Abstract: A mobile soil and sludge treatment apparatus and a method of treating soil and sludge useful in a soil washing process or a biological decontamination of soils and/or sludges. In one embodiment of the invention, a plurality of tanks are mounted on a vehicular trailer for over-the-road movement and each tank includes aerator/mixers and a plurality of peripherally arranged air jets with the mixing, aeration and air jets combining to prevent settling of the solids in the slurry during the decontamination process. In a second embodiment of the invention, a single large tank is mounted on a vehicular trailer with the tank including aerator/mixers and a slurry pump for recirculating the slurry throughout the tank with the recirculating pipes terminating in jet nozzles or eductors which enhance mixing and solids suspension. In a third embodiment, the aeration/mixing is obtained by a plurality of downwardly directed air jet nozzles adjacent the bottom of the tank.

Abstract: Disclosed are pellets for use in a fluidized bed type of system to provide optimum surface configuration and maximum effective surface area per unit volume for the culture of microorganisms. The pellets are of low density, preferably plaster, having a buoyancy relative to the liquid in which they are fluidized substantially neutral or slightly positive. The pellets preferably have indentations on its surfaces to enhance the growth of microorganisms. The pellets are manufactured by either cutting discs from an extruded filament or punching discs from sheets of the appropriate material, with indentations being formed during the process.Also disclosed is an aquaculture apparatus and system in which the pellets are preferably used.

Abstract: A device for dispensing a chemical solution into a pipeline transporting a liquid under pressure irrespective of whether the liquid pressure varies between a maximum and a minimum or is subsantially constant. The volume of solution dispensed is varied at times when the liquid pressure is varying by selection of an aperture from a plurality of apertures at varying axial positions, for placing the interior of the pipeline in communication with the interior of the enclosure above the solution level, at times when the level drops axially to the selected apertures; or, at times when the liquid pressure is substantially constant, by adjustment of the amount of liquid permitted to enter the device.

Abstract: An apparatus and method for increasing gas absorptiion in a liquid includes, in a first embodiment, gas injection airfoils at an inlet of an extended vertical tube and a pump at an outlet of the tube for drawing the liquid at a rate greater than the rise rate of the gas bubbles. An outlet of the pump preferrably includes a plurality of outlet nozzles. A second embodiment for use with a liquid or slurry includes a venturi gas inlet in place of the airfoils.

Abstract: A process and any of several pump/circulators provide selective rapid mixing of influent wastewater with the mixed liquor in the channel of an oxidation ditch and thereby provide maximized use of the entire volume of the channel. The pump/circulator is disposed at the beginning of the anoxic zone and preferably receives the influent wastewater. The oxidation ditch is preferably a barrier oxidation ditch or at least a baffle oxidation ditch in order to prevent backmixing.

Abstract: A method for treating water with ozone in which a countercurrent flow of liquids is established within a treatment vessel to insure intimate contact and substantial contact time between ozone and water. The ozone and water are first pre-mixed by passing the ozone through a diffuser into a moving stream of water and the mixture is circulated in a tortuous path through a coil and discharged at the end of the diffuser coil through a number of orifices into the lower portion of the treatment vessel in a generally upwardly and outwardly direction with respect to the vertical axis of the treatment tank. Treated water suitable for bottling and storage is withdrawn from the bottom of the treatment vessel at an elevation below that of the discharge orifices to establish a countercurrent flow between the incoming and outgoing fluids.

Abstract: A wate water aeration system in which tubular diffusers are arranged with short and long diffuser assemblies alternating along the length of each air lateral submerged in the treatment basin. This arrangement provides application of air which is widely distributed in the basin and descreases the upward water velocity to increase the air bubble residence time for enhanced oxygen transfer efficiency. When plural air laterals are used, each long diffuser assembly is axially aligned with a short diffuser assembly on the adjacent air lateral. Each long diffuser can either be constructed to discharge air along its entire length or it can include an imperforate pipe section which occupies one half of the diffuser length adjacent to the air lateral.

Abstract: A gas bubble generator for mixing or promoting turbulence in a liquid medium, particularly sewage or effluent, comprising a collector for gas which collector is submerged in the medium and has an exit from which leads a pipe with a curved part between the exit and a free end of the pipe from which gas escapes as a bubble to surrounding liquid medium. The free end is spaced laterally from the exit, and curvature of the curved part is such so that there is no obstruction of the pipe by the medium, the curvature forming a circular arc of 135.degree. for example. The exit of the gas collector is preferably aligned with a gas inlet to facilitate cleaning of the pipe in situ (i.e., with the generator submerged) by insertion of a flexible rod-like cleaning tool into the gas supply line, straight through the inlet and the exit, and into the pipe.

Abstract: A hybrid chemical/biological process which is highly effective to destroy the herbicide, Atrazine, in wastewater solutions is herein disclosed. The process comprises subjecting the atrazine molecule in an aqueous carrier to ozone to produce the oxidized product, diamino-s-triazine and thereafter, metabolizing the diamine in soil having indigenous and selected microorganism capable of degrading the diamine to carbon dioxide. Also disclosed is a disposal system capable of preforming the process of the invention in a single system.

Abstract: A sewage treatment plant for use aboard ship comprises a vacuum assisted fresh water flush system delivering sewage to a collection tank. Sewage is collected from the collection tank in batches for treatment. The sewage first enters a settlement tank and is then transferred to an aeration tank. After aeration, treated sewage is then transferred out in batches. The batch processing overcomes the difficulties of operating a continuous flow arrangement on a moving platform where liquid can move back and forth, which presents difficulties in controlling the level of biological activity. A controlled amount of sewage transferred to the aeration tank is diluted with grey water. A sludge storage tank is provided and suspended solids probes are provided in the aeration and settlement tanks such that sludge is automatically withdrawn from these tanks to the storage tank to maintain the level of suspended solids within predetermined limits.

Abstract: Liquid purification apparatuses and methods; an open filtration, treatment and siphon apparatus and process; a porous mass formation apparatus and process; and a liquid-solid separation apparatus and a process using a siphon member. In one embodiment, a liquid or liquid containing mass, gel, or mud having solids is contained in or introduced into an upper vessel. The liquid and particles of undissolved solids are drawn away from the upper vessel by siphonage. Particles of solids may either settle to the bottom of the upper vessel, remain in the liquid or mass, or float to the top of the surface in the upper vessel. Particles of undissolved solids may be deposited in a siphon member of porous media as the liquid and particles of undissolved solids flow through the porous media.

Abstract: Apparatus and methods for continuous sedimentation-type separation of solids from liquids of a feed slurry in a thickener-clarifier-type tank operated by overflow removal of clarified liquid and underflow removal of a concentrated underflow slurry by using a flocculant in a zone of intense mechanical agitation provided by a rotatable impeller rotated at tip speeds of between approximately 300 to 600 feet per minute to produce relatively small, bead-like floccules directly above the concentrated underflow slurry.

Abstract: Disclosed is an apparatus and method for the continuous bioremediation of sites contaminated with a hazardous substance. The apparatus includes a subsurface pumping system, for removing the hazardous substance contained in a phase separate from groundwater, which is integrated with a means for microbiologically treating the contaminated site. The means for microbiologically treating the contaminated site preferably includes hazardous substance degrading microorganisms. In operation, a subsurface pumping system separates, either above or below-ground, a free-product phase from the contaminated groundwater. The separated free-product is stored for off-site disposal. Contaminated groundwater is fed into the microbiological treatment system for further treatment and eventual recirculation into the contaminated site.

Abstract: An individual wastewater treatment plant 1 including an aeration piping sub-system 27, 28 and an inverted, cone-shaped clarifier 13 concentrically suspended within an outer tank 10, the clarifier being supported by a support grid of standard-type PVC plastic pipe elements, including a series of four radially disposed pipe sections 21 engaging the clarifier and supporting and positioning the aeration piping system. The aeration piping is force fitted into "U" shaped slots formed in the support grid. Two embodiments for the clarifier engagement and support sub-system are disclosed, one using a series of peripherally spaced, thin slotted, inverted "T" elements 23 (FIG. 4) and the other using radial pipe sections 30 extending through the wall of the clarifier (FIG. 6), with the latter using a side-ways "U" slot 31 to hold the aeration piping and the first embodiment using inverted "U" 26 slots formed in the bottom of additional "T" elements 25 (FIG. 3).

Abstract: A waste water treatment plant of simple design and high efficiency which is particularly adapted for use in small communities is described. The plant comprises a reaction tank and an aeration tank, inlet means to admit raw waste water continuously into the reaction tank, a first airlift pump or a penstock to transfer waste water intermittently from the reaction tank to the aeration tank to displace treated waste water therefrom through an outlet, aerators to aerate the aeration tank when the first airlift pump or penstock is inoperative, a second pump for transferring sludge and waste water from the aeration tank to the reaction tank after the first airlift pump has ceased operation and before the aerator is actuated, and control means to stop the aeration in sufficient time before actuation of the first airlift pump or penstock to allow substantial settling of the sludge in the aeration tank.

Abstract: Wastewater and recycled activated sludge are homogeneously mixed in a first aeration zone by injecting an oxygen-containing gas such as air into the lower portion of the zone under conditions which produce a complete mix reaction and sufficient oxygen is supplied to meet the biological oxygen demands of the mixed liquor. The gas is introduced, preferably by a plurality of fine bubble membrane diffusers, in the form of fine bubbles having a diameter less than about 4 mm. The bubbles provide both the mixing to keep solids in suspension and the oxygen required to maintain the overall dissolved oxygen content in the first aeration zone as close to 0 as possible. The mixed liquor is sequentially contacted with an oxygen-containing gas in second and third aeration zones under conditions which produce a complete mix reaction, preferably by fine bubble membrane diffusers, clarified and a portion of the settled sludge is recycled to the first aeration zone.

Abstract: An intrachannel clarifier for an oxidation ditch includes an enclosure positioned in the flow path of the oxidation ditch. This enclosure defines a perimeter wall which surrounds an internal volume made up of an upper zone, a middle zone and a lower zone. The cross-sectional area of the internal volume increases progressively from the lower zone to the upper zone. A water inlet port introduces waste water from the flow path into the lower zone, a submerged pipe in the upper zone removes clarified water from the upper zone, and sludge is actively removed from the middle zone via a sludge removal manifold disposed in the middle zone to reduce the residence time of sludge in the middle zone while maintaining a filter blanket of sludge in the middle zone.

Abstract: An arrangement for driving out volatile impurities from a ground water with a well shaft extending to the region of the ground water to be purified, the arrangement comprises an element for producing a negative pressure in the well shaft and supplying a gas underneath a water level in the well shaft, an element for providing a plurality of capillary openings in an upper sieve wall portion of the well shaft at least in a purification region between a gas inlet and a water level in the well shaft to enhance a laminary flow of ground water with relatively high speed, the capillary openings forming a greater free throughflow surface than a remaining portion of the well shaft.

Abstract: An aerating apparatus or aerator for expelling the impurities from ground water, especially for ground water under an overpressure, in which the impurities are expelled by generating a partial vacuum in an aeration shaft in the vicinity of ground water to be purified and by feeding fresh air below the water level in the aeration shaft, the aeration shaft is closed on its upper end with a pressurized receiving chamber. The pressurized receiving chamber permits fresh air to be brought in at an air pressure balancing the ground water pressure. Moreover a vacuum generator producing the partial vacuum is located in the pressurized receiving chamber.

Abstract: A configuration of an aeration chamber for an activated-sludge treatment plant includes an elongated, hydraulic plug-flow aeration chamber with a floor having a sloped portion and a level portion. The level portion, which acts as a collection area for the activated sludge, is adjacent the air diffusers of the aeration chamber at the point of maximum turbulence within the chamber. By using the force of gravity to assist in returning the activated sludge to the point of maximum turbulence, the aeration chamber of the present invention is able to process sewage in a more efficient manner.

Abstract: Disclosed herein is a bio-filtration system that provides excellent solids removal and carbonaceous B.O.D. and ammonia nitrogen removal and which comprises in combination a tank, wedge wire panels disposed horizontally therein, a fixed film media reactor with vertical channels therein, and means for introducing effluent to be treated into said tank whereby said effluent flow upwardly through said fixed film media reactor and then through said wedge wire panels.

Abstract: The present invention is directed to an efficient aeration system for use in a pool or lagoon. The system employs a venturi nozzle structure for mixing air and water. With this nozzle, multiple air streams surround a water stream to promote effective mixing. The air water mixture is discharged into a long discharge pipe which extends the mixing time for the air/water mixture leaving the turbulent mixing zone of the nozzle. Small holes drilled in the upper wall of the discharge pipe permits smaller bubbles to escape along the pipe while larger bubbles which have not yet been broken are carried further down the pipe. Further, the discharge pipe of the present invention is made larger than the nozzle area in order to slow the flow of the air/water mixture when passing through the pipe.

Abstract: This is a water aerating unit which is particularly adapted for aerating bodies of water adjacent the shoreline and is readily transportable from one location to another. A suitable transporting vehicle is provided such as a tractor having a power take-off and hydraulic system for providing the driving power water for the propeller as well as the air blower mounted on the unit. The unit is supported on a wheeled frame by which the elevation of the lower submerged end thereof may be adjustably varied by a hydraulic system.

Abstract: A water aeration apparatus is used for aeration purposes in the water-filled areas such as dams, impounded water or reservoirs, and lakes and marshes, and includes a tubular casing and supply chamber that causes large quantities of water to be exposed to the flotation action of air supplied under pressure, thus raising the water up to the surface. The apparatus may be used for water purification, or for anti-freezing purposes particularly in cold climate regions. The apparatus includes a collective tubular casing and a multiple-partitioned or common air supply chamber below the casing, the tubular casing including a plurality of tubular air and water passages formed by dividing the interior of the casing into several longitudinal passages or by combining individual tubes together.

Abstract: A process for gas dissolution which uses a vessel, a portion wall made of ceramic material for dividing the vessel into a first chamber and a second chamber, a first inlet of the vessel for introducing a liquid into the first chamber, a second inlet of the vessel for introducing a pressurized gas into the second chamber, and a discharge port of the vessel for discharging the liquid from the first chamber.

Abstract: A filtration device is disclosed comprising an assembly of three concentric tubular members in longitudinal upright position, having a closure wall at each end, the inner and middle tubular members being perforated over substantially their entire length to permit water flow therethrough, and the outer tubular member being substantially solid over its entire length. An inlet is connected to the inner tubular member at each end, and an outlet is connected to the outer tubular member. The space between the inner tubular member and the middle tubular member is a filtration chamber containing a filtration medium. A dividing device is laterally positioned in the inner tubular member dividing it into upper and lower non-communicating portions, and a dividing device is also laterally positioned in the filtration chamber dividing it into upper and lower non-communicating filtration chambers. The filtration medium is adapted to not pass through the perforations of the inner and middle tubular members.

Abstract: A filtering system for use with fish-containing ponds and bodies of water is disclosed. More particularly, the filtering system includes chambers for harboring micro-organisms which clean organic waste from the water flowing therethrough from the pond. The chambers include by-pass conduits so that a given chamber may be taken out of service for cleaning without interrupting the flow of water through the rest of the system. Further, movable walls are provided so that several chambers contained in a single structure may be varied in number and in size according to a pond's requirements. Also included is an air manifold for use in supplying air to the micro-organisms.

Abstract: Cleaning of multi-pore diffusion elements in place with cleaning gases while submerged in liquid media by applying said cleaning gases intermittently or continuously to said diffusion elements between predetermined limits of operating pressure and flow through flow regulation means and plenums for the respective diffusion elements.

Abstract: A solids excluding subsurface fixed liquid decanter is used primarily to decant the settled liquid above the decanter. The decanter has no moving parts and will discharge this liquid at a constant flow rate regardless of the liquid head pressure above the decanter over the time of decant. The decanter is designed to exclude solids and liquid from entering the confines of the device during the fill and mixing cycles of an SBR waste treatment process. During the aeration cycle, air is directed into a bell or hood of the decanter to replace any absorption or leakage in vent piping of the decanter. The decanter also has a mechanism for skimming the surface of the liquid volume for removing floating solids that are undesirable to the process.

Abstract: The outgoing gas or waste water is conveyed through a gas-liquid contact apparatus in which biological purification takes place. A bubble plate-type column (2) is used as gas-liquid contact apparatus. The biomass is distributed over the plates (3) in the form of an aqueous suspension with a layer height corresponding to a liquid content per plate greater than 0.07 m.sup.3 /m.sup.2, preferably greater than 0.15 m.sup.3 /m.sup.2 of column cross-section. During the biological purification of gas, the gas to be purified is supplied at the lower end of the bubble plate-type column (2). It then flows through the plates (3) and issues again as purified gas at the top of the plate column (2). When the plate column is used for purifying waste water, the waste water to be purified is conveyed from top to bottom through the plate column (2) and is traversed by air, oxygen or oxygen-containing gas.

Abstract: An improved wastewater aeration and mixed liquor pumping arrangement for an orbital-type actuated sludge purification method includes the addition of a radial flow impeller on a shaft extension below the normal surface aerator. Both the combined radial flow impeller and surface aerator are positioned with respect to an end of a partition wall forming the flow channels of the orbital system such that both the impeller and the aerator pump the mixed liquor in the same direction, so that the mixed liquor is moved at a sufficient velocity through and around the various channels and returned. The radial flow impeller is positioned adjacent to the bottom of the orbital channel and enhances the propulsion of the mixed liquor along the bottom of the channel thus permitting deeper channels with attendant concrete and land area savings in constructing the system.

Abstract: A method and apparatus for degrading biodegradable waste through bioaugmentation, the waste treatment apparatus comprises a waste treatment tank including a multistage waste treatment section and a waste settling section, the multistage waste treatment section comprises a plurality of waste treatment chambers, a blending device to emulsify and aerate the waste in at least one waste treatment chamber, a transport system to selectively supply bacteria to the multistage waste treatment section, to selectively transfer waste and bacteria to and from the multistage waste treatment section and to selectively transport sludge to and from the waste treatment tank and a fluid transfer port formed between the final waste treatment chamber and the waste settling section to transfer reduced waste to the waste settling section, the method comprises reducing the biodegradable waste treatment section aerating and emulsifying the bacteria and waste and selectively circulating the bacteria and waste between the waste treatmen

Abstract: An aquarium filtration system using airlift to circulate water within the living area to display aquatic organisms, water rising up through the bottom gravel, the gravel providing biological filtration. The living area of the acquarium is free from mechanical obstructions and rising air bubbles. A relatively inexpensive air pump generates the air lift, for circulating water within the living area. Water is removed at the water's surface and thereafter mechanically and chemically filtrated. A protein skimmer device is provided as an integral part of the air lift and mechanical filtration chamber to remove dissolved organic and inorganic compounds.

Abstract: A sewage or waste material treatment plant or apparatus includes adjacent aeration and clarifier chambers with an intermediate internal wall having a bottom opening normally providing the sole communication between the chambers. A deflector member in the upper portion of the aeration chamber in the path of incoming material, a deflector surface on the lower portion of the internal wall, together with a diffuser assembly, provides a substantially circular flow of fluid and solids to promote maximum suspension of solids and their oxidative or bacteriological breakdown. A specially configured deflector on the lower portion of the internal wall further directs the moving fluid in the aeration chamber so as to promote the circular movement of material therein and also to enhance the return of settled floc from the adjacent clarifier chamber back into the circulating stream in the aeration chamber.

Abstract: A treatment system for water or wastewater is provided, comprising a tank having a substantially circular continuous sidewall and a bottom; a mixing device, for mixing and circulating liquid within the tank, positioned within the tank; and an intra-channel clarifier, positioned within the tank between the center of the tank and the sidewall such that the clarifier will be partially submerged when the tank contains liquid, the clarifier including a bow, a stern, side walls, an entry opening and at least one discharge port in the bottom, the clarifier having an elongated shape such that the side walls are generally parallel to the sidewall of the tank.

Abstract: A method and apparatus according to the invention provide for the use of ultraviolet radiation in combination with a magnetic field, whereby improved purification of the aqueous medium is achieved.

Abstract: A waste water and sewage treatment system for use in a facultative aeration-sedimentation basin or lagoon includes a submerged water pump mounted in a well in water communication with the basin. This pump supplies water under pressure to a water header on which a plurality of water jets are mounted in such a manner as to create the forced water circulation inside the basin. Each water jet incorporates an air-sucking venturi to oxygenate the waste water or sewage. Valves are provided in the well for disconnecting the water pump from the water header and then connecting it to a sludge collecting duct extending from the well over a given distance into the basin in such a manner as to drain off the accumulated sludge at the bottom of the basin through the sludge collecting duct and drain-out through a sludge disposal pipe. The system is particularly interesting in that it makes use of the same pump to aerate the waste water or sewage and drain-off the accumulated sludge.

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: A method and apparatus for the treatment of waste water. The method comprises a primary sedimentation stage, an activation stage comprising high, medium and then low loading rate oxidation stages, a filtering stage and a clarification stage. All of these stages are performed in a single flat-bottomed parallelepipedal basin. The water treatment apparatus comprises a sludge recirculator (23, 24), an aerator (22, 25), a skirt (26), a filter (29) and a horizontal laminar flow clarifier (27). The clarifier is made up of a succession of inclined baffles (27a) joined together in pairs at their upper and lower edges. Sludge aspirator pipes (28) are provided adjacent the bottoms of the inclined baffles.

Abstract: A device for aerating water. The device includes a rigid support member, and a finely slitted plate of elastomeric material that is disposed on the support member. To prevent the plate from bulging too greatly, and to provide a uniform discharge of air over the entire plate, the thickness of the central portion of the plate is greater than the thickness of the rim portion of the plate, with the thickness of the plate preferably diminishing gradually in the direction toward the rim of the plate.

Abstract: A plurality of aerators are arranged in a preselected pattern on the floor of a basin or lagoon containing waste water. Compressed air is supplied to the aerators by aeration pipes anchored by hanger brackets to the floor of the basin. Each aerator has a porous diffuser plate through which the air is passed and released into the waste water in the form of ultra fine air bubbles less than 60 microns in diameters. The air bubbles are generated in an intense manner with a high rate of air flow to increase the mixing action and liquid circulation pattern, and to create turbulent boils at the surface which provide surface aeration from atmospheric air and re-entrainment of air from eddy current circulation.

Abstract: An apparatus for the treatment of wastewater from relatively small structures such as single family residences, dwellings and the like includes first and second vessels connected by a flow line, the first vessel including a wastewater inlet and the second vessel including an outlet for the discharge of clarified water. A transverse baffle divides the second vessel into aeration and clarifier sections, the clarifier section including a transversely mounted inclined plate which prevents the accumulation of solid material in the clarified section and redirects the solid material back into the aeration section. A multiple angle discharge piping arrangement prevents clarified liquid from discharging the apparatus until it has made at least two right angle turns before reaching the discharge piping of the unit.

Abstract: A water aeration apparatus is used for aeration purposes in the water-filled areas such as dams, impounded water or reservoirs, and lakes and marshes, and includes a tubular casing and supply chamber that causes large quantities of water to be exposed to the flotation action of air supplies under pressure, thus raising the water up to the surface. The apparatus may be used for water purification, or for anti-freezing purposes particularly in cold climate regions. The apparatus includes a collective tubular casing and a multiple-partitioned or common air supply chamber below the casing, the tubular casing including a plurality of tubular air and water passages formed by dividing the interior of the casing into several longitudinal passages by combining individual tubes together.

Abstract: The present invention relates to a method and equipment for carrying out the degradation of various organic products or waste in an anaerobic medium. The equipment comprises a plurality of ducts for reinjecting biogas into a fermentation vat sidewise spaced from each other and disposed at least in the major part of the vat, the duct being fed with biogas individually or in groups through independent valves so as to subdivide the fermentation vat into sectors independently fed with biogas. Preferably, a container is provided for storing biogas under pressure. These features lead to a simplification of the equipment and a decrease in the manufacturing costs.

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: Apparatus for treating waste water by the solids contact aerobic biological treatment process comprises a clarifier and a reaction basin in liquid communication with one another. In one embodiment, the reaction basin has an aerator which also circulates liquid through the clarifier by way of pipes arranged to collect liquid from the surface of the reaction basin and deliver it to a location adjacent a back wall of the clarifier. The clarifier has a bottom wall which slopes towards the reaction basin. Sludge particles in the liquid settle out in the clarifier and liquid discharged from the pipes flushes the settled biological sludge back into the aeration section of the reaction basin. In another embodiment the clarifier and reaction basin together form an oxidation ditch defining a closed loop. An aeration device continuously circulates liquid around the loop and through the clarifier.

Abstract: Apparatus for use in removing waste from a fish culture system including a tank through which water from the system may be circulated, filters mounted in upright and spaced apart relation across the tank so that the water circulates successively through them, and tubes for injecting air into the water on the upstream side of each filter.

Abstract: An oscillating propeller type aerator apparatus for more efficiently aerating a liquid is disclosed. The oscillating propeller type aerator apparatus for aerating a substance according to the present invention includes a propeller type aerator and an oscillating support system. The aerator includes a tube, a propeller, and means for rotating the propeller. The oscillating support system supports the aerator with the tube and propeller at an acute angle below the surface of the substance to be aerated. The support system includes a mechanism for oscillating the tube and propeller through an angle about an axis transverse to the surface of the substance to be aerated in order to disperse over an arc related to said oscillating angle, air injected through said tube into the substance.

Abstract: A continuously flowing fluid is processed by being fed to the top of a hydraulic downdraft column (17) which is of a height such that the pressure at the bottom thereof will approximately be at the pressure necessary to create supercritical water conditions. The fluid is conducted to the bottom of the column (17) and received in a reaction chamber (21) in which the majority of the fluid is recirculated around an annular baffle plate (24). The material in the reaction chamber (21) is heated to a temperature above that necessary to create supercritical water conditions by an independent reaction taking place in a heating chamber (32). The result is that the fluid will undergo chemical reactions at the supercritical temperature and pressure range and will be of a lower specific gravity than the unprocessed fluid.

Abstract: A strainer for a liquid sucking device and adapted to be attached to the end of a flexible liquid sucking tube of the device. The strainer has an outlet tube adapted to be connected to the flexible liquid sucking tube of the device, a spherical shell integral with the outlet tube, a strainer element attached to the outer surface of the spherical shell and a weight accommodated by the internal cavity of the spherical shell.