JPS5836626A - Dispersing and mixing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dispersion mixing device in which an inlet for injected fluid is formed in the wall of a conduit for passing a main fluid. A method for mixing fluids of ζ2, or a device for mixing volumes,
A dispersion mixing device for use when the viscosity or other properties of the fluid change.

As a method of injecting and mixing a different type of fluid into the main flow, for example, a T
Synthetic flow obtained by connecting a pipe equipped with an injection port, such as a cross-section tube, a single-section tube with a nozzle, or a tube with multiple injection ports, and injecting a different type of fluid into the main flow through the injection port. It is known to mix by a subsequent line mixer.

However, when the physical properties of the main fluid and the injected fluid are significantly different, for example when steam is mixed with the main fluid such as a liquid or solid-containing liquid, and when the mixing results in a chemical change, for example, when the mixture is very viscous, When starch milk is directly mixed with steam and heated, there is a problem that a homogeneous mixed fluid cannot be obtained efficiently according to the conventional method. In general, a tapered venturi (a part of the venturi whose cross section expands toward the downstream) is formed as a conduit for the main fluid, and a large number of injection nozzles are arranged on the wall of the part of the venturi to inject high-pressure steam. However, with this method, it is difficult to stir a highly viscous main fluid due to excessive pressure drop, and fluctuations in flow rate (2) The mixing range is narrow and uniform mixing is difficult. There are problems such as generation of noise and vibration, and the need to drill a large number of injection ports in a part of the venturi.Particularly when producing glue by injecting steam into a starch dispersion, there is a significant change in viscosity ( ; Due to poor mixing, the formation of so-called joint powder and clogging of the injection port tend to occur, and the sudden increase in viscosity results in insufficient mixing and large pressure loss.

The present invention seeks to overcome these drawbacks of conventional methods. That is, in the dispersion mixing device C of the type described at the beginning of the present invention, a spiral element twisted about the tube axis is disposed in the conduit, and an inlet is disposed on the outer peripheral tube wall of the spiral element. , is characterized by a static mixer placed downstream. Further, the present invention provides a dispersion mixing device in which the conduit is formed into a tapered shape with an enlarged cross-sectional radius, and a spiral element having a tapered outer periphery is disposed inside the conduit.

The present invention will be described in detail below based on preferred embodiments.

In FIG. 1, a dispersion mixing device 1 which is an embodiment of the present invention is shown.
0 basically consists of an injection part 2 and a subsequent static mixer part 1, and the main part of the part 1゜2 is a conduit 11, and a plurality of injection ports 3 are opened in the pipe wall of the injection part 2. ,
A spiral element 4 is fitted within the conduit 11 of the injection section 2 .

The static mixer part 1 is known per se, and includes, for example, two torsion blades 12 twisted by about 180 degrees, which are fitted alternately so that their ends are perpendicular to each other and their torsion directions are opposite to each other. Formed (for example, Japanese Patent Publication No. 44-829
0, Japanese Patent Publication No. 52-17264, etc.).

The spiral element 4 inside the injection part 2 is made by twisting a piece of wood around the tube axis, and has a twist angle of at least 360 degrees, usually 360 to 720 degrees. The practical upper limit is about 3600 degrees, but this depends on the manufacturing of the torsion plate and the practical design of the injection part, and the twist angle is not necessarily limited to this upper limit.

The pipe wall of the conduit 11 of the injection part 2 (= means that the number of injection ports 3 is at least 2 or more, usually an integer multiple of 2, the spiral element 4
It is arranged so that at least one or more is distributed to each tube chamber in the conduit 11 divided by.

The actual number of injection portions 2 and their distribution are selected depending on the purpose, and are arranged at intervals in the circumferential and axial directions of the tube wall or at appropriate helical rotation angle intervals.

The installation angle of the inlet 3 with respect to the conduit 11C is preferably inclined at a predetermined angle with respect to the direction of the flow of the main fluid (: axis C = as illustrated in FIG. 1 in the axial cross section. In the cross section perpendicular to the axis The installation angle between the conduit 11 (two) of the inlet 3 may be perpendicular (radial direction) to the pipe wall (for ease of installation and effectiveness); : On the other hand, it is also possible to inject obliquely at a predetermined angle.In the present invention, the injection fluid 5 from the inlet 3 is swirled and dispersedly mixed by the helical swirling flow action of the spiral element 4, so that the injection in the cross section perpendicular to the axis is possible. The injection angle of the inlet 3 is permissible as long as it does not contradict the direction of the helical swirl flow to be formed.

The diameter and number of the injection ports 3 are determined according to the flow rate of the injection fluid 5 to be mixed, and generally the injection speed of the injection fluid 5 is higher than that of the main fluid 6.
Although it is preferable that the flow rate is substantially higher than the flow rate of , it is selected as appropriate depending on the mixing needs.

The injection conduit 13 for the injection fluid 5 leading to the injection port 3 is connected to the injection port 3.
However, from the viewpoint of simplicity of construction and ease of manufacturing, for example, as shown in FIG. It is preferable that the inlet 3 forms an extension part 3a extending in the opposite direction to the inlet 3 from the branching point with the inlet conduit 13, the tip of which is screwed in by the plug 8, To facilitate cleaning of an inlet 3 when the inlet 3 is clogged and for prevention thereof.

Usually, the conduit 11 has the same diameter as the injection part 2 and the static mixer part 1, and when a ready-made pipe is used as part of the static mixer, the conduit 11 is connected by a flange, screwing, etc. according to its attachment mechanism. Preferably the first subsequent torsion vane of static mixer part 1? 2a is opposite to the twisting direction of the spiral element 4 of the injection part 2, and more preferably, the end 4a of the spiral element 4 and the end of the twisting blade 12a intersect.

Of course, it is also possible to provide a plurality of injection ports and leave some of them unused during actual use. Furthermore, different types of injection fluids can be injected from a plurality of injection ports.

In the above embodiment, the injection part 2 is constituted by a conduit 11 having a uniform diameter, but as shown in FIG. Spiral elm with a shaped outer periphery) 4b
are fitted to form the injection part 2'a. Other conditions may be approximately the same as those in the first embodiment.

This configuration is useful for mixing fluids where the inflow and mixing of the injection fluid 5 causes a sudden property change and the viscosity rapidly increases (including cases involving reactions, etc.). That is, due to the increase in viscosity, an excessive pressure drop occurs when the diameter of the inlet port of the main flow fluid 6 is not the same as usual, and the pump pressure must be increased. can.

A specific example of this is a case where a paste is produced by injecting steam into the starch milk (suspension) described above as the main fluid. In this case, as a result of heating with steam (2), the starch becomes pregelatinized and becomes a highly viscous thickening agent. However, in the conventional mixing method, the steam is not mixed sufficiently uniformly, and cotton powder may be formed locally. However, according to the apparatus of the present invention, a uniform paste can be obtained.

The basic role of the spiral mixers 4 and 4b (mentioned above) is to swirl and mix the fluids, but in particular that they are twisted in the same direction, they are different from conventional static mixers (from the point of view of mixing efficiency). The torsion blades are assembled by reversing the direction of each twist. If the direction of twist of the torsion vanes is alternately reversed, the forced swirling force due to the flow velocity of the injection fluid 5 (steam, etc.) and the resulting injection dispersion effect will be inhibited.

For ease of manufacture, the spiral elements 4, 4b of the present invention are constructed in one piece if they are short, but if they are long, they can be divided into parts and assembled as appropriate. Naturally, it belongs to the present invention to continuously combine or assemble conventional static mixer torsion blades in the same direction of twist to form the spiral element 4. The steepness of the twist of the spiral element 4 of the present invention is expressed by the ratio between the axial length l of one twist of 180 degrees and the diameter d, where l/d = 0.7 to
1 is preferable, and the preferable range is different from l/, 3 = 1 to 3, which is generally considered to be common for conventional twisted blades for static mixers. This is because the purpose is to create a sharp swirling flow.

In the present invention, the number of inlets can be essentially reduced compared to conventional methods (in particular, it is several tenths of the number compared to the Juventeur type) due to the strong swirling mixing effect of the spiral element. Therefore, it is extremely easy to manufacture, and inspection and cleaning of the injection port (nozzle) is also easy.

As described in detail above, according to the present invention, high viscosity fluids can be mixed uniformly, and in particular, dispersive mixing of fluids whose viscosity rapidly increases due to mixing is facilitated, the configuration of the device is simplified, and the mixing operation is simplified. By reducing pressure loss, manufacturing, operation, and maintenance costs are reduced.

Further, according to the dispersion stirring device of the present invention, the length of the device to obtain the same mixing degree can be reduced compared to a conventional device in which an injection section having an injection port branch in a conduit and a known static mixer are connected. Can be shortened. This is because, in the present invention, fairly thorough mixing is already carried out in the injection section.

Hereinafter, the present invention will be explained in detail by means of operational examples.

Example 1 Heating of Fluid with Steam Using the apparatus shown in FIG. 1, starch paste at room temperature was heated with steam under the following conditions. Injection part C Nispi r
Compared to the same process using a device that does not have a coil element, the steam is evenly distributed at the injection part, which further reduces noise and vibration caused by steam condensation, and creates a fluid with a more uniform temperature. was gotten.

Heating conditions: Starch paste cold liquid 11201A1r (30° C., specific gravity 1.2°, viscosity 300 cp) was used as the main fluid, and steam (pressure 10 kVcdG) was injected at 81 kVhr. The temperature of the produced fluid is 70±3℃, the viscosity is 80~]00cp, and the pressure drop passing through the device is 0.5. It was above the axis.

Embodiment 2 Starchikutuker Apparatus of the type shown in FIG.
, taper diameter 52.7ff, spiral element twist angle 450 degrees, taper part (injection part) length 23 (
1 m, the static mixer has a diameter of 2 inches (5011
F), by arranging four 180 degree twisted blades with their ends perpendicular in the reverse twisting direction to obtain a specific gravity of ξ), starch 24
Starch milk containing starch was heated and mixed with steam to form a paste.

The starch milk was pumped at a pressure of 2.5 kVIc [1
1,000 mm, and saturated steam was pumped through the injection port (nozzle diameter 1/8 inch (30φ) x 5 pieces) at a pressure of 3'f.
dG.

Starch paste (90°C) was injected at a flow rate of 124 kVhr.
I got it. The size was uniform and did not contain cotton powder, and the increase in pressure loss due to steam heating was slight (within +1.5 kg/; -4 at pump outlet pressure). Also, the occurrence of noise and vibration was slight.

Comparative Example Figure 4 (-) Using a known venturi type device (inlet diameter 1112 inches (3811 m1), venturi throttle diameter 20'111, exit roller diameter IW inches (38 inches), nozzles 2ffφ x 300 pieces) Starch milk from the same machine as in Example 2 was pumped at a rate of 5001/hr, and Example 2
Same as (Nisteam was injected and mixed to make a paste.

With the generation of a loud noise of 70-90 (dB), the pump pressure suddenly rises to 5'l/dG, and the delivery rate is 50'l/dG.
It decreased to At. The resulting paste contained a considerable amount of cotton powder, and it was impossible to homogenize it.

[Brief explanation of drawings]

FIG. 1 is an axial sectional view of one embodiment of the present invention, FIG. 2 is another embodiment, FIG. 3 is a cross section taken along the line 1-1 in FIG. 1, and FIG. 4 is a conventional steam cutter. An example is shown below. 1...Stick mixer part 2.2a...Injection part 3...Injection port 4.4
k... Spiral element 5... Main fluid 6... Main fluid 7... Mixed fluid 8... Plug 11... Conduit patent applicant Noritake Co., Ltd. Representative Patent Attorney Asa Kato road

Claims (1)

[Scope of Claims] (1) In a dispersion mixing device in which a pipe wall f of a pipe for passing a main fluid and an inlet for injection fluid is formed, a spiral element twisted about the pipe axis is installed in the pipe. The apparatus according to claim 1, having a dispersion mixing angle, characterized in that the spiral element is provided with an inlet on the outer circumferential pipe wall thereof, and a static mixer is arranged downstream thereof. (3) The device according to claim 1 or 2, wherein at least one inlet is arranged in each tube chamber in the conduit defined by the spiral element. In a dispersion mixing device in which a pipe wall of a conduit for passage (=injection port for injected fluid is formed), the pipe is formed into a tapered shape whose cross-sectional radius increases from the main fluid inlet, and the pipe axis is inserted into the tapered pipe. A dispersion mixing device characterized in that a spiral element having a twisted and tapered outer periphery is disposed at the center, an injection port is disposed on the outer peripheral tube wall of the spiral element, and a static mixer is disposed downstream of the spiral element. ( 5) The apparatus according to claim 4, wherein the spiral element has a twist angle of 360° or more. The device according to claim 4 or 5, wherein one or more of the above devices are arranged.