TW201637710A - Dispersion device and dispersion method - Google Patents

Abstract

Provided are a dispersion device and a dispersion method, whereby solids can be more finely dispersed. The dispersion device (10) disperses solids included in a treatment fluid, by pressurized treatment fluid passing through a nozzle (24), and is characterized by: the nozzle (24) having an almost constant flow rate throughout, along a first axis (X) orthogonal to the forward direction (F) for the treatment fluid; and the center of the nozzle (24) having a faster flow rate in the forward direction (F) and along a second axis (Y) orthogonal to the first axis (X).

Description

Dispersing device and dispersion method

The present invention relates to a dispersing device and a dispersing method.

As a device for dispersing a solid material more finely, a dispersing device which supplies shear stress to a treatment liquid containing a solid material and finely disperses the solid matter by the shear stress is known (for example, Patent Document 1). In the dispersing device of Patent Document 1, the slurry is supplied to the slurry by a shear pressure in a state where a pressure of 150 MPa has been applied, and the solid matter in the slurry is finely dispersed.

[Prior patent documents] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2007-224997

This dispersing device can disperse, for example, a bundle of carbon nanotubes (hereinafter referred to as "CNT" as a solid matter).

In order to supply a large shear stress to the CNT, it is effective to use a treatment liquid having a high viscosity of CNT or a nozzle having a small nozzle diameter. However, when a treatment liquid having a high viscosity or a nozzle having a small nozzle diameter is used, there is a problem that CNTs are clogged in the nozzle.

Further, it is also conceivable that the CNTs are gradually dispersed by passing the processing liquid in multiple stages through a plurality of nozzles which gradually reduce the nozzle diameter. However, since the processing liquid is passed through the nozzle in multiple stages, there is a problem that the CNT is formed into a rectangular shape.

Accordingly, it is an object of the present invention to provide a dispersing device and a dispersing method which can disperse a solid material more finely.

The dispersing device of the present invention is a dispersing device for dispersing a solid matter contained in the treating liquid by passing the pressurized treating liquid through a nozzle, wherein the nozzle system is orthogonal to a traveling direction of the processing liquid. In the first axis, the overall flow velocity of the nozzle is substantially constant, and the flow velocity in the center of the nozzle is faster in the second axis orthogonal to the traveling direction and the first axis.

The dispersing method of the present invention comprises a step of passing a pressurized treatment liquid through a nozzle, and a method of dispersing a solid matter contained in the treatment liquid, characterized in that the treatment liquid is passed through a nozzle, and the nozzle is attached thereto The first axis orthogonal to the traveling direction of the processing liquid is substantially fixed at the entire flow velocity of the nozzle, and the flow velocity at the center of the nozzle is faster in the second axis orthogonal to the traveling direction and the first axis.

According to the present invention, the processing liquid is supplied in the vicinity of the surface parallel to the plane including the first axis and the traveling direction F while supplying a large shear stress to the processing liquid in the vicinity of the surface parallel to the plane including the second axis and the traveling direction. The shear stress to be applied becomes small, whereby the treatment liquid is smoothly passed. As a result, the solid material can be more finely dispersed while preventing the solid matter contained in the treatment liquid from being clogged with the flow path as a whole of the nozzle.

10‧‧‧Dispersing device

16A~16D‧‧‧Nozzle Department

24, 30, 32, 34‧ ‧ nozzle

26, 36‧‧‧1 axis X side inner surface

28, 38‧‧‧2nd inner side of the Y-axis

D‧‧‧Distance between the inner faces of the X-axis of the 1st axis

F‧‧‧direction of travel

H‧‧‧Distance between the inner faces of the Y-axis of the 2nd axis

X‧‧‧1st axis

Y‧‧‧2nd axis

Fig. 1 is a schematic view showing the configuration of a dispersion device of the present embodiment.

Fig. 2 is a front elevational view showing the configuration of the nozzle of the embodiment.

Fig. 3 is a view showing the configuration of a nozzle of the embodiment, Fig. 3A is a transverse sectional view, and Fig. 3B is a longitudinal sectional view.

Fig. 4 is a front elevational view showing the configuration of a nozzle of the modification (1).

Fig. 5 is a front view showing the configuration of a nozzle of a modification (2).

Fig. 6 is a front elevational view showing the configuration of a nozzle of a modification (3).

Fig. 7 is a view showing a model of a nozzle used in the simulation, Fig. 7A is a front view, and Fig. 7B is a perspective view.

Fig. 8 is a distribution diagram showing simulation results of the flow velocity distribution of the embodiment, and Fig. 8A is a graph showing the results of the first embodiment, the eighth embodiment, the second embodiment, and the eighth embodiment.

Fig. 9 is a graph showing the simulation results of the flow velocity distribution of the embodiment, and Fig. 9A is the result of the X-axis and the 9-th diagram Y-axis.

Fig. 10 is a distribution diagram showing simulation results of the flow velocity distribution of the comparative example, and Fig. 10A is a result of the first comparative example and the tenth comparative example of the tenth comparative example.

Fig. 11 is a graph showing the simulation results of the flow velocity distribution of the comparative example, and Fig. 11A is a graph showing the results of the X-axis and the 11-th graph Y-axis.

Fig. 12 is a view showing a simulation result of the velocity vector of the first embodiment, and Fig. 12A is a result of the FX cross section and the Fig. 12B YF cross section.

Fig. 13 is a view showing a simulation result of a velocity vector of a comparative example, and Fig. 13A is a FX section of the first comparative example, a YF section of the first comparative example of the 13th graph, and a FX of the second comparative example of the 13th figure. Section 2, the 13th picture is the second comparison The results of the YF profile.

Fig. 14 is a distribution diagram showing simulation results of the shear rate distribution of the embodiment, and Fig. 14A is a result of the first embodiment, the 14th diagram, the second embodiment, and the 14th embodiment of the third embodiment.

Fig. 15 is a graph showing the simulation results of the shear velocity distribution of the embodiment, and Fig. 15A is the result of the X-axis and the 15th-axis Y-axis.

Fig. 16 is a distribution diagram showing simulation results of the shear rate distribution of the comparative example, and Fig. 16A is a result of the first comparative example and the 16th second drawing of the second comparative example.

Fig. 17 is a graph showing the simulation results of the shear velocity distribution of the comparative example, and Fig. 17A is the result of the X-axis and the 17th-axis Y-axis.

Fig. 18 is a view showing a result of calculating an area ratio of a high shear rate region, and Fig. 18A is a first embodiment, a 18B drawing, a second embodiment, a 18C drawing, a third embodiment, and an 18D drawing. The first comparative example and the 18Eth drawing are the results of the second comparative example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(overall)

The dispersing device 10 shown in Fig. 1 includes a compressor 12, a processing liquid supply unit 14, a nozzle unit 16A, and a cooling unit 18. The processing liquid supply unit 14 is connected to the compressor 12 via a check valve 22. The compressor 12 is connected to the power 20, and the discharge port is connected to one side of the compression pipe 21. The other side of the compression pipe 21 is connected to the inlet of the nozzle portion 16A. The outlet of the nozzle portion 16A is connected to one side of the discharge pipe 23. The other side of the discharge pipe 23 is connected to the cooling unit 18. The dispersing device 10 is configured to pass the processing liquid supplied from the processing liquid supply unit 14 through the nozzle The portion 16A is formed by dispersing a solid matter contained in the treatment liquid.

The nozzle portion 16A is formed of a cylindrical member as shown in Fig. 2, and has a nozzle 24 through which the treatment liquid passes. The nozzle 24 is formed such that the flow path is finer than the inner diameter of the compression pipe 21. The nozzle 24 is opened in parallel in the traveling direction F of the processing liquid, and is distributed in the first axis X orthogonal to the traveling direction F and the second axis Y in the traveling direction F and the first axis X. Different ways are formed. That is, the nozzle 24 is formed such that the entire flow velocity of the nozzle 24 is substantially constant in the first axis X, and the flow velocity in the center of the nozzle 24 is faster in the second axis Y. Further, for convenience of explanation, the traveling direction F is regarded as passing through the center of the nozzle 24.

In the case of this embodiment, the nozzle 24 has an elliptical shape. Thereby, the distance D between the inner surfaces of the nozzles 24 on the first axis X side is formed to be longer than the distance H between the inner surfaces on the second axis Y side. The distance D between the first axis X side inner faces 26 can be set to, for example, 50 to 300 μm, preferably 50 to 200 μm. When the distance between the inner faces 28 of the second axis Y side is regarded as H, the ratio D/H of the distance D between the inner faces of the first axis X faces can be set to 1.5 to 16, and the system 2 to 8 is preferable. 2~4 is better.

(action and effect)

Next, the operation and effects of the dispersion device 10 configured as described above will be described. First, the treatment liquid is supplied to the treatment liquid supply unit 14. The treatment liquid contains a dispersion medium and a solid matter. The treatment liquid has a viscosity of more than 1 (mPa ‧ s) from the viewpoint of obtaining a large shear stress, and more preferably more than 100 (mPa ‧ s).

The dispersion medium contains, for example, a resin and a solvent as a coating film formation. For example, the dispersion medium may be produced by using a polyimine (PI) as a resin and NMP (N-methyl-2-pyrrolidone) as a solvent. Also, the media can be dispersed It is made of polyvinylpyrrolidone (PVP) as a resin and water as a solvent. Further, the dispersion medium may be produced by using polyacrylamide (PAI) as a resin and NMP as a solvent.

For members having a solid aspect ratio of more than 10, for example, CNT or carbon nanofibers, silver nanofibers, inorganic nanofibers, cellulose nanofibers, carbon fibers, or the like can be used. Further, it is preferable to use a solid matter having an aspect ratio of more than 50. In this case, the solid state is, for example, 10 nm in diameter × 0.5 μm in length.

The compressor 12 is driven by the connected power 20 to press the processing liquid supplied from the processing liquid supply unit 14. The pressurized treatment liquid passes through the compression pipe 21 and reaches the nozzle portion 16A. The nozzle 24 is formed by making the flow path finer than the inner diameter of the compression pipe 21, and the pressure of the treatment liquid is 10 to 200 MPa immediately before the nozzle 24.

When the treatment liquid passes through the nozzle 24, it becomes a high-speed flow. Due to the passage of the nozzle 24, the treatment fluid is subjected to large shear stress. The solid matter contained in the treatment liquid is more finely dispersed due to the shear stress. In this way, a dispersion in which the solid matter is more finely dispersed is produced. The dispersion immediately after passing through the nozzle 24 is at a high temperature. The dispersion device supplies the dispersion liquid to the cooling unit 18 via the discharge pipe 23, and after the dispersion liquid is cooled to a predetermined temperature, it can be discharged.

In the case of the present embodiment, the nozzles 24 are formed in an elliptical shape, and as shown in Figs. 3A and 3B, the flow velocity distributions of the first axis X and the second axis Y are different. That is, in the first axis X, since the flow velocity is substantially constant in the entire flow velocity of the nozzle 24 (Fig. 3A), the shear rate (also referred to as the velocity gradient) of the treatment liquid in the vicinity of the first axis X is small. Thereby, the treatment liquid is in a region where the shear rate is small, that is, in the vicinity of the plane parallel to the plane including the first axis X and the traveling direction F. Shear stress small. Therefore, the solid matter contained in the treatment liquid passes through the nozzle 24 smoothly without being clogged in the vicinity of the surface parallel to the plane including the first axis X and the traveling direction F.

On the other hand, in the second axis Y, the center of the flow velocity nozzle 24 is faster (Fig. 3B). That is, the processing liquid has a large shear rate in the vicinity of the second axis Y. Thereby, the solid matter contained in the treatment liquid and the treatment liquid is large in the region where the shear rate is high (high shear rate region), that is, in the vicinity of the plane parallel to the plane including the second axis Y and the traveling direction F. Shear stress. By this shear stress, the solid system is more finely dispersed.

As described above, in the case of the present embodiment, the solid matter reaching the entrance of the nozzle 24 is more finely dispersed by being subjected to a large shear stress in the vicinity of the plane parallel to the plane including the second axis Y and the traveling direction F. . The solid material can smoothly pass through the nozzle 24 by receiving a large shear stress, even if the flow path of the nozzle 24 is blocked, and the direction is changed to be parallel to the first axis X.

In this manner, the nozzle 24 is parallel to the plane including the first axis X and the traveling direction F because a large shear stress is applied to the processing liquid in the vicinity of the surface parallel to the plane including the second axis Y and the traveling direction F. In the vicinity of the surface, the shear stress applied to the treatment liquid is small, so that the treatment liquid passes smoothly.

Therefore, the dispersing device 10 serves as the entire nozzle 24, and prevents the solid matter contained in the treatment liquid from being clogged with the flow path, and the solid matter is more finely dispersed.

(Modification)

The present invention is not limited to the embodiment, and can be appropriately changed within the scope of the gist of the invention.

For example, in the case of this embodiment, it is explained that the nozzle 24 has In the case of an ellipse, the present invention is not limited thereto, and may be a hexagonal nozzle 30 having a long lateral length in a direction parallel to the first axis X (Fig. 4), or a laterally long quadrangular nozzle 32 ( Figure 5). The nozzle portions 16B and 16C shown in Figs. 4 and 5 are substantially constant in the flow velocity of the nozzles 30 and 32 on the first axis X, and the nozzles 30 and 32 in the second axis Y. Since the flow velocity in the center is formed in a faster manner, the same effects as in the embodiment can be obtained.

Further, as shown in Fig. 6, a circular nozzle 34 can also be used. In this case, the nozzle is formed such that the frictional force between the inner surface 36 of the first axis X and the treatment liquid is smaller than the inner surface 38 of the second axis Y side. For example, the nozzle 34 may hold the first axis X side inner surface 36 at a higher temperature than the second axis Y side inner surface 38. Further, the nozzle 34 may be formed such that the roughness of the first axis X side inner surface 36 is smaller than the second axis Y side inner surface 38. Further, the nozzle 34 may be formed such that the first axis X side inner surface 36 has non-affinity with respect to the treatment liquid.

By including the nozzle 34 formed in this manner, since the nozzle portion 16D is substantially fixed at the entire flow rate of the nozzle 34 at the first axis X, the flow velocity in the center of the nozzle 34 becomes faster in the second axis Y. The method is formed, so that the same effects as in the embodiment can be obtained.

(simulation)

The flow of the fluid in the nozzle is obtained by simulation. The Reynolds number (Re) system can be obtained by the following mathematical formula (1).

Re=(ρ‧u‧D)/μ...(1)

Wherein ρ: density (kg/m ³ ), u: average flow rate (m/s), D: round tube diameter (mm), μ: viscosity (Pa ‧ s). At Re < 2000, the flow of the fluid can be considered as a laminar flow.

Here, the average flow velocity u is obtained by adding the m: weight flow rate (kg/s) and A: cross-sectional area (m ² ), and can be obtained by the following mathematical formula (2).

u=m/(ρA)...(2)

The flow velocity u(r) of the position r in the radial direction of the fluid flowing through the circular tube of the radius R can be obtained by the following mathematical expression (3).

u(r)=2u{1-(r/R) ² }...(3)

The shear rate γ(r) at the position r in the radial direction can be obtained by the following mathematical expression (4).

γ(r)=| du/dr |=4ur/R ² (4)

Further, the shear stress τ has a relationship of τ = μ ‧ (du / dr) = μ γ (r).

(model)

The flow system is regarded as a non-compressed Newtonian fluid, and it is assumed that NMP (N-methyl-2-pyrrolidone) contains 8.5 wt% of PI (polyimine) (density ρ: 1052 kg/m ³ ), viscosity μ : 0.26Pa‧s), for calculation. The nozzle shape is as shown in Figs. 7A and B, and a nozzle having an elliptical front shape is used. The size of each part is shown in the first table. As a comparative example, two types of nozzles having a true circular shape and different diameters were calculated.

(Calculation results)

Figs. 8A to C and Figs. 9A and B show simulation results of the flow velocity distribution of the nozzles of the first to third embodiments. In the 9A and B drawings, the vertical axis represents the flow rate reaching rate (%) in the case where the maximum flow velocity is 100, and the horizontal axis represents the position in the X-axis or Y-axis direction. 10A, B and 11A and B are simulation results of the first and second comparative examples. From the figure, it was confirmed that the nozzles of the first to third embodiments have different flow velocity distributions on the X-axis and the Y-axis, and have a fixed velocity in the X-axis. On the other hand, the nozzles of the first and second comparative examples have the same flow velocity distribution on the X-axis and the Y-axis.

Fig. 12A and Fig. B show the velocity vector of the nozzle of the first embodiment from the nozzle inlet to 0.5 mm. The 13A to D drawings are the velocity vectors of the first and second comparative examples.

Figs. 14A to C and 15A and B show simulation results of the shear rate distribution of the nozzles of the first to third embodiments. In the 15th and 24th drawings, the vertical axis represents the shear rate (1/s), and the horizontal axis represents the position in the X-axis or Y-axis direction. Figs. 16A and B and Figs. 17A and B are simulation results of the first and second comparative examples. From the figure, it was confirmed that the nozzle systems of the first to third embodiments differ in the distribution state of the shear velocity between the X-axis and the Y-axis, and have a region where the shear velocity is fixed on the X-axis. On the other hand, the nozzles of the first and second comparative examples have the same distribution of shear rates on the X-axis and the Y-axis.

The area ratio of the high shear rate region is shown in Table 2. Further, in Figs. 18A to 18E, the high shear rate region when the shear rate is 1 × 10 ⁷ (1/s) is shown. From the figure, the nozzles of the first to third embodiments have a wide area of the high shear rate (black portion in Fig. 18), and further, a region where the shear rate is small (the white portion in Fig. 18) is also formed. Since it is wide, it can be said that the solid matter contained in the treatment liquid can be more finely dispersed while preventing the solid matter contained in the treatment liquid from being clogged in the flow path.

On the other hand, in the first comparative example, since the inner diameter of the nozzle is large, since the area of the high shear rate region is narrow and is almost occupied by the region where the shear rate is small, it can be said that it is difficult to efficiently disperse the solid matter. Further, in the second comparative example, although the area of the high shear rate region is wide, since the region where the shear rate is small is narrow, it can be said that the solid matter is easily clogged in the flow path.

16A‧‧‧Nozzle Department

24‧‧‧Nozzles

26‧‧‧1st X-side inner surface

28‧‧‧2nd inner side of the Y-axis

X‧‧‧1st axis

Y‧‧‧2nd axis

F‧‧‧direction of travel

D‧‧‧Distance between the inner faces of the X-axis of the 1st axis

H‧‧‧Distance between the inner faces of the Y-axis of the 2nd axis

Claims (6)

A dispersing device that disperses a solid matter contained in the treatment liquid by passing the pressurized treatment liquid through a nozzle, wherein the nozzle system is in a first axis orthogonal to a traveling direction of the treatment liquid, The overall flow velocity of the nozzle is substantially constant; the flow velocity at the center of the nozzle is faster in the second axis orthogonal to the direction of travel and the first axis. The dispersing device according to claim 1, wherein the nozzle has a distance between the inner surfaces of the first shaft side being longer than a distance between the inner surfaces of the second shaft side. The dispersing device according to claim 1, wherein the nozzle holds the first axial side inner surface at a higher temperature than the inner surface of the second axial side. The dispersing device according to claim 1, wherein the nozzle has a roughness on an inner surface of the first shaft side that is smaller than an inner surface of the second shaft side. The dispersing device of claim 1, wherein the nozzle has a non-affinity in the first axial side facing the treatment liquid. A dispersion method comprising the step of passing a pressurized treatment liquid through a nozzle, and dispersing a solid matter contained in the treatment liquid, characterized in that the treatment liquid is passed through a nozzle, and the nozzle is in a traveling direction with the treatment liquid In the first axis orthogonal to the first axis, the overall flow velocity of the nozzle is substantially constant, and the flow velocity in the center of the nozzle is faster in the second axis orthogonal to the traveling direction and the first axis.