulting from the liquid flow will pull the gas through these first outlets. A plurality of second gas outlets are located on the periphery of the impeller remote from the first outlet.

Abstract: A vessel is provided for a liquid, and a centrifugal aerating arrangement is provided in the vessel. The aerating arrangement includes a hollow substantially disc-shaped rotor mounted for rotation in the vessel and having a hub, a periphery which is formed with a plurality of outlet openings communicating with the interior of the rotor, and a Venturi-shaped inlet opening formed in an axial end of the rotor and communicating with the interior. A passage extends in part through the hub and communicates the interior with a source of gas. A drive is provided for rotating the rotor so that centrifugally created suction aspirates liquid through the inlet opening and gas through the passage, both of them entering the interior wherein they become mixed to be subsequently ejected centrifugally through the outlet openings.

Abstract: An apparatus for the treatment of liquid sewage, the sewage to be treated being aerated and mixed prior to being directed sequentially through primary and secondary settling circuits wherein primarily settleable solids and secondarily settleable solids are removed respectively. Such removed solids are then directed to a digester compartment, the secondarily nonsettleable sewage being discharged from the sewage treatment apparatus. In a preferred embodiment, a portion of the primarily and secondarily settleable solids are recirculated to the aerating and mixing area thus allowing for the floculation of the liquid sewage. In a further preferred embodiment an overflow weir is provided upstream of the sewage treatment apparatus outlet thereby providing a surge capacity for the sewage treatment apparatus.The apparatus uses a hollow propeller having a plurality of holes therein on the backface thereof; the propeller is mounted on a hollow shaft.

Abstract: An aerobic sewage treatment method and apparatus for use with a conventional septic system collection tanks having an inlet conduit (baffle) and an outlet conduit (baffle). A separate treatment vessel is mounted horizontally above the septic tank, the vessel having tangential inlet and outlet at opposite ends; the inlet connected to the output of a pump immersed in the main tank with the outlet from the treatment vessel returning to the septic tank. The vessel contains baffle means to contact floc particles and means to inject an oxygen-containing gas into the liquid as the liquid flows through the vessel. Because of the configuration of the treatment vessel inlet and outlet and baffle means in the vessel, liquid in the vessel flows tangentially under conditions of hydraulic turbulence with large shear forces generated by the baffle means to reduce the floc particle size.

Abstract: A rotating gas diffuser for shearing fine gas bubbles from the surface thereof when the diffuser is immersed in a body of liquid and rotated therein. The rotatable shaft of the diffuser may carry a plurality of main rigid structural spokes and an equal number of rigid hollow gas feed conduits positioned alternately around the shaft. A plurality of plates, each in the form of a section of an annulus with its lateral edges radially positioned with respect to the circular rotating gas diffuser, is supported either on the top or the bottom of the diffuser, or on both, near its perimeter. Each porous plate is carried by a plate holder that has a shape similar to its associated porous plates, and with those plates defines a gas plenum having an area substantially equal in extent to, but no greater than, the area of the plates.

Abstract: A fermentation vessel has a tubular guide baffle, including a tubular member extending through it. A bundle of heat-exchange tubes extends through the tubular member. An impeller is located at one end of the baffle and circulates a mixture of a gaseous and a liquid phase through the same. Heat-exchange fluid is also circulated through the baffle.

Abstract: A device for revolving a liquid has a hollow shaft for supplying gas to the liquid, and the free end of the shaft is immersed in the liquid where it carries a propeller for revolving the liquid. The propeller comprises at least one screw-shaped vane, and at least part of the vane's surface forms an acute angle with the longitudinal axis of the hollow shaft, as seen from the free end of the shaft, the vane extending along at least two thirds of the circumference of the shaft.

Abstract: An aerator for dispersing a gas in a liquid comprises an elongate tube having openings at both ends and having mounted therein one or more turbines which are free to rotate about the longitudinal axis thereof. The tube is vertically submerged in a liquid, for example in a lake or pond of water. Air or another gas is supplied to the lower end of the tube. Gas bubbles rising through the tube cause an upward flow of liquid therethrough. The turbines are rotated solely by this upward flow of gas and liquid. The turbine rotation causes the gas bubbles to be broken up into a vast number of very much smaller gas bubbles which are dispersed throughout the liquid, so that optimum gas absorption may occur. The turbines are preferably so constructed that adjacent turbines (if more than one turbine is used) rotate either at different speeds or in counter directions to thus optimize the breaking up of the gas bubbles. A method for aerating a liquid is thereby provided.

Abstract: An improved apparatus and method for mixing a second material into a first fluid material includes a container for the first fluid material, a motor driven centrifugal impeller, and a conduit having an outlet coaxial with and adjacent to the centrifugal impeller for feeding the second material into the center of the impeller. The impeller is located in the container of fluid material, and the improved apparatus includes means for directing a portion of the fluid from the container inward for mixing with the second material as it enters the center of the impeller and means for directing at least a portion of the mixture flowing from the impeller outward for dispersion in the fluid in the container. The apparatus preferably also includes means for recirculating a portion of the mixture from the impeller directly back for mixing with and imparting momentum to the first and second materials as they enter into the center of the impeller.