A device for generating bubbles, comprising a porous material having at least one hydrophilic surface (1), arranged such that a liquid (7) in which the bubbles (6) are intended to be formed may contact the hydrophilic surface (1) and at least one hydrophobic surface (2), arranged such that a gas (5) used to generate the bubbles (6) may flow past the hydrophobic surface (2) before it flows past the hydrophilic surface (1). The device may be used for creating fine bubbles in numerous applications, such as wastewater treatment, plant cultivation, aquafarming, aeration systems, bioreactors, fermeters, oil extraction or fuel cells.

Disclosed herein are techniques and methods for dispersing a volume of gas in a beverage contained in an unpressurized container.

There is disclosed a stand-alone, independent and re-usable valve that can be mounted to a conventional food container, such as a food bag, and can be coupled to a suction pump. The valve has a first part for insertion into the food container and a second part for mounting onto the first part with a wall of the food container in between, to obtain an air-tight closure of the valve. Further, an adapter is provided that can cooperate with a single type of coupling element for a suction pump at one end and can cooperate with various types of valves at another end. Additionally, an aerator is provided that can be coupled to a suction pump operating in a blowing mode for aerating liquid.

A fine bubble generating apparatus has a storage tank, a liquid feeding unit suctioning and feeding liquid stored in the storage tank, a gas discharge unit discharging gas into the liquid which is being fed by the liquid feeding unit, and a storage tank. The gas discharge unit includes a gas discharge member with pores having pore diameters of 1.5 μm or less, and a base member having a groove formed in a surface contacting the gas discharge surface of the gas discharge member. The liquid feeding unit moves the liquid along the gas discharge surface of the gas discharge member by causing the liquid to flow in a flow channel enclosed by the gas discharge surface of the gas discharge member and the groove of the base member such that a velocity relative to the gas discharge member is not less than 1 msec.

A mixing aerator is disclosed that includes a housing defining a chamber having a bottom end and a top end, the housing having at least one inlet and at least one outlet; and a longitudinally extending diffuser disposed within the chamber and configured to deliver air bubbles into the chamber when the chamber is filled with liquid. The diffuser includes (a) a tubular elastomeric membrane having a plurality of perforations and, within the tubular elastomeric membrane, (b) an air pipe having a plurality of openings, the openings being larger and fewer than the perforations, and the tubular membrane having upper and lower ends that are sealed against an outer surface of the air pipe.

A system may include a nanobubble generator that uses a shearing force applied by a fluid received through a fluid inlet and a negative pressure applied to an outlet by a pump to provide a vacuum-assisted shear flow nanobubble generator system. In some implementations, the system may include a nanobubble generator including a porous component including a chamber coupled to receive a gas and including a surface having a plurality of gas-permeable openings. The nanobubble generator may include an inlet and an outlet on opposing sides of the porous component to direct the fluid across the openings. The system may include a pump to apply a negative pressure to the outlet of the nanobubble generator. The negative fluid pressure and the fluid flow across the openings cooperate to form nanobubbles at low injected gas pressures, increasing the efficiency of production of nanobubble solutions with pressure sensitive gasses, such as ozone.

An aeration device has an entrainment chamber for mixing air and water in a body of water, wherein the air becomes partially dissolved into the water, thus creating water enriched with dissolved air, and excess air that did not dissolve into the water. An air input introduces air into the aeration device and a water input introduces water into the aeration device. Water enriched with dissolved air exits a water discharge of the aeration device at a first level within the body of water. An air exhaust manifold wherein the excess air can exit the water discharge while remaining inside the aeration device, an exhaust stack that permits the excess air to travel up from the air exhaust manifold, and an exhaust that permits the excess air to exit the aeration device at a second level within or above the body of water.

A hollow expansion chamber of the present invention is configured to temporarily contain an expansion of bubbles during an aeration process for aerating a liquid, where a chamber body of the expansion chamber has an oblate spheroid shape. When moving circumferentially downward along the chamber body starting from a maximum inside diameter, the oblate spheroidal shape of a bottom portion has a first integral transition that is a tangential transition to a first frustoconical shape. Continuing moving circumferentially downward, the first frustoconical shape has a second integral transition to a cylindrical extension. The cylindrical extension at a distal end has a bottom opening configured to fit within an opened bottleneck. The first frustoconical shape has a minimum angle of 15 degrees relative to a horizontal plane. The second integral transition is a radial second integral transition having an inside surface radius of at least 0.25 inches.

An all-ceramic diffuser supplies microbubbles of a narrow range of size to create a steady flow of bubbles of generally uniform size in an aqueous medium, such as process water in a wastewater treatment plant. The diffuser is formed of a porous body core, with pore sizes of e.g. 30 .Math.m or larger, an upper ceramic membrane that covers the upper surface of the body core, and has mean pore size of e.g., 3 to 15 .Math.m. A lower ceramic membrane covers the bottom surface of the body core, and has a finer pore size than the upper ceramic membrane, so that the capillary pore size of the smaller pores will act as a seal; consequently all of the air flow is through the upper ceramic membrane. A ceramic fitting connects the associated air supply with the porous body core which serves as plenum.

A diffuser is disclosed and includes a channel with an inner portion having an inlet and an outlet through which a gaseous substance enters and exits the diffuser, respectively. The inner portion includes a first conical section that has an increasing cross-sectional area, taken along a plane perpendicular to a central axis, in a first direction. The inner portion also includes a second conical section that has a decreasing cross-sectional area, taken along a plane perpendicular to the central axis, in the first direction. The second conical section is communicatively coupled with the first conical section. The outer portion includes a first annular section that has an increasing cross-sectional area, taken along a plane perpendicular to the central axis, in a second direction opposite the first direction. The diffuser further includes a plurality of orifices that communicatively couple the second conical section with the first annular section.