JP2012050929A - Defoaming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a defoaming device which can give strong turning flow to a fluid, can reduce the speed attenuation of the turning flow, and can efficiently perform the defoaming in a liquid.SOLUTION: An inner cylinder 3 is formed inside an outer cylinder 1 extending up and down, a lid 5 is formed so as to close an annular space 7 between the outer cylinder and the inner cylinder, an inlet pipe 9 of a fluid is eccentrically formed to the upper end outer periphery of the outer cylinder, an outlet pipe 11 which derives a fluid along the flow of a fluid spirally flowing the annular space turning to the downward from the upside is eccentrically formed to the lower end outer periphery of the outer cylinder, two or more circular or slit-like foam removing holes 13 are formed in the peripheral wall of the inner cylinder, the fluid flowing in the annular space is separated into a liquid and a gas by a centrifugal force, and the gas is caught in the inner cylinder 3 through the foam removing holes 13 and is discharged from the upper part of the inner cylinder 3.

Description

  The present invention relates to a defoamer that separates and discharges a gas mixed in a liquid.

In the case of beverages such as milk and juice, when oxygen is mixed in the beverage, the beverage is oxidized, so that oxygen is removed from the beverage.
Alternatively, when the flow rate of the liquid is measured, if a gas such as air is mixed, the flow rate of the liquid cannot be measured with high accuracy. Therefore, the flow rate measurement is performed after removing the gas from the liquid.
Further, in the turbidity measurement, since the mixed bubbles scatter and absorb light, there is a problem that cannot be distinguished from the mixed fine particles and causes an error, and it is indispensable to remove the bubbles.

Alternatively, if painting is performed with a gas such as air in the paint, pinholes are formed in the paint surface due to gas expansion during the infrared drying process of the paint, and the finished state of the paint is reduced. It is necessary to remove the gas from
Moreover, in the cleaning apparatus using ultrasonic waves, there is a problem that bubbles absorb the ultrasonic energy and the cleaning effect is lowered.
From such a background, removal of bubbles in the liquid is an important issue. As one method for removing gas from these liquids, conventionally, a swirling flow is applied to the fluid, and the liquid and the gas are separated by centrifugal force. A defoamer that captures gas in a cylinder and discharges the gas to the outside through the cylinder has been proposed (see, for example, Patent Document 1).

JP 2002-28634

However, the conventional configuration has a drawback that a strong swirling flow cannot be imparted to the fluid, and particularly when the fluid has a high viscosity, the velocity attenuation of the swirling flow cannot be reduced and the defoaming cannot be performed efficiently.
Accordingly, an object of the present invention is to eliminate the problems of the conventional techniques described above, to impart a strong swirling flow to the fluid, and to reduce the velocity attenuation of the swirling flow even for a fluid having a high viscosity. An object of the present invention is to provide a defoamer capable of efficiently defoaming a liquid.

In the present invention, an inner cylinder is provided inside an outer cylinder extending vertically, a lid is provided so as to close an annular space between the outer cylinder and the inner cylinder, and a fluid inlet pipe is eccentrically provided on the outer periphery of the upper end of the outer cylinder. In addition, an outlet pipe for deriving the fluid along the flow of the fluid flowing in a spiral shape from the top to the bottom of the annular space is provided eccentrically on the outer periphery of the lower end of the outer cylinder, and a circular or slit-like shape is provided on the peripheral wall of the inner cylinder. A plurality of bubble removal holes are provided, the fluid flowing in the annular space is separated into liquid and gas by centrifugal force, and the gas is captured in the inner cylinder through the bubble removal holes and discharged from the upper part of the inner cylinder. And
In the present invention, the fluid is introduced into the annular space from the eccentric inlet pipe, and flows in a spiral shape from the top to the bottom in the annular space, and the streamlines in the same rotational direction are formed along the spiral flow of the fluid. Since it is derived from the eccentric outlet pipe to be given, a strong swirling flow can be imparted to the fluid due to the synergistic effect of the inlet pipe and the outlet pipe, the velocity attenuation of the swirling flow can be reduced, and the gas in the liquid can be efficiently removed.

In this case, the inner ends of the inlet pipe and the outlet pipe may extend to the center of the outer cylinder.
The inlet pipe and the outlet pipe may be arranged in a bar shape in a top view.
A detachable jet that provides an appropriate inflow velocity may be provided inside the inlet pipe.
The bubble removal hole of the inner cylinder may be provided in the central portion of the inlet pipe, the upper and lower ends of the inner cylinder, and other intermediate portions at an angle of 90 to 120 ° with respect to the rotational flow rotation direction.
The surface roughness of the inner wall of the outer cylinder or the outer wall of the inner cylinder may be Rmax ≦ 6.3S {JIS finishing symbol ▽▽▽ or more}.
A guide that has a plurality of passages inside the outer cylinder and converges conically from the inner diameter of the outer cylinder to an inner diameter of “√ {(square of inner cylinder outer diameter) + (square of inner diameter of inlet tube)}” or more. It may be provided.
The outer cylinder may be bundled between the inlet pipe and the outlet pipe from the inner diameter of the outer cylinder to an inner diameter corresponding to “√ {(square of inner cylinder outer diameter) + (square of inlet pipe inner diameter)}”.

  In the present invention, the fluid is introduced into the annular space from the eccentric inlet tube, flows spirally from top to bottom in the annular space, and is led out of the eccentric outlet tube along the spiral flow of the fluid. Therefore, a strong swirling flow can be imparted to the fluid by the two vortex generation effects of the inlet tube and the outlet tube, the velocity attenuation of the swirling flow can be reduced, and the gas in the liquid can be efficiently removed.

It is sectional drawing which shows one Embodiment of the deaerator by this invention. It is II-II sectional drawing of FIG. A is a cross-sectional view of the inlet pipe portion, and B is a cross-sectional view of the outlet pipe portion. It is sectional drawing which shows a bubble removal hole, and shows the angle of (theta) = 90 degree | times. A and B are sectional views of the jet, and C and D are end views. A cross-sectional view of the jet is shown. It is a figure which shows another form of FIG. It is a figure which shows the other form which attached the guide. It is a figure which shows another form which attached the constriction.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes an outer cylinder {= container} having an inner diameter Dh extending vertically, and an inner cylinder 3 {= bubble discharge pipe} having an outer diameter Db also extending vertically is concentric inside the outer cylinder 1. Is arranged. Lids 5 (5A, 5B) are respectively provided at the upper end and the lower end of the outer cylinder 1 and the inner cylinder 3, and the lids 5A, 5B are formed between the outer cylinder 1 and the inner cylinder 3. The annular space 7 is arranged so as to be closed.

An inlet pipe 9 having an inner diameter d is provided on the outer periphery of the upper end of the outer cylinder 1, and an outlet pipe 11 having an inner diameter d is provided on the outer periphery of the lower end of the outer cylinder 1. The inner diameter of the inner cylinder 3 described above is preferably equal to or larger than the inner diameter d of the inlet pipe 9 and the outlet pipe 11. As shown in FIGS. 2 and 3, the inlet tube 9 and the outlet tube 11 are each eccentric from the central portion M of the outer cylinder 1 and are arranged in parallel with the inscribed circle tangent line of the outer cylinder 1, respectively. They are arranged in a row of bars as if they were continuous. The inlet pipe 9 is provided at the outer periphery of the upper end of the outer cylinder 1, but is not limited thereto. For example, when the height of the outer cylinder 1 is H, it may be provided at a height within H / 2 from the top of the head. Good.
The projecting end surface of the inlet tube 9 to the outer cylinder 1 is arranged at right angles to the diameter position of the inner wall of the outer cylinder 1 and the outer wall of the inner cylinder 3, and has a donut shape (annular space) constituted by the inner wall of the outer cylinder 1 and the outer wall of the inner cylinder 3 As a flow path, the fluid ejected from the inlet pipe 9 forms a swirl flow (vortex flow).
Here, when viewed from the upper end of the outer cylinder 1, the outlet pipe 11 is arranged in series with the inlet pipe 9 (in a single-row bar shape), and further, in a space sandwiched between the inner wall of the outer cylinder 1 and the outer wall of the inner cylinder 3, Since the end face is arranged, a vortex is generated in the outlet pipe 11 regardless of the inlet pipe 9 generating swirl flow, and the rotation direction of the swirl flow is the same. That is, since the generated swirl flow in the outlet pipe 11 helps the attenuation of the generated swirling flow in the inlet pipe 9, the bubble removal efficiency is improved.

In the above configuration, as shown in FIG. 4, a detachable jet 10 that provides an appropriate inflow velocity inside the inlet pipe 9 may be provided. The shape of the jet 10 is preferably a “semi-circular structure” formed by the inner wall of the inlet pipe 9 as shown in FIGS. 5B and 5D in order to bring fluid into close contact with the inner wall of the outer cylinder 1. As shown in 5C, it may be a coaxial circular structure. In the case of a coaxial coaxial structure, the jet inner diameter dj is expressed as “ΔP = 0.1 (from the relational expression“ Q = 0.5 dj ² × √ (ΔP / 10) ”when the applied fluid viscosity is equivalent to water. “Jet inner diameter dj” giving “Q (l / min)” at the time of pressure loss of “MPa” is determined.
When the inner diameter d of the inlet tube 9 is sufficiently larger than “dj”, as shown in FIG. 6, a stopper 10A having a jet having an inner diameter close to d is fixed to the inner wall, and the replaceable jet “dj” Is inserted. In order to increase the bubble removal efficiency η, the smaller the “dj”, the better. However, on the other hand, it is necessary to increase the required pumping capacity of a pump (not shown). However, when the pump is already configured, it is necessary to determine the optimum “jet 10 inner diameter dj” based on the pumping ability of the pump. However, since the optimum “dj” varies depending on the viscosity of the applied fluid, the “vortex generating jet 10” is exchanged in the actual operating state and finally determined.

As the applied fluid viscosity increases, the attenuation of the swirling flow generated by the jet 10 provided in the inlet pipe 9 increases. In order to suppress this, the surface roughness of the inner wall of the outer cylinder 1 is set to Rmax ≦ 6.3S {JIS finishing symbol ▽▽▽ or more} to reduce the resistance caused by the inner wall and maintain the generated eddy current. In order to improve the bubble removal efficiency.
The bubble removal efficiency η improves as the swirl flow strength increases. However, the bubble removal efficiency η and the necessary pressure loss ΔP have a relationship of “η∝√ΔP”, and the pressure loss ΔP in the defoamer increases with the square of η. Moreover, ΔP is also greatly influenced by the viscosity of the applied fluid, and in the case of the fixed jet 10, there is a case where the required flow rate may not be obtained due to the limitation due to the capability of a pump (not shown) equipped in the system.
In this configuration, the end face portion of the inlet pipe 9 inserted into the outer cylinder 1 so that an appropriate inner diameter of the jet 10 can be selected in the field to obtain the maximum bubble removal effect with respect to the equipped pump (not shown). Thus, the jet 10 can be replaced. As a result, an optimum jet configuration was made possible with respect to the existing pump capacity.

The inner end 9A of the inlet pipe 9 extends to the center M of the outer cylinder 1 as shown in FIG. 3A. Therefore, a jet vortex A that flows spirally is generated at the outlet of the inner end 9 </ b> A of the inlet pipe 9, and the jet vortex A flows into the annular space 7. The fluid that has flowed into the annular space 7 flows spirally from the top to the bottom within the annular space 7. The annular space 7 is filled with fluid. Moreover, 11 A of inner ends of the exit pipe | tube 11 are extended to the center part M of the outer cylinder 1, as shown to FIG. 3B. Accordingly, a suction vortex B that flows in a spiral shape is generated at the inlet of the inner end 11A of the outlet pipe 11, and this suction vortex B remains as the vortex B in the outer peripheral portion of the lower end of the outer cylinder 1. The direction does not change, the vortex B is not opposed, and the vortex B flows into the inner end 11 </ b> A of the outlet pipe 11.
Even when the generated vortex generated by the inlet pipe 9 does not exist, the vortex accompanying the outflow to the outlet pipe 11 is generated, and the rotational direction of the swirl flow is the same as that of the inlet pipe generated vortex. The flow is maintained, which contributes to the improvement of bubble removal efficiency.

  As shown in FIG. 1, a plurality of circular bubble removal holes 13 are provided on the peripheral wall of the inner cylinder 3 at substantially equal intervals in the vertical direction (longitudinal direction). The bubble removal hole 13 is not limited to a circle, and may be, for example, a long slit-like hole. A vent hole 21 is provided at the upper end of the inner cylinder 3, and the vent hole 21 is closed with a vent plug (not shown). Further, a communication hole for discharging deposits such as fine particles in the fluid is provided in the peripheral wall at the lower end of the inner cylinder 3, and a drain (discharge) hole 23 is provided in the center of the inner cylinder bottom portion. 23 is closed by a stopper (not shown).

When the fluid flows spirally in the annular space 7, centrifugal force is applied to the fluid, a heavy liquid is drawn outward in the annular space 7, and a light gas stays inward to promote separation. To do. The gas staying inward enters the inside of the inner cylinder 3 through the bubble removal hole 13, rises in the inner cylinder 3 by buoyancy, and is discharged through the vent hole 3A.
The bubble removal holes 13 are provided in a vertical line at intervals of 90 ° with respect to the circumferential direction of the inner cylinder 3. The bubble removal holes 13 are provided at both the position of the lid 5A passing at the upper end of the inner cylinder 3 and the position of the lid 5B passing at the lower end of the inner cylinder 3.
The bubble removal hole 13 is also provided at a position P where the inner end 9A of the inlet pipe 9 extends. The strongest swirl flow A is given to the position P (the inner end 9A of the inlet pipe 9), the separation of the liquid and the gas is strongly promoted, and the most gas is sucked into the bubble removal hole 13 at the position P. The position of the bubble removing hole 13 provided in the inner cylinder 3 is preferably a portion that coincides with the central axis of the inlet pipe 9 where the whirling flow is strongest and the centrifugal force effect is great.

As shown in FIG. 7, the bubble removal hole 13 is preferably formed so as to face the flow direction of the swirl flow A, and is opened to a position where the pressure behind the flow becomes low.
The important elements in the defoamer of this configuration are (I) forming a strong swirling flow, (II) suppressing and maintaining the deceleration of the swirling flow, and (III) reducing the swirling flow radius to effect the centrifugal effect. To make it stronger. When the direction of the bubble removal hole 13 provided in the peripheral wall of the inner cylinder 3 is directed to the swirl flow direction A, for example, when θ <90 ° in the configuration of FIG. Inflow and increase the attenuation of swirl flow velocity. For this reason, in the configuration example of FIG. 7, the direction θ of the bubble removal hole 13 is set to, for example, 120 ° with respect to the swirling flow, and the swirling flow does not directly flow into the inner cylinder 3. The direction θ of the bubble removal hole 13 may be “θ ≧ 90 °”. With this configuration, the swirling flow does not flow directly into the inner cylinder 3.

In these configurations, as shown in FIG. 3, by extending the inner end of the inlet pipe 9 to the center of the outer cylinder 1, there is less collision / diffusion with the fluid inside the outer cylinder 1, and the outer cylinder 1. A jet vortex A (circular flow) formed by the inner wall is generated and can be smoothly introduced into the annular space 7.
Further, by extending the inner end of the outlet pipe 11 to the center portion of the outer cylinder 1, an appropriate suction vortex (discharge vortex) B (rotation) is established in the flow path space formed by the outer cylinder 1 and the inner cylinder 3. The flow vortex B is generated, and the direction of the vortex B is not changed, the vortex B is not opposed, and flows into the inner end along the vortex B. That is, since the “suction vortex (discharge vortex) B (rotation flow)” assists the attenuation of the “spout vortex A (rotation flow)”, the space formed by the outer cylinder 1 and the inner cylinder 3 Application of a strong swirling flow to the fluid and a decrease in velocity attenuation of the swirling flow can be reduced, and the gas in the liquid can be efficiently removed.

The swirl flow (vortex flow) generated by the jet flow from the inlet pipe 9 flows toward the outlet pipe 11 at the lower part of the cylindrical container while the bubbles are separated in the liquid by the centrifugal force effect.
At this time, as shown in FIG. 8, a conical structure (guide) 12 may be provided at an intermediate position between the inlet pipe 9 and the outlet pipe 11 so as to be inscribed in the outer cylinder 1.
The structure 12 is a conical annular member that converges from the inner diameter of the outer cylinder 1 to the inner diameter of the dc 2 toward the outlet in a conical shape, the flow path becomes smaller in a conical shape, and the inclination is θ. The radius is reduced to increase the centrifugal force effect and reduce the velocity attenuation of the fluid. Assuming that the outer diameter of the bubble removing pipe (inner cylinder 3) is db, the inner diameter d of the inlet pipe 9 (outlet pipe) and the outlet diameter dc2 of the conical guide are designed in a relationship of “(dc2 ² −db ² ) ≦ d ² ”. A part of the liquid is pushed into the bubble removing tube (inner tube 3) together with the bubbles collected on the outer peripheral portion of the inner tube 3 and contributes to bubble discharge. In the upper part of the conical guide 12, a plurality of passages 12A having a diameter of dc are provided in order to discharge bubbles accumulated in the outer wall of the cylinder and the inner wall of the outer cylinder 1.
On the other hand, at the bottom of the cylindrical container 1, foreign matters such as fine particles mixed in the liquid accumulate due to the centrifugal effect of the swirling flow. When enhancing such a fine particle separation function, the outlet pipe 11 is arranged at a high position from the bottom surface of the outer cylinder 1. On the other hand, when separation of fine particles is disliked, the outlet pipe 11 may be provided so as to coincide with the bottom of the outer cylinder 1.

Instead of the guide 12, the inner and outer walls of the outer cylinder 1, as shown in FIG. Thus, the speed (strength) of the swirling flow may be improved.
As a result of the inner diameter of the outer cylinder 1 being reduced from dh to ds, the swirl flow radius is reduced, the centrifugal force effect is increased, and the bubble separation effect is enhanced. ds is designed in relation to the inner diameter d of the inlet / outlet pipe and “(ds ² −db ² ) ≦ d ² ”. When the outlet pipe 11 is viewed from the upper part of the outer cylinder 1 in the axial direction so as to generate the same swirling flow as that of the swirling flow (vortex flow) generated in the inlet pipe 9, At the coincident position, it is inscribed in the outer cylinder 1, and the inner tip of the outer cylinder 1 is opened in a region constituted by the outer cylinder 1 and the inner cylinder (bubble discharge pipe) 3. As a result, since a donut-like (annular) space constituted by the outer cylinder 1 and the inner cylinder (bubble discharge pipe) 3 flows out to the outlet pipe 11 as a flow path, a swirl flow (vortex flow) is inevitably generated, In addition, since the rotational direction of the swirl flow is the same as the rotation direction of the swirl flow generated in the inlet tube 9, the swirl flow (vortex flow) is strengthened, and the swirl flow drop due to velocity attenuation is suppressed.

  When the flow velocity of the swirl flow (vortex flow) is low, it is a laminar flow state. For example, reference: Yasuji Shibata / Masayuki Kakuno, “Fundamentals of Fluid Mechanics and Fluid Machinery” As shown in FIG. 70, the velocity attenuation of the vortex is not affected by the roughness of the tube wall, and generally has a relationship of “tube friction coefficient λ = 64 / Re” (Moody diagram). However, when a strong vortex flow is generated in the outer cylinder 1 as in this configuration, because of the turbulent state, the “tube friction coefficient λ” is greatly affected by the surface roughness of the inner wall, and the velocity damping is greatly increased. Let In order to suppress this influence, in this configuration, by polishing the inner wall of the outer cylinder 1 (further, the outer wall of the inner cylinder 3 having the bubble removal holes 13), the surface roughness is reduced to Rmax ≦ 6.3S. As {JIS finishing symbol ▽▽▽ or more}, the generated vortex is maintained to improve the bubble removal efficiency. When a strong swirl flow is generated in the annular space 7 in this way, a fluid having a large specific weight is separated by centrifugal force on the outer peripheral portion, and the pressure increases, while the pressure in the inner cylinder 1 region decreases. A gas with a low specific weight is separated.

The bubble removal efficiency η has a relationship of “η∝V” that is linearly proportional to the swirling flow velocity V, and has a relationship of “η∝√ΔP” to the pressure difference ΔP that generates V. The speed of the swirling flow (vortex flow) generated first is uniquely determined by the pressure difference ΔP applied to the jet 10 as “V∝√ΔP”. It is how to sustain without attenuation.
The velocity attenuation of the swirl flow increases as the viscosity of the fluid increases. In addition, the surface roughness of the flow path, changes in the flow path, and the like are greatly affected.
Therefore, in this configuration, as described above, the surface roughness of the outer wall of the inner cylinder 3 is set to Rmax ≦ 6.3S {JIS finishing symbol ▽▽▽ or more}, and the generated vortex flow strength is maintained, At the same time as improving the removal efficiency η, the direction θ of the bubble removal hole 13 on the peripheral wall of the inner cylinder 3 is set to “θ ≧ 90 °” with respect to the swirling flow A, so that the swirling flow does not flow directly into the inner cylinder 3. It is said. Further, the change in the flow direction has a structure in which the direction of rotation of the inlet tube 9 and the direction of rotation of the generated vortex of the outlet tube 11 coincide with each other in order to promote velocity attenuation.
When the swirl radius r is decreased, the centrifugal force F effect is increased as apparent from the relational expression “F = MV ² / r”, and the bubble separation effect is increased. M is the mass of the rotating fluid. In the central part of the inlet pipe 9 and the outlet pipe 11, as shown in FIG. 9, the inner and outer diameters of the outer cylinder 1 can be reduced to form a constricted structure. That is, in the structure of FIG. 9, the rotating flow (vortex flow) radius decreases toward the outlet side, so that the centrifugal force effect becomes large and the bubble separation effect is improved even at the same flow rate.

The inside of the bubble removal cylinder (inner cylinder 3) communicating with the upper and lower sides of the cylindrical container (outer cylinder 1) is the rotational direction of the rotational flow of a plurality of circular or slit-shaped bubble removal holes 13 provided on the peripheral wall of the inner cylinder 3 Since the angle with respect to is 90 degrees to 180 degrees, the flow velocity is almost zero, without being affected by the swirling flow (vortex flow). For this reason, the bubble floats to the upper part of the container by the action of the buoyancy of the bubble with respect to the liquid inside the bubble removal cylinder 3 and moves toward the bubble discharge hole 21.
However, when the inner diameter of the bubble removing cylinder 3 is small, especially when the fluid viscosity is high, the bubble rising speed is small. Therefore, the inner diameter db of the bubble removing cylinder 3 is related to the inner diameter d of the inlet tube 9. , “Db ≧ d” is set to raise the bubbles.

In order to effectively raise and discharge bubbles, the opening of a “flow rate adjusting valve (not shown)” provided in the bubble discharge hole 21 is increased so that the liquid flow rate is increased. Let it flow out to the wall and gently reflux to the top of the liquid. When it is desired to suppress the liquid recirculation amount {= not to recirculate}, the “flow rate adjusting valve” is tightly squeezed to discharge only bubbles.
For example, 25 (° C.) in the relative viscosity of the "water"^{"0.89 × 10 -3 (Pa · s} ) ", "air" coefficient of viscosity "0.0182 × 10 ^-3 (Pa · of s) ”, the viscosity coefficient of the gas is as small as about 1/50. Therefore, even if the gas is tightly squeezed {= the inner diameter of the flow rate adjusting valve is small}, there is a feature that is not influenced by the discharge of bubbles. However, the floating effect of the bubbles collected in the bubble discharge pipe {= the effect of flowing out together with the flow of the reflux liquid} is reduced. For this reason, when it is desired to effectively discharge the bubbles, it is important to increase the reflux amount.
A communication hole 23 for discharging the fluid in the bottom space constituted by the outer cylinder 1 and the inner cylinder 3 (bubble discharge pipe) is provided at the lowermost end of the inner cylinder 3. A drain channel 23A is provided at the center of the bottom of the inner cylinder 3 (bubble discharge pipe).

In the present embodiment, the fluid is introduced into the annular space 7 from the eccentric inlet tube 9, flows in a spiral shape from the top to the bottom in the annular space 7, and is further eccentric along the spiral flow B of the fluid. In the annular (doughnut-shaped) space 7 which is led out from the outlet pipe 11 and is constituted by the outer cylinder 1 and the inner cylinder 3 and has a width corresponding to the inlet pipe 9, a swirling flow (vortex) is generated, and the outlet pipe 11 is also arranged in a structure that generates a swirling flow in the same rotational direction, so that a strong swirling flow can be imparted to the fluid due to the synergistic effect of both, and only when a swirling flow is formed at the inlet pipe 9, The velocity attenuation of the swirling flow can be reduced, and the gas can be removed efficiently.
Moreover, the surface roughness of the inner wall of the outer cylinder 1 and the outer wall of the inner cylinder 3 formed as a swirl flow is set to Rmax ≦ 6.3S {JIS finishing symbol ▽▽▽ or more}, or a bubble flow opened in the inner cylinder 3 By defining the angle of the path (hole 13) so as not to oppose the whirling flow, the generated vortex strength is maintained and the velocity attenuation is suppressed.
However, a phenomenon in which the rate of rate decay increases as the applied fluid viscosity increases cannot be avoided. For this reason, the centrifugal force F has a relationship between the rotational flow velocity V, the mass M, and the rotational radius r at “F = MV ² / r”. The conical guide 12 that gradually converges in the downstream direction for reducing the flow radius is provided inside the outer cylinder 1 or the inner and outer diameters of the outer cylinder 1 are reduced to form a constricted annular flow path. High bubble removal efficiency may be obtained by suppressing a decrease in bubble removal efficiency due to attenuation.
As mentioned above, although this invention was demonstrated based on one Embodiment, it is clear that this invention is not limited to this.

DESCRIPTION OF SYMBOLS 1 Outer cylinder 3 Inner cylinder 5 (5A, 5B) Lid body 7 Annular space 9 Inlet pipe 11 Outlet pipe 13 Bubble removal hole

Claims (8)

An inner cylinder is provided inside the outer cylinder extending vertically,
A lid is provided so as to close the annular space between the outer cylinder and the inner cylinder,
An eccentric inlet pipe for the fluid is provided on the outer periphery of the upper end of the outer cylinder,
An outlet pipe for deriving the fluid along the flow of the fluid flowing spirally from the top to the bottom of the annular space is provided eccentrically on the lower end outer peripheral portion of the outer cylinder,
A plurality of circular or slit-shaped bubble removal holes are provided on the peripheral wall of the inner cylinder,
A defoamer characterized in that the fluid flowing through the annular space is separated into liquid and gas by centrifugal force, and the gas is captured in the inner cylinder through the bubble removal hole and discharged from the upper part of the inner cylinder.   2. The defoamer according to claim 1, wherein each inner end of the inlet pipe and the outlet pipe extends to a center portion of the outer cylinder.   The defoamer according to claim 1 or 2, wherein the inlet pipe and the outlet pipe are arranged in a row of bars in a top view.   The defoamer according to any one of claims 1 to 3, wherein a detachable jet that provides an appropriate inflow velocity is provided inside the inlet pipe.   The bubble removal hole of the inner cylinder is provided at a central portion of the inlet pipe, an upper end and a lower end of the inner cylinder, and other intermediate portions at an angle of 90 to 120 ° with respect to the rotational flow rotation direction. Item 5. A defoamer according to any one of Items 1 to 4.   The defoamer according to any one of claims 1 to 5, wherein a surface roughness of the inner wall of the outer cylinder or the outer wall of the inner cylinder is set to Rmax ≦ 6.3S {JIS finishing symbol ▽▽▽ or more}. .   A guide that has a plurality of passages inside the outer cylinder and converges conically from the inner diameter of the outer cylinder to an inner diameter of “√ {(square of inner cylinder outer diameter) + (square of inner diameter of inlet tube)}” or more. The defoamer according to claim 1, wherein the defoamer is provided.   The outer cylinder is confined between the inlet pipe and the outlet pipe from the inner diameter of the outer cylinder to an inner diameter corresponding to “√ {(square of inner cylinder outer diameter) + (square of inlet pipe inner diameter)}”. The defoamer according to any one of claims 1 to 6.

Images