Device and method for generating nano-bubble capable of being immersed

Abstract

To provide a permeation device and a method for generating nano-bubble in a certain liquid volume, the device capable of being immersed .SOLUTION: A device includes a motor having a rotatable shaft, a permeable member which can be combined with an intake port and is axially rotatable and a rotatable cylindrical support body which is combined with the rotatable shaft of the motor and has an internal cavity for storing the permeable member which is axially rotatable. When rotated, the axially rotatable permeable member is rotated so that a surface velocity of the rotatable permeable member imitates an axial turbulent flow above the turbulent threshold in liquid that allows the liquid to shear gas from an outer surface of the axially rotatable permeable member, thereby, forming nano-bubbles in the liquid.SELECTED DRAWING: Figure 1D

Description

[Technical field]

[0001] Claiming priority This application claims priority under 35 USC §119(e) to U.S. patent application Ser. No. 62 / 818,573, filed Mar. 14, 2019, the entire contents of which are incorporated herein by reference.

[0002] Technical Field The present disclosure relates to a submersible venting device and method for generating nanobubbles in a liquid volume. [Background technology]

[0003] background Various systems, such as pump or blower systems, have been used to supply gas to a volume of liquid medium to obtain a desired gas saturation level in the liquid medium. Gas saturation is the ratio of the concentration of gas dissolved in the liquid medium to the maximum concentration of gas that can be dissolved in the liquid medium at stable equilibrium. Aeration systems may use one or more pumps to recirculate the liquid (e.g., water) to dissolve the gas in the liquid.

[0004] As an example, the amount of dissolved oxygen in a water source can be indicative of its water quality. Various organisms utilize the oxygen present in the water source. In some cases, it is desirable to maintain a certain level of oxygen saturation in the liquid. In some cases, it is desirable to increase the amount of dissolved oxygen in the water.

[0005] One drawback of current systems is that many are not viable or applicable under certain circumstances. For example, aeration systems may not be efficient for large volumes of water (or other liquid media). Also, pumping and recirculating large volumes of water may not be feasible due to inefficiencies or insufficient access to equipment. Consequently, alternative means of obtaining increased oxygen saturation levels are needed in such conditions. Summary of the Invention

[0006] overview As used herein, the term "nanobubbles" refers to bubbles having a diameter of less than 1 micrometer (μm). Larger than nanobubbles are microbubbles, which are bubbles having a diameter of 1 μm or more and less than 50 μm. Macrobubbles are bubbles having a diameter of 50 μm or more.

[0007] Described herein is an apparatus for generating nanobubbles in a volume of unaerated liquid (e.g., water). The apparatus includes a motor, a rotatable permeable member, and a rotatable tubular support. The motor includes a rotatable shaft. The rotatable permeable member includes a hollow body having a wall extending along a longitudinal axis. The wall includes a plurality of pores such that gas introduced into the rotatable permeable member can flow through the plurality of pores within the hollow body. The distance of each pore location relative to the longitudinal axis is approximately the same. The rotatable permeable member is coupleable to an inlet configured to introduce gas from a gas source into the interior of the rotatable permeable member. The rotatable permeable member is coupled to the rotatable shaft of the motor and adapted to rotate axially about the longitudinal axis with the rotatable shaft, resulting in an axially rotatable permeable member.

[0008] The apparatus further includes a tubular support having an elongated body having a wall and defining an internal cavity, the wall defining a plurality of perforations. The internal cavity of the tubular support is configured to accommodate a rotatable permeable member. The tubular support is coupled to a rotatable shaft of the motor and rotatable therewith. Upon rotation, the tubular support is adapted to introduce liquid into the internal cavity of the tubular support and to move liquid away from an exterior surface of the body of the rotatable permeable member.

[0009] When rotated, the rotatable permeable member and the tubular support mimic turbulence above a turbulence velocity threshold in the liquid (e.g., 2 m / s or greater) such that the liquid shears gas from the outer surface of the rotatable permeable member to form nanobubbles. This "simulated" turbulence in the surrounding liquid at levels above the turbulence threshold can promote nanobubble formation by shearing gas from the surface of the rotatable permeable member to form nanobubbles and preventing them from coalescing.

[0010] This and other aspects can include one or more of the following features.

[0011] The rotatable permeable member can have a circumference defined by an outer diameter sized to mimic turbulent flow above a turbulence threshold of the liquid.

[0012] The pores of the rotatable permeable member may have diameters in the range of 200 nanometers (nm) to 50 μm, or diameters less than or equal to 50 μm.

[0013] The rotatable permeable member may be coupled to a rotatable tubular support.

[0014] The perforations in the rotatable tubular support may be circular, semicircular, rectangular, cubic, elliptical, triangular, or slot-shaped.

[0015] The device may optionally include a base and a protective housing (e.g., a casing or frame). The housing is defined by an exterior wall extending between a first end and a second end coupled to the base. The exterior wall is permeable to liquids (such as water). The exterior wall defines a plurality of perforations. In some embodiments, the exterior wall may include a screen or mesh-like component. The rotatable permeable member and the tubular support are disposed within the protective housing.

[0016] The protective housing is fixed to the base so that it cannot rotate.

[0017] The apparatus may include an impeller disposed within the protective housing, the impeller adapted to induce a flow of liquid into and out of the rotatable tubular support and away from a surface of the rotatable permeable member.

[0018] The nanobubbles can have an average diameter of less than 500 nm, less than 200 nm, in the range of about 10 nm to about 500 nm, or in the range of about 75 nm to about 200 nm.

[0019] In some embodiments, an apparatus for generating nanobubbles in a volume of liquid includes a motor with a rotatable shaft and a rotatable permeable member, the rotatable permeable member including a body having a wall and a plurality of perforations through which gas introduced into the rotatable permeable member can flow, the rotatable permeable member is coupleable to an inlet configured to introduce gas from a gas source into the rotatable permeable member, the rotatable permeable member being coupled to the rotatable shaft of the motor and adapted to rotate with the rotatable shaft.

[0020] The rotatable permeable member further includes at least one radially extending member. The radially extending member may include at least one blade, vane, propeller, or combination thereof. When rotating with the at least one radially extending member, the rotatable permeable member is adapted to move liquid away from an outer surface of the body of the rotatable permeable member and to mimic turbulence above a turbulence threshold in the liquid that causes gas from the outer surface of the rotatable permeable member to shear into the liquid, thereby forming nanobubbles in the liquid.

[0021] A method is also described for generating nanobubbles in a volume of liquid using the above device. At least a portion of the device is immersed in the liquid. Gas is introduced from a gas source through an inlet into the rotatable permeable member at a gas pressure that forces the gas through the pores of the rotatable permeable member. Rotating the rotatable permeable member and the tubular support mimics turbulence in the liquid above a turbulence velocity threshold such that the liquid shears the gas from the exterior surface of the rotatable permeable member to form nanobubbles.

[0022] The pressure of the gas entering the permeable member can range from about 1 atmosphere (atm) to about 10 atm.

[0023] The above-described apparatus and methods may be used in a number of applications, including the treatment of water.

[0024] The above described apparatus and methods provide numerous advantages. For example, the generation of nanobubbles may allow for more efficient diffusion and / or dissolution of gas in the surrounding liquid compared to the generation of larger gas bubbles. This higher transfer efficiency of nanobubbles may be particularly useful in applications where it is desired to aerate a large volume of liquid, but it may not be feasible or practical to use traditional or modern aeration techniques, such as pumping, to effect recirculation of the large volume of liquid. Some non-limiting examples of such large volumes of liquid include lakes, ponds, canals, and oceans.

[0025] Rotation of the rotatable permeable member may be performed by a drive mechanism that is immersed, partially immersed, or above the surface of the liquid in which aeration is desired. The rotatable permeable member and the tubular support may be rotated together simultaneously. The gas flowing into the rotatable permeable member may be low pressure gas (e.g., gas with a pressure of 10 atmospheres or less), for example, from a blower or air pump. In some embodiments, the device (including the rotatable permeable member and drive mechanism) may be fully immersed in the liquid in which aeration is desired. In some embodiments, the device may be used to generate nanobubbles in the liquid in which aeration is desired without the need to further pump (i.e., induce flow) the liquid in which aeration is desired. The device may be compact in size (e.g., on the order of 8 inches in diameter) to allow placement in tight spaces such as manholes. The device may be integrated with any rotating instrument that can provide sufficient rotational speed to the rotatable permeable member to generate nanobubbles.

[0026] The devices provided herein advantageously mimic the flow conditions necessary to generate nanobubbles in a liquid under any flow conditions (e.g., no flow, laminar or turbulent flow conditions). Exposure to or generation of actual turbulence is therefore not necessary for nanobubble generation. Rotation of the rotatable permeable member mimics turbulence above a turbulent velocity threshold in the liquid such that the liquid shears gas from the outer surface of the rotatable permeable member to form nanobubbles. Thus, the device provides the benefit of generating nanobubbles independent of the flow conditions of the liquid.

[0027] [The present invention 1001] a motor including a rotatable shaft; An axially rotatable permeable member including a body having a wall and a plurality of pores, a gas introduced into the axially rotatable permeable member is capable of flowing through the plurality of pores; the axially rotatable permeable member is coupleable to an inlet configured to introduce gas from a gas source into the axially rotatable permeable member; the axially rotatable permeable member is coupled to a rotatable shaft of the motor and adapted to rotate with the rotatable shaft; the axially rotatable permeable member; and A rotatable tubular support including an elongated body, the elongated body having a wall and defining an interior cavity; the wall defines a plurality of perforations; the interior cavity of the rotatable tubular support is configured to accommodate the axially rotatable permeable member; the rotatable tubular support is coupled to a rotatable shaft of the motor for rotation therewith; When rotated, the rotatable tubular support is adapted to introduce liquid into the interior cavity of the rotatable tubular support and to move liquid away from an exterior surface of a body of the rotatable permeable member; When rotated, the axially rotatable permeable member is adapted to mimic turbulence above a turbulence threshold in the liquid, causing gas from an outer surface of the axially rotatable permeable member to shear into the liquid, thereby forming nanobubbles in the liquid. The rotatable cylindrical support 1. An apparatus for generating nanobubbles in a volume of liquid, comprising: [The present invention 1002] The apparatus of the present invention 1001, wherein the axially rotatable transmissible member is coupled to a rotatable tubular support such that the axially rotatable transmissible member is concentrically positioned within the rotatable tubular support. [The present invention 1003] The apparatus of invention 1001 or invention 1002, wherein the perforations in the rotatable cylindrical support are circular, semicircular, rectangular, cubic, elliptical, triangular, or slot-shaped. [The present invention 1004] Further comprising a base and a housing; the housing is defined by an exterior wall extending between a first end and a second end coupled to the base, the exterior wall defining a plurality of perforations, and an axially rotatable permeable member and a rotatable tubular support are disposed within the housing. Any one of the devices 1001 to 1003 of the present invention. [The present invention 1005] The device of the present invention 1004, wherein the housing is fixed to a base so that it cannot rotate. [The present invention 1006] further comprising an impeller disposed within the housing; the impeller adapted to induce a flow of liquid into and out of the housing and away from a surface of an axially rotatable permeable member; The apparatus of the present invention 1004 or 1005. [The present invention 1007] The apparatus of any of claims 1001-1006, wherein the axially rotatable permeable member has an outer periphery defined by an outer diameter sized to mimic turbulent flow above the turbulence threshold of the liquid. [The present invention 1008] The apparatus of any one of claims 1001 to 1007, wherein the pores of the rotatable permeable member have a diameter in the range of 200 nm to 50 µm. [The present invention 1009] The apparatus of any one of claims 1001 to 1007, wherein the pores of the rotatable permeable member have a diameter of 50 µm or less. [The present invention 1010] The apparatus of any one of claims 1001 to 1009, wherein the nanobubbles have an average diameter of less than 500 nm. [The present invention 1011] The device of any one of claims 1001 to 1010, wherein the nanobubbles have an average diameter of less than 200 nm. [The present invention 1012] The device of any one of claims 1001 to 1011, wherein the nanobubbles have an average diameter in the range of about 10 nm to about 500 nm. [The present invention 1013] The device of any of claims 1001 to 1012, wherein the nanobubbles have an average diameter in the range of about 75 nm to about 200 nm. [The present invention 1014] A method for generating nanobubbles in a volume of liquid using any of the devices of the present inventions 1001 to 1013, comprising the steps of: immersing at least a portion of the device in a liquid; introducing gas from a gas source through an inlet into the axially rotatable permeable member at a gas pressure that forces the gas through the plurality of pores of the axially rotatable permeable member; and Rotating the rotatable tubular support and the axially rotatable permeable member such that the liquid shears gas from an outer surface of the axially rotatable permeable member to mimic turbulence above a turbulence threshold in the liquid, thereby forming nanobubbles. [The present invention 1015] The method of claim 1014, wherein the pressure of the gas flowing into the axially rotatable permeable member is from about 1 atmosphere to about 10 atmospheres. [The present invention 1016] A method for treating water, comprising the steps of: A process of generating nanobubbles dispersed in a volume of liquid comprising a source of water requiring treatment, using any of the apparatuses of the present invention 1001-1013. [The present invention 1017] a motor including a rotatable shaft; An axially rotatable permeable member including a body having a wall and a plurality of pores, a gas introduced into the axially rotatable permeable member is capable of flowing through the plurality of pores; the axially rotatable permeable member further includes at least one radially extending member; the axially rotatable permeable member is coupleable to an inlet configured to introduce gas from a gas source into the axially rotatable permeable member; the axially rotatable permeable member is coupled to a rotatable shaft of the motor and adapted to rotate with the rotatable shaft; the axially rotatable permeable member Including, When rotated, the axially rotatable permeable member to direct liquid away from an exterior surface of the body of the axially rotatable permeable member; and shearing gas from an outer surface of the axially rotatable permeable member into a liquid to mimic turbulence above a turbulence threshold in the liquid; adapted to form nanobubbles in the liquid. A device for generating nanobubbles in a volume of liquid. [The present invention 1018] The method of claim 1017, wherein the radially extending members include one or more blades, vanes, propellers, or combinations thereof. The details of one or more embodiments of the presently disclosed subject matter are set forth in the accompanying drawings and description. Other features, aspects, and advantages of the subject matter will become apparent from the description, drawings, and claims. [Brief description of the drawings]

[0028] [Figure 1A] FIG. 1A is an exploded perspective view of an exemplary venting device. [Figure 1B] FIG. 1B is a perspective view of the venting device of FIG. 1A in an assembled configuration. [Figure 1C] FIG. 1C is a top view of the venting device of FIG. 1A in an assembled configuration. [Figure 1D] FIG. 1D is a side view of the venting device of FIG. 1A in an assembled configuration. [Figure 1E] FIG. 1E is a cross-section of the side view shown in FIG. 1D. [Figure 1F] FIG. 1F is a side view of the ventilation device of FIG. 1A with the housing removed. [Figure 1G] FIG. 1G is a cross-section of the side view shown in FIG. 1F. [Figure 1H] FIG. 1H is an exploded side view of the venting device of FIG. 1A. [Figure 1J] FIG. 1J is a cross-section of the exploded side view shown in FIG. 1H. [Figure 1K] FIG. 1K is a top cross-sectional view of the venting device of FIG. 1A. [Figure 2A] FIG. 2A is a top perspective view of a non-rotating portion of the venting device of FIG. 1A. [Figure 2B] FIG. 2B is a bottom perspective view of the non-rotating portion shown in FIG. 2A. [Figure 2C] FIG. 2C is a side view of the non-rotating portion shown in FIG. 2A. [Figure 2D] FIG. 2D is a cross-section of a side view of the non-rotating portion shown in FIG. 2C. [Figure 3A] FIG. 3A is a top perspective view of a rotating portion of the venting device of FIG. 1A. [Figure 3B] FIG. 3B is a bottom perspective view of the rotating portion shown in FIG. 3A. [Figure 3C] FIG. 3C is a side view of the rotating portion shown in FIG. 3A. [Figure 3D] FIG. 3D is a cross-section of a side view of the rotating portion shown in FIG. 4C. [Figure 3E] FIG. 3E is a perspective view of one example of a tubular support that may be included in the venting device of FIG. 1A. [Figure 3F] FIG. 3F is a perspective view of one example of a tubular support that may be included in the venting device of FIG. 1A. [Figure 4] FIG. 4 is a schematic diagram of one example of a rotatable permeable member that may be included in the venting device of FIG. 1A. [Diagram 5] Figures 5A, 5B, and 5C are perspective views of an example of a rotatable penetrable member. [Figure 6] FIG. 6 is a flow chart of an exemplary method for liquid venting. [Figure 7] FIG. 7 is a flow chart of an exemplary method for liquid venting. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Detailed Description The present disclosure describes a submersible aeration device for generating nanobubbles in a given volume of liquid carrier (e.g., a volume of water). A gas, such as oxygen, nitrogen, or air, can be flowed through the pores of the rotatable permeable member, and under turbulent conditions above the turbulence threshold of the liquid created by the rotation of the rotatable permeable member, the liquid can shear the gas to generate nanobubbles and aerate the liquid. The nanobubbles have a diameter of less than 1 micrometer (μm). In some embodiments, the nanobubbles have a diameter of 200 nanometers (nm) or less.

[0030] The venting devices and methods may be implemented in a variety of situations. An example includes a tank that does not have fittings for connecting to an add-on venting system. The described venting devices and methods may be implemented in reactors and / or tanks installed in wastewater treatment plants or other industrial facilities, such as manhole lift stations or other pumping stations where the device may be lowered into a wetwell to transfer gas to liquid, or the described venting devices and methods may be implemented in storm drains, drainage ditches, or irrigation ditches where the liquid depth is shallow (e.g., only 6 inches deep).

[0031] The described aeration devices and methods may also be implemented in a body of water, e.g., at the bottom of a body of water, e.g., at depths of several hundred feet, in a lake or other aquatic environment, for purposes of algae control and / or to increase oxygen levels.

[0032] Other applications of the aeration devices and methods include concrete manufacturing, e.g., to modify one or more properties of concrete. The described aeration devices and methods may also be implemented in swimming pools to reduce the use of chlorine or other oxidizing agents, or in the treatment of irrigation waterways, e.g., by homeowners in private docks to restore natural oxygen levels to stagnant water.

[0033] The described aeration devices and methods may also be implemented in aquaponics and / or ornamental fish tanks, or in ponds, such as decorative ponds, where it may not be desirable to install accessories (such as aeration devices) outside the pond. The described aeration devices and methods may be implemented in feed tanks to keep fish with sufficient oxygen concentrations to live longer, or in marine aquaculture, for example, for fish and / or crustaceans. Other applications include artificial ponds, reservoirs, and / or distribution systems for holding water, such as those used to store or convey oil field produced water, reclaimed water, treated wastewater, and / or drinking water, for example, for aeration, oxidation, and oil separation.

[0034] 1A-1K show an exemplary venting device 100. The device 100 includes a base 101, a drive mechanism 150 coupled to the base 101, a protective housing 102 coupled to the base 101, a rotatable permeable member 103 disposed within the protective housing 102, and an inlet 104 indirectly coupled to the rotatable permeable member 103 (e.g., the inlet 104 may be indirectly coupled to the rotatable permeable member via a bracket 107 and / or a rotary joint 105). The drive mechanism 150 may provide rotation. The drive mechanism 150 includes a rotatable component 150a. In some embodiments, the drive mechanism 150 is a motor and the rotatable component 150a is a rotatable shaft. In some embodiments, the drive mechanism 150 is a gear box and the rotatable component 150a is a gear shaft.

[0035] The protective housing 102 is defined by an outer wall 102a extending between a first end 102b and a second end 102c. The first end 102b is coupled to the base 101. The protective housing 102 defines a plurality of perforations 102d configured to allow liquid to pass through the outer wall 102a of the protective housing 102.

[0036] The rotatable permeable member 103 has a body defining a longitudinal axis "X1" (see FIG. 1A) and is axially rotatable about the longitudinal axis X1. The rotatable permeable member 103 is coupled to a rotatable component 150a of the drive mechanism 150 (e.g., a rotating shaft of a motor or a gear shaft of a gearbox) such that the rotatable permeable member 103 rotates together with the rotatable component 150a of the drive mechanism 150.

[0037] In some embodiments, such as a gearbox drive system, the rotatable component 150a may be attached to the top of the shaft, and the entire drive shaft may be hollow. In such an example, the gas is introduced above the surface of the liquid through the rotatable component 150a, passes through the drive shaft, and enters the rotatable permeable member. The air inlet 104 is configured to provide the gas to the rotatable permeable member 103 through indirect or direct coupling. The rotatable permeable member 103 is configured to exhaust the gas through its pores. The liquid passing through the protective housing 102 may shear the gas from the surface of the rotating permeable member 103, generating nanobubbles from the gas.

[0038] Pedestal 101 is coupled to drive mechanism 150 (e.g., a motor), for example, by attaching base 101 to drive mechanism 150 (e.g., a motor) with one or more screws and / or a latch. Base 101 may secure one or more non-rotating portions of device 100 (such as protective housing 102) to a non-rotating portion of the drive mechanism (e.g., a stator of motor 150). Although shown to be generally circular in FIG. 1A, base 101 may have any shape.

[0039] In various aspects, the protective housing 102 is an optional component. The protective housing 102 may protect the components of the device 100 within the protective housing 102 (such as the rotatable permeable member 103) from contact with foreign objects such as stones, rags, or any other large solid objects that may be suspended in the surrounding liquid or any other material that may damage the internal components of the device 100. In some embodiments, the protective housing 102 is joined to the base 101 by welding, such that the base 101 and the protective housing 102 form a unitary structure. The perforations 102d allow liquid to pass through the protective housing 102 so that liquid can flow between the internal components of the device 100 (such as the rotatable permeable member 103), as shown in FIG. 1K. Although shown to be generally circular in FIG. 1A, the perforations 102d may have any shape. The perforations 102d may be uniform in size or may vary in size. The perforations 102d may be uniformly or randomly distributed throughout the protective housing 102. The protective housing provides the benefit of allowing liquid to flow freely to the internal components of the device (e.g., the rotatable permeable member 103) while preventing debris (e.g., fibrous plant matter) from becoming entangled in the internal components.

[0040] The rotatable permeable member 103 may define a plurality of pores along its wall. In various embodiments, the pores are located along the wall such that the center of each pore (along at least one cross-section) is approximately equidistant from the longitudinal axis. A gas (such as air, oxygen, nitrogen, or ozone) may be supplied to the rotatable permeable member 103. As the permeable member 103 rotates, it mimics a turbulent flow in the surrounding liquid (e.g., water) that exceeds a turbulent velocity threshold (e.g., 2 m / s or greater). The liquid then shears the gas exiting the pores to form nanobubbles dispersed in the surrounding liquid. Some non-limiting examples of materials that may be used to construct the rotatable permeable member 103 include metals, ceramics, and plastics. Although shown generally cylindrical in FIG. 1A, the rotatable permeable member 103 may have other shapes, such as an elongated member having an elliptical cross-section. The rotatable permeable member 103 is described in more detail below.

[0041] The air inlet 104 is configured to couple to a gas source, such as a blower or air pump, or any other source of compressed gas, so that gas may be introduced into the rotatable permeable member 103. In some embodiments, the air inlet 104 includes a tube fitting 104a. In some embodiments, the air inlet 104 includes a gas tube fitting 104b that may be coupled to a gas source.

[0042] The device 100 includes a rotary joint 105 coupled to the rotatable permeable member 103 and / or to some or all of the other components of the device. A portion of the rotary joint 105 coupled to the rotating permeable member 103 can rotate with the rotating permeable member 103, while the remaining portion of the rotary joint 105 does not rotate with the rotating permeable member 103. For example, the rotating portion of the rotary joint 105 can be within a non-rotating housing of the rotary joint 105. The air inlet 104 can be coupled to the non-rotating portion of the rotary joint 105. The rotary joint 105 and the gas source can be coupled to opposite ends of the air inlet 104. For example, the rotary joint 105 can be coupled to a first end of the tube fitting 104a, and the gas tube fitting 104b can be coupled to a second end of the tube fitting 104a opposite the first end. Gas may flow either directly or indirectly (e.g., via a shaft and / or rotary joint 104) from a gas source, through an inlet 104, to the rotatable permeable member 103. The rotary joint 105 may include radial bearings that prevent radial slippage of a rotating portion of the rotary joint 105 relative to a non-rotating portion of the rotary joint 105.

[0043] The device 100 also includes a tubular support 106 coupled to the rotatable penetrable member 103. The tubular support 106 may be coupled to both ends of the rotatable penetrable member 103 along the axis of rotation of the rotatable penetrable member 103. The rotatable penetrable member 103 is disposed within the tubular support 106 in certain embodiments. The rotatable penetrable member 103 and the tubular support 106 may be concentrically aligned tubular members. The tubular support 106 may rotate with the rotatable penetrable member 103. In some embodiments, the tubular support 106 is attached to the penetrable member 103 (e.g., by welding). In some embodiments, the tubular support 106 and the rotatable penetrable member 103 are formed as a unitary structure. The tubular support 106 reduces or eliminates torsional moments on the rotatable penetrable member 103 in various embodiments.

[0044] In FIGS. 3A-3D, the tubular support 106 has a cylindrical body defined by a first wall (e.g., an upper wall), a second wall (e.g., a lower wall), and a cylindrical side wall extending between the first and second walls. The tubular support 106 has an outer diameter larger than the outer diameter of the rotatable permeable member 103. In some embodiments, the tubular support 106 may define a plurality of perforations. The perforations may allow liquid to flow to and from the rotatable permeable member 103. The perforations may be disposed on the surface of the first wall, the second wall, the side wall, or combinations thereof of the tubular support 106. The perforations may be circular, semicircular, rectangular, cubic, elliptical, triangular, slotted, finned, etc. The perforations may be of uniform size or of different sizes (e.g., the size of the perforations may gradually increase along the axial length of the tubular support). The perforations of the tubular support 106 are substantially larger than the pores of the permeable member 103 in various embodiments. The perforations in the tubular support may be the same or different in shape as the pores in the permeable member 103. The perforations may be uniformly or randomly distributed throughout the tubular support 106. Other examples of tubular supports 106 are shown in Figures 3E and 3F.

[0045] Once the liquid has been aerated by the nanobubbles generated by the rotatable permeable member 103, it may be desirable to transport the liquid containing the nanobubbles away from the rotatable permeable member 103 so that new liquid (not including nanobubbles released from the rotatable permeable member) can flow to the surface (e.g., the exterior surface) of the rotatable permeable member 103 and be aerated. Inducing a flow of the surrounding liquid to and from the rotatable permeable member 103 may allow for the continuous generation of nanobubbles. During the rotational movement of the cylindrical support 106 and the rotatable permeable member 103 together, the surrounding liquid may flow into the inner volume of the cylindrical support 106 through the perforations in the end face of the cylindrical support 106. The rotatable permeable member 103 may be rotated (e.g., by the motor 150) at a rotational surface velocity corresponding to a transaxial flow velocity equal to or greater than the turbulent flow velocity of the liquid at the surface of the rotatable permeable member 103. The simulated turbulence of the surrounding liquid at a level above the turbulence threshold may promote the formation of nanobubbles by shearing gas from the surface of the rotatable permeable member 103 to form nanobubbles and preventing them from coalescing. A rotational facial velocity may be considered to mimic turbulence if it has an equivalent transaxial flow velocity with a Reynolds number above 3,500. The simulated turbulence serves to shear gas bubbles from the surface of the rotatable permeable member 103.

[0046] In operation, the rotation of the cylindrical support 106 allows the liquid (having nanobubbles generated by the rotatable permeable member 103) to flow radially outward through the perforations on the outer surface of the cylindrical support 106. The rotation of the cylindrical support 106 serves the function of removing newly formed nanobubbles from near the surface of the rotatable permeable member 103 to prevent nanobubbles from coalescing. The actual flow is generated by the action of the cylindrical support 106 and the arrangement of perforations defined by its various surfaces. As the cylindrical support 106 rotates, the liquid containing nanobubbles contained within the cavity between the rotatable permeable member and the cylindrical support flows radially away from the rotatable permeable member and is replaced by new liquid flowing in through the perforations on the end surface of the cylindrical support 106. Thus, the rotation of the cylindrical support 106 promotes the circulation of the surrounding liquid to and from the surface of the rotatable permeable member 103, thus promoting the continued generation of nanobubbles.

[0047] The device 100 may include a bracket 107. The bracket 107 may be coupled to the housing 102 (e.g., the second end 102c of the housing 102). In some embodiments, the bracket 107 is welded to the housing 102. The bracket 107 may define an internal bore within which the rotary joint 105 may reside. The bracket 107 may prevent a non-rotating portion of the rotary joint 105 (e.g., the housing of the rotary joint 105) from rotating, while a rotating portion of the rotary joint 105 rotates with the rotatable permeable member 103. The bracket 107 may include a slot within which the inlet 104 may reside. In some embodiments, the slot in the bracket 107 may prevent the inlet 104 from rotating. For example, the slot in the bracket 107 may prevent the inlet 104 (which is coupled to the rotary joint 105) from rotating with the rotary joint 105.

[0048] The device 100 may include an optional plate 108. The plate 108 may be coupled to and cover an end of the protective housing 102 (e.g., the second end 102c of the protective housing 102). In some embodiments, the plate 108 and the base 101 are coupled to opposite ends of the protective housing 102.

[0049] The plate 108 may be used as a support for the device 100. For example, the plate 108 may provide a flat surface on which the device 100 can rest stably on the bottom or floor of a volume of water. Various components of the device 100 may be coupled to the plate 108 to secure the components in place. For example, the bracket 107 may be coupled to the plate 108 with screws. In some embodiments, a non-rotating portion of the rotary joint 105 is coupled to the plate 108. Although shown generally circular in FIG. 1A, the plate 108 may have any shape. Various components of the device 100 may be located centrally or eccentrically on the plate 108. For example, the housing 102 and the bracket 107 may be located at the center of the plate 108. Although the plate 108 is shown in FIG. 1A as having a larger outer diameter than the housing 102, it may have the same outer diameter as the housing 102.

[0050] In some embodiments, the device 100 includes a drive mechanism that can rotate the rotatable permeable member 103. For example, the device 100 can include a motor 150 that includes a rotatable shaft 150a. For example, the device 100 can include a gearbox (not shown). The drive mechanism can be configured to rotate at a preset range of rotational speeds. The drive mechanism can be configured to rotate at several different preset ranges of rotational speeds (e.g., the rotational speed of the drive mechanism can be infinitely variable within the range), for example, the drive mechanism can include a variable speed drive. The drive mechanism can be submerged, partially submerged, or positioned above the liquid in which aeration is desired. In some embodiments, the motor 150 can be an electric motor, such as an AC motor, a DC motor, a stepper motor, or a servo motor. In some embodiments, the motor 150 is a battery-powered motor. In some embodiments, the device 100 includes a right-angle gearbox that allows the motor 150 to be mounted above a volume of liquid (e.g., a volume of water).

[0051] In some embodiments, the device 100 includes one or more impellers 150b coupled to a drive mechanism. Rotation of the one or more impellers 150b can induce a flow of liquid into and out of the tubular support 106 (thereby promoting circulation of the liquid) while nanobubbles are generated by the rotatable permeable member 103.

[0052] FIG 1B shows the device 100 shown in FIG 1A in an assembled form. A gas 140 (such as oxygen, an inert gas (e.g., nitrogen), ozone, or air) is provided to the inlet 104. The gas 140 may flow directly or indirectly from the inlet 104 to the rotatable permeable member 103 (shown in FIG 1A but blocked from view in FIG 1B by the perforated housing 102). Upon rotation of the rotatable permeable member 103, as the gas 140 flows through the pores of the rotatable permeable member 103, nanobubbles 140a are generated and dispersed in the liquid 120 that flows into and out of the tubular support 106 (shown in FIG 1A but blocked from view in FIG 1B) and the protective housing 102.

[0053] In some embodiments, the apparatus provided herein may operate in a medium containing a composition including a liquid, such as a slurry (e.g., a mixture of solids and liquids). Some non-limiting examples of liquid 120 include liquids including water (such as pond water, wastewater, or produced water) and cement slurries. The flow of liquid 120 into and out of the tubular support may be induced, for example, by the rotation of one or more impellers (not shown). Rotation of various components of the device 100 (such as the rotatable permeable member 103) may be provided by a drive mechanism, for example, a motor 150.

[0054] Figures 1C-1J show various views of device 100. Figure 1C shows a top view of device 100 in an assembled configuration. Figure 1D shows a side view of device 100 in an assembled configuration. Figure 1E shows a cross-section of the side view shown in Figure 1D. Figure 1F shows a side view of device 100 with housing 102 removed. Figure 1G shows a cross-section of the side view shown in Figure 1F. Figure 1H shows an exploded side view of device 100. Figure 1J shows a cross-section of the exploded side view shown in Figure 1H.

[0055] 1K is a top cross-sectional view of the rotatable permeable member 103 and tubular support 106 rotating within the protective housing 102. As gas 140 is injected into the rotatable permeable member 103 and exits the rotatable permeable member 103, nanobubbles 140a are formed at the exterior surface of the rotatable permeable member 103 by the gas 140 exiting the pores (103a, not shown) and shear forces in the surrounding liquid 120 that mimic turbulent flow above a turbulence threshold.

[0056] 2A-2D show various views of some optional non-rotating components of device 100, such as base 101, protective housing 102, and bracket 107. FIG. 2A shows a top perspective view of the non-rotating components of device 100 in an assembled configuration. FIG. 2B shows a bottom perspective view of the non-rotating components of device 100 in an assembled configuration. FIG. 2C shows a side view of the non-rotating components of device 100 in an assembled configuration. FIG. 2D shows a cross-section of the side view shown in FIG. 2C.

[0057] Figures 3A-3D show various views of several rotating components of device 100, such as rotatable permeable member 103 and tubular support 106. Figure 3A shows a top perspective view of the rotating components of device 100. Figure 3B shows a bottom perspective view of the rotating components of device 100. Figure 3C shows a side view of the rotating components of device 100. Figure 3D shows a cross section of the side view shown in Figure 3C. The tubular support 106 may advantageously direct liquid away from the rotatable permeable member to prevent coalescence of nanobubbles.

[0058] FIG 3E illustrates another example of a cylindrical support 106. The rotatable permeable member 103 may be located within the cylindrical support 106. The rotatable permeable member 103 (not shown) may pass through a central inner bore of the cylindrical support 106. FIG 3E illustrates another example of a cylindrical support 106. The cylindrical support 106 surrounds the rotatable permeable member 103. As shown in FIG 3E, the cylindrical support 106 may include one or more vanes.

[0059] FIG. 4 is a close-up view of the rotatable permeable member 103. The rotatable permeable member 103 defines a plurality of pores 103a through which gas 140 can exit and generate nanobubbles 140a. The pores 103a may have a diameter of 50 μm or less. In some embodiments, the pores 103a have a diameter ranging from 200 nm to 50 μm. The pores 103a may be uniform in size or may vary in size. The pores 103a may be uniformly or randomly distributed across the surface (e.g., outer surface) of the rotatable permeable member 103. The pores 103a may have any regular (e.g., circular) or irregular shape.

[0060] The rotatable permeable member 103 may be coupled to and rotated with a drive mechanism (not shown), such as a motor (150) coupled to a gearbox. Gas 140 flows into the rotatable permeable member 103. As the rotatable permeable member 103 rotates, the gas 140 exits through pores 103a, where the surrounding liquid (e.g., water) shears them under simulated turbulent conditions above a turbulence threshold, generating nanobubbles 140a dispersed in the surrounding liquid. The surrounding liquid 120 may be, for example, water, into which the introduction (e.g., aeration) of one or more gases is desired. During operation of the device 100, the rotatable permeable member 103 is preferably fully immersed in the liquid 120 such that all pores 103a are below the surface of the liquid 120.

[0061] In some embodiments, non-structural factors that can affect the size of the generated nanobubbles 140a, such as the composition of the gas 140 flowing into the rotatable permeable member 103, the rate at which the gas 140 flows into the permeable member 103, the supply pressure of the gas 140 flowing into the rotatable permeable member 103, the composition of the surrounding liquid 120, the flow rate (if any) of the surrounding liquid 120, and the pressure of the surrounding liquid 120.

[0062] As shown in Figures 5A-5C, the rotatable permeable member 103 may optionally include one or more radially extending features 110 to encourage flow of liquid along its surface. The radially extending features 110 are configured to direct liquid away from the outer surface of the body of the rotatable permeable member and to mimic turbulent flow above a turbulence threshold in the liquid that causes gas from the outer surface of the rotatable permeable member to shear into the liquid, thereby forming nanobubbles in the liquid. For example, in some embodiments, non-limiting examples of radially extending features 110 include wings (see Figure 5A), vanes (see Figure 5B), or propellers (see Figure 5C). The radially extending features may be fixedly coupled to (or integral with) the outer surface of the rotatable permeable member 103 to direct liquid away from the rotatable permeable member and prevent nanobubbles from coalescing. In certain such embodiments, the tubular support 106 may not be required to facilitate flow within the device, and is therefore optional.

[0063] In some embodiments, the radially extending features 110 may be coupled to the tubular support 106 and / or the rotatable permeable member 103 (eg, in a hub and spoke configuration).

[0064] FIG. 6 is a flow chart of a method 600 for liquid venting. The method 600 may be implemented, for example, using the venting device 100. In step 602, a liquid (e.g., the surrounding liquid 120) flows over a surface (e.g., an outer surface) of a rotatable permeable member (e.g., the rotatable permeable member 103). The liquid 120 may flow over the surface of the permeable member 103, for example, by immersing the rotatable permeable member 103 in the liquid 120. A perforated housing (e.g., the housing 102) may surround the rotatable permeable member 103. In some embodiments, when the rotatable permeable member 103 is immersed in the liquid 120, the flow of the liquid 120 may be induced, for example, by one or more rotating impellers. For example, the motor 150 may rotate one or more impellers to induce a flow of the liquid 120 in and out of the tubular support 106 surrounding the rotatable permeable member 103.

[0065] In step 604, a gas (e.g., gas 140) is flowed into the rotatable permeable member 103. The gas 140 may be flowed into the rotatable permeable member 103 by, for example, a blower or air pump connected to the air inlet 104. In some embodiments, the pressure of the gas 140 flowing into the rotatable permeable member 103 is at least 1 atmosphere (atm). In some embodiments, the pressure of the gas 140 flowing into the rotatable permeable member 103 is at most 10 atm. In some embodiments, the pressure of the gas 140 flowing into the rotatable permeable member 103 is in the range of 1 atm to 10 atm, or 2 atm to 8 atm. In some embodiments, the pressure of the gas 140 flowing into the rotatable permeable member 103 is in the range of 7 atm to 8 atm.

[0066] In step 606, the rotatable permeable member 103 is rotated to generate nanobubbles (e.g., nanobubbles 140a) from the gas 140 and expel the generated nanobubbles 140a into the liquid 120 around the surface of the rotatable permeable member 103. The rotatable permeable member 103 may be rotated in step 606 by a drive mechanism such as the rotating shaft 150a of the motor 150 or a gear box. The cylindrical support 106 rotates with the rotatable permeable member 103. The rotatable permeable member 103 (and the cylindrical support 106) may be rotated in step 606 at a rotational speed that mimics turbulence above a turbulence threshold of the surrounding liquid 120 at the surface of rotation of the rotatable permeable member 103 to form nanobubbles.

[0067] FIG. 7 is a flow chart of a method 700 for liquid venting. The method 700 may be implemented, for example, using the venting device 100. In step 702, at least a portion of a rotatable permeable member (e.g., the rotatable permeable member 103) is immersed in a liquid (e.g., the surrounding liquid 120). As previously described, the rotatable permeable member 103 is disposed within a housing 102 defined by an outer wall 102a extending between a first end 102b and a second end 102c. The housing 102 defines a plurality of perforations 102d in its outer wall 102a to facilitate the flow of liquid into and out of the housing. In some embodiments, the tubular support 106 may define a plurality of vanes or blade structures (see, for example, FIGS. 3E and 3F) to facilitate the flow of liquid into and out of the rotatable permeable member 103. The rotatable permeable member 103 is coupled to a rotatable shaft 150a of a motor 150. In step 704, a gas (such as gas 140) is introduced into the rotatable permeable member 103, either directly or indirectly, through an inlet (e.g., inlet 104). In step 706, a rotatable shaft 150a coupled to the rotatable permeable member 103 is rotated, thereby generating nanobubbles (e.g., nanobubbles 140a) from the gas 140. In various embodiments, rotating the rotatable shaft 150a in step 706 includes rotating the rotatable permeable member 103 (and tubular support 106) at a rotational speed that mimics above-threshold turbulence flow of the surrounding liquid 120 at the surface of the rotatable permeable member 103 (similar to step 606 of method 600).

[0068] Any of the devices (or apparatus) and methods described herein include generating nanobubbles having an average diameter of less than 1 μm in a liquid volume (e.g., a volume of water). In some aspects, the nanobubbles have an average diameter ranging from about 10 nm to about 500 nm, about 75 nm to about 200 nm, or about 50 nm to about 150 nm. The nanobubbles in the composition may have a unimodal diameter distribution with an average bubble diameter of less than 1 μm. In some embodiments, any of the compositions generated by the devices (or apparatus) and methods described herein include nanobubbles but do not include microbubbles.

[0069] The devices (or apparatus) and methods described herein include generating a high concentration of nanobubbles dispersed in the liquid volume exiting the device. In some embodiments, the devices (or apparatus) and methods described herein generate at least 1×10 nanobubbles. 6 / ml, at least 1×10 nanobubbles 7 / ml, or at least 1 x 10 nanobubbles 8 The present invention relates to a method for producing nanobubbles in a liquid carrier, the method comprising: generating a high concentration of nanobubbles at the outlet of the liquid carrier, the high concentration being nanobubbles per ml. The apparatus and methods provided herein can produce compositions containing nanobubbles in a liquid carrier that remain stable for a desired period of time. In some embodiments, the compositions provided herein contain nanobubbles that are stable in a liquid carrier under ambient pressure and temperature for at least one month, preferably at least three months.

[0070] Specific embodiments of the subject matter have been described. It will be understood that various modifications, substitutions, and alterations may be made. Although operations are depicted in a particular order in the drawings or claims, this should not be understood as requiring such operations to be performed in the particular order shown, or in the sequential order, or to perform all of the operations shown, in order to achieve desirable results (some operations may be considered optional). Thus, the exemplary embodiments described above do not define or limit the present disclosure.

Claims

1. a motor including a rotatable shaft; An axially rotatable permeable member including a body having a wall and a plurality of pores, a gas introduced into the axially rotatable permeable member is capable of flowing through the plurality of pores; the axially rotatable permeable member is coupleable to an inlet configured to introduce gas from a gas source into the axially rotatable permeable member; the axially rotatable permeable member is coupled to a rotatable shaft of the motor and adapted to rotate with the rotatable shaft; the axially rotatable permeable member; and A rotatable tubular support including an elongated body, the elongated body having a wall and defining an interior cavity; the wall defines a plurality of perforations; the interior cavity of the rotatable tubular support is configured to accommodate the axially rotatable permeable member; the rotatable tubular support is coupled to a rotatable shaft of the motor for rotation therewith; When rotated, the rotatable tubular support is adapted to introduce liquid into the interior cavity of the rotatable tubular support and to move liquid away from an exterior surface of a body of the rotatable permeable member; When rotated, the axially rotatable permeable member is adapted to mimic turbulence above a turbulence threshold in the liquid, causing gas from an outer surface of the axially rotatable permeable member to shear into the liquid, thereby forming nanobubbles in the liquid. The rotatable cylindrical support 1. An apparatus for generating nanobubbles in a volume of liquid, comprising:

2. 10. The apparatus of claim 1, wherein the axially rotatable permeable member is coupled to the rotatable tubular support such that the axially rotatable permeable member is positioned concentrically within the rotatable tubular support.

3. 3. The apparatus of claim 1 or claim 2, wherein the perforations in the rotatable tubular support are circular, semicircular, rectangular, cubic, elliptical, triangular, or slot-shaped.

4. Further comprising a base and a housing; the housing is defined by an exterior wall extending between a first end and a second end coupled to the base, the exterior wall defining a plurality of perforations, and an axially rotatable permeable member and a rotatable tubular support are disposed within the housing.

4. The device according to claim 1.

5. 5. The apparatus of claim 4, wherein the housing is fixed to the base so that it cannot rotate.

6. further comprising an impeller disposed within the housing; the impeller adapted to induce a flow of liquid into and out of the housing and away from a surface of an axially rotatable permeable member; 6. The device according to claim 4 or 5.

7. 7. The apparatus of any one of claims 1 to 6, wherein the axially rotatable permeable member has a circumference defined by an outer diameter sized to mimic turbulent flow above a turbulence threshold of the liquid.

8. 8. The device of claim 1, wherein the pores of the rotatable permeable member have a diameter in the range of 200 nm to 50 μm.

9. 8. The device of claim 1, wherein the pores of the rotatable permeable member have a diameter of 50 μm or less.

10. 10. The device of any one of claims 1 to 9, wherein the nanobubbles have an average diameter of less than 500 nm.

11. The device of any one of claims 1 to 10, wherein the nanobubbles have an average diameter of less than 200 nm.

12. The device of any one of claims 1 to 11, wherein the nanobubbles have an average diameter in the range of about 10 nm to about 500 nm.

13. The device of any one of claims 1 to 12, wherein the nanobubbles have an average diameter in the range of about 75 nm to about 200 nm.

14. A method for generating nanobubbles in a volume of liquid using a device according to any one of claims 1 to 13, comprising the steps of: immersing at least a portion of the device in a liquid; introducing gas from a gas source through an inlet into the axially rotatable permeable member at a gas pressure that forces the gas through a plurality of pores in the axially rotatable permeable member; and Rotating the rotatable tubular support and the axially rotatable permeable member such that the liquid shears gas from an outer surface of the axially rotatable permeable member to mimic turbulence above a turbulence threshold in the liquid, thereby forming nanobubbles.

15. 15. The method of claim 14, wherein the pressure of the gas entering the axially rotatable permeable member is between about 1 atmosphere and about 10 atmospheres.

16. A method for treating water, comprising the steps of:

14. Using the apparatus of any one of claims 1 to 13, generating nanobubbles dispersed in a volume of liquid including a source of water requiring treatment.

17. a motor including a rotatable shaft; An axially rotatable permeable member including a body having a wall and a plurality of pores, a gas introduced into the axially rotatable permeable member is capable of flowing through the plurality of pores; the axially rotatable permeable member further includes at least one radially extending member; the axially rotatable permeable member is coupleable to an inlet configured to introduce gas from a gas source into the axially rotatable permeable member; the axially rotatable permeable member is coupled to a rotatable shaft of the motor and adapted to rotate with the rotatable shaft; the axially rotatable permeable member Including, When rotated, the axially rotatable permeable member to direct liquid away from an exterior surface of the body of the axially rotatable permeable member; and shearing gas from an outer surface of the axially rotatable permeable member into a liquid to mimic turbulence above a turbulence threshold in the liquid; adapted to form nanobubbles in the liquid. A device for generating nanobubbles in a volume of liquid.

18. The method of claim 17 , wherein the radially extending members comprise one or more blades, vanes, propellers, or combinations thereof.

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