Nozzle for Liquid Phase Ejection
20210197145 · 2021-07-01
Inventors
- Hirochika NAGANAWA (Tokai-mura, Nakagun Ibaraki, JP)
- Tetsushi NAGANO (Tokai-mura, Nakagun Ibaraki, JP)
- Hirofumi ITO (Tokyo, JP)
- Ryosuke SATO (Kasama-shi, Ibaraki-ken, JP)
Cpc classification
B01F35/7182
PERFORMING OPERATIONS; TRANSPORTING
Y02P10/20
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B01F2101/2204
PERFORMING OPERATIONS; TRANSPORTING
B01F25/31331
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A nozzle for spouting a liquid phase, in which one liquid phase in a two-liquid phase system can be stably jetted as highly dispersible droplets while suppressing coalescence of droplets, and accumulation of fine solid components in the nozzle hardly occurs. The nozzle has a structure in which capillary tubes or pores are assembled. Further, the capillary tubes or the pores are formed using a suitable material having a low affinity for organic or a low affinity for water, or a material subjected to appropriate surface treatment.
Claims
1.-20. (canceled)
21. A nozzle for spouting a liquid phase comprising: at least one structure for spouting a first liquid phase to a second liquid phase in a two-liquid phase system including an aqueous phase and an organic phase, in which a plurality of capillary tubes or pores that are open at both ends are assembled, wherein the two-liquid phases are brought into an emulsion state by spouting the first liquid phase sucked from a first end of said structure into the second liquid phase in the form of droplets from a second end of said structure.
22. The nozzle for spouting a liquid phase according to claim 21, wherein by using a material with a low affinity for an organic phase or a material with a low affinity for an aqueous phase as the capillary or the pores, a droplet is formed and spouted so as to form an emulsion state while suppressing coalescence of the droplets when the droplets of the organic phase or the aqueous phase are spouted.
23. The nozzle for spouting a liquid phase according to claim 21, wherein by applying a material with a low affinity for an organic phase or a material with a low affinity for an aqueous phase to the surface of the tip of the capillary or the pores, the coalescence of the droplets is suppressed when the droplets of the organic phase or the aqueous phase are spouted, and both phases become an emulsion state.
24. A nozzle for spouting a liquid phase, the nozzle comprising: a plurality of capillary tubes or pores, each with an inner diameter of 0.5 mm or less, which spouts the liquid phase in a two-liquid phase system having an aqueous phase and an organic phase containing at least one of the particle components, both ends of a suction end for sucking the liquid phase and a nozzle discharge end for releasing the sucked liquid phase are open, the capillary tubes or the pores, in which the total length of the cylindrical or tunnel-shaped portion between the openings is at least twice the inner diameter, and the inner diameter is at least five times a maximum particle diameter of the particle component, are assembled, and an emulsion state is formed by spouting the aqueous phase or organic phase containing particle components as droplets from the nozzle discharge end into the other liquid phase, resulting in an emulsion generated.
25. The nozzle for spouting a liquid phase according to claim 24, wherein a structure in which the capillary tubes or the pores are assembled includes a casing container that entirely covers a suction end for sucking the liquid phase, and a liquid feeding pipe that sends an aqueous phase or an organic phase is attached to the casing container.
26. The nozzle for spouting a liquid phase according to claim 24, wherein the length of the capillary tubes or pores protruding to the open side of the structure in which the capillary tubes or the pores are assembled is not constant, and the capillary tubes or pores having different total lengths are mixed.
27. The nozzle for spouting a liquid phase according to claim 24, wherein said nozzle is composed of two or more units each having a same number or different numbers of the capillary tubes or the pores, with a structure in which two or more capillary tubes or pores are assembled as a unit.
28. The nozzle for spouting a liquid phase according to claim 27, wherein for one container filled with an aqueous phase or an organic phase, two or more of the units are installed so as to share the container, and the liquid feeding pipe is attached to the shared container.
29. The nozzle for spouting a liquid phase according to claim 27, wherein the liquid feeding pipe is branched into two or more branches, and one of the units is installed at each branch destination.
30. The nozzle for spouting a liquid phase according to claim 24, wherein by using a material with a low affinity for an organic phase or a material with a low affinity for an aqueous phase as the capillary tubes or the pores, a droplet is formed and spouted so as to form an emulsion state while suppressing coalescence of the droplets when the droplets of the organic phase or the aqueous phase are spouted.
31. The nozzle for spouting a liquid phase according to claim 24, wherein by applying a material with a low affinity for an organic phase or a material with a low affinity for an aqueous phase to the surface of the tip of the capillary tubes or the pores, the coalescence of the droplets is suppressed when the droplets of the organic phase or the aqueous phase are spouted, and both phases become an emulsion state.
32. A nozzle for spouting a liquid phase, wherein said nozzle is installed in an aqueous phase or an organic phase in a two-liquid phase system consisting of the aqueous phase and the organic phase, said nozzle has a structure including a plurality of small tubes or pores assembled at both ends of a suction end for sucking a liquid phase and a nozzle discharge end for releasing the sucked liquid phase are open, and an entire length of a tubular or tunnel-shaped portion having an inner diameter of 0.5 mm or less is at least twice as long as the inner diameter, and an emulsion state is formed by spouting the aqueous phase or the organic phase as droplets from the nozzle discharge end into the other liquid phase, resulting in an emulsion.
33. The nozzle for spouting a liquid phase according to claim 32, wherein said nozzle comprises a plurality of capillary tubes or pores, each with an inner diameter of 0.5 mm or less, which spouts the liquid phase in a two-liquid phase system having an aqueous phase and an organic phase containing at least one of particle components, both ends of the suction end for sucking the liquid phase and the discharge end for releasing the sucked liquid phase are open, the capillary tubes or the pores, in which the total length of the cylindrical or tunnel-shaped portion between the openings is at least twice the inner diameter, and the inner diameter is at least five times a maximum particle diameter of the particle components, are assembled, and an emulsion state is formed by spouting the aqueous phase or organic phase containing the particle components as droplets from the nozzle discharge end into the other liquid phase, resulting in an emulsion.
34. The nozzle for spouting a liquid phase according to claim 32, wherein a length of the capillary tubes or pores protruding to the open side of the structure in which the capillary tubes or the pores are assembled is not constant, and the capillary tubes or pores having different total lengths are mixed.
35. The nozzle for spouting a liquid phase according to claim 32, wherein said nozzle is composed of two or more units each having a same number or different numbers of the capillary tubes or the pores, with a structure in which two or more capillary tubes or pores are assembled as a unit.
36. The nozzle for spouting a liquid phase according to claim 35, wherein for one container filled with the aqueous phase or the organic phase, two or more of the units are installed so as to share the container, and a liquid feeding pipe is attached to the shared container.
37. The nozzle for spouting a liquid phase according to claim 36, wherein the liquid feeding pipe, which sends the aqueous phase or the organic phase, is branched into two or more branches, and the unit is installed at each branch destination.
38. The nozzle for spouting a liquid phase according to claim 32, wherein by using an organic or hydrophobic material as the capillary or the pores, the coalescence of the droplets is suppressed when the droplets of the organic phase or the aqueous phase are spouted, and both phases become an emulsion state.
39. The nozzle for spouting a liquid phase according to claim 32, wherein by processing a surface of a tip portion of the capillary tubes or the pores with an organic-phobic treatment or a hydrophobic treatment, the coalescence of the droplets is suppressed when the droplets of the organic phase or the aqueous phase are spouted, and both phases become an emulsion state.
40. A nozzle for spouting a liquid phase as droplets, comprising: a plurality of capillary tubes or pores in which both ends of a suction end for sucking the liquid phase and a discharge end for releasing the sucked liquid phase are open, and an entire length of a cylindrical or tunnel-shaped portion having an inner diameter of 0.5 mm or less is at least twice as long as the inner diameter are assembled, wherein each of the plurality of the capillary tubes or the pores is assembled at a predetermined interval such that the droplets spouted from the nozzle do not coalesce.
Description
BRIEF DESCRIPTION OF THE SEVERAL DRAWINGS
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BEST MODE FOR CARRYING OUT THE INVENTION
[0050] Before describing the structure of the nozzle according to the present invention, a counter current type emulsion flow apparatus will be described with reference to
[0051] In
[0052] Next, the operation will be described. The aqueous phase is supplied to the aqueous phase spouting nozzle of the emulsion flow apparatus 100 by an aqueous phase supply pump provided in a pipe connecting the supply aqueous phase (aqueous solution) and the emulsion flow apparatus 100, and the aqueous phase is extracted into an organic phase as an extraction solvent. At the same time, the organic phase is jetted through the organic phase spouting nozzle of the apparatus 100 so as to face the flow of the aqueous solution. As a result, a flow (emulsion flow) composed of an emulsion mixed phase of an aqueous phase and an organic phase is generated in the two-liquid phase mixing part of the emulsion flow apparatus 100. When the emulsion flow reaches the organic phase separation part above the two-liquid phase mixing part and the aqueous phase separation part below the two-liquid phase mixing part, the state of the emulsion flow is released and the aqueous phase and the organic phase are separated. As a result, the organic phase gathers in the organic phase separation part, and the aqueous phase gathers in the aqueous phase separation part. The clean organic phase in the organic phase separation part is circulated through the organic phase circulation line. Further, the clean aqueous phase in the aqueous phase separation part is taken out as the discharge aqueous phase after the treatment.
[0053] The emulsion generation nozzle according to the present invention, which will be described in detail below, is used as the above-described aqueous phase spouting nozzle and/or the organic phase spouting nozzle. As examples of the emulsion generating nozzle of the present invention, a bundled capillary tube nozzle (
[0054] Further, it is preferable that the discharge pressure of the pump is set as low as possible within a range in which droplets can be generated. If the pump discharge pressure becomes too large, the spouting of the liquid phase becomes jet flow, and the particle size distribution and shape of the droplet cannot be maintained properly. The optimum pump discharge pressure for spouting droplets greatly varies depending on the inner diameter of a capillary tube or a pore forming a nozzle, the physical properties (particularly, the viscosity) of a liquid phase to be discharged.
[0055] The bundled capillary tube nozzle shown in
[0056] Further, in a structure body in which capillary tubes or fine pores are assembled, it is possible to change the position and timing of spouting of the droplets by mixing capillary tubes or pores having different total lengths. Thereby, the isolation of the droplets is improved, and the coalescence of the droplets can be suppressed. However, when the lengths of the capillary tubes or the pores are significantly different, the difference in pressure loss becomes large, and the spouting of droplets may be biased. From this viewpoint, it is preferable that the change in the length of the capillary tubes or the pore is kept to a necessary minimum.
[0057]
[0058] Compared with a nozzle in which capillary tubes or pores are installed at an arbitrary distance, the nozzle in which the capillary tubes or the pores are in close contact with each other has an advantage that the liquid feeding amount per unit sectional area on the upper surface of the casing container can be increased. On the other hand, such a nozzle has a disadvantage that the droplets are likely to come into contact with each other and coalesce. Therefore, by installing a spacer for securing a distance between the capillary tubes in the case of a capillary tube nozzle, it is possible to suppress coalescence of droplets while maintaining the liquid feeding amount.
[0059] The spacer can be provided for both the bundled capillary nozzle and the protruding capillary nozzle. For example, the spacer used in the bundled capillary nozzle includes a separated type spacer separated from the fusion portion and an integrated type spacer coupled to the fusion portion. An example of the separated type spacer is shown in
[0060] The separated type spacer has a drawback in that a gap in which dense capillary tubes are exposed is formed between the fusion portion and the spacer, and solid components and/or oil components are easily collected in the gap. On the other hand, the integrated type spacer fills gaps between the fused portions and the spacer, and integrates the fused portion and the spacer. An example of an integrated type spacer is shown in
[0061] The spacer can also be used for a structure in which capillary tubes of different lengths are mixed. By making the lengths of the capillary tubes different, the effect of changing the position and timing of the spouting of the droplets and the effect of securing the distance between the capillary tubes by the spacer are also combined. Thereby, the isolation of the spouted droplets may be further improved.
[0062]
[0063] Scaling up the nozzle of the present invention becomes possible by increasing the number of capillary tubes or pores. However, the structure in which a relatively small number of capillary tubes or pores are assembled is regarded as one unit, and by combining a plurality of units, more efficient liquid feeding may be realized. This is because a sudden change in the inner diameter of the capillary tube or the pore when reaching the capillary tube or the pore from the liquid feeding pipe is reduced by passing through such a unit. That is, a rapid change in the linear velocity is reduced by a two-step inner diameter change, that is, a change in the inner diameter from the liquid feeding pipe to the unit and a change in the inner diameter from the unit to the capillary tube or pore. Also, if the nozzle is manufactured by combining such units, it is possible to easily cope with a change in specifications by changing the number of units, and it is not always necessary to replace the entire nozzle at the time of maintenance. For example, it is also possible to check the status of individual unit and replace only those parts where a problem is found.
[0064] Specifically, a structure body in which two or more capillary tubes or pores are assembled is used as one unit, and two or more units each including the same number or a different number of capillary tubes or pores are combined. The number of the capillary tubes or the pores constituting the unit is determined according to the size of the area of the droplet spouting surface and the number of units to be installed.
[0065] Further, as a nozzle structure having a plurality of units, for example, there is a method of installing a plurality of units so as to share one container. The shared container is provided with a liquid feeding pipe, and its pipe functions also as a nozzle. Specific examples are shown in
[0066] In addition to the above, there is also a way in which a liquid feeding pipe is branched into two or more tubes and the unit is installed at each branch destination as a nozzle structure having a plurality of units. Specific examples are shown in
[0067] With regard to materials for the nozzle droplet spouting part, in order to achieve a stable emulsion state, selection of suitable materials for the solvent and/or appropriate surface treatment is required, taking not only hydrocarbon solvents, but also highly polar solvents such as alcohols and ketones.
[0068] In other words, by using an organic-phobic material for the organic phase spouting nozzle and a hydrophobic material for the aqueous phase spouting nozzle as the material of the capillary tubes or pores forming the nozzle, droplets of the organic phase or aqueous phase are spouted. The droplets can be spouted while suppressing the coalescence of the droplets at the time of performing. The term “organophobic” is an antonym for “organophilicity” and is the same as “hydrophobic” for hydrophilicity. In addition, organophobic is a word corresponding to oil repellency (oil repelling property) to kerosene, etc.
[0069] Further, it is not always necessary to use an organophobic or hydrophobic material for the entire capillary or pore, the effect of suppressing coalescence of droplets can also be obtained by applying organophobic treatment or hydrophobic treatment on the surface of the tip of the capillary tube or the pore.
Embodiment 1
[0070] Effect of Accumulation of Fine Solid Components
[0071] The effects of the accumulation of fine solid components will be specifically described below with reference to examples, but the present invention is not limited to the following examples.
[0072] Using the nozzle shown in
[0073] The nozzle of the present invention shown in
[0074] As the aqueous phase, an aqueous nitric acid solution (pH 2) in which aluminum oxide fine powder was suspended was prepared, and as the organic phase, D70 (trade name: D70) which is one of alkane solvents was prepared. The aluminum oxide fine powder was prepared by drying a commercial product in a desiccator containing phosphorus pentoxide overnight, and then classifying.
[0075] Specifically, classification was performed using two types of stainless steel sieves having openings of 0.025 mm and 0.045 mm. First, aluminum oxide fine particles having a particle size exceeding 0.045 mm were removed (remained on the sieve) using a sieve having an opening of 0.045 mm, and fine particles that passed through the sieve were collected. Further, using a sieve having an opening of 0.025 mm, aluminum oxide fine particles having a particle size of 0.025 mm or less were removed (pass through the sieve), and only a size of 0.025 mm or more and 0.045 mm or less was classified (The fine particles remaining on the sieve were collected).
[0076] At the start of the experiment, an aqueous nitric acid solution (pH 2) as an aqueous phase and D70 as an organic phase were charged into an emulsion flow apparatus. The aqueous phase filled at the start of the experiment is, so to speak, a blank solution, which is an aqueous solution containing no aluminum oxide fine powder. Both liquid phases were filled so that the liquid-liquid interface was located at the center of the two-liquid phase mixing part. The organic phase was filled so that the tip of the liquid suction port located above the organic phase circulation liquid feeding line was immersed in a length of 10 mm or more, and a certain amount of air layer was provided above the apparatus.
[0077] On the other hand, a container filled with an aqueous nitric acid solution containing aluminum oxide fine powder to be treated was separately prepared, and connected to a pump (aqueous phase supply pump) for supplying an aqueous phase to the emulsion flow apparatus. The organic phase was connected to a pump (organic phase circulation pump) so as to circulate inside the apparatus without being supplied from outside. A commercially available diaphragm pump or peristaltic pump was used as the liquid feeding pump, but the same type of pump was used for sending the aqueous phase and the organic phase (the diaphragm pump and the peristaltic pump were not mixed).
[0078] During the experiment, both the aqueous phase and the organic phase were fed at a rate of 10 L/hour. With the above-mentioned piping, the aqueous phase was discharged in a once-through way, while the organic phase was circulated in the apparatus. After the entire treatment of the aqueous phase (aqueous nitric acid solution containing fine aluminum oxide powder), the fine aluminum oxide powder adhering to the vessel walls in the apparatus was removed using a piston.
[0079] The above experiment was repeated twice a week for three months. The nozzle was never washed in the meantime, but the performance of the nozzle did not deteriorate, the clogging did not occur, and the nozzle could be used stably. After the nozzle durability test for three months was completed, the nozzle was weighed, and the mass of the nozzle was compared before and after use. As a result, no change in mass was observed.
[0080] As described above, as a result of conducting a long-term experiment using fine particles of aluminum oxide having a particle diameter of 0.045 mm or less and using a nozzle having an inner diameter of a capillary tube of 0.2 mm, the accumulation of fine aluminum oxide particles did not occur in the nozzle. It is known that solid components with a larger particle size are more likely to accumulate in the nozzle. In this embodiment, the inner diameter of the capillary tube of 0.2 mm was about 4.4 times the maximum particle size of 0.045 mm. Therefore, in order to prevent the solid components from accumulating in the nozzle, the inner diameter of the capillary tube may be set to be at least 5 times the maximum particle size of the solid components with some margin. The same can be considered for the pores.
[0081] Further, the results of experiments performed using not only the nozzle shown in
[0082] In the bundled capillary tube nozzle using a spacer to keep the interval between the capillary tubes, when the spacer is separated from the fusion portion as shown in
Comparative Example 1
[0083] Comparison with Nozzle Using Glass Bead Sintered Plate
[0084] The nozzle of the present invention and the nozzle using the glass bead sintered plate were compared under the same conditions as those in Embodiment 1 except for the use of the organic phase spouting nozzle. Specifically, a nozzle using a glass bead sintered plate having an average pore diameter (pore size) of 0.2 mm was compared with the result of the nozzle of Embodiment 1 shown in
[0085] As a result, the spouting performance of the droplet gradually decreased, and a clear change appeared after three months. That is, the spouting amount of the droplets decreased, and the spouting was changed to sparse spouting due to partial blockage. After the endurance test for three months was completed, the nozzle was weighed, and the mass of the nozzle before and after use was compared. As a result, the mass increased after use.
Embodiment 2
[0086] Effects of Different Types of Organic Solvents
[0087] The effect of the difference in the type of the organic solvent will be specifically described below with reference to embodiment, but the present invention is not limited to the following embodiment.
[0088] Using the same emulsion flow apparatus as in Example 1, an experiment was conducted on the effect of the type of organic solvent onto the state of emulsion of the organic phase and the aqueous phase. Further, similarly to the first embodiment, an experiment was performed mainly using the nozzle of the present invention having the structure shown in
[0089] Pure water was used as the aqueous phase, and a pure solvent of an organic solvent was used as the organic phase. The experiment was conducted by selecting hydrocarbons (isooctane, D70, and benzene), alcohols (1-octanol), ketones (4-methyl-2-pentanone), amines (n-trioctylamine), phosphate esters (tributyl phosphate), and halogenated hydrocarbons (dichloromethane) as the organic solvent.
[0090] Table 1 shows the state of emulsion of various organic phases (pure solvents) and aqueous phases (pure water) in the emulsion flow apparatus. Table 1 collectively shows the experimental results obtained by using the nozzle shown in
TABLE-US-00001 TABLE 1 Glass sintered plate Organic phase nozzle Nozzle in FIG. 8 isooctane ○ ○ D70(Alkanes) ○ ○ benzene ○ ○ toluene ○ ○ 1-octanol × ○ 4-methyl-2- Δ ○ pentanone n-trioctylamine Δ ○ tributyl phosphate Δ ○ dichloromethane Δ ○ ○: Good emulsion overall Δ: Good emulsion partially ×: Does not reach the state of emulsion
[0091] As shown in Table 1, by using a capillary tube selected for a suitable material or surface treatment for the nozzle shown in
[0092] Depending on the type of organic solvent, it may be difficult to find a suitable capillary material, in which case surface treatment is effective. For example, it is possible to reduce the particle size of the droplets generated to about half by performing an appropriate surface treatment to increase the organic phobicity on the tip of the capillary tube.
[0093] Further, in order to investigate the influence of the difference in the types of organic solvents, the bundle thin tube nozzle shown in
[0094] In the nozzle in which the narrow tubes or pores having different total lengths are mixed, as shown in
[0095] Further, in the bundled capillary nozzle, depending on whether or not the spacer is provided, a large difference may occur in the range of the emulsion state (emulsion) and the stability of the emulsion. That is, the nozzles shown in
Comparative Example 2
[0096] Comparison with Nozzles Using a Glass Bead Sintered Plate
[0097] The nozzle of the present invention and the nozzle using the glass bead sintered plate were compared under the same conditions as those in Example 2 except for the difference of the organic phase spouting nozzle. Specifically, a nozzle using a glass bead sintered plate having an average pore diameter (pore size) of 0.1 mm was compared with the nozzle shown in
[0098] As a result, as shown in Table 1, for the nozzle using the glass bead sintered plate, a good (highly dispersible) emulsion state can be obtained as a whole in the two-liquid phase mixing part of the emulsion flow apparatus only when the organic solvents were hydrocarbons. With respect to other organic solvents, a partially good (highly dispersible) emulsion state was not able to be obtained, or even an emulsion state was not able to be obtained. That is, it did not work as a nozzle for generating an emulsion.
Embodiment 3
Effect of Total Length of Capillary Tubes or Pores on Droplet Size
[0099] A plurality of thin tubes made of fluororesin having an inner diameter of 0.5 mm, of which length is different between 0.7 to 2 mm are were prepared. Using a peristaltic pump, D70, which is one of the alkane-based solvents, was sent into water at the same flow rate, and the particle size of the generated droplets was measured. It has been found that even if the inner diameter of the capillary tube is the same and further the liquid is sent under the same condition using the same pump, the particle diameter of the generated droplet may be varied by changing the total length of the capillary tube.
[0100] Specifically, when the total length of the capillary tube (inner diameter 0.5 mm) is less than 1 mm, it is difficult for the droplet to separate from the tip portion of the capillary tube, and the droplet stays at the tip portion for a long time and grows greatly. This phenomenon is considered to be caused by the reason that the in-tube flow velocity does not reach such a speed that the liquid droplet could immediately leave the tip portion of the capillary tube by a shortage of the run-up distance of D70 passing through the capillary tube. That is, in order to prevent the droplet from staying long at the tip of the thin tube, a sufficient total length is required for the inner diameter of the thin tube. In this embodiment, the total length of the thin tube is required to be twice or more the inner diameter (the total length was 1 mm or more with respect to the inner diameter of 0.5 mm). Even if the inner diameter of the thin tube is less than 0.5 mm, it is considered that the total length of the thin tube requires more than twice the inner diameter for the same reason (insufficient approach distance, etc.). The same applies not only to thin tubes but also to pores. It was also found that the smaller the contact angle of the droplet of the organic phase with the surface of the tip portion of the capillary or the fine pore (the easier it is to wet), the larger the particle size of the droplet.
[0101] That is, it was found that the limit of the length (total length) of the capillary or the pore differs depending on the type of the solvent constituting the organic phase and the surface material of the capillary or the pore constituting the nozzle.
Embodiment 4
Effects of Pump Discharge Pressure and Contact Angle on Droplet Size
[0102] Using a fluororesin capillary tube having an inner diameter of 0.2 mm and a total length of 20 mm, by sending D70 into water with a peristaltic pump, the effects of pump discharge pressure and contact angle on the droplet size of D70 were investigated. As a result, it was found that it is preferable to set the discharge pressure of the pump as low as possible within a range where droplets are generated. If the pump discharge pressure is too high, the spouting of the liquid phase becomes jet, and it is not possible to maintain an appropriate droplet size distribution and shape. In order to generate good liquid droplets, it is necessary to set the discharge pressure of the pump in consideration of the inner diameter of the capillary tube or pore forming the nozzle, the viscosity of the liquid phase, and the like. For example, a liquid phase having a higher viscosity required a larger pump discharge pressure to obtain an appropriate droplet size distribution and shape.
[0103] It was found that the size of the contact angle (in this case, the contact angle defined by a three-phase system consisting of a solid surface and two liquid phases) between the solid surface and the liquid phase at the tip of the nozzle was a more important factor than the pump discharge pressure as an effect on the droplet size. Specifically, with respect to a fluororesin capillary tube having an inner diameter of 0.2 mm and a total length of 20 mm, the droplet diameter when D70 was spouted was compared between a hydrophilic processed (with improved organophobic and increased contact angle) and a non-hydrophilic processed. In the case of the hydrophilic processing, the droplet diameter was about half that of the non-hydrophilic processing. Similarly, when the same hydrophilically processed fluororesin tubule is used for jetting the aqueous phase, the droplet size of the aqueous phase (pure water) became about twice that of the non-hydrophilically processed type (fluororesin with unique high water repellency).
[0104] That is, when the contact angle is large (hard to wet), the “drop of the droplet” from the nozzle tip is improved as compared with the case where the contact angle is small (easy to wet). Further, the particle diameter of the droplet was closer to the inner diameter of the capillary or the pore, and a droplet having a smaller variation and a more uniform shape was generated. Namely, in order to generate droplets with a sufficiently small particle size, high water repellency (hydrophobic) was required for the aqueous phase spouting nozzle, and high oil repellency (organophobic) was required for the organic phase spouting nozzle.
[0105] The present invention provides, for example, an aqueous phase spouting nozzle and/or an organic phase spouting nozzle, which is provided for the purpose of emulsifying and mixing an aqueous phase and an organic phase, as one component forming an emulsion flow apparatus used for liquid-liquid extraction or the like. On the other hand, the nozzle of the present invention cannot be used as a nozzle in a liquid-liquid extraction apparatus (for example, a spray column) which does not like the occurrence of an emulsion state (emulsion). The parts of the present invention are not limited to the emulsion flow apparatus, and it can be used as a nozzle in all of the apparatuses and mechanisms for mixing the liquid phases to an emulsion state (emulsion) using the spouting of droplets are used for emulsion generation.
[0106] The emulsion generating nozzle of the present invention has two advantages in industrial use as compared with a conventional nozzle using a bead sintered plate.
[0107] One feature is that emulsion of an organic phase and an aqueous phase can be performed with highly polar organic solvents such as alcohols, and ketones, etc. not limited to hydrocarbons, and an emulsion can be generated. A nozzle using a conventional glass bead sintered plate works effectively for spouting droplets of hydrocarbons, but is not always effective for highly polar solvents such as alcohols and ketones. In many cases, the emulsion does not reach a stable emulsion state.
[0108] On the other hand, in the nozzle according to the present invention in which capillary tubes or pores with an appropriate length are assembled, if an appropriate material is selected, or an appropriate surface treatment is performed, a sufficiently stable emulsion can be generated even with a solvent that does not lead to an emulsion with a nozzle using the bead sintered plate. For example, it is effective for the organic solvent which cannot be dealt with by the conventional nozzle for generating an emulsion, particularly for a polar organic solvent. Therefore, such a nozzle is effective when is used as a droplet spouting part of the emulsion flow apparatus, and its industrial applicability would further expand.
[0109] The nozzle of the present invention is further characterized in that a phenomenon in which a fine solid component (particle component) gradually accumulates in the nozzle over a long period of use can be avoided. In a nozzle using a conventional bead sintered plate, the flow path structure inside the sintered plate is complicated and irregular, so that fine particle components are easily captured in the structure inside the flow path, and a part thereof remains without flowing out, the accumulation progresses, and eventually the nozzle does not function.
[0110] On the other hand, in the liquid-phase spouting nozzle of the present invention having a structure in which capillary tubes or pores having simple and regular flow paths are assembled, the accumulation of particle components is less likely to occur, compared to a bead sintered plate. In other words, over a long period of time, since it is possible to prevent the accumulation of fine particle components, compared with conventional nozzles, in that it can be used for a longer period and more stably, for example, if it is used as a component of an emulsion flow apparatus, its industrial applicability is expected to expand further.