JP2018089610A - Fine bubble generation nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fine bubble generation nozzle for largely enhancing a generation rate of a fine bubble of a micro-level and a nano-level.SOLUTION: A fine bubble generation nozzle 1 is provided with an introduction chamber 20 for introducing a gas-liquid mixed body, a turning chamber 30 for turning the gas-liquid mixed body L flowed out of the introduction chamber 20, a derivation flow passage 61 for deriving the turned gas-liquid mixed body L, a branch flow passage 62 for branching off from the derivation flow passage and a circulation flow passage 66 for circulating the gas-liquid mixed body L of reaching the downstream side of the derivation flow passage to the upstream side of the derivation flow passage 61 without flowing in the branch flow passage. According to this nozzle 1, since a fine bubble is generated by circulating the gas-liquid mixed body L of not generating the fine bubble, the fine bubble can be generated in large quantities.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fine bubble generating nozzle that generates fine bubbles by a swirling flow method.

  Conventionally, as an example of a swirl flow type fine bubble generating nozzle, there is one disclosed in Patent Document 1. A conventional fine bubble generating nozzle has an inlet for introducing liquid at one end and a gas from an intake port opened on the peripheral wall of the casing body into a cylindrical casing body having an outlet for discharging liquid at the other end. The gas-liquid mixing part which introduces and mixes with the liquid and the swirl flow formation part which makes a gas-liquid mixture turn into a swirl flow are provided. The gas-liquid mixture that has turned into a swirl is subjected to a force that is repelled sideways by the influence of strong rotation when released, and the gas is divided by the action of twisting and pulling as the vortex breaks down. By being divided in this manner, fine bubbles are generated.

  Further, as a development of a swirl flow type fine bubble generating nozzle, there is one disclosed in Patent Document 2. This fine bubble generating nozzle is intended to generate more fine bubbles by circulating and shearing the gas-liquid mixture in which the fine bubbles are generated by the swirling flow method.

JP 2007-21343 A Japanese Patent No. 4678617

  However, since the fine bubble generating nozzle shown in Patent Document 1 merely generates a fine bubble using a shearing force when a swirling flow is discharged, it is micro level (several tens to several hundreds μm) and nano level ( There was a problem that a large amount of fine bubbles (less than 1 μm) could not be generated. Moreover, since the gas-liquid mixture cannot actually circulate the fine bubble generating nozzle shown in Patent Document 2, there is a problem that a large amount of fine bubbles cannot be generated.

  The present invention has been created in view of the above problems, and an object of the present invention is to provide a fine bubble generating nozzle that greatly increases the generation ratio of micro-level and nano-level fine bubbles.

  An introduction chamber for introducing the gas-liquid mixture, a swirl chamber for turning the gas-liquid mixture flowing out from the introduction chamber, a lead-out channel for leading out the swirled gas-liquid mixture, and a branch branched from the lead-out channel The fine bubble generating nozzle includes a flow path and a circulation flow path that circulates the gas-liquid mixture that has reached the downstream of the discharge flow path without flowing into the branch flow path to the upstream of the discharge flow path.

  The circulation channel is an inner hole of a cylindrical member, and the cylindrical member is inserted into the outlet channel, and the outlet channel and the cylindrical shape are formed on the outer peripheral surface of the downstream end of the cylindrical member. An inlet hole that communicates with the inner hole of the member and introduces the gas-liquid mixture that has reached the downstream of the outlet channel into the inner hole of the cylindrical member is formed, and the outer peripheral surface of the upstream end of the cylindrical member Preferably, the outlet channel and the inner hole of the cylindrical member communicate with each other, and an outlet hole for leading the gas-liquid mixture that flows back through the inner hole of the cylindrical member to the upstream side of the outlet channel is preferably formed.

  Moreover, it is preferable that the branch flow path is formed so that the opening area of the outlet is wider than the opening area of the inlet. Furthermore, it is preferable that one side surface of the branch channel is a curved surface, and the side surface facing this is a flat surface.

  Moreover, it is preferable that a core is disposed inside the swirl chamber, and a swirl flow path formed on the surface swirls the gas-liquid mixture.

  The inner surface of the swirling channel is preferably formed in a step shape.

  ADVANTAGE OF THE INVENTION According to this invention, the micro bubble production | generation nozzle which can generate | occur | produce a large quantity of micro level and nano level micro bubbles can be provided.

It is a longitudinal cross-sectional view of the front view in the fine bubble generating nozzle of this invention. It is a perspective view from the plane side showing the internal structure of the swirl chamber in the fine bubble generating nozzle of the present invention. It is a perspective view from the bottom side showing the internal structure of the swirl chamber in the fine bubble generating nozzle of the present invention. It is a perspective view from the plane side which shows the internal structure of the shear chamber in the fine bubble generation | occurrence | production nozzle of this invention. It is a figure which shows the internal pressure of each flow path in the fine bubble generation nozzle of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes a fine bubble generating nozzle, which has a nozzle body 10 composed of a first body 11 and a second body 12. Inside the nozzle body 10, an introduction chamber 20 for introducing the gas-liquid mixture L, a swirl chamber 30 for turning the gas-liquid mixture L in a swirl flow, and the gas-liquid mixture L in a swirl flow are sheared. A shear chamber 50 for generating fine bubbles is formed.

  The introduction chamber 20 is provided with an introduction port 21 at one end, from which the gas-liquid mixture L is introduced. Further, the introduction chamber 20 is formed so that the inner diameter becomes smaller toward the downstream side, and the swirl chamber 30 communicates therewith.

  The inner diameter of the swirl chamber 30 is formed so as to gradually increase from the portion communicating with the introduction chamber 20 to the intermediate point and gradually decrease from the intermediate point to the outlet 31. A core 40 is disposed inside the swirl chamber 30. The core 40 is formed in a substantially conical shape (specifically, a chestnut shape) and has an outer shape along the inner wall of the swirl chamber 30. The core 40 is disposed so as to be fitted inside the swirl chamber 30 so that the top portion 42 of the core 40 faces the upstream side.

  As shown in FIG. 2, on the side surface 41 of the core 40, blade portions 43a that turn clockwise at a predetermined turning angle protrude, and six similar blade portions 43a are arranged at equal intervals. ing. And the turning flow path 43 is formed of the clearance gap between the adjacent blade | wing parts 43a.

  The swirl flow path 43 includes a bottom surface 43b, an inner side surface 43c, and an outer side surface 43d. When the core 40 is disposed inside the swirl chamber 30, the opening portion facing the bottom surface 43b is swirled. It is closed by the inner wall of the chamber 30. In short, the side swirl flow path 43 is constituted by the bottom surface 43 b, the inner side surface 43 c, the outer side surface 43 d, and the four surfaces of the inner wall of the swirl chamber 30. With such a configuration, the swirl flow path 43 generates a velocity component in the swirl direction for the gas-liquid mixture L that has flowed into the swirl chamber 30, as indicated by a two-dot chain line in FIG.

  Of the inner surface of the swirl passage 43, the bottom surface 43b and the outer side surface 43d are formed in a step shape so as to descend in the direction in which the gas-liquid mixture L flows so as to generate a vortex in the step portion. It is configured. Similarly, the inner wall 33 of the swirl chamber 30 is also formed in a step shape.

  Further, the inlet A and the outlet B of the swirling channel 43 are configured such that the groove depth of the inlet A is deeper than the groove depth of the outlet B, and the opening area of the inlet A is larger than the opening area of the outlet B. Yes.

  As shown in FIG. 3, blade portions 45 a and 45 b that project clockwise at a predetermined turning angle project from the bottom surface 44 of the core 40 when viewed from the bottom. The blade 45a and the blade 45b have different turning angles, and six downstream blades 45a and 45b having different turning angles are alternately arranged at a predetermined interval. A swirl flow path 45 as a flow path of the gas-liquid mixture L is formed by a gap between the adjacent downstream blade section 45a and the downstream blade section 45b.

  When the core 40 is disposed inside the swirl chamber 30, the swirl flow path 45 is configured such that the opening portion facing the bottom surface 44 is closed by the inner wall of the swirl chamber 30. For this reason, the gas-liquid mixture L flows in the swirling flow path 45 as shown by a two-dot chain line in FIG. It is comprised so that the speed component of a turning direction may be produced. Thus, the swirl flow path 45 is formed in the swirl chamber 30 by the swirl flow path 43 formed on the side surface 41 of the core 40 and the swirl flow path 45 formed on the bottom surface 44 of the core 40. Has been.

  As shown in FIGS. 1 and 4, a shear member 60 formed by laminating a plurality of members is disposed inside the swirl chamber 50. The shearing member 60 is formed in a bottomed hollow cylindrical shape, and the bottomed hollow hole is a lead-out flow path 61, and the opening portion communicates with the lead-out port 31 of the swirl chamber 30. The shearing member 60 is formed with a branching channel 62 that branches from the outlet channel 61 and extends to the outer peripheral surface of the shearing member 60.

  Six branch passages 62 are provided in a line at equal intervals in the circumferential direction, and a total of 18 branch paths 62 are formed by providing three lines. In the drawings, for convenience, the part numbers of all the branch flow paths are indicated as 62. As shown in FIG. 4, the branch channel 62 includes an inlet 62 a that communicates with the outlet channel 61 and an outlet 62 b that opens to the outer peripheral surface of the shear member 60. Is configured to gradually expand from the inlet 62a to the outlet 62b. Furthermore, on both side surfaces of the branch flow path 62, one side surface is a curved surface 62c, and the other side surface facing this is formed on a flat surface 62d. The branch flow path 61 configured as described above increases the generation ratio of fine bubbles.

  As shown in FIG. 1, the shear member 60 is disposed inside the swirl chamber 50 with a predetermined interval between the outer peripheral surface thereof and the inner wall of the swirl chamber 50. A discharge channel 63 is formed by a gap with the outer peripheral surface of the shearing member 60. A bubble cutting panel 64 having a plurality of holes is wound around the outer peripheral surface of the shearing member 60. Further, the shearing member 60 is held by a lid 70, and the lid 70 is attached to the end of the nozzle body 10. The lid 70 has a large number of discharge holes 71 communicating with the discharge flow path 63. For this reason, the gas-liquid mixture L flowing out from the outlet 62 b of the branch flow path 62 passes through the hole of the bubble cutting panel 64, flows into the discharge flow path 63, and is ejected from the discharge hole 71.

  On the other hand, a circulation pipe 65, which is a hollow cylindrical tubular member that opens at both ends, is inserted into the outlet channel 61. This hollow hole is the circulation channel 66. However, the circulation pipe 65 has one end closed by the bottom surface of the bottomed hollow hole of the shearing member 60 (that is, the most downstream portion of the outlet channel 61) and the other end closed by the bottom surface of the core 40. It is disposed in the path 61. Further, the circulation pipe 65 is disposed inside the outlet channel 61 with a gap between the outer peripheral surface thereof and the inner wall of the outlet channel 61, and the gas-liquid mixture L flows through this gap.

  In the circulation pipe 65, four inlet holes 66a are formed at equal intervals on the outer peripheral surface of the downstream end, and similarly, four outlet holes are formed on the outer peripheral surface of the upstream end at equal intervals. 66b is formed. The inlet hole 66 a and the outlet hole 66 b communicate the outlet channel 61 and the circulation channel 66.

  The basic operation and operation effect of the fine bubble generating nozzle configured as described above will be described.

  The gas-liquid mixture L introduced from the introduction port 21 flows through the introduction chamber 20 and flows into the swirl chamber 30. At this time, the gas-liquid mixture L becomes a high-speed swirl flow by flowing through the swirl flow channel 45 subsequent to the swirl flow channel 43. Further, the inner surfaces of the swirling flow path 43 and the swirling flow path 45 are stepped, so that a small vortex flow is generated. Since the frictional resistance between the gas-liquid mixture L and the swirling flow path 43 and the swirling flow path 45 is reduced by this vortex flow, the gas-liquid mixture L becomes a higher-speed swirling flow. In addition, since the swirl flow path 43 is configured so that the opening area gradually decreases from the inlet A to the outlet B, the size of the vortex generated in the swirl flow path 43 becomes very small, and the effect of reducing frictional resistance is achieved. Can be increased.

  The gas-liquid mixture L that has become a high-speed swirling flow flows from the outlet 31 into the outlet passage 61, and in the outlet passage 61, the outlet pipe 61 turns around its circumference around the circulation pipe 65. It flows downstream. However, not all of the gas-liquid mixture L flows from the upstream to the downstream of the outlet channel 61, but the outer gas-liquid mixture L flows into the branch channel 62 by centrifugal force due to the swirl.

  The gas-liquid mixture L flowing through the branch channel 62 has the highest flow velocity in the vicinity of the inlet 62a, and bubbles expand due to the reduced pressure. And when flowing through the branch channel 62, the bubbles collapse and contract by being sheared, and a large amount of fine bubbles are generated at this time. In particular, since the cross-sectional area of the branch channel 62 gradually increases from the inlet 62a to the outlet 62b, the collapse and contraction of the bubbles are promoted.

  Subsequently, the gas-liquid mixture L flowing out from the outlet 62 b of the branch channel 62 is subdivided by the bubble cutting panel 64, passes through the discharge channel 63, and is ejected from the discharge port 71.

  On the other hand, the gas-liquid mixture L that has reached the most downstream side of the outlet channel 61 without flowing into the branch channel 62 flows into the circulation channel 66 in the circulation pipe 65 from the inlet hole 66 a, and in the outlet channel 61. It flows in the opposite direction to the flow of and flows out from the outlet hole 66b to the outlet channel 61. Thus, the circulation channel 66 of the circulation pipe 65 circulates a part of the gas-liquid mixture L in the outlet channel 61 from downstream to upstream. Of the gas-liquid mixture L swirling around the circulation pipe 65 in the outlet channel 61, the gas-liquid mixture L located inside reaches the most downstream portion of the outlet channel 61. Thus, it can be said that the gas-liquid mixture L swirling inside has a high gas mixing ratio, and even if it passes through the branch flow path 62, it is difficult to generate fine bubbles. According to the fine bubble generating nozzle 1 of the present invention, such a gas-liquid mixture L is repeatedly circulated to the upstream side, thereby allowing the gas and liquid mixing ratio to be appropriate and passing through the branch channel 62. The generation ratio of bubbles can be increased.

  Here, FIG. 5 is a diagram showing the internal pressure of each flow path in the fine bubble generating nozzle 1 of the present invention in shades, in which portions where the internal pressure is high are shown in dark color, and locations where the internal pressure is low are shown in light color. It appears. As shown in FIG. 5, the internal pressure of each flow path is highest in the introduction chamber 20, and then decreases in the order from the upstream to the downstream of the swirl chamber 30, and then the outlet flow path 61, the branch flow path 62, and the circulation flow path. 66 is low. In particular, since the internal pressure of the entire circulation channel 66 is the lowest, the gas-liquid mixture L that has reached the most downstream portion of the outlet channel 61 is sucked into the circulation channel 66 by a negative pressure. Further, since the internal pressure in the vicinity of the inlet 62 a of the branch channel 62 is as low as the internal pressure of the circulation channel 66, the gas-liquid mixture L in the vicinity of the outlet 31 flows into the outlet hole 66 b of the circulation channel 66. The flow toward the inlet hole 66a is not formed.

  The specific configuration of each part of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Fine bubble generating nozzle 10 Nozzle main body 20 Introducing chamber 21 Introducing port 30 Revolving chamber 31 Deriving port 40 Core 45 Revolving channel 50 Shearing chamber 60 Shearing member 61 Deriving channel 62 Branching channel 63 Discharging channel 64 Bubble cutting panel 65 Circulation pipe 66 Circulation channel 66a Inlet hole 66b Outlet hole 70 Lid 71 Discharge port

Claims (6)

An introduction chamber for introducing a gas-liquid mixture;
A swirl chamber that swirls the gas-liquid mixture flowing out of the introduction chamber;
A lead-out flow path for leading the swirled gas-liquid mixture;
A branch channel that branches off from the outlet channel;
A circulation channel that circulates the gas-liquid mixture that has reached the downstream of the outlet channel without flowing into the branch channel upstream of the outlet channel;
A fine bubble generating nozzle comprising:   The circulation channel is an inner hole of a cylindrical member, and this cylindrical member is inserted into the outlet channel, and the outer surface of the downstream end of the cylindrical member has an outlet channel and a cylindrical member. An inlet hole that communicates with the inner hole and introduces the gas-liquid mixture that has reached the downstream of the outlet channel into the inner hole of the cylindrical member is formed, and the outer peripheral surface of the upstream end of the cylindrical member is An outlet hole that communicates the outlet channel and the inner hole of the cylindrical member and leads the gas-liquid mixture that flows backward through the inner hole of the cylindrical member upstream of the outlet channel is formed. Item 2. A fine bubble generating nozzle according to Item 1.   3. The fine bubble generating nozzle according to claim 1, wherein the branch flow path is formed so that an opening area of an outlet is wider than an opening area of the inlet. 4.   4. The fine bubble generating nozzle according to claim 1, wherein one side surface of the branch flow path is a curved surface, and a side surface opposite to the curved surface is a flat surface. 5.   5. The generation of fine bubbles according to claim 1, wherein a core is disposed inside the swirl chamber, and a swirl flow path formed on a surface of the swirl swirls the gas-liquid mixture. nozzle. The fine bubble generating nozzle according to claim 5, wherein an inner surface of the swirl passage is formed in a step shape.