JP4614913B2 - Stirring method using a vertical stirrer for high viscosity non-Newtonian fluids - Google Patents

Description

The present invention relates to a stirring method using a vertical stirring apparatus for high viscosity non-Newtonian fluid that eliminates the phenomenon of liquid rolling up to a stirring shaft that penetrates the liquid surface of an untreated liquid in a stirring tank and extends upward.

  As a vertical stirrer that stirs and mixes the liquid to be treated in a cylindrical tank, the stirring shaft protrudes upward from the tank and is connected to a rotary drive device installed outside the tank. (For example, Japanese Patent No. 2704488) and a lower drive type (for example, Japanese Utility Model Publication No. 46-34623) in which a stirring shaft protrudes from the lower part of the tank to the outside of the lower tank and is connected to a rotary driving device installed below the tank. Public notice).

  FIG. 4 shows an example of a vertical drive type vertical stirring apparatus. The stirring shaft 2 is provided so as to protrude to the upper part of the tank on the longitudinal center line of the cylindrical stirring tank 1, and the lower part of the shaft is located in the stirring tank 1. Thus, the stirring blade 5 is fixed to the outer periphery of the stirring shaft 2 in the tank 1 through the liquid surface 3 a of the liquid 3 to be treated and extending downward. A rotation drive motor 8 and a speed reducer 9 are mounted on the lid 6 at the upper part of the tank via a mount 7, and the stirring shaft 2 protruding to the upper part of the tank and the output shaft of the speed reducer 9 are connected. The stirring shaft 2 is pivotally supported by a bearing 10 held on a gantry 7, and a shaft seal device 11 for sealing the inside of the tank and the inside of the gantry 7 is provided between the outer periphery of the stirring shaft 2 in the gantry 7 and the top of the tank. ing. The agitating blade 5 is rotated in the liquid to be treated 3 via the agitation shaft 2 by the rotation drive motor 8, and the liquid to be treated 3 in the tank is agitated.

  FIG. 5 is a schematic view of a vertical drive type vertical stirring apparatus. Contrary to the upper drive type stirring device, the stirring shaft 2 arranged in the tank protrudes from the bottom of the tank on the vertical center line of the stirring tank 1 to the outside of the tank, and the stirring shaft 2 in the liquid in the tank. The agitating blade 5 is fixed to the upper end portion or the middle portion. A reduction gear 9 and a rotary drive motor 8 are provided at a lower portion of the tank 1 through a machine frame 12, and a lower end of the stirring shaft 2 extends into the machine frame 12 and is supported by a bearing 10 mounted on the machine frame 12. And connected to the output shaft of the speed reducer 9. A shaft seal device 11 is provided between the stirring shaft 2 and the tank bottom in the machine frame 12. A discharge port 4 having an opening / closing valve is provided at a position that is laterally shifted from the center of the bottom of the stirring tank 1. In the case of this lower drive type, the stirring shaft 2 does not penetrate the liquid surface 3a of the liquid 3 to be treated in the tank, and the stirring blade 5 is rotated via the stirring shaft 2 by the rotation drive motor 8 being driven. The liquid 3 to be treated in the tank is stirred.

  In the upper drive type stirring device in which the stirring shaft protrudes above the stirring tank, when the liquid having high viscosity and non-Newtonian property is stirred, due to the Weisenberg effect, the stirring shaft 2 is rotated as shown in FIG. In other words, the liquid 3 is clung to the shaft 2 at the portion where the stirring shaft 2 penetrates the liquid surface 3a in the tank (indicated by reference numeral 13), and good stirring and mixing operations may not be possible. . In addition, since sufficient agitation is not performed, the liquid 3 to be treated adheres to and solidifies around the agitation shaft 2 and the agitation blade 5 or the inner wall of the tank 1, resulting in a further decrease in the agitation performance.

  Such a phenomenon is the same also in a so-called eccentric shaft type stirrer in which the stirring shaft is shifted from the center of the tank to the side, and the stirring shaft 2 is shifted from the center of the tank 1 as shown in FIG. However, it rotates around the axis of the shaft 2, and the liquid 3 roll-up portion 13 is generated at the portion where the stirring shaft 2 protrudes from the liquid level 3 a in the tank (the liquid surface penetrating portion of the shaft). In order to eliminate this phenomenon of rolling-up, when the phenomenon of rolling-up of the liquid is visually recognized during operation, the operation is performed by reducing the rotation speed of the stirring shaft 2 or lowering the liquid viscosity (decreasing non-Newtonian properties). However, both of these methods result in a decrease in productivity, and the product may be altered by lowering the liquid viscosity. Furthermore, when the roll-up phenomenon appears, if the shaft rotation speed is increased to improve the mixing state in the tank, a larger roll-up may occur depending on the target liquid, and a substantially good stirring operation can be performed. Disappear.

  In the lower drive type stirring device that protrudes downward from the bottom of the tank and is connected to the rotation drive motor on the lower side of the tank, the stirring shaft is positioned below the liquid level in the tank, and there is no liquid level penetrating part. The above-described phenomenon of liquid roll-up due to the Weisenberg effect does not occur. However, the lower drive type does not have a simple sealing mechanism at the bottom penetration part of the agitation shaft, and the drive part is located at the lower part of the tank. It is necessary to devise ingenuity so that the liquid does not remain on the bottom, which is disadvantageous in that the cost is higher than that of the upper drive type and a large installation space is required. In addition, the lower drive type may not be adopted depending on the target liquid.

The present invention eliminates the above-mentioned conventional problems and can reduce the rolling-up of the liquid to the stirring shaft even under conditions where the liquid-rolling phenomenon occurs, and even in a high-viscosity liquid, the stirring and mixing state is good and uniform. An object of the present invention is to provide a stirring method using a vertical stirring apparatus for a high viscosity non-Newtonian fluid capable of greatly reducing the mixing time.

The stirring method using the vertical stirrer for high-viscosity non-Newtonian fluid according to the present invention includes a stirring shaft inserted into the tank from above the stirring tank, and stirred via the stirring shaft by a driving source outside the tank. In a stirring method using a high-viscosity non-Newtonian fluid vertical stirrer that rotates a blade to stir the liquid to be treated in the tank, the high-viscosity non-Newtonian fluid vertical stirrer A shaft and the stirring blade are connected by a side shaft portion displaced laterally from the axis of the stirring shaft, and the stirring blade includes an upper cross member fixed to a lower end of the side shaft portion; , a vertical member of the plurality of coupled upper end to the upper cross member is secured to the lower end of the respective longitudinal member, than said upper horizontal member and a width wide Do paddle, to prevent the Weissenberg effect, the the lower end of the stirring shaft connected to a drive source and at a position above the liquid level in the tank the攪As the upper end of the blades to a lower position than the liquid level in the tank, characterized in that the liquid level is set.

  According to the present invention, the phenomenon of liquid roll-up on the stirring shaft, which is a problem when stirring non-Newtonian fluids and high-viscosity liquids, is eliminated, and the number of rotations can be arbitrarily increased. A sufficiently strong stirring operation is possible, and stirring performance such as good stirring and shortening of uniform mixing time can be improved. Further, since there is no liquid level penetrating shaft that rotates in the liquid level portion, the liquid in the tank does not adhere to and adhere to the stirring shaft. Further, the present invention has many effects such as not only preventing the Weisenberg action of a non-Newtonian fluid but also solving problems such as adhesion and sticking of slurry to the shaft portion in a high concentration slurry system.

  Next, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a vertical stirring apparatus for high viscosity non-Newtonian fluid according to one embodiment of the present invention. A rotary drive motor 8 and a speed reducer 9 are mounted on the upper part of the cylindrical stirring tank 1 via a gantry 7, and the agitation shaft connected to the output shaft of the speed reducer 9 is supported by a bearing 10 in the gantry 7. The portion extending into the stirring tank 1 through the shaft seal device 11 is the same as the conventional example shown in FIG. In the present invention, the stirring shaft extending from the upper part of the stirring tank 1 into the tank is not immersed in the liquid 3 to be treated, and the lower end of the shaft is positioned above the liquid surface 3a of the liquid 3. Here, the upper stirring shaft 16 is referred to. A lower stirring shaft 17 is disposed near the lower portion in the stirring tank 1 and extends upward while supporting the stirring blade 5. A lower shaft 17 below the liquid surface 3 a of the liquid 3 to be treated in the tank is a side shaft described later. It is connected to the lower end of the upper stirring shaft 16 by a part (indicated by reference numeral 19 as a whole). That is, the upper end of the lower stirring shaft 17 is positioned below the liquid level 3a, and the liquid level penetrating portion of the shaft member that connects the stirring blade 5 in the liquid 3 to be treated and the rotary drive motor 8 outside the tank is Only the side shaft portion 19 is provided.

  The upper and lower stirring shafts 16 and 17 are arranged on the same axis, but the side shaft portion 19 is shifted laterally from the central axis of these upper and lower stirring shafts 16 and 17. In the embodiment of FIG. 1R> 1, the side shaft portion 19 includes a pair of upper and lower side shafts 20 and 25 and a pair of upper and lower horizontal shafts connecting the shaft ends of the side shafts 20 and 25 to the upper and lower stirring shafts 16 and 17, respectively. The shaft 21 is configured. The axis lines of the side shafts 20 and 25 are shifted laterally by a radius R with respect to the axis lines of the upper and lower stirring shafts 16 and 17 (vertical center line of the tank).

  During the stirring operation, the liquid level 3a of the liquid 3 to be treated moves up and down to some extent in the tank, but the lengths of the side shafts 20 and 25 are set to cover the expected liquid level fluctuation. When the upper stirring shaft 16 is rotated by driving the rotary drive motor 8, the pair of side shafts 20 and 25 rotate around the axis of the upper stirring shaft 16 and on a circle having a radius R from the axis of the stirring shaft 16. The stirring blade 5 and the lower stirring shaft 17 in the liquid rotate around the axis of the upper stirring shaft 16, and the liquid 3 to be treated is stirred and mixed by the stirring blade 5. Since there is no shaft member that rotates around the axis in the vicinity of the liquid surface 3a of the liquid 3 to be treated, the liquid 3 does not roll up along the side shafts 20 and 25 even if it is a high-viscosity liquid. Stirring and mixing can be obtained, and problems such as adhesion and sticking of the liquid 3 to the side shafts 20 and 25 near the liquid surface can be solved.

  The side shaft portion 19 according to the present invention is not limited to the form in which the pair of side shafts 20 and 25 are arranged opposite to the position in the diameter direction of the agitation tank 1 as in the above-described embodiment. The side shafts of 3 or 4 or more, or in some cases up to about 8 in some cases, are arranged around the axis of the agitation shaft 16, and the upper end and the lower end of the side shaft are respectively set to appropriate horizontal axes. The upper stirring shaft 16 and the lower stirring shaft 17 may be connected to each other. FIG. 2 is a schematic view showing another embodiment of the present invention in which the upper and lower stirring shafts 16 and 17 are connected by a single side shaft 20 in the vicinity of the liquid surface. In this case, the side shaft portion 19 has one side shaft 20 that is shifted laterally from the axis of the upper and lower stirring shafts 16, 17, and the upper side that connects the upper end of the side shaft 20 to the upper stirring shaft 16. The shaft 22 is composed of a lower horizontal shaft 23 that connects the lower end of the side shaft 20 to the lower stirring shaft 17. The side shaft 20 has a length that covers the liquid level fluctuation and penetrates the liquid level 3a.

  In any of the above-described embodiments, the one-stage paddle-shaped stirring blade 5 is attached to the lower end of the lower stirring shaft 17, but the stirring blade is not limited to the paddle in the present invention. Further, the stirring blade may be directly fixed to the lower portion of the side shaft portion without connecting the stirring blade and the side shaft portion with the lower stirring shaft. FIG. 3 is a side sectional view showing another embodiment of the present invention in which a stirring blade is directly attached under the side shaft portion. In this embodiment, a large joint blade called Max Blend (registered trademark of Sumitomo Heavy Industries, Ltd.) is used as a stirring blade. The structure of the bearing 10 supporting the upper stirring shaft 16 protruding into the gantry 7, the shaft seal device 11, the speed reducer 9 mounted on the gantry 7 and the rotary drive motor 8 is the same as in the case of FIGS. 1 and 2. It is. A pair of side shafts 20 and 25 are connected to the lower end of the upper stirring shaft 16 located above the liquid surface 3 a of the liquid 3 to be treated via the upper horizontal shaft 26. As described in the embodiment of FIG. 1, the two side shafts 20 and 25 are arranged by being shifted by the same distance from the shaft end of the upper stirring shaft 16 to the side. An upper end of a large joint blade described later, that is, an upper cross member 27 of the lattice blade 30 is fixed. The lattice blade 30 includes a plurality of vertical members 29 and an upper horizontal member 27 that connects the upper ends of these vertical members 29.

  Further, a wide paddle 31 is fixed to the lower end of the lattice blade 30 (the lower end of each vertical member 29). Here, the wing in which the paddle 31 is fixed to the lattice wing 30 is referred to as a large coupled wing. In some cases, a cross member that connects the middle part of the vertical member 29 may be provided in the lattice blade 30 as necessary. The longitudinal center line of the large coupling blade coincides with the axis of the upper stirring shaft 16, the upper end of the coupling blade is located below the liquid surface 3a of the liquid 3 to be treated, and the lengths of the side shafts 20 and 25 are liquid. The length is set to cover the surface variation. The large coupling blade is agitated and rotated in the liquid to be treated through the upper agitation shaft 16 and the side shafts 20 and 25 by the rotation drive motor 8. Since the side shafts 20 and 25 rotate around the axis line of the upper stirring shaft 16, the liquid 3 along the side shafts 20 and 25 does not roll up even with a high-viscosity liquid. A mixed state is obtained, and problems such as adhesion and sticking of the liquid 3 to the side shafts 20 and 25 in the vicinity of the liquid surface are also solved.

  1 and 2 exemplify a flat paddle as an agitating blade. However, the present invention is not limited to the blade shape, and an inclined paddle, a large wide blade, a lattice blade, a combination of a paddle and a lattice blade in FIG. Various agitating blades such as a combined blade, a turbine blade, a swept blade, an anchor blade, and a screw blade can be employed. There are no restrictions on the number of blades or the number of stages of these blades. In addition, the axial cross-sectional shape of the side shaft portion is not limited to a perfect circle shape, and may be an elliptical axis or a 3-4 angular axis.

1 is a schematic view of a high-viscosity non-Newtonian vertical stirring apparatus according to an embodiment of the present invention. It is the schematic which shows other embodiment of this invention. It is side part sectional drawing which shows other embodiment of this invention which attached the stirring blade directly under the side axial part. It is the schematic of the conventional vertical stirring apparatus of an upper drive type. It is the schematic of the conventional vertical stirring apparatus of a lower drive type. It is a schematic perspective view which shows the winding-up state of a liquid with the eccentric shaft type stirrer which the stirrer axis | shaft shifted | deviated from the tank center to the side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Stirrer tank, 2 ... Stirring shaft, 3 ... Liquid to be treated, 3a ... Liquid level, 5 ... Stirring blade, 8 ... Rotation drive motor, 13 ... Roll-up part of liquid, 16 ... Upper stirring shaft, 17 ... Lower stirring Axis, 19 ... side axis, 20 ... side axis, 25 ... side axis, 30 ... lattice blade, 31 ... paddle

Claims (2)

A high-viscosity non-Newtonian fluid in which a stirring shaft is inserted into the tank from above the stirring tank, and the liquid to be treated in the tank is stirred by rotating the stirring blade through the stirring shaft by a driving source outside the tank. In a stirring method using a vertical stirrer,
The high-viscosity non-Newtonian vertical stirring apparatus is configured such that the stirring shaft and the stirring blade are connected by a side shaft portion whose position is shifted laterally from the axis of the stirring shaft.
The stirring blade is fixed to the upper cross member fixed to the lower end of the side shaft portion, a plurality of vertical members connected at the upper end to the upper cross member, and the lower ends of the vertical members. With paddles wider than the material,
In order to prevent Weissenberg effect, as the upper end of and the stirring blade at a position above the liquid surface of the lower end in the tank of the stirring shaft connected to the drive source becomes lower position than the liquid level in the tank, the liquid stirring method using a high viscosity and non-Newtonian fluid vertical stirring device, characterized in Rukoto surface has been set. The stirring method using the vertical stirrer for high-viscosity non-Newtonian fluid according to claim 1, wherein a vertical center line of the stirring blade coincides with an axis of the stirring shaft .

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