The invention in one form is directed to an airlift pump that is optimized to transfer large volumes of water using very low pumping head. Specifically, the airlift pump is comprised of a pump inlet and outlet which are both located below pond's surface. The pumping force driving the water flow is supplied by the weight of the volume of water displaced by pressurized air into a vertical pipe, and this energy is dissipated by the friction of the rising bubbles pipe entrance head, plus the frictional effects of the inner pipe wall and the energy contained in the water's exit velocity.

The invention in one form is directed to an airlift pump that is optimized to transfer large volumes of water using very low pumping head. Specifically, the airlift pump is comprised of a pump inlet and outlet which are both located below pond's surface. The pumping force driving the water flow is supplied by the weight of the volume of water displaced by pressurized air into a vertical pipe, and this energy is dissipated by the friction of the rising bubbles pipe entrance head, plus the frictional effects of the inner pipe wall and the energy contained in the water's exit velocity.

A bubble generating device for sewage purification includes: an outer cylinder 6 vertically placed in water; an injection port 2A placed at a lower central portion in the outer cylinder 6 for upwardly injecting air as bubble flow supplied from an air supply source; and microbubble generating device 3 placed higher than the injection port 2A for refining bubbles injected from the injection port 2A. A throat portion 30 for narrowing a flow path of bubble flow and water flow which rises in the outer cylinder 6 is placed between the injection port 2A and the microbubble generating device 3.

A dual-action water aerator includes structure that generates fine, fizz-type bubbles and structure that generates larger, more roiling bubbles that cause circulation within a body of water in which the aerator is submerged. The disclosed embodiments include a ring-shaped hub with a central aperture, with a central tube extending axially from the aperture. A number of fine-bubble-producing members extend outwardly from the hub and may be attached to the hub using a twist-lock connection designed to facilitate rapid assembly and deployment of the aerator. An internal air chase extends circumferentially around the aperture. A portion of air supplied to the air chase flows into the fine-bubble-producing members and fizzes out through the members, and another portion of air that is supplied to the air chase flows into the central tube and bubbles up out of the tube in a roiling manner to cause circulation in the body of water.

An aerator assembly for wastewater treatment includes a draft tube and an air supply assembly. The draft tube includes a sidewall and presents open top and bottom tube ends. The air supply assembly includes an air supply conduit and a diffuser body. The diffuser body has an inlet aperture and a bubble generator connected to the inlet. The inlet aperture is connected to the air supply conduit such that the bubble generator receives air from a source of air, to which the air supply conduit is connected. The bubble generator has a plurality of air openings for generating fine air bubbles. The diffuser body is sealingly engaged to the sidewall adjacent the bottom tube end so as restrict upward flow of wastewater through the draft tube past the diffuser body.

A floating aerator that is highly efficient in oxygenating water and wastewater utilizes high-volume, low pressure air that is diffused into a sub-surface oxygen transfer chamber in which water and wastewater is oxygenated. An air lift is created in the oxygen transfer chamber through the discharge of air bubbles in the water column in the aerator. The aerator comprises a floating head having a concave lower surface, a main chamber or barrel that defines the oxygen transfer chamber, and an air diffuser that extends coaxially through the float head and barrel interconnects the float head to the barrel such that there is a discharge slot defined between the lower surface of the float head and the barrel. A ballast ring floats the aerator at the desire level such that a flow of air bubbles and oxygenated water or wastewater are discharged at a subsurface level.

The invention relates to the design of an enclosure for a membrane aeration module, which incorporates a reversible, low-pressure, air-lift pump to encourage a vertical water flow through and between the membranes in the module. These enclosed membrane modules are suitable for use in membrane aerated biofilm reactors, which are used to treat water or wastewater.

A beverage aerator includes a housing, a pump-motor assembly, an uptake tube, and a spray nozzle. The housing is sized to removably seat on a neck of a decanting vessel. The pump-motor assembly is positioned within the housing, and has a pump inlet and a pump outlet. The uptake tube is fluidly coupled to the pump inlet upstream of the pump inlet. The uptake tube has a tube inlet end located below the housing. The spray nozzle is fluidly coupled to the pump outlet downstream of the pump outlet. The spray nozzle is located below the pump-motor assembly and oriented to have a laterally-outward discharge direction.

This document describes a gas streaming device for use between an injection port and a mixing chamber within an airlift pump, and an airlift pump with the gas streaming device. The gas streaming device includes a planar plate with multiple holes extending therethrough, where the holes are dimensioned to direct the gas into multiple micro-streams for streaming air from the injection port into the mixing chamber. An airlift pump in combination with such a gas streaming device is useful for removing anomalously high concentrations of dissolved gas in a liquid. The increased efficiency for this invention may also enable this type of pump to be economic in other applications where it is desirable to lift a liquid or induce flow.

This document describes a gas streaming device for use between an injection port and a mixing chamber within an airlift pump, and an airlift pump with the gas streaming device. The gas streaming device includes a planar plate with multiple holes extending therethrough, where the holes are dimensioned to direct the gas into multiple micro-streams for streaming air from the injection port into the mixing chamber. An airlift pump in combination with such a gas streaming device is useful for removing anomalously high concentrations of dissolved gas in a liquid. The increased efficiency for this invention may also enable this type of pump to be economic in other applications where it is desirable to lift a liquid or induce flow.