WO2013151914A1 - Système pour former des mini microbulles - Google Patents

Système pour former des mini microbulles Download PDF

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Publication number
WO2013151914A1
WO2013151914A1 PCT/US2013/034761 US2013034761W WO2013151914A1 WO 2013151914 A1 WO2013151914 A1 WO 2013151914A1 US 2013034761 W US2013034761 W US 2013034761W WO 2013151914 A1 WO2013151914 A1 WO 2013151914A1
Authority
WO
WIPO (PCT)
Prior art keywords
plate
housing
shaft
motor
disk
Prior art date
Application number
PCT/US2013/034761
Other languages
English (en)
Inventor
Thomas St. Lawrence
Original Assignee
St Lawrence Thomas
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US13/437,507 external-priority patent/US8740193B2/en
Application filed by St Lawrence Thomas filed Critical St Lawrence Thomas
Publication of WO2013151914A1 publication Critical patent/WO2013151914A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
    • B01F23/23313—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements through a separate conduit substantially parallel with the stirrer axis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2334—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements provided with stationary guiding means surrounding at least partially the stirrer
    • B01F23/23341—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements provided with stationary guiding means surrounding at least partially the stirrer with tubes surrounding the stirrer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2335—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the direction of introduction of the gas relative to the stirrer
    • B01F23/23353—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the direction of introduction of the gas relative to the stirrer the gas being sucked towards the rotating stirrer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2336—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the location of the place of introduction of the gas relative to the stirrer
    • B01F23/23363—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the location of the place of introduction of the gas relative to the stirrer the gas being introduced above the stirrer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/05—Stirrers
    • B01F27/07—Stirrers characterised by their mounting on the shaft
    • B01F27/071—Fixing of the stirrer to the shaft
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/05—Stirrers
    • B01F27/11—Stirrers characterised by the configuration of the stirrers
    • B01F27/115—Stirrers characterised by the configuration of the stirrers comprising discs or disc-like elements essentially perpendicular to the stirrer shaft axis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/05—Stirrers
    • B01F27/11—Stirrers characterised by the configuration of the stirrers
    • B01F27/115—Stirrers characterised by the configuration of the stirrers comprising discs or disc-like elements essentially perpendicular to the stirrer shaft axis
    • B01F27/1152—Stirrers characterised by the configuration of the stirrers comprising discs or disc-like elements essentially perpendicular to the stirrer shaft axis with separate elements other than discs fixed on the discs, e.g. vanes fixed on the discs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/25—Mixers with both stirrer and drive unit submerged in the material being mixed

Definitions

  • the present, invention relates to systems having optional delivery of multiple and mixed- phase media into liquids using partial vacno control.
  • the present invention relates to systems that Form mini microbubbles.
  • the present invention relates to aeration systems.
  • the present invention relates to enhancing the biological treatment of liquids.
  • [0O02J Mixing, by introducing media, such as a gas or a solid or a liquid or a combination thereof, to a liquid is a common practice when treating liquids such as fresh water, salt water and all types of waste water .
  • aeration by the introduc tion of atmospheric air containing oxygen into water is one o f the most common methods used to biological ly support the aerobic treatment of these liquids. Aerobic treatment of carbonaceous waste requiring an adequate supply of oxygen is much more efficient tha anaerobic treatment of carbonaceous waste.
  • ⁇ 0004J Aerators are used to treat a wide variety of liquids and liquid volumes for a wide variety of applications. Examples of such uses include treating aquariums, septic tanks, ponds, process tanks, municipal treatment plants, lagoons, streams, lakes and oceans.
  • a rami microbiibble is smaller than a microbiibble, remains in liquid longer than a ierohubble, and imparts a milky appearance to liquids.
  • Mini inicrohubbies easily flow, rapidly diffuse, and linger within a liquid.
  • Mint mierobubbles also have more surface area than larger bubbles-. Because gas transfer to liquids is a function of the ratio of surface area to volume, the smaller mini microbobbles have a greater transfer potential and are better for aeration. Thus, there is a need for systems that can create mini mierobubbles for the treatment of a liquid.
  • a quantity of gas, such as air, that is released into water under a partial vacuum creates an unstable bubble, termed, a "vacuum bubble,” which rapidly adjusts its volume until its pressure reaches equilibrium.
  • a system for precisel controlling the size, quality and quantity of gas bubbles by using the partial -vac uum variables of pressure and volume based the Gas La P I V I ⁇ P2V2 is needed.
  • U.S. Patent No. 5,194,144 issued, on March 16, 1993 to B lough, discloses an improved aeration device fo septic tanks which allows fi ne bubbles of air to aerate waste material i n the tank so that aerobi c bacteria ma fully perform, their decomposing function.
  • Air enters the upper end of a shaft and exists adjacent, a propeller.
  • the propeller is protected From interfering with its bubble formation action by a guard bushing concentrically positioned in the air tube so that typical non-organic waste adulterants, such is plastic and rubber materials that are often found in septic tanks, are not drawn into the propeller to interfere with its action.
  • U.S. Patent No. 5.67(>,S99, issued on October 14, 1997 to Belgln discloses an apparatus for aerating and mixing liquids and .gases that includes a hollow housing, at least one rotating object, a rotating apparatus for rotating the rotating, object, a. shaft, and at least one adjustably positioned conduit tube.
  • the hollow housing has a first portion and a second portion.
  • the first portion has a wall that contains at least one port and the second portion has a wall that contains at least one outflow port.
  • the rotating object is located in the second portion and has. a low-pressure side.
  • the rotating apparatus rotates the rotating object, and is located in the first portion.
  • the shaft connects the rotating object to the rotating apparatus.
  • the adjustahly-positioned conduit tube passes through the inflow port and has a first end externally located from the hollow housing.
  • the conduit tube also has a second end located in the low-pressure side so thai, upon rotation of the rotating object, a. substanc can be drawn from the first end to the low-pressure, side.
  • U.S. Patent No. 6,245,237 issued on June 1.2, 2001 to B lough et al., discloses an improved method- for aeration of septic tanks and the lik by drawing ' atmospheric, air into an expansion chamber and, from there, into agitated sludg to provide low-pressure small mierobuhbles which have long hold times in the sludge material.
  • U.S. Patent No. 6.254,066, issued, on July 3 2001 to Drewery discloses an apparatus for aerating liquid in a wastewater treatment tank having a submergible motor with a shaft, extending outwardly therefrom, a supporting roeniber affixed to the ubmergible motor and adapted to maintain the -submergible motor in a position within the liquid in the wastewater treatment tank, a propeller affixed to the shaft of the submergible motor, a housing extending around the propeller and the shaft, and an air tube connected to the housing and adapted to pass air interior of the ho using between the propeller and th motor.
  • the housing has a tubular configuration with a.
  • the housing will extending beyond an end of the propeller opposite the shaft.
  • the air tube extends so as to have one end affixed, to the housing and communicate with an interior of the housing at an opposite end opening to an area outside of the liquid, in the wastewater treatment tank.
  • U.S. Patent No. 6,461 ,500 issued on October 8, 2002 to Hoage et al., discloses an improved method and apparatus for aera tion of septic tanks and the like. Because of the interrelations hi of the rotating impeller, an air plate, and the horsepower of the. unit in comparison with the volumetric size of the sludge tank, the unit disperse extremely small reduced-pressure mierobubbJes adjacent the area of the impeller. These reduced pressure. tmcrobubbles are thereafter dispersed throughout the wastewater by Brownian. movement without agitating the sludge. As a. result, there, is Substantially increased lateral oxygen ' transfer to replace the oxygen used by the aerobic- bacteria. The sludge is therefore efficiently digested without the need for huge, expensive and energy- inefficient equ ⁇
  • U.S. Patent No. 7,306,722 issued on December 1 1 , 2007 to Boage, discloses an improved apparatus and method to increase la teral oxygen trans fer in waste wa ter which eliminates -rotating impellers and air plates. As a result, less horsepower per unit can be used to achieve smaller entrained air bubbles resulting in increased residence time and enhanced lateral oxygen transfer to replace oxygen consumed by aerobic bacteria during the biodegiadatioii process. It may be used on industrial waste water sources of a! types which are biodegradable by aerobic bacteria.
  • the drive means serves to rotate the shaft.
  • the plate is positioned inwardly of the lower end of the hoasmg.
  • the bousing has an annular wall at the lower end.
  • the plate lias a outer periphery adjacen t this annular wall.
  • the drive means is a . submersible motor.
  • the housing has a support surface adjacent the lower end.
  • the shaft extends through this support surface.
  • the air line opens to space between the plate and the support, surface.
  • the plate extends in a horizontal plane inwardl of the lower end of the housing.
  • the lower surface of the plate is smooth.
  • the upper surface is also smooth.
  • the upper surface can have .ridges formed therein.
  • the plate is in the nature of a disk. This disk has a clamp affixed thereto. The clam serves to secure the disk to the shaft.
  • FIG URE 1 shows a side cross-sectional view of the system of the pre sent invention as uti ! ized in water.
  • FIGURE 2 is a cross-sectional view of the system of the present invention.
  • FIGURE 3 is a cross-sectional view showing the connection between the plate and the shaft.
  • FIGURE 4 is a bottom view showing the plate of the present invention.
  • FIGU RE 5 is a top view showing the plate of an alterative embodiment of the present invention.
  • FIG URE I there is shown the system 1 f ) for the forming of mi ni microbubbles.
  • the system 10 is employed in a body of water 12.
  • this body of water 12 can be a liquid that is being aerohieaiiy treated.
  • the system 10 of the present invention includes a housing 14 having an upper end 16 and a Sower end 18.
  • An electrical line 20 extends to the housing 14. so as to. provide power for the drive means located within the housing 14.
  • An ai line. 22 has one end 24 affixed to the housing 14 generally adjacent the lower end 18 thereof.
  • the air line 22 extends so as to have another end 26 located above the body of water 12 or connected to a source of air.
  • mint microbabbles 2S will be released from the lower end 18 of the housing 14, in the manner described hereinafter.
  • FIGURE 2 it .can be see that a mo t or 30 is recei ved w i thin an interior 32 of housin g 14.
  • the motor 30 is in the nature of a submersible motor.
  • the electrical line 20 is connected to the motor 30 and extends outwardl of the housing .14.
  • the motor 3.0 has a shaft 36 extending downwardly therefrom. Shalt 36 extends through bearings formed in the support surface 34 or otherwise through the support surface 34.
  • a plate 38 Is affixed to the shaft 36 in a position generally adjacent to the lower end 1.8 of the .housing 14.
  • the plate 38 extends radially outwardly of the shaft 36.
  • the lower end 1.8 of the housing 14 has an annular all 40 formed therein.
  • the periphery of the plate 38 will be adjacent, to the annular wall 40.
  • the piate 38 extends in a generally horizontal plane and in a recess inwardly of the lower end 18 of the housing 14,
  • the air l ine 22 has the end 24 opening to the space 42 between the upper surface of the plate 38 and the support surfac 34. As such, ait will enter the space 4:2 during the rotation of the plate 38.
  • FIGURE 3 shows how the plate 38 is secured to the shaft 36.
  • a clamp 44 is affixed to the plate 38, Clamp 44 will extend around the .shaft 36.
  • a set screw' .46 can be utilised so as to fix the clamp 44 to the exterior surface of the shaft 36, As such, the plate 8 is securely mo nted on the shaft 36.
  • FIGURE 4 Shows a bottom view of the plate 38. It can he seen that the plate 38 is a disk having an entirel smooth lower surface 48. The clamp 44 is positioned centrally of the plate 38.
  • FIGURE 5 shows an alternative embodiment of the piate 38 and shows, in particular, a different ' arrangement of the upper surface 50 of plate 38.
  • the plate 38 has generally smooth upper surface.
  • FIGURE S it. can he seen that there are ridges 52 formed on this upper surface 50 of plate 38. Ridges 52 can be in the nature of vanes that extend upwardly in a generally arcuate fashion. It is believed, that it is possible that the use of such ridges 52 enhances the turbulent nature of the air flow passing to the upper surface 50 .from the air line 22,
  • the smooth plate 3 creates a partial vacuum in the area between, the space 42.
  • The. rotation of the plate 3.8 causes, water to spin out and slam against the annular wall 40. This creates the requisite turbulence for the formation of the mini icrohubbles.
  • the surfaces of the plate 38 entirely are smooth, there are no possibility of the accumulation of material in holes, vanes, or other areas .formed on the surface of the blades,.
  • the mini mi.crobubbl.es can be produced by the system 10 of the present .invention without interruption, maintenance, or repair. j0047
  • the system 10 of the present invention is novel because the system 10 can be conveniently adjuste for bubble quality (e.g.
  • the distance between the support surface 34 and the plate 3.8 can he adjusted. This distance defines the equalization area where media mixed with the liquid due to the turbulence created by the plate 38. It is a the depth of this area that bubbles form and then are released .into the liquid around the periphery of the plate 38 adjacent to the annular wail 40.
  • This seemingly instantaneous collapse, invaeination of bubbles to a point of pressure equalisation is in direct response to the pressure of the liquid in the equalization area. Invaeination is the process in which a gas is introduced into a liquid and specifically refers to the point where the pressure inside a bubble equals the pressure of the liquid surrounding the bubble.
  • the m dia passing into the equalization area presents a unique opportunity to control ultimate bubble size.
  • the milky appearance of resulting mini mierobubbles Is example of such control.
  • the gas between the annular wail 40 and the periphery of the plate 38 is the primary lateral point of release foriheliquid itTamedwim Lateral release in this particular area can be useful and desirable for reasons such as added mixing, excluder purging and directional discharging and recovery to and from remote areas.
  • the depth of deployment to of the system 10 below the .surface of the body of water 12 can be adjusted.
  • the position of the housing 14 and the motor 30 can be adjusted vehicle upwardly or vehicle downwardly. It can also be angled in a desired direction.
  • the medi flo and partial vacuum can be adjusted to reach a desired bubble si3 ⁇ 4e.
  • a temporary transparent, connection e.g. clear tubing
  • a partial pressure can be measured in real time.
  • the partial vacuum range can be selected and adjusted until a desired bubble size is generated.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Aeration Devices For Treatment Of Activated Polluted Sludge (AREA)

Abstract

L'invention concerne un système (10) pour former des mini microbulles qui présente un boîtier (14) avec une extrémité supérieure (16) et une extrémité inférieure (18), un moteur (30) positionné dans le boîtier, un arbre (36) relié au moteur, une plaque (38) fixée à l'arbre et s'étendant radialement en dehors de celui-ci, et une conduite d'air (22) connectée au boîtier (14) de manière à s'ouvrir dans un espace dans le boîtier adjacent à l'extrémité inférieure de celui-ci entre la plaque et le moteur. La plaque (38) est positionnée vers l'intérieur de l'extrémité inférieure du boîtier. La plaque a une surface inférieure lisse. Le moteur (30) est un moteur submersible.
PCT/US2013/034761 2012-04-02 2013-04-01 Système pour former des mini microbulles WO2013151914A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US13/437,507 2012-04-02
US13/437,507 US8740193B2 (en) 2008-05-23 2012-04-02 System for forming mini microbubbles

Publications (1)

Publication Number Publication Date
WO2013151914A1 true WO2013151914A1 (fr) 2013-10-10

Family

ID=49300963

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2013/034761 WO2013151914A1 (fr) 2012-04-02 2013-04-01 Système pour former des mini microbulles

Country Status (1)

Country Link
WO (1) WO2013151914A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07114947B2 (ja) * 1988-07-08 1995-12-13 新明和工業株式会社 水中曝気装置
WO1996034680A1 (fr) * 1995-05-01 1996-11-07 Keepalive, Inc. Aerateur et procede d'aeration
KR100806474B1 (ko) * 2006-02-20 2008-02-21 한상배 교반장치와 이를 이용한 수중포기기
US20090213684A1 (en) * 2007-10-25 2009-08-27 Midan Industries Ltd. Apparatus for distribution of a gas into a body of liquid
JP2011140016A (ja) * 2009-12-11 2011-07-21 Mg Grow Up:Kk 混合撹拌装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07114947B2 (ja) * 1988-07-08 1995-12-13 新明和工業株式会社 水中曝気装置
WO1996034680A1 (fr) * 1995-05-01 1996-11-07 Keepalive, Inc. Aerateur et procede d'aeration
KR100806474B1 (ko) * 2006-02-20 2008-02-21 한상배 교반장치와 이를 이용한 수중포기기
US20090213684A1 (en) * 2007-10-25 2009-08-27 Midan Industries Ltd. Apparatus for distribution of a gas into a body of liquid
JP2011140016A (ja) * 2009-12-11 2011-07-21 Mg Grow Up:Kk 混合撹拌装置

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