Abstract: Improvements are made to a system in which force is applied to aeration units from only one side of a basin. Part of such force is vector transferred from one end of a beam of the aeration unit to the other end of the beam to move both ends of the beam. The beam supports pipes of the aeration unit. A force transfer module includes one force transfer strand held in a force transfer path between fixed opposite ends of the strand. The force transfer path extends in part along the beam, which is placed in compression. Motion of the one end of the beam resulting from the force is transferred by the single force transfer strand to the opposite end of the beam so that both ends of the beam move relative to the basin under the action of the force.

Abstract: The outer surfaces of hollow fiber membranes in a skein, or a bank or cassette of stacked skeins, are kept essentially free of solids by maintaining a substantially uniform flow of a stream of coarse bubbles through each of plural orifices in an aerator disposed beneath the fibers. Aerators for skeins used in microfiltration of wastewater in a tank are periodically flushed by injecting flushing air into permeate returned to the tank over a short period. The air is injected into returning permeate for less than 1 minute, preferably less than 20 sec so as to produce discrete masses of water which are flowed laterally through the body of the aerator, cleaning its walls and maintaining the orifices essentially free from plugging.

Abstract: A gas diffuser assembly adapted for location in a volume of liquid or semiliquid material for dispersing minute bubbles of gas into the liquid. The assembly includes a housing formed of dense impermeable ceramic material and which defines an upwardly facing recess. A fitting formed of an inert material is located in the floor of the recess for connection to a gas supply tube. A diffuser element formed of porous ceramic material is secured to the housing over the recess to define an enclosed gas chamber. The diffuser disk and the housing are adhered together with a suitable cement.

Abstract: A device for the treatment of polluted water having a primary chamber, a principal distribution chamber with an inlet connected to a source of polluted water, a secondary distribution chamber connected to a supply of polluted water, an air inlet orifice formed in the primary chamber for allowing air to pass into the primary chamber, a venturi connected in fluid communication with the primary chamber, and a drain pipe connected to the venturi. The principal distribution chamber has a spray nozzle connected thereto and positioned in the primary chamber. The secondary distribution chamber has a high-speed nozzle positioned within the primary chamber and directed toward the venturi. The venturi is a cone-shaped member with a wide end adjacent to the primary chamber and a narrow end adjacent to the drain pipe. The venturi is positioned below the primary chamber so as to accelerate a flow of an air/water mixture passing from the primary chamber.

Abstract: A wastewater treatment plant for removal of organic matter, suspended solids and other pollutants comprising a pre-treatment chamber, a biofilm-aeration chamber and a settling chamber. Biofilm grows on biofilm support structure which is stationary and submerged in the mixed liquor of the biofilm aeration chamber. The combination of submerged or surface aeration and suspended solids particle size reduction occurs thereby creating a sufficient fluid flow within the biofilm aeration chamber. This combination of sufficient fluid flow, and reduced size suspended organic particles results in the efficient digestion of organic matter and pollutants by the biofilm growing on the biofilm support structure submerged in the biofilm aeration chamber. This results in a vastly more effective digestive process than conventional processes producing no sludge. Further, resulting treated effluent has a high dissolved oxygen content and low BOD and SS.

Abstract: A system for removing hazardous contaminants such as radon gas and volatile synthetic organic chemicals from domestic water supplies includes a perforated, horizontally-oriented tray which is baffled to define a curved (e.g., serpentine, spiral) liquid flow path. Contaminated water is distributed upon a portion of the tray and flows as directed by the baffles to a downcomer and into a storage tank. Air is blown into the storage tank, which is located below the perforated tray, and up through the perforations. The forced air causes the water flowing across the tray to froth, and evaporates the contaminants out of the frothing water. The forced air, carrying the volatilized contaminants, is then vented outside the home.

Abstract: A wastewater aeration system in which the volume of wastewater is divided into a plurality of different zones which are aerated sequentially one at a time with the full capacity of the blower supply sized for oxygenation needs. In the case where the oxygenation needs ar significant, the number is obtained by dividing the aeration rate required for mixing by the aeration rate required for oxygenation and rounding upwardly to the nearest integer. The blower capacity should continuously deliver the oxygenation rate to assure adequate aeration for both oxygenation and mixing while minimizing energy consumption. The air supply pipe network includes a header supply pipe for each zone and a valve for each header supply pipe which is automatically controlled by a programmable programmer. In the case where mixing only is required, the number of zones is limited by practicalities in order to prevent undue settling.

Abstract: An aeration device is immersed in an aeration-sedimentation basin for oxygenating the water contained therein. The aeration device comprises a vertical, hollow aeration column with a lower inlet and an upper outlet. A pipe supplied with pressurized air has an orifice to produce in the column an upward jet of air. A skirt surrounds the lower portion of the column including the inlet, which skirt has a closed, lower end but an open, upper end above the level of the solid accumulations in the basin. Water substantially free from solid accumulations is therefore pumped by the air jet through the open, upper end of the skirt and the water inlet, the pumped water flowing through the column from the inlet to the outlet while being oxygenated by the air jet, and the so oxygenated water being returned in the basin through the outlet.

Abstract: To increase the efficiency of the gas transfer in an element for the transfer of gas into liquids, in particular, for the transfer of oxygen in sewage treatment plants, with a porous gas transfer member into which gas is introduced via a feeder line and after passage through a porous gas transfer member is given off in the form of gas bubbles into the liquid surrounding the gas transfer member, it is proposed that the gas transfer member be in the form of a circular-cylindrical pipe consisting of porous material which is closed at both end faces by an end section made of porous material, and that the pipe be horizontally and sealingly positioned on a gas feeder line which opens into the pipe on the lower side of the pipe halfway between the two end faces.

Abstract: An improved fine bubble diffuser and diffuser system is provided. The diffuser includes a filtered blow-down tube for containing an internal gas pressure within the diffuser and allowing water to be removed from the system and further includes a filter disposed between the blow-down tube and the diffuser for filtering solids from water entering the diffuser.

Abstract: A process for the aeration of off-water or the like media in an aeration tank with the aid of an aeration face arranged below the water surface as well as an aeration device for carrying out this process in practice are described. The device comprises a rigid, self-supporting supporting body provided with throughholes or being of porous material and covered with an elastic diaphragm; air is supplied to the supporting face of the body at the center of gravity or a gravity line thereof into a deflecting region and from there to the periphery of the body which is slightly raised vis-a-vis the central region of the body, from where the air escapes with decreasing pressure into the water to be aerated. The aeration face can be adapted to be swivelled, and the cross-sectional area of the supporting body can be of pyramid, wedge, circular or frustoconical configuration or it can be vaulted in a concave or convex manner.

Abstract: An improved gas diffuser tube assembly, particularly for diffusing bubbles of oxygen gas into liquid sewage during treatment thereof, is provided. The assembly is characterized by a construction which creates substantially the smallest bubbles that would be operationally practical and which satisfactorily prevents back flow of liquid into the diffuser assembly by including the following. An inner support tube has apertures extending radially therethrough in a bottom portion thereof for passing gas from the inside to the outside thereof. A flexible membrane surrounds the support tube and has a plurality of minute punctures extending therethrough and located in an upper section thereof for receiving the gas which passes between the support tube and the membrane and discharging the gas under pressure out of the membrane sheath in the form of fine streams of tiny bubbles of the gas.

Abstract: Gas diffusion elements, formed of a body of solid particles which have been shaped, pressed and rendered coherent by bonding or sintering in a compacted form having pores, are disclosed. Said elements include a peripheral, annular zone of relatively small proportions having lesser permeability, greater density or lesser height than at least a portion of the remainder of the element. In accordance with the invention, a boundary zone is provided adjacent to and inwardly of the peripheral zone, in which boundary zone there is a progressive increase, continuous or step-wise, in the apparent volumetric compression ratio of the element, in the direction of the pheripheral zone, or towards a vertical surface which is near the periphery of the element. Such element may provide improved gas, e.g. oxygen transfer efficiency and therefore holds promise of improving the efficiency and economics of gas transfer processes, such as for instance treatment of sewage or other waste water with air, oxygen and/or ozone.

Abstract: Diffusers on the bottom of a submerged header each include coarse bubble orifices which discharge a stream of air to form a bubble or film on the underside of a horizontal spreader at the edges of which the bubble is sheared by flowing water into multitudinous tiny bubblets rising in the surrounding liquid as a cloud. A second horizontal spreader, slightly above the first, has a similar action, shearing into fine bubblets any larger bubbles which escape from the first spreader to the second. Edges are staggered to supply air to different parts of the water flow. The rising bubblets set up a conventional rolling action in the body of liquid. It is this rolling action which produces the flow of water past the spreaders to shear the bubbles at their edges. A snap-in screw-tightened band secures each diffuser to the header.

Abstract: There is provided a simple gas diffusing apparatus composed of a top member having gas permeable perforations, a bottom member including a plurality of larger openings for removal of solid and semi-solid accretions, a gas inlet nipple for introduction of a gas, e.g. air, into the cavity formed by the assembly of the top and bottom members, a valve, a valve seat disposed on the inner surface of the bottom member, and stop means for the valve for confining the valve between a seated position and an unseated position.

Abstract: An improved fine bubble diffuser and diffuser system is provided. The diffuser includes a filtered blow-down tube for containing an internal gas pressure within the diffuser and allowing water to be removed from the system and further includes a filter disposed between the blow-down tube and the diffuser for filtering solids from water entering the diffuser.