Abstract: A user-friendly centrifugal flotation cell with a rotating drum, is provided for use in an efficient separation process to rapidly recover greater quantities of valuable fine particles. In the process, a slurry of fine particles is injected with air bubbles and moved downwardly through a stationary downfeeder to a centrifuge comprising a rotating flotation cell. The aerated slurry is centrifugally separated into a waste stream of non-floating gangue material and a particulate-enriched froth comprising air bubbles carrying a substantial amount of the valuable fine particles. The froth is processed by froth flotation in a froth flotation chamber.

Abstract: The method and apparatus mixes two immiscible liquids A and O to form a dispersion and then pre-separates the dispersion into two fractions (A+o) and (O+a) in a spout. These two fractions are fed separately into a decanter with two separate compartments which continue to maintain the two fractions as separate. Within the two separate compartments the two fractions are further separated into two flows, A, O, a, and o, such that four flows exit the decanter.

Abstract: A method for rupturing microalgae in an aqueous suspension is disclosed. In one embodiment the aqueous suspension is passed through a constriction into a liquid phase at a pressure sufficient to rupture the cells by circulating the aqueous suspension through a constriction in a pump loop at a pressure and a percent recycle sufficient to rupture the cells. Cells of the alga Dunaliella salina can be ruptured by the method of the invention to promote froth flotation and mechanical filtration of the cells for recovery of mixed carotenoids.

Abstract: An apparatus for producing highly pressurized air-saturated water intended preferably for dispersion in flotation plants, has, preferably, an upstanding cylindrical pressure vessel (21) which, in operation, is filled partially to a controlled level with pressurized water flowing through an opening in the bottom part of the vessel, and partially by continuously delivered pressurized air, wherein the air is dissolved in the water during its passage through the pressure vessel (21). Pressurized water is delivered to the apparatus in the upper end of the pressure vessel (21) through a spray element (24) or the like to effectively break up the water flow. The spray element is arranged so that at least part of the water flow is sprayed on to the inner wall surfaces of the vessel (21) which, in operation, surround the air-filled part and together with this part produce a curtain of water which substantially covers the inner wall surfaces.

Abstract: A process for recovering protein, fatty and water components from a float material produced by a waste water treatment system, wherein the protein and fatty components can be further processed for inclusion in various products, such as animal feed. The recovered water component can also be further processed before discharged into a sewer system.

Abstract: This invention relates to a device for the separation of oil from water containing impurities in industries, waste plants, ships or the like.

Abstract: An apparatus and method for removing contaminants from waste water directs the waste water through a first magnetic field. An ionic polymer is introduced into the waste water after the waste water passes through the first magnetic field, whereby at least some contaminants flocculate. Flocculated contaminants are separated from the waste water so as to form a waste water effluent. An oxidizing agent is introduced into the waste water effluent and the waste water and the oxidizing agent are directed through a second magnetic. The waste water is directed through a weir into a trough open to the atmosphere. Air is injected into the trough so that at least one gas within the waste water combines with the air injected into the waste water. The combined air and gas floats to the surface of the waste water and is expelled into the atmosphere. Foam is removed from the waste water in the trough.

Abstract: An apparatus and method for treating waste water to generate clarified water for reuse in industrial processes which includes the steps of adding agents to the waste stream to generate floccules, aerating the waste stream to cause a portion of the floccules to float, decanting floating floccules and lighter than water immiscible pollutants from the top surface of the waste stream, directing the waste stream through an incline clarifier so as to permit heavier than water floccules to form sludge in a bottom region of the clarifier. Sludge and decanted pollutants are sent to a bioremediation tank where hydrocarbons are decomposed and the remaining sludge is dewatered and compacted to a solid condition for disposal in a public waste facility. The clarified water is transferred to a steam generator or pressurized water delivery system for reuse. The invention is particularly useful for equipment cleaning operations such as in truckyards or airports.

Abstract: A process and system are disclosed for recovering mixed carotenoids from the alga Dunaliella salina. The harvested cells are ruptured, typically by circulating the algal suspension at high pressure through a pump loop. The cells can then be dewatered by absorptive bubble separation techniques, including a froth floatation circuit that has a roughing zone and a concentrating zone. If further concentration is desired, the algal concentrate can be mechanically filtered in a cross flow microfiltration unit in the absence of flocculating agents with substantially no loss of carotenoids in the permeate. Various methods for extracting mixed carotenoids and other components from the algae are disclosed, including dense gas extraction, and extractions with natural and synthetic flavorants, and edible oils.

Abstract: A method for on line recovery of oil from an oil in water emulsion spilled in water includes the steps of: obtaining a stream of recovered material including an oil in water emulsion and water; inducing a gas into the stream and applying shear so as to provide a mixture wherein oil from the oil in water emulsion is adhered to bubbles of the gas; passing the mixture to a flotation compartment for allowing the oil adhered to the bubbles to rise to a surface of the mixture; and removing the oil from the surface of the mixture.

Abstract: The invention relates to a method and a device for purifying water used for forming a water curtain of a wet spray wall in paint spray and/or glue processing booths, wet dust removal plants and the like. The water to be purified is caught in a receptacle (1) and the water is sucked out under the surface of the water present in said receptacle (1), mixed with air and introduced into a basin (14) at the bottom side of said basin (14). The water mixed with air is introduced into a basin (14) which widens in upward direction, and contaminations floating on the surface of the water present in said basin (14) are pushed towards an outlet disposed near one side of said basin (14) by means of a pusher, whilst the water flows out on the opposite side of the basin via an overflow. A few perforated plates disposed one above the other are provided in the basin (14) whose sectional area gradually increases in upward direction.

Abstract: A method for on line recovery of oil from an oil in water emulsion spilled in water includes the steps of: obtaining a stream of recovered material including an oil in water emulsion and water; injecting a gas into the stream and applying shear so as to provide an injected mixture wherein oil from the oil in water emulsion is adhered to bubbles of the gas; passing the injected mixture to a flotation compartment for allowing the oil adhered to the bubbles to rise to a surface of the injected mixture; and removing the oil from the surface of the injected mixture.

Abstract: Process and apparatus for the separation of solid matter via flotation. The flotation process for the separation of solid matter from a suspension takes place via the utilization of centrifugal forces wherein the suspension is brought into rotation in a separating zone so that the floated components are particularly effectively routed to and concentrated at the center of the separating space, whereby, when viewed axially, floated components and the remaining portion of the suspension is guided in the same direction and out of the separating zone, with the avoidance of vortexes in the flow stream achieving particularly favorable separation effects. In addition, several apparatuses, for carrying out the process, are also set forth.

Abstract: A process for dewatering an aqueous suspension of microalgae is disclosed in which the aqueous suspension of the algae is introduced into a bubble column or a modified bubble column for generating a froth of bubbles and adsorbed algal cells that can be separated from the aqueous suspension. In one advantageous embodiment, the bubble column is a multi-stage loop-flow flotation column that has three loop-flow zones, each of which is defined by a draft tube concentrically mounted in the column to divide each loop-flow zone into a riser and the downcomer. Fine bubbles of gas and brine are in cocurrent upward flow in the riser and in cocurrent downward flow the downcomer. A higher gas holdup is promoted in the riser than in the downcomer, thereby circulating the brine in loop-flow upwardly through the riser and downwardly through the downcomer. Liquid communication between adjacent loop-flow zones is substantially eliminated. A froth enriched in algae is generated that can be separated from the aqueous suspension.

Abstract: Method and equipment for purification of a liquid, where the liquid is polluted by other liquids or solid material, e.g. removing oil from oil contamined water, comprising a flocculation device (2) and a flotation device (8). The method comprises adding one or more chemicals to the liquid in a flocculation device that comprises one or more pipe loops (2) with built-in agitators (3, 20, 21) providing turbulence and plug-type flow through the loop. Thereupon purified liquid and pollutants are separated in the flotation device or in a sedimentation device (8). The equipment according to the invention comprises a pipe loop (2), provided with built-in agitator(s) (3, 20, 21), connected to the flotation device (8).

Abstract: This invention relates to the design and operation of paired subsurface flow constructed wetlands in which significant improvements in wastewater treatment are possible. These improvements are brought about by coupling paired subsurface flow wetlands and using reciprocation, whereby adjacent cells are sequentially and recurrently drained and filled using either gravity, mechanical pumps, U-tube air-lifts and/or a combination thereof. This fill and drain technique turns the entire wetland area into a biological reactor, complete with anoxic, anaerobic and aerobic environments. The frequency, depth and duration of the fill and drain cycle can be adjusted to control redox conditions for specific biologically mediated reactions including, but not limited to, nitrification, denitrification, sulfate reduction, and methanogenesis. Emissions of noxious gases such as hydrogen sulfide and mentane can be minimized.

Abstract: A compact dissolved-air-flotation (DAF) clarifier and clarification process utilize three zones for clarification which operate in sequence in a single clarifier. Raw water with suspended solids enters a flocculator at the center of an annular tank where microscopic air bubbles introduced to the inflow float flocked contaminants to form a floating sludge layer. A first clarification, calming and degassing occur here. The water then flows radially outwardly into the tank where further quiet clarification occurs. A third level of clarification occurs in a lower portion of the tank, specifically, in a set of plate-like lamellae, radial and conical, which form inclined channels where a final clarification occurs. The bottom wall of the tank has a set of apertures which allow a gravity flow of clarified water through a layer of pressurized gas to an underlying collection compartment.

Abstract: Hydrophobic material is selectively separated from an aqueous feed by forming gas bubbles in a flow of the feed, forming hydrophobic material/gas bubbles aggregates by motionless mixing and separating the aggregates as a froth by use of centrifugal action.

Abstract: A wastewater treatment method involving mixing of the wastewater with an activated sludge and water that has been supersaturated with air under high pressure is described. After the pressure is reduced two processes are carried out which are biological oxidation of pollutants by activated sludge and flotation of suspended solids. A portion of the treated water is saturated with air and returned to the beginning of the process. The waste activated sludge is removed along with some floated and biologically non-oxidated pollutant particles.

Abstract: A compact dissolved-air-flotation (DAF) clarifier and clarification process utilize three zones for clarification which operate in sequence in a single clarifier. Raw water with suspended solids enters a flocculator at the center of an annular tank where microscopic air bubbles introduced to the inflow float flocked contaminants to form a floating sludge layer. A first clarification, calming and degassing occur here. The water then flows radially outwardly into the tank where further quiet clarification occurs. A third level of clarification occurs in a lower portion of the tank, specifically, in a set of plate-like lamellae, radial and conical, which form inclined channels where a final clarification occurs. The bottom wall of the tank has a set of apertures which allow a gravity flow of clarified water through a layer of pressurized gas to an underlying collection compartment.

Abstract: Flotation apparatus (10) for removing finely divided bodies of an insoluble substance dispersed in an aqueous medium, such as oil and solids dispersed in water, comprises a vertical flotation column (12) having a feed inlet (14) and an outlet (22) for the aqueous medium, a sparging system (16) for generating gas bubbles rising upwardly in the aqueous medium to capture and raise the finely divided bodies of the insoluble substance to the surface of the aqueous medium in the column to form a layer (31) of the insoluble substance on the surface of the aqueous medium, a launder (18) for receiving an overflow of the insoluble substance and an outlet (20) for the insoluble substance in the launder. The apparatus (10) can be used in both countercurrent and co-current fashion. In a particular embodiment, the apparatus includes a mechanism for the intermittent dumping of the layer (31) of insoluble substance from the column (12).

Abstract: Water to be treated is introduced into a basin having a closed bottom and an outer wall. A stationary diffusor is located at the bottom at a position spaced from the outer wall and produces air bubbles of varying size acting to lift water impurities toward the surface of the water and to circulate the water in the basin as a first stream flowing vertically upwardly from the diffusor, horizontally outwardly toward the outer wall, vertically downwardly toward the bottom and horizontally along the bottom back to the diffusor. A second stream is caused to circulate circumferentially in the basin. The first and second circulating streams cooperate to cause foam and slurry formed on the surface to concentrate in an outer peripheral flow path from which the foam and slurry are removed.

Abstract: A method for cleaning unwanted materials from a swimming pool having water and a water recirculation filtration system wherein the water circulates through the recirculation filtration system. The method comprises the steps of placing microscopic air bubbles having a size of in the range of from abut 0.1 mm to about 0.001 mm into water circulating through the water recirculation filtration system, circulating the microscopic air bubbles into the water of the swimming pool for a period of time sufficient to precipitate onto unwanted materials in the pool, allowing the materials to float to the top of the surface of the water, and removing the unwanted materials from the surface of the pool. An apparatus for accomplishing the method is also disclosed.

Abstract: An apparatus and method for removing contaminants from waste water directs the waste water through a first magnetic field. An ionic polymer is introduced into the waste water after the waste water passes through the first magnetic field, whereby at least some contaminants flocculate. Flocculated contaminants are separated from the waste water so as to form a waste water effluent. An oxidizing agent is introduced into the waste water effluent and the waste water and the oxidizing agent are directed through a second magnetic. The waste water is directed through a weir into a trough open to the atmosphere. Air is injected into the trough so that at least one gas within the waste water combines with the air injected into the waste water. The combined air and gas floats to the surface of the waste water and is expelled into the atmosphere. Foam is removed from the waste water in the trough.

Abstract: An apparatus and method for removing contaminants from waste water directs the waste water through a first magnetic field. An ionic polymer is introduced into the waste water after the waste water passes through the first magnetic field, whereby at least some contaminants flocculate. Flocculated contaminants are separated from the waste water so as to form a waste water effluent. An oxidizing agent is introduced into the waste water effluent and the waste water and the oxidizing agent are directed through a second magnetic. The waste water is directed through a weir into a trough open to the atmosphere. Air is injected into the trough so that at least one gas within the waste water combines with the air injected into the waste water. The combined air and gas floats to the surface of the waste water and is expelled into the atmosphere. Foam is removed from the waste water in the trough.

Abstract: Methods are disclosed for dewatering an aqueous suspension of microalgae, especially Dunaliella salina, with a Jameson cell. The algal cells are ruptured sufficiently to promote froth flotation of the cells from the suspension. The algal suspension is introduced into the top of the Jameson cell downcomer and passed through an orifice plate therein to generate a free liquid jet of the suspension. The jet is plunged downwardly through a gas and the gas is transported with the jet through a gas and liquid interface into the algal suspension. The momentum of the jet is dissipated, which disperses the gas into fine bubbles. The fine bubbles are intimately contacted with the aqueous suspension in cocurrent downward flow in a collection zone to absorb the algal bodies onto the surfaces of the bubbles. A froth of bubble and algal agglomerates is formed and collapsed to obtain a dewatered algal concentrate.

Abstract: A dissolved gas flotation system for treatment of wastewater or contaminated water and having an improved flow pattern wherein the subnatant discharge outlet and the inlet distribution structures are located adjacent one another. Such a structural design takes advantage of the fluid flow patterns within the tank to maximize the effect of the air bubbles in separating solids from the fluid.

Abstract: A flotation apparatus including: an elongate vertical riser (142) in which a cocurrent flow of gas/slurry liquid mixture rises upwards to a discharge mouth at its top end; an aeration unit (140) provided at a lower end of the riser; a separation unit (150) provided at the top end of the riser; and wherein the height of the riser is selected to produce substantially turbulence free flow in which a high gas lift occurs in the riser such that a pressure drop between the liquid inlet and the discharge outlet of the aeration unit is sufficient to produce gas particle dispersion and recirculation of the slurry liquid through the flotation apparatus.

Abstract: A method for treating a liquid flow to be cleaned passing through a flow line into a flotation plant including passing a portion of the liquid flow to be cleaned from the flow line along a first branch line into a pump. The suction capacity of the pump is regulated to draw in a direct flow of gas so that the pump sucks the gas as a direct flow. The drawn-in direct flow of gas is then mixed with the liquid flow in the pump and passed along a discharge pipe of the pump into a mixing part wherein the discharge pipe ends in a pressure release. The remaining portion of the liquid flow to be cleaned from the flow line is then passed along a second branch line into the mixing part. A liquid flow is discharged from the pressure release, the liquid flow including gas bubbles containing dissolved gas.

Abstract: The subject invention concerns a process for removing proteins from aquarium waters. The protein is efficiently removed from the aquarium water (salt or fresh) by contacting the water with a vortex air/water bubble pattern. The protein attaches to the bubbles and the bubbles are then skimmed from the aquarium water.

Abstract: A dissolved air flotation (DAF) system and method for gas-liquid contacting operations. A mixture of untreated liquid and liquid-saturated with dissolved air is passed through a series of upward deflecting screens placed across the flowpath in a rectangular tank. Microbubbles of air released from the mixture produce a buoyant force which carries contacted particles to the surface. Floated particles released from the microbubbles form a sludge which is supported above the surface of the mixture by a layer of air derived from the microbubbles. A top layer of the sludge is skimmed off according to a predetermined residence time of sludge at the surface. Liquid containing dissolved air is also introduced downstream of each deflecting screen to enhance flotation and clarification.

Abstract: Waste water sludge which contains phosphorous, heavy metals and at least one metal originating from a waste water treatment coagulant, is treated in order to recover the phosphorous and the at least one metal, and to discharge the heavy metals. The at least one metal includes iron.

Abstract: A process for cleaning recycled pulp includes an upright cylindrical vessel having an upright cylindrical screen member open at its top and bottom ends and having a perforated screen wall which is centered on a vertical axis in the vessel. A plurality of upright, elongated blades are mounted for rotation on the vertical axis in close proximity to the screen wall. A pulp slurry entrained with pressurized air is introduced under pressure into an inlet in the bottom of the vessel. The rotating blades clear the screen wall while creating a rising vortex of air bubbles produced by the pressurized air for carrying ink and/or contaminant particles upwardly through the inner volume of the screen member. An "accepts" outlet at the center of the vessel draws off pulp in suspension that has been passed through the screen wall. A "rejects" outlet at the top of the vessel draws off ink and contaminant particles carried by the air bubbles in the upwardly-moving vortex.

Abstract: The method of the present invention comprises introducing a contaminated fluid mixture containing solids, liquid and contaminating fluid into a preliminary separator to separate the contaminating fluid from the principal liquid and solids; tangentially introducing the contaminated fluid mixture into a vertical cylindrical vessel in a circular motion to further separate the contaminating fluid from the principal liquid and solids; introducing air into the contaminated fluid mixture to further separate the contaminating fluid from the liquid and solids; maintaining the circular flow of the contaminated fluid mixture within the vessel to separate the fluid into contaminating fluid, clean liquid and solid contaminants; collecting the contaminating fluid in a reservoir; removing the contaminating fluid from the reservoir; and, discharging the clean liquid from the vessel.

Abstract: A flotation method and apparatus for separating a selected constituent from an effluent of an industrial process is provided. The apparatus includes a conditioning tank and a flotation cell. The conditioning tank allows mixing a flotation reagent with an effluent and includes a mechanism for also dissolving gas in the effluent within the conditioning tank. The flotation cell includes a dissolved gas flotation chamber having an overflow for recovering the selected constituent and a tailings drain. In addition, the flotation cell also includes an added gas flotation chamber having a sparger for injecting gas into the effluent, an overflow for recovering the selected constituent and a tailings drain.

Abstract: A sparger (100) for producing gas bubbles in a liquid comprises a body member (102) having a gas inlet (105) and an outlet portion (106) provided with a gas outlet (108). The outlet portion (106) has an internal bore (110) which is in communication with the gas inlet (105) and the gas outlet (108). The bore (110) has opposite sides which converge in the direction of the outlet (108) to form a tapered region (112) in the bore (110). The bore (110) has a substantially constant diameter along at least a part of its length in an area between the tapered region (112) and the outlet (108). The sparger (100) further comprises a valve member (114) which is moveable into said tapered region (112) towards the outlet (108) for controlling the flow of gas through the outlet (108).

Abstract: A dissolved gas flotation tank system is disclosed which is configured to provide educted gas or air into recirculated effluent fluid from the tank which includes a pump system which increases the dissolution rate of gas into the effluent fluid thereby eliminating the need for retention tanks and related equipment which adds to high equipment costs. The dissolved gas flotation tank system of the present invention also provides a pre-contact chamber for assuring immediate and intimate contact between the suspended solids in an influent feed stream and the recirculated effluent fluid in which gas is dissolved, as well as flocculant when used, to produce a better agglomerate structure for improved flotation and separation. The dissolved gas flotation tank of the present invention also provides an improved means of removing and processing float from the tank, and employs a dewatering system enhanced by the addition of chemicals or flocculants into the float removal system.

Abstract: Process and apparatus for the separation of solid matter via flotation. The flotation process for the separation of solid matter from a suspension takes place via the utilization of centrifugal forces wherein the suspension is brought into rotation in a separating zone so that the floated components are particularly effectively routed to and concentrated at the center of the separating space, whereby, when viewed axially, floated components and the remaining portion of the suspension is guided in the same direction and out of the separating zone, with the avoidance of vortexes in the flow stream achieving particularly favorable separation effects. In addition, several apparatuses, for carrying out the process, are also set forth.

Abstract: In the process for separating off by flotation (pressure release) suspended matter from liquids which are present in a gas-introduction reactor, the suspension to be withdrawn for flotation is conducted at a flow velocity .ltoreq.0.3 m/s against the natural direction of bubble rise, gas being additionally introduced into the suspension. The gas-treated suspension is withdrawn at the bottom of the gas-introduction apparatus and it is fed to flotation.

Abstract: An oil/water separator that employs a rotatable drum for separating oil or other contaminants from a fluid, usually water. This drum is partially immersed within the oil containing fluid such that by its rotation therethrough, an oil film adheres to its outer periphery. A blade assembly scrapes or wipes this film from this outer periphery and gathers such film in an adjacent collection trough.

Abstract: A system to collect by vacuum conveyance, separate, and discharge two mixed immiscible liquids with different specific gravities comprising a grit, sediment, particulate, and floating debris removal/collection chamber 11, vacuum tank 51, optional heavy phase supplemental separation stage 47A, and optional light phase supplemental separation stage 47B. Vacuum tank 51 is under a constant regulated vacuum, which sucks mixed immiscible liquids with different specific gravities from their respective remote source(s) through conduit(s) connected to vacuum tank 51. Collection conduits can have manually, mechanically, or electro-mechanically controlled valves at their source ends. Any grit, sediment, particles, floatable debris, and entrained air in the collection conduits is removed from the mixed liquid stream prior to undergoing any phase separation stages. Initial phase separation occurs automatically in vacuum tank 51, which provides quiescent conditions for gravity separation of mixed immiscible liquids.

Abstract: Disclosed is a clarifier for use in treating a liquid containing non-soluble particles in suspension in order to separate these particles from the liquid. It comprises a tank, a liquid supply duct opening into the bottom portion of the tank and an injector for injecting a gas under pressure into at least part of liquid supplied to the supply duct in order to saturate this liquid with said gas and thus to generate gas bubbles as the saturated liquid is subject to depressurization within the tank. The gas bubbles that are so-generated adhere to the particles in suspension in the liquid and lift them up to form a floating layer of sludge in the top portion of the tank. A scraper is provided in the top portion of the tank for skimming off the layer of sludge while it is formed. A plurality of plates extend at an angle within the tank above the supply duct.

Abstract: A process for recovering protein, fatty and water components from a float material produced by a waste water treatment system, wherein the protein and fatty components can be further processed for inclusion in various products, such as animal feed. The recovered water component can also be further processed before discharge into a sewer system.

Abstract: A method of removing dispersed oil from an oil in water emulsion is accomplished by the steps of dissolving gas in water to form an aerated solution, introducing the emulsion and aerated solution into a treatment vessel in which is positioned a coalescing media formed by an assembly of closely spaced corrugated plates of oleophilic material, the emulsion and aerated solution passing in contact with the plates to cause oil droplets to coalescence on the plates and small gas bubbles carried with the aerated solution to adhere to the oil droplets to increase the buoyancy of the oil droplets so that the oil droplets more readily rise to the surface of the emulsion, accumulated oil being removed from the surface.

Abstract: Flotation apparatus (10) for removing finely divided bodies of an insoluble substance dispersed in an aqueous medium, such as oil and solids dispersed in water, comprises a vertical flotation column (12) having a feed inlet (14) and an outlet (22) for the aqueous medium, a sparging system (16) for generating gas bubbles rising upwardly in the aqueous medium to capture and raise the finely divided bodies of the insoluble substance to the surface of the aqueous medium in the column to form a layer (31) of the insoluble substance on the surface of the aqueous medium, a launder (18) for receiving an overflow of the insoluble substance and an outlet (20) for the insoluble substance in the launder. The apparatus (10) can be used in both countercurrent and co-current fashion. In a particular embodiment, the apparatus includes a mechanism for the intermittent dumping of the layer (31) of insoluble substance from the column (12).

Abstract: A wastewater treatment system and method for substantially reducing or eliminating total suspended solids (TSS), biological organic discharge or biochemical oxygen demand (BOD), and fats, oils and greases (FOG) contaminants. The system includes at least one mixing chamber for mixing wastewater with at least one dewatering agent or chemical and air to form an aerated mixture and at least one tank having a plurality of compartments for facilitating flotation, settling and removal of contaminants from the aerated mixture as it flows through the tank. Preferably, the system includes first and second mixing chambers and first and second tanks arranged in series with each of the tanks including drag lines for removing floating and settled contaminants.

Abstract: A filtration apparatus for an aquarium comprising of mechanical, biological and chemical filter mechanisms for removing impurities from water and an intake tube/pre-filter arrangement for maintaining syphonability of the apparatus during both operating and non-operating states. In an another embodiment, a protein skimmer is combined with the other filter mechanisms.

Abstract: A simplified single cell apparatus and method for removal of suspended impurities in liquids using gas flotation and filtration is provided wherein the method and apparatus are preferably directed to induced gas flotation separation of suspended impurities in combination with a filter media for filtration removal of remaining suspended impurities. A filter media is contained within the single cell apparatus such that liquid exiting the vessel must pass through the filter media after having been subjected to flotation treatment.

Abstract: Components, usually but not exclusively gaseous components, are removed in a liquid medium from gas streams and chemically converted into an insoluble phase or physically removed. Specifically, hydrogen sulfide may be removed from gas streams by oxidation in aqueous chelated transition metal solution in a agitated flotation cell. The same principal may be employed with other procedures in which a gaseous phase is dispersed in a liquid phase to effect an interaction between components present in such phases, for example, to treat or strip or react a component of the liquid phase.

Abstract: A method for removing residual oil from oily water under pressure is provided. The method comprises flowing a liquid stream of an oily water downward through a vertically extended zone to remove the residual oil. A gas is injected into the lower end of the zone and at a rate sufficient to generate bubbles of a predetermined volume in the liquid stream. A sufficient pressure is maintained in the zone to control the rate of expansion of the bubbles to a volume compatible with oil droplets in the liquid stream during upward migration of the bubbles and the oil droplets. The rate of flow of the liquid stream from the lower end of the zone and the rate of flow of the gas from the upper end of the zone are regulated to collect residual oil from a quiescent volume within the upper portion of the zone.