WO2019239833A1

WO2019239833A1 - Fluid-mixing apparatus and emulsion preparation method

Info

Publication number: WO2019239833A1
Application number: PCT/JP2019/020385
Authority: WO
Inventors: 奥田　伸二
Original assignee: 株式会社Ｏｋｕｔｅｃ
Priority date: 2018-06-12
Filing date: 2019-05-23
Publication date: 2019-12-19
Also published as: JP6557871B1; JP2019214012A

Abstract

The present invention addresses the problem of providing a method for providing a homogeneous, stable emulsion from a mixed liquid comprising an aqueous liquid and a hydrophobic liquid that is incompatible with aqueous liquids without using a surfactant, by using a recirculating batch mode gas-liquid shearing fluid mixing apparatus provided at least with a mixing chamber, a pump, a fine bubble-supplying unit, and a gas intake pipe, so as to introduce air from the downstream side of a gas-liquid shearing vortex pump.

Description

Fluid mixing apparatus and emulsion preparation method

The present invention relates to a gas-liquid shearing type fluid mixing apparatus for mixing a plurality of liquids (dispersoid and dispersion medium), and a method for preparing an emulsion composed of a plurality of liquids. In detail, the present invention can be refined and homogenized at low cost to a submicron level by generating fine bubbles in a mixture of a plurality of liquids and generating a shear force between the plurality of liquids. A simple pump-circulating fluid mixing device capable of producing a stable emulsion, and a method for preparing a homogeneous and highly stable emulsion using such a fluid mixing device without using a surfactant About.

Emulsions are used in foods and beverages such as butter, mayonnaise, milk and ice cream, creams used in pharmaceuticals and cosmetics, inks and paints such as acrylic paint, adhesives, photosensitive layers for photographic films, and sealants for asphalt pavements. It is used in a wide variety of fields, from natural materials to construction materials.

A state in which one of a plurality of liquids that are not originally mixed, such as water and oil, becomes fine particles and dispersed in the other is called emulsification, and the emulsified liquid is called an emulsion. Such emulsions are roughly classified into two. For example, familiar oils such as milk and mayonnaise are oil / water emulsions such as butter and margarine. An emulsion having water droplets dispersed therein is called a W / O (Water in Oil) type emulsion.

Emulsification occurs when physical energy such as impact force, shear force, or cavitation force is applied to a plurality of liquids that are not originally mixed, but generally the emulsion is in an extremely unstable state, and if left untreated, it gradually separates into two layers. End up. Therefore, an emulsifier is added to stabilize the emulsion. By adding an emulsifier (for example, surfactant), it becomes possible to disperse water and oil which are contradictory, and the obtained emulsion is stabilized.

Conventionally, when an oily substance having a specific function is emulsified and dispersed in water, an emulsifier having a required HLB (Hydrophilic-Lipophilic Balance) value is selected according to the properties of the oily substance, and emulsified and dispersed. . The required HLB value of the surfactant used as the emulsifier needs to be properly used for each of the case of making the O / W type emulsion and the case of making the W / O type emulsion. Therefore, the determination of an appropriate surfactant combination is very cumbersome and requires great effort. In addition, when many kinds of oily substances are mixed, it is almost impossible to stably emulsify. In addition, the surfactant is not necessary for the original purpose of the solution, may inhibit the function of the solution, and can be an irritant to the skin when used in cosmetics. Furthermore, since the surfactant has low biodegradability and causes foaming, it is a serious problem such as environmental pollution.

Therefore, an emulsification (or emulsification) technique without adding an emulsifier has been developed.
For example, Patent Document 1 discloses a fluid mixer that mixes a plurality of types of fluids, and it has been confirmed that this fluid mixer has an ability to produce an emulsion having a particle size of about 10 μm or less.
In Patent Document 2, uniform dispersion, dissolution, solubilization, and emulsification of a gas in a liquid and uniform dispersion, dissolution, solubilization, and emulsification of a liquid in a different liquid can be performed in a large volume and in a short time. A processing apparatus that can be used has been disclosed, and it has been confirmed that an emulsion fuel of light oil and water in which the milky white state is maintained for about half a day can be obtained.
Patent Document 3 discloses a technique for producing an emulsion fuel in which water particles are uniformly dispersed in a fuel oil component by a static mixer without the aid of a chemical action by a surfactant.
Patent Document 4 discloses a technique for providing an emulsion having excellent dispersion stability without using an emulsifier (surfactant), and is a water-in-oil type (W) containing hexadecane and water prepared by ultrasonic irradiation. / O) Dispersion stable by adding any one of salt, hydrogen bonding molecule, alcohols (eg sodium chloride, magnesium chloride, urea, formamide, ethanol, glycerin) to the emulsion as a surface inactive substance The effect of improving the properties has been confirmed.

JP 2014-004534 A Patent No. 5380545 specification JP 2009-203323 A JP2016-165716A

The technique of Patent Document 1 is a method of mixing by passing a mixed fluid once like a static mixer, and the obtained emulsion is not at a sufficient level in homogeneity, fineness, and high-concentration emulsification.
When the result of Example 5 of patent document 2 is seen, it turns out that the emulsification which does not put gas shows a better result. That is, in this technique, there is a problem that large bubbles enter the pump and lower the pump efficiency, and the effect of emulsification using gas cannot be achieved.
The emulsion fuel produced by the apparatus of Patent Document 3 has a dispersion time of about several tens of seconds and is not assumed to provide a long-time stable emulsion.
Although the technique of Patent Document 4 does not use an emulsifier (surfactant), it is necessary to add any one of a salt, a hydrogen bonding molecule, and an alcohol in order to improve the dispersion stability of the emulsion.

Accordingly, in order to solve the above problems, the present invention pays attention to a circulating batch type gas-liquid shearing type fluid mixing method, and can be emulsified and dispersed at low cost without using an additive such as a surfactant. The main object is to provide a mixing device and a homogeneous and stable emulsion.

The present invention generally includes a mixing unit that receives and mixes liquids, a pump unit that mixes and circulates liquids, a liquid transfer unit that transfers circulated liquids, and a gas suction unit that supplies gas from the outside. A gas-liquid shearing type liquid mixing apparatus is provided.

The lower part of the mixing unit is provided with a flow path for returning the circulating liquid to the inside of the mixing unit, and a bubble supply unit is provided in the middle of the flow path to introduce gas via the gas suction unit to generate bubbles.

Bubbles generated in the bubble supply unit are defined by the International Standards Organization (ISO) Fine Bubble Technical Committee (TC281), according to the diameter, in the form of millibubbles (1 mm or more), submillibubbles (less than 1 mm and 0.1 mm or more) , Microbubbles (less than 0.1 mm (100 μm) and above 1 μm) and ultrafine bubbles (less than 1 μm). Bubbles with a diameter of 100 μm or more are visible. In addition, microbubbles and ultrafine bubbles having a diameter of less than 100 μm are collectively referred to as fine bubbles, but the presence of microbubbles can be visually confirmed because water is white and cloudy, and ultrafine bubbles cannot be visually confirmed. The mode diameter of ultrafine bubbles has been confirmed to be 100 nm to 200 nm in diameter by various measurement methods (dynamic scattering method, laser diffraction method, particle tracking analysis method, electrical detection band method). .
In water, millibubbles and submillibules rise (approximately 5-6 m / min) and rupture and disappear at the surface of the water. Microbubbles are slowly rising (approximately 3 mm / min) and contract and disappear in water. However, ultrafine bubbles have a higher viscous drag from the liquid than buoyancy, so they perform Brownian motion in the liquid. However, it stays for a long time (several days to several weeks).

If gas is present in the fluid, the pump cannot be sucked and eventually causes a pump failure. Therefore, it is required to remove bubbles present in the mixing chamber of the mixing unit.
Since a rotating flow is generated in the liquid in the mixing chamber, the liquid is unevenly distributed on the outer periphery due to the centrifugal force, while the gas is collected at the center of the rotating flow. Also, bubbles with larger diameters rise faster. Therefore, by attaching a fluid discharge port to the lower part of the outer peripheral wall of the mixing chamber, the fluid from which most bubbles are removed can be taken out.
In the present invention, depending on the viscosity and type of the target dispersion medium and dispersoid, the inner diameter of the mixing chamber, the height from the attachment point of the discharge port to the upper surface of the fluid, the circumferential speed and the axial speed of the rotating flow By controlling the suction flow rate by the pump, millibubbles and submillibules with a diameter of 100 μm or more are removed, preferably, millibubbles and submillibules with a diameter of 100 μm or more and microbubbles with a diameter of 1 μm or more are removed, Only ultrafine bubbles with a diameter of less than 1 μm remain. This is because even if microbubbles and ultrafine bubbles remain in the fluid, the pump efficiency is not affected.

According to the present invention, although not limited, the fluid mixing device having the above-described configuration is composed of an aqueous liquid and a hydrophobic liquid that is incompatible with the aqueous liquid without using an emulsifier such as a surfactant. A stable O / W (Water in Water) type emulsion or W / O (Water in Oil) type emulsion at the submicron level (average diameter is several μm) can be obtained. The emulsion obtained by the present invention is stably present without separation for 3 days or more, preferably 7 days or more, more preferably 2 weeks or more, and even more preferably 1 month or more. Emulsion is sealed in a sealed bottle and allowed to stand at room temperature, and the occurrence of separation between the cloudy phase and the transparent phase and the complete phase separation between the aqueous liquid and the hydrophobic liquid are visually observed. Judgment by

In the present invention, the aqueous liquid constituting the emulsion is selected from the group consisting of water; and a mixture of an organic solvent compatible with water and water, but water is preferable in consideration of the load on the human body and the environment. In the present invention, the hydrophobic liquid constituting the emulsion is not limited as a natural oily substance having an insecticidal or insecticidal effect. For example, allspice oil, caypté oil, cinnamon oil, cedar oil, citronella oil, geranium oil , Soybean oil, thyme oil, clove oil, garlic oil, basil oil, peppermint oil, verbena oil, castor oil, peppermint oil, pine oil, lavender oil, lemongrass oil, lemon eucalyptus oil, rosemary oil, etc. . Other natural oils include linseed oil, olive oil, giraffe oil, sesame oil, rice bran oil, corn oil, rapeseed oil, palm oil, palm kernel oil, peanut oil, sunflower oil, hazelnut oil, safflower oil, cottonseed oil, coconut oil, etc. Can be mentioned.

In the emulsion of the present invention, a natural oil-derived substance having an insecticidal or insecticidal effect and other natural oily substances can be used in combination with a natural product-derived insecticidal or insecticidal substance. Pyrethroids extracted from larval chrysanthemum ovules that have an insecticidal or insecticidal effect on mosquitoes, cockroaches, mites, flies, etc .; Nicotine, a tobacco extract that has insecticidal effects; Sabaziric acid (Tiglic acid) extracted from lilyaceae plant Savage, which acts as a contact poison and digestive poison for insects; Insecticides such as ticks, fish killing From plants of the genus Roncocarpus and Deris (for example, Dokufuji), which are widely effective as agents and pesticides Rotenone issued; and prevents molting and emergence of insect larvae, thereby appetite, and the like neem oil extracted from neem (scientific name Azadirachta-Indeka (Azadirachta indica)).

Various additives can be added to the emulsion prepared according to the present invention as long as the stability of the emulsion is not adversely affected. The additive that can be used in the present invention is 1 selected from the group consisting of sodium, magnesium, phosphorus, chlorine, potassium, calcium, chromium, manganese, iron, cobalt, copper, zinc, selenium, molybdenum, iodine and the like A plurality of essential minerals; including one or more porous materials selected from the group consisting of activated carbon, silica gel, zeolite, silicon dioxide (mesoporous silica), aluminum oxide, and the like.

However, in the present invention, a surfactant having a function of reducing the interfacial tension at the interface between a so-called aqueous liquid (for example, water) and a hydrophobic liquid (for example, oil), and even when added to an emulsion, the interfacial tension is reduced. Among those having no action to be selected, it is selected from any one of salts, hydrogen-bonding molecules and alcohols (for example, selected from the group consisting of sodium chloride, magnesium chloride, urea, formamide, ethanol and glycerin). Do not use any additives.

In the present invention, examples of the gas introduced for gas-liquid shear include air, oxygen, ozone, nitrogen, argon, hydrogen, and the like, which can be selected as appropriate in view of the effectiveness of the insecticidal or insecticidal substance used. However, air is preferable from the viewpoint of simplicity.

Definitions of terms used in the present specification are shown below.
“Fluid” is a general term for a continuum in which no shear stress is generated in a stationary state. In general, it is a continuum that is not solid, and liquids, gases, and plasmas correspond to fluids as forms of substances.
“Emulsion” (or sometimes referred to as “emulsion”) refers to a dispersion solution in which both the dispersoid and the dispersion medium are liquid. Also called emulsion or emulsion. Making two separated liquids into an emulsion is called emulsification, and a substance having an emulsifying action is called an emulsifier. In the present invention, it is called an emulsion.
“Microemulsion” is a type of dispersion consisting of two liquids similar to emulsions, but with a diameter as small as about 100 nm or less, composed of micelles, thermodynamically stable, and requires strong stirring. It can be easily formed. Since the micelle is small, there is little scattering of visible light, and the feature is that it looks transparent or translucent.
A “dispersed system” is a substance in which particles having a size of about 1 nm to 1000 nm (1 μm) are suspended or suspended in a gas, liquid, or solid. This phenomenon of floating or suspending is called dispersion.
“Dispersoid and dispersion medium” are solid or liquid particles suspended and suspended in a dispersion system as a dispersoid or dispersion phase, and the medium is referred to as a dispersion medium.

According to the present invention, an aqueous liquid (dispersion medium or dispersoid) and a hydrophobic liquid that is incompatible with the aqueous liquid (dispersoid or dispersion) are obtained using a circulation type simple structure gas-liquid shearing type fluid mixing device. A stable emulsion at a submicron level can be obtained at low cost simply by circulating a liquid mixture comprising a medium for a short time.

FIG. 1 is a cross-sectional view showing a schematic configuration of a liquid mixing apparatus according to an embodiment of the present invention. It is sectional drawing of the venturi block integrated in the liquid mixing apparatus shown in FIG. 3 (A) to 3 (C), FIG. 3 (A) is a sectional view of the nozzle block incorporated in the liquid mixing apparatus of FIG. 1, and FIGS. 3 (B) and 3 (C) are others. It is sectional drawing of the nozzle block of a form. The graph which shows the relationship between air introduction amount and pump discharge amount. Microscope image of 1.0 vol% oleic acid / water emulsion: No air introduction 2 days after emulsification (A1), 1 month later (A2); Air introduction 2 days after emulsification (B1), 1 month later (B2). Diagram showing the results of emulsion stability test: No air introduction Immediately after emulsification (A1), 3 days later (A2), 2 months later (A3); Air introduction immediately after emulsification (B1), 3 days later (B2), 2 months Later (B3).

1. Hereinafter, an embodiment of a liquid mixing apparatus according to the present invention will be described with reference to the accompanying drawings.
[Outline configuration]
FIG. 1 shows a liquid mixing apparatus 10 according to an embodiment. The liquid mixing apparatus 10 generally includes a mixing unit 100, a pump unit 160, a liquid transfer unit 170, and a gas suction unit 180.

[Mixing unit]
The mixing unit 100 is configured by combining a plurality of blocks (a container block 110, a base block 120, a venturi block 131, a flow path block 150, etc.) described below.

The container block 110 forms a mixing chamber 111 for mixing two liquids as will be described later. For this purpose, the container block 110 of the embodiment is formed of a hollow cylindrical body, and is arranged with the central axis 112 of the hollow cylindrical body directed in the vertical direction.

The upper part of the container block 110 is covered with a lid 113. The lid 113 includes a pressure adjustment valve 114. A circular hole 115 is formed at the bottom of the container block 110 so as to penetrate the container bottom in the vertical direction along the central axis 112. The bottom surface of the container block 110 is configured by an inverted frustoconical inclined bottom surface 116 that gradually increases from the outer peripheral edge of the circular hole 115 toward the radially outer side.

The container block 110 is supported by the base block 120. In the base block 120, a circular hole 121 having a predetermined depth and having substantially the same cross section as the circular hole 115 is formed immediately below the circular hole 115 at the bottom of the container and adjacent thereto. One large vertical hole 122 is formed together with the circular hole 115 of the container block 110. The base block 120 also includes a flow path 123 extending from the bottom surface of the circular hole 121 to the bottom surface of the base block, and a gas supply hole 124 extending substantially horizontally from a substantially middle stage of the circular hole 121 toward the radially outer side.

The fine bubble supply unit 130 shown in FIG. 2 is detachably disposed in the vertical hole 122. In the embodiment, the fine bubble supply unit 130 includes a venturi block 131. The venturi block 131 is composed of a vertical cylindrical body made of a single material. The external shape of the venturi block 131 (in particular, the cylindrical outer peripheral surface and the circular bottom surface) substantially matches the shape of the vertical hole 122.

The venturi block 131 includes a flow path 132 formed by a hole penetrating the venturi block 131 in the vertical direction along the central axis of the venturi block 131. With the venturi block 131 attached to the base block 120, the central axis of the venturi block 131 coincides with the central axis 112 of the container block 110. The flow path 132 includes a lower flow path portion 133, a middle flow path portion 134, and an upper flow path portion 135. In the embodiment, the lower flow path portion 133 has a lower cylindrical portion and an upper truncated cone portion. The upper channel portion 135 has an upper cylindrical portion and a lower inverted truncated cone portion. The upper end of the lower channel truncated cone part and the lower end of the upper channel inverted truncated cone part have substantially the same circular cross section, and the middle channel part 134 is connected between them.

In the middle stage of the venturi block 131, one or a plurality of intake holes 136 extending from the middle flow path portion 134 toward the radially outer side are formed. These intake holes 136 are connected to a manifold 137 formed of an annular groove formed on the outer periphery of the venturi block 131. The manifold 137 is provided at a position connected to the gas supply hole 124 of the base block 120 in a state where the venturi block 131 is assembled to the base block 120 as shown in the figure.

A nozzle block 140 is disposed on the venturi block 131. As shown in FIG. 3A, the nozzle block 140 includes a flow channel 141 formed by a hole penetrating the nozzle block 140 in the vertical direction along the central axis in the vertical direction. The nozzle block 140 can be detachably fixed to the venturi block 131. For this purpose, for example, the nozzle block 140 is fixed to the venturi block 131 with a bolt, or a female screw portion is formed on one of the venturi block 131 and the nozzle block 140 and a male screw is formed on the remaining other, The nozzle block 140 is preferably detachable from the venturi block 131 by engaging a male screw.

The flow path 141 of the nozzle block 140 includes a lower flow path portion 142, a middle flow path portion 143, and an upper flow path portion 144. In the embodiment, the lower flow path portion 142 has a lower truncated cone portion and includes a spiral groove (spiral flow forming portion) 145 extending in the vertical direction along the inner surface of the cone. The upper channel portion 144 has an upper inverted truncated cone portion. The upper end of the lower channel truncated cone part and the lower end of the upper channel inverted truncated cone part have substantially the same circular cross section, and the middle channel part 143 is connected between them. Therefore, the lower end opening of the lower flow path portion 142 is connected to the upper end opening of the upper flow path portion 135 of the venturi block 131 in a state where the nozzle block is assembled to the venturi block 131.

Returning to FIG. 1, in the embodiment, a flow path block 150 is detachably attached under the base block 120. The flow path block 150 includes a flow path 151. The flow channel 151 forms one liquid supply flow channel 152 together with the flow channel 123 of the base block 120 in a state where the flow channel block 150 is combined with the base block 120.

As shown in the drawing, the flow path 151 of the flow path block 150 includes a vertical flow path portion 153 extending downward from the upper surface of the flow path block along the central axis 112 and the vertical flow path portion 153. A horizontal flow path portion 154 extends from the lower end to the flow path block side surface in the flow path block.

In the container block 110 and the base block 120, a liquid recovery channel 155 extending from the inclined bottom surface 116 of the container block 110 toward the outer peripheral side surface of the base block 120 is formed. The liquid recovery channel 155 includes an upper vertical channel portion 156 that passes through the inside of the container bottom from the container inclined bottom surface 116 toward the container bottom surface, and a lower vertical channel portion 157 that extends downward from the upper surface of the base block in the base block. , A horizontal flow path portion 158 extending from the lower end of the lower vertical flow path portion 157 in the base block to the side surface of the base block.

In order to prevent the drawing from becoming complicated, only one liquid recovery channel 155 is shown in FIG. 1, but a plurality of liquid recovery channels 155 may be provided evenly around the central axis.

Each of the plurality of blocks described above is detachably connected to an adjacent block by appropriate connection means. In addition, each of the plurality of blocks described above has an appropriate seal formed between adjacent blocks. For example, the base block contact surface of the container block 110 or the container contact surface of the base block 120 is formed with an annular groove (not shown) surrounding the vertical hole 122 and the liquid recovery channel 155, and a sealing member such as an O-ring is formed there. Is placed. Similarly, a tubular groove surrounding the liquid supply channel 152 is formed on the channel block contact surface of the base block 120 or the base block contact surface of the channel block 150, and a seal member such as an O-ring is disposed there. . Accordingly, liquid does not leak from the boundary between adjacent blocks.

[Pumping unit]
The pump unit 160 has a pump 161. The pump 161 may be any of a non-positive displacement pump, a positive displacement pump, and a special type pump. The non-displacement pump may be any of a centrifugal pump (a vortex pump and a diffuser pump), a mixed flow pump (a vortex pump and a diffuser pump), and an axial flow pump.

The pump 161 has a pump casing 162. The pump casing 162 includes a suction port 163, a discharge port 164, and a pump flow path 165 that connects the suction port 163 and the discharge port 164. The pump flow path 165 includes a drive unit 166 that sucks liquid from the suction port 163 and discharges liquid from the discharge port 164. For example, in the case of a centrifugal pump, the drive unit is an impeller, and this impeller is drivingly connected to a motor 167 provided outside the pump casing.

In the embodiment, a liquid extraction port 168 is provided at the lowest position of the pump flow path 165.

[Liquid transfer unit]
The liquid transfer unit 170 has a liquid supply pipe 171 and a liquid recovery pipe 172. The liquid supply pipe 171 having one end and the other end connects the pump discharge port 164 and the liquid supply channel 152, and connects the other end connected to the pump discharge port 164 to one end connected to the liquid supply channel 152. It is horizontal towards or has an upslope greater than 0 degrees. The liquid recovery pipe 172 having one end and the other end is horizontal from the other end connected to the pump suction port 163 toward one end connected to the liquid recovery flow path 155 or has an upward gradient exceeding 0 degree. .

[Gas intake unit]
The gas suction unit 180 has a gas suction pipe 181. One end of the gas suction pipe 181 is connected to the gas supply hole 124 of the venturi block 131, and the gas suction port 182 at the other end is opened to the atmosphere or connected to an appropriate gas cylinder (not shown). Yes. The gas suction pipe 181 includes a flow rate adjustment valve 183, a flow rate sensor 184, and a check valve 185 in order from the other end (the gas suction port 182) toward one end.

[motion]
An emulsification process for obtaining an emulsion by dispersing a hydrophobic liquid (dispersoid) in an aqueous liquid (dispersion medium) using the liquid mixing apparatus 10 having the above configuration will be described.

In the emulsification process, a liquid mixture 190 in which an aqueous liquid and a hydrophobic liquid are mixed at a predetermined ratio is accommodated in the mixing chamber 111 and the pump 161 is driven. Thereby, the mixed liquid 190 in the mixing chamber 111 is discharged from the discharge port (exit) 117 formed on the inclined bottom surface 116 of the container block 110 (that is, the upper end opening of the upper vertical channel portion 156 passing through the container bottom). Then, the liquid is sucked into the pump flow path 165 through the liquid recovery path 155 and the liquid recovery pipe 172, and then through the liquid recovery path 192 until reaching the pump suction port 163.

The mixed liquid 190 sucked into the pump 161 passes through the pump flow path 165 and is discharged from the discharge port 164.

The liquid mixture discharged from the pump discharge port 164 is sent from the pump discharge port 164 to the flow channel 132 of the venturi block 131 through the liquid supply pipe 171 and the liquid supply flow channel 152. The mixed liquid 190 that has reached the venturi block 131 passes from the lower flow path portion 133 having a large cross section through the middle flow path portion 134 having a small cross section and enters the upper flow path portion 135 having a large cross section. At this time, when the flow rate of the mixed liquid passing through the middle flow path portion 134 increases, a negative pressure is generated in the intake hole 136 opened to the middle flow path portion 134. As a result, the gas sucked through the gas suction pipe 181 is mixed with the mixed liquid 190 flowing through the middle flow path portion 134 from the suction hole 136.

The amount of gas sucked from the gas suction pipe 181 can be adjusted by the flow rate adjustment valve 183 while watching the output of the flow rate sensor 184.

When the gas mixed in the liquid mixture 190 enters the upper flow path portion 135, a vortex is generated to form a strong shear field. As a result, the sucked gas is refined, and a mixed liquid containing a large amount of microbubbles or ultrafine bubbles (including both of them is referred to as “fine bubbles”) is generated. At the same time, the liquid mixture is subjected to a strong shearing action in the presence of fine bubbles, and the hydrophobic liquid is dispersed in the aqueous liquid.

When the liquid mixture containing a large amount of fine bubbles is sent from the venturi block 131 to the flow path 141 of the nozzle block 140, it is affected by the liquid rising along the spiral groove 145 formed on the inner peripheral surface of the nozzle block 140. Thus, a spiral upward flow (that is, a shearing field) is formed, and is injected into the mixing chamber 111 from the upper end injection port 146 (inlet) of the nozzle block 140 (see FIG. 3). As described above, the liquid mixture and the fine valve transferred through the liquid supply path 191 from the discharge port 164 of the pump 161 to the upper end injection port 146 of the nozzle block 140 are injected from the upper end injection port 146 into the mixing chamber 111. A spiral jet is formed. Therefore, the liquid mixture injected into the mixing chamber 111 is subjected to a shearing action again in the presence of fine bubbles. As a result, the hydrophobic liquid is further uniformly dispersed in the aqueous liquid.

The mixed liquid 190 injected from the nozzle block 140 into the mixing chamber 111 rises from the upper end injection port 146 of the nozzle block 140 upward in the injection region 193 that spreads in a spindle shape. At this time, the relatively large bubble is moved upward in the mixing chamber 111 under the influence of buoyancy and reaches the water surface. On the other hand, the fine bubbles contained in the mixed liquid descend on the downward flow (swirl flow) of the mixed liquid formed in the mixing chamber 111 and recover the liquid from the discharge port 117 formed on the inclined bottom surface 116 at the bottom of the container. It is taken out to the flow path 155.

Thereafter, the liquid mixture 190 sent from the liquid recovery flow path 155 through the liquid recovery pipe 172 and sent from the suction port 163 to the flow path 165 in the pump 161 is again subjected to a strong shearing action by the impeller 166 rotating in the pump 161. The hydrophobic liquid is further dispersed in the aqueous liquid.

Thus, according to the liquid mixing apparatus of the above-described embodiment, the hydrophobic liquid is uniformly dispersed in the aqueous liquid in the presence of the fine bubbles. In particular, in the above-described embodiment, since the discharge port 117 for sucking out the mixed liquid from the mixing chamber 111 is disposed outside the injection region 193, the large size contained in the mixed liquid 190 injected into the mixing chamber 111 from the injection port 146. Bubbles are not sent to the pump 161 through the outlet 117. Therefore, a strong shear field is formed in the pump 161, and the dispersion of the hydrophobic liquid is remarkably improved.

The mixed liquid in which the hydrophobic liquid is uniformly dispersed in the aqueous liquid as described above is extracted from the liquid extraction port 168 of the pump 161. At this time, as shown in FIG. 1, since the liquid extraction port 168 is provided at the lowest position of the liquid mixing device 10, when the liquid extraction port 168 is opened, the liquid mixture present in each part of the liquid mixing device 10 is All gather at the liquid extraction port 168. Therefore, the subsequent disassembly and cleaning can be easily performed.

In addition, it is preferable that at least a portion in contact with the liquid mixture in the liquid mixing apparatus is made of a stainless material so that the emulsified liquid mixture does not contain impurities.

The liquid mixing apparatus described above can be variously modified.

For example, in the above-described embodiment, a spiral flow of the mixed liquid is formed by forming a truncated cone-shaped flow path in the nozzle block 140 and forming a spiral groove on the inner surface of the flow path. Can be formed. For example, the nozzle block 240 shown in FIG. 3B includes an internal helical helical gear (helical bevel gear) 241 or a spiral bevel gear (spiral bevel gear) having a predetermined pitch cone angle and the number of teeth. An externally toothed helical bevel gear (helical bevel gear) 242 or spiral bevel gear (spiral bevel gear) having the same number of teeth and pitch cone angle as the bevel gear is configured, and the gap between the teeth of these two gears The mixed liquid is jetted from to form a spiral flow. FIG. 3C shows an example in which the nozzle block is constituted by a spiral nozzle 340.

In the above-described embodiment, the venturi method is used to generate fine bubbles, but other methods such as a pressure dissolution method, a cavitation method, an ejector method, a swirl flow method, and a static mixer method are adopted. Also good.

In the above-described embodiment, the mixed liquid is jetted upward from the bottom of the mixing chamber. However, the jet port is disposed on the side wall of the mixing chamber, and the jet port is directed horizontally or obliquely upward with respect to the mixing chamber. You may inject a liquid mixture.

2. Effect of gas introduction in the liquid mixing apparatus according to the present invention The inventor of the present invention is a table-type gas-liquid shearing type fluid mixing having a size of width 320 mm × depth 250 mm × height 250 mm and a weight of about 15 kg. A device was made. The internal structure is the same as that of the liquid mixing apparatus 10 shown in FIG. 1, but in order to investigate the gas introduction method, a gas supply unit similar to the gas supply unit 180 is provided immediately before the pump inlet 163 and liquid. Mounted on the collection tube 172 (not shown).

In the above fluid mixing device, the influence on the pump performance by the place of gas introduction was investigated. In Examples and Comparative Examples, since air is used as the gas to be introduced, it is referred to as “air introduction”. A flow meter for measuring the flow rate is installed between the pump discharge port 164 and the fluid supply flow path 152, that is, on the liquid supply pipe 171, and a sufficient amount of water is introduced into the mixing chamber 111, and the pump motor is 4,000 rpm. The water was circulated. In the use of the liquid mixing apparatus of the present invention, the “sufficient amount” means an amount capable of forming an injection region in which the liquid mixture injected from the nozzle block into the mixing chamber forms a spindle shape upward from the upper end injection port of the nozzle block. Say. The distance from the upper end of the discharge port formed on the inclined bottom surface of the container block to the water surface is changed to 50 mm or more, preferably 100 mm or more by changing the cross-sectional area inside the mixing chamber according to the amount of liquid to be charged. To be.

Comparative Example 1: Air introduction from the upstream side of the pump For comparison, the fluctuation of the pump discharge amount when the air was introduced from the upstream side of the pump by the gas supply unit (supply unit A) attached immediately before the pump suction port 163 was examined. A result is shown in Table 1, and the graph which plotted the pump discharge amount decreasing rate as a function of the air introduction amount is shown in FIG.

Example 1: Air introduction from downstream of pump According to the present invention, Table 2 shows the results of examining the variation in pump discharge when air is introduced from downstream of the pump by gas supply unit 180 (gas supply unit B). FIG. 4 shows a graph in which the pump discharge rate reduction rate is plotted as a function of the air introduction amount.

As can be seen from Tables 1 and 2 and the graph of FIG. 4, it was confirmed that when air was introduced from the downstream side of the pump according to the present invention, a phenomenon that adversely affected the pump discharge rate did not occur.

3. Preparation of emulsion using liquid mixing apparatus according to the present invention A method for preparing an emulsion according to the present invention comprises at least a mixing chamber having an inlet and an outlet, and a pump having an inlet and an outlet, The suction port is fluidly connected, the discharge port and the inlet are fluidly connected, and based on the driving of the pump, the mixed liquid stored in the mixing chamber is sucked from the outlet, After the fine bubbles are discharged from the discharge port via the pump and supplied to the discharged mixed liquid, the mixed liquid supplied with the fine bubbles is injected into the mixing chamber and then injected into the mixing chamber. A method of preparing an emulsion using a liquid mixing apparatus, characterized in that the outlet is arranged outside a jetting region of a mixed liquid,
The mixed liquid includes an aqueous liquid and a hydrophobic liquid that is incompatible with the aqueous liquid, and is added to a surfactant and an emulsion having a function of reducing interfacial tension at the interface between the aqueous liquid and the hydrophobic liquid. However, it does not contain an additive selected from any one of salts, hydrogen-bonding molecules, and alcohols among those that do not have an effect of reducing the interfacial tension.

Preparation of the emulsion according to the present invention is not limited, but the liquid mixing apparatus 10 according to the present invention is used. An emulsion of 1.0% by volume of water and oleic acid was prepared using the fluid mixing apparatus according to the present invention. Tank 1 was charged with 990 L of water and oleic acid 10 L. Thereafter, the liquid was circulated for 10 minutes at a pump motor of 4,000 rpm.

Comparative Example 2: Preparation of emulsion without air introduction For comparison, liquid was circulated without air introduction. After 10 minutes, the liquid extraction port 168 was opened and the emulsion was taken out.
Two days and one month after removal, when the obtained solution was observed using a microscope (VHX-6000 manufactured by KEYENCE) (FIG. 5-A1, A2), only a very heterogeneous emulsion was obtained. Not confirmed. Note that no bubbles were observed with the microscope.
According to visual observation, it was an emulsion solution in which the whole was uniformly emulsified immediately after removal (FIG. 6-A1). This emulsion was put in a reagent bottle, sealed, and allowed to stand at room temperature (about 25 ° C.) for 3 days. As a result, a white turbid phase and a transparent phase (not transparent in the true sense, (Representing an extremely low phase) was observed (Fig. 6-A2), and after standing for 2 months, complete phase separation between water and oleic acid was observed (Fig. 6-A3). It was found to be an unstable emulsion.

Example 2 Preparation of Emulsion with Air Introduction According to the present invention, the liquid was circulated while introducing air at 100 cc / min from the downstream of the pump in the fine bubble supply unit 130. After 10 minutes, the liquid extraction port 168 was opened and the emulsion was taken out.
Two days and one month after removal, the obtained solution was observed using a microscope (VHX-6000 manufactured by KEYENCE) (FIG. 5-B1, B2). It was confirmed that a finely dispersed emulsion was obtained. By image analysis, the average diameter of the emulsion was 0.73 μm. Note that no bubbles were observed with the microscope.
According to visual observation, immediately after removal, the emulsion solution was uniformly emulsified (FIG. 6-B1). The emulsion was sealed in a reagent bottle and allowed to stand at room temperature (about 25 ° C.) for 3 days, but no separation between the cloudy phase and the transparent phase was observed (FIG. 6-B2), and the emulsion was allowed to stand for 2 months. After installation, neither the above-mentioned separation nor the phase separation of water and oleic acid was observed (FIG. 6-B3), and it was found that the emulsion was very stable.

Since the fluid mixing apparatus according to the present invention does not have a complicated mechanism, it can be reduced in size and weight, and a stable emulsion composed only of necessary aqueous liquid and hydrophobic liquid can be easily obtained without using any additive. And can be prepared quickly. That is, it is suitable for research and development because it is possible to produce a large variety of small amounts of emulsion. In product development, it is possible to respond immediately to consumer demand and provide it on the spot. For example, since preservatives are not required for cosmetics, it is best for consumers who are sensitive to chemical substances. Products can be provided. Furthermore, the cosmetics etc. which a consumer contains only the component which a consumer desires can also be created.
In addition, with the global warming and airtightness of houses, demand for sanitary pest control is increasing. This is because pest control using a chemical agent, which has been a powerful technique in the past, is harmful to humans, and in recent years, the usage fee has decreased, and human-friendly product development is required. By using the technology of the present invention, a small apparatus can be brought into the field, and an insecticidal action emulsion composed of only natural active ingredients and water can be prepared on the spot to carry out the control work. For example, in the endemic areas of malaria, the use of emulsion insect repellents prepared by local people on mosquito nets is expected to promote the eradication of diseases.

10: Liquid mixing device 100: Mixing unit 110: Container block 111: Mixing chamber 112: Center shaft 113: Lid 114: Pressure adjusting valve 115: Circular hole 116: Inclined bottom surface 117: Discharge port (exit)
120: base block 121: circular hole 122: vertical hole 123: flow path 124: gas supply hole 130: fine bubble supply part 131: venturi block 132: flow path 133: lower flow path part 134: middle flow path part 135: upper flow Road portion 136: Intake hole 137: Manifold 140: Nozzle block 141: Channel 142: Lower channel portion 143: Middle channel portion 144: Upper channel portion 145: Groove (spiral flow forming portion)
146: Upper end injection port (inlet)
150: Channel block 151: Channel 152: Liquid supply channel 153: Vertical channel portion 154: Horizontal channel portion 155: Liquid recovery channel 156: Upper vertical channel portion 157: Lower vertical channel portion 158: Horizontal Channel portion 160: Pump unit 161: Pump 162: Pump casing 163: Suction port 164: Discharge port 165: Pump channel 166: Drive unit 167: Motor 168: Liquid extraction port 170: Liquid transfer unit 171: Liquid supply pipe 172 : Liquid recovery pipe 180: Gas suction unit 181: Gas suction pipe 182: Gas suction port 183: Flow rate adjustment valve 184: Flow rate sensor 185: Check valve 190: Liquid mixture 191: Liquid supply path 192: Liquid recovery path 193: Injection region

Claims

A mixing chamber (111) with an inlet (146) and an outlet (117);
A liquid supply path (191), wherein the liquid supply path (191) has one end and the other end, and the one end of the liquid supply path (191) is connected to the inlet (146) ( 191),
A liquid recovery path (192), wherein the liquid recovery path (192) has one end and the other end, and the one end of the liquid recovery path (192) is connected to the outlet (117) ( 192),
It has a suction port (163) and a discharge port (164), the other end of the liquid recovery path (192) is connected to the suction port (163), and the liquid supply path (191) is connected to the discharge port (164). A pump (161) connected to the other end of
Based on the driving of the pump (161), a mixed liquid (190) of two liquids stored in the mixing chamber (111) is sucked from the outlet (117), and the liquid recovery path (192), A liquid mixing device (10) for injecting from the inlet (146) to the mixing chamber (111) via a pump (161) and the liquid supply path (191);
The liquid mixing device (10) includes a fine bubble supply unit (130) including a venturi block (131) for supplying fine bubbles to the mixed liquid (190) flowing through the liquid supply path (191).
The liquid mixing device (10) further includes a gas suction unit having a gas suction pipe (181). One end of the gas suction pipe (181) has a gas supply hole (124) of the venturi block (131). ), The gas inlet (182) at the other end is opened to the atmosphere, or connected to a gas cylinder,
An outlet (117) of the mixing chamber (111) is disposed outside an injection region (193) of the mixed liquid (190) injected from the inlet (146) of the mixing chamber (111) into the mixing chamber (111). Has been
The fine bubble supply channel (130) includes a spiral flow forming unit that imparts a spiral motion around the central axis (112) of the inlet (146) to the mixed liquid (190) flowing toward the inlet (146). Has
The spiral flow forming part is
(A) a spiral flow forming portion in which a spiral groove is formed on the inner surface of a truncated cone-shaped channel whose inner diameter gradually decreases toward the inlet (146);
(B) An internal bevel gear comprising a helical bevel gear or a spiral bevel gear having a predetermined number of teeth and a predetermined pitch cone angle, and an outer having the same number of teeth and the same pitch cone angle as the internal gear bevel gear. The tooth-shaped bevel gear is placed on the inner-tooth bevel gear and the teeth of the inner-tooth bevel gear are engaged with the teeth of the inner-tooth bevel gear and the teeth of the outer-tooth bevel gear. A liquid mixing apparatus, wherein the liquid mixing device is either a spiral flow forming portion in which a spiral gap is formed between teeth of a tooth bevel gear, or (c) a spiral flow forming portion including a spiral nozzle (340).
The spiral flow forming part is
(B) An internal bevel gear comprising a helical bevel gear or a spiral bevel gear having a predetermined number of teeth and a predetermined pitch cone angle, and an outer having the same number of teeth and the same pitch cone angle as the internal gear bevel gear. The tooth-shaped bevel gear is placed on the inner-tooth bevel gear and the teeth of the inner-tooth bevel gear are engaged with the teeth of the inner-tooth bevel gear and the teeth of the outer-tooth bevel gear. It is either a spiral flow formation part which formed the helical clearance gap between the teeth of the tooth bevel gear, or (c) the spiral flow formation part which consists of a spiral nozzle (340), It is characterized by the above-mentioned. The liquid mixing apparatus as described.
The liquid mixing apparatus according to claim 1 or 2, wherein the fine bubble supply unit (130) is provided in the liquid supply path (191).
The liquid supply path (191) includes a liquid supply flow path (152) and a liquid supply pipe (171) having one end and the other end, and the liquid supply pipe (171) is connected to the pump discharge port (164). From the other end connected to the liquid supply flow path (152) to the one end connected to the liquid supply flow path (152) or having an upward slope exceeding 0 degrees, the liquid recovery path (192) A liquid recovery pipe (172) having a path (155) and one end and the other end, and the liquid recovery pipe (172) is connected to the pump suction port (163) from the other end. The liquid mixing apparatus according to any one of claims 1 to 3, wherein the liquid mixing apparatus is horizontal toward one end connected to 155) or has an upward gradient exceeding 0 degree.
The pump (161)
A pump casing (162) comprising a pump suction port (163), a pump discharge port (164), a pump flow path (165) connecting the pump suction port (163) and the pump discharge port (164),
A drive unit (166) disposed in the pump flow path (165) and configured to transfer a mixed liquid from the pump suction port (163) toward the pump discharge port (164);
A liquid extraction port (168) for extracting the mixed liquid of the pump flow path (165),
The liquid mixing apparatus according to claim 4, wherein the liquid extraction port (168) is provided at a lowermost position of the pump flow path (165).
At least a mixing chamber having an inlet and an outlet, a pump having a suction port and a discharge port, a fine bubble supply unit, and a gas suction pipe, wherein the outlet and the suction port are fluidly connected, and The discharge port and the inlet are fluidly connected, and based on the driving of the pump, the mixed liquid stored in the mixing chamber is sucked from the outlet and discharged from the discharge port through the pump. The fine bubble supply unit includes a venturi block, and one end of the gas suction pipe is connected to the gas supply hole of the venturi block, and the gas suction port at the other end is opened to the atmosphere, or a gas cylinder is provided. After the fine bubbles are supplied by the gas sucked from the gas supply holes through the gas suction pipe being mixed with the discharged mixed liquid, The mixed liquid supplied with the liquid is injected into the mixing chamber to form a spiral injection flow, and the outlet is disposed outside the injection region of the mixed liquid injected into the mixing chamber. A method of preparing an emulsion using a liquid mixing device, comprising:
The method for preparing an emulsion, wherein the mixed liquid comprises an aqueous liquid and a hydrophobic liquid that is incompatible with the aqueous liquid.
The method for preparing an emulsion according to claim 6, wherein the liquid mixing apparatus according to any one of claims 1 to 5 is used.