A device and method for injection of oxygen-rich gas into a body of liquid with oxygen recycling are disclosed. The device comprises a rotary hollow shaft vertically passing through a float partially immersed in the liquid, an impeller attached to the lower end of the rotary hollow shaft, a columnar structure, surrounding the rotary hollow shaft, mounted on the bottom side of the float and vertically extending into the liquid, a gas diffusion chamber formed by the columnar structure, the float and the liquid surface under the float, and a gas injection conduit passing through the float for delivering the oxygen gas into the gas diffusion chamber, wherein a vacuum is generated in the body of the liquid around the impeller when the impeller is driven to rotate, so that the oxygen-rich gas in the gas diffusion chamber is sucked into the body of the liquid and mixed therein.

A floating equipment, for injection of a gas into liquid effluents or waste water, and more particularly of a gas rich in oxygen into a basin from the surface, including the following elements: a driving device, intended to be disposed over the liquid, provided with a vertical output shaft (8), equipped at its end with a propeller (6) immersed in the liquid a pre-mixing device (5) comprising an injection device (7) positioned above or below a mobile aerator (9) with inclined blades, the propeller being situated at the end of the shaft, under the pre-mixing reactor.

A floating equipment, for injection of a gas into liquid effluents or waste water, and more particularly of a gas rich in oxygen into a basin from the surface, including the following elements: a driving device, intended to be disposed over the liquid, provided with a vertical output shaft (8), equipped at its end with a propeller (6) immersed in the liquid a pre-mixing device (5) comprising an injection device (7) positioned above or below a mobile aerator (9) with inclined blades, the propeller being situated at the end of the shaft, under the pre-mixing reactor.

In one embodiment, a method of reducing at least one of nitrogen, carbon and phosphorous in a lagoon that includes at least three cells.

An air grid for supplying air under pressure. The air grid may be used as an air scour system for a filter for removing at least some impurities (e.g., foreign matter of any nature including a solid, a liquid or a gas) from water or wastewater or as an aerator for aerating wastewater in an aeration tank or basin. The air grid includes an adapter for permitting in field adjustment of one or more components (e.g., drop pipe) of the air grid. Preferably, the adapter houses a portion of an air supply header and a portion of a drop pipe such that the air supply header is disposed above the drop pipe. The adapter may include a detachable sealing assembly. A tool may be provided for inserting and/or removing one or more components of the air grid from the operation environment.

An artificial-whirlpool generator includes a whirlpool generating member including at least one water inlet, a whirlpool generating chamber communicating with the water inlet, and a whirlpool outlet that is formed at a lower end portion of the whirlpool generating member and communicates with the whirlpool generating chamber; a position-fixing means that fixes the whirlpool forming member such that the entirety of the whirlpool generating member or only a portion of the whirlpool generating member, including the whirlpool outlet is submerged; and a swirling flow forming unit that forces water in a waterbody to be introduced into the whirlpool generating chamber through the water inlet and rotates the introduced water in one direction around an axle provided at a center portion of the whirlpool generating chamber to form a whirlpool that descends toward the whirlpool outlet.

An artificial-whirlpool generator includes a whirlpool generating member including at least one water inlet, a whirlpool generating chamber communicating with the water inlet, and a whirlpool outlet that is formed at a lower end portion of the whirlpool generating member and communicates with the whirlpool generating chamber; a position-fixing means that fixes the whirlpool forming member such that the entirety of the whirlpool generating member or only a portion of the whirlpool generating member, including the whirlpool outlet is submerged; and a swirling flow forming unit that forces water in a waterbody to be introduced into the whirlpool generating chamber through the water inlet and rotates the introduced water in one direction around an axle provided at a center portion of the whirlpool generating chamber to form a whirlpool that descends toward the whirlpool outlet.

In one embodiment, hydrodynamic cavitation lyses influent bacteria, releasing intracellular enzymes, and creates CaCO.sub.3 seed crystals that are discharged at the base of the water column. Bottom-dwelling upflow anaerobic sludge blanket (UASB)-like granules grow in a dense, viscous N, P & Ca++ rich fluid (hydrolytic brine). The brine hydrolyzes ancient sludge and fresh solids into simple liquids. The granules convert hydrolyzed liquids into gas. New CaCO.sub.3 seeds grow at the produced gas/supernatant interface and propagate across the entire lagoon. Once the sludge inventory is digested, there is an excess of granules that modulate their gross productivity in response to substrate load, pH, and temperature. In one specific example, the treated lagoon has no odor, is free of gelled sludge and effluent

A self-deploying float assembly to support mechanical equipment such as aerators and mixers for use in water, wastewater and process water stream treatment basins and a method of installing same.

A self-deploying float assembly to support mechanical equipment such as aerators and mixers for use in water, wastewater and process water stream treatment basins and a method of installing same.