JPH04247248A - Method and device for continuous crushing and dispersing of solids in liquid - Google Patents

Abstract

PURPOSE: To improve, in the case of grinding and dispersing continuously a solid in a liquid using an auxiliary abrasive element, a separation of an auxiliary abrasive element from solid-liquid mixtures in the location in which a comeback region and a runoff region in the flow chamber are connected to an abrasive region. CONSTITUTION: Two walls on the location in which at least the comeback region 2 and the runoff region 3 in the flow chamber are connected to the abrasion region 1 are permitted to rotate at the same directions but different speeds.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a continuous grinding and dispersion method of a solid in a liquid as described in the first part of claim 1, and a method of continuous pulverization and dispersion of a solid in a liquid as described in the first part of claim 5. The present invention relates to commercial grinding and dispersion equipment.

0002

BACKGROUND OF THE INVENTION German Patent No. 1 223 236 describes a stirred flour mill in which, in addition to the stirrer consisting of a stirrer plate, an outer abrasive trough also rotates. However, in that device, the entire polishing element within the polishing trough is rotated by centrifugal force against the rotating outer wall of the polishing trough, and has little movement in either the radial or axial direction. Therefore, the abrasive effectiveness is considerably lower than in devices where the entire abrasive element moves and circulates.

A device within the preamble of claim 5 is known from DE-A-37 16 295. The device has a narrow slit-shaped abrasive zone through which a solid-liquid mixture and auxiliary abrasive elements flow from the inlet side to the outlet side of the abrasive zone. Then, a return area (passage) is provided in which the auxiliary polishing element is returned from the outlet side to the inlet side of the polishing zone by the action of centrifugal force, and most of the solid-liquid mixture flows out against the action of centrifugal force. It is drawn out after passing through the area.

In this known device, a flow chamber consisting of the entire polishing zone and outflow zone is surrounded by a fixed outer wall and a rotating inner wall. In the part where the return and outlet areas of this flow chamber connect with the polishing zone, the auxiliary polishing elements are separated from the solid-liquid mixture by the action of centrifugal force and are returned via the return zone to the inlet side of the polishing zone. There is. Depending on the prevailing conditions, a portion of the auxiliary abrasive element is conveyed to the outflow zone together with the solid-liquid mixture.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method according to the first part of claim 1 and a device included in the preamble of claim 5, in which the return region and the outlet region of the flow chamber are connected to the polishing region. The objective is to improve the separation of the auxiliary abrasive element from the solid-liquid mixture in the area where it is applied.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above problem by rotating the two walls of the flow chamber at least in the part where the return zone and the outlet zone connect with the polishing zone in the same direction but at different speeds. Achieved by

[0007]

Effect: The centrifugal force is then increased, especially in that part of the flow chamber, and the separation of the auxiliary abrasive elements from the solid-liquid mixture is considerably improved. That is, depending on the prevailing conditions, either none of the auxiliary abrasive elements go to the outflow zone, or only a very small portion of the circulating auxiliary abrasive elements go to the outflow zone. It is therefore possible, if desired, to dispense with mechanical screening devices such as screens altogether, which simplifies the design and maintenance of the device and allows for increased output due to reduced pressure losses.

[0008] Due to the increased centrifugal force in the polishing zone, the polishing effect is also significantly enhanced.

[0009]

[Embodiments] Hereinafter, embodiments of the present invention will be explained in detail with reference to the drawings. Preferred specific configurations thereof are also described in the dependent claims as the gist of the invention.

FIG. 1 is a cross-sectional view showing the entire first embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of the main parts thereof. 1 and 2, a first embodiment of an apparatus for continuously comminution and dispersion of solids in a liquid using an auxiliary abrasive element 18 will be described. The device contains an elongated slit-shaped abrasive zone 1 through which the solid-liquid mixture and the auxiliary abrasive elements flow from the inlet side 1a to the outlet side 1b of the abrasive zone. Further, a return zone 2 is provided in which the auxiliary polishing elements 18 are returned from the outlet side 1b of the polishing zone 1 to the inlet side 1a by the action of centrifugal force. The return area 2 is configured as a return channel. The inlet side 1 a of the polishing zone 1 is connected to the inlet zone 3 and its outlet side 1 b to the outlet zone 4 .

The abrasive zone 1, the inlet zone 3 and the outlet zone 4 are surrounded by the inner surface of an outer rotor 5 and the outer surface of an inner rotor 6, the outer and inner rotors 5, 6 having a common axis of rotation 7.
has.

The outer and inner rotors 5, 6 are driven in the same direction of rotation but at different speeds via belt pulleys 8, 9, respectively.

The inlet region 3 is connected via a channel 10 to a supply pipe 11 whose central axis coincides with the axis of rotation 7 . Correspondingly, the outflow area 4 is connected via a channel 12 to an outflow pipe 13 which is arranged concentrically with the supply pipe 11 .

[0014] To remove the heat generated within the polishing zone 1,
A cooling area 14 having a cooling water supply pipe 14a and a cooling water discharge pipe 14b is provided around the outer rotor 5. In FIG. 1, an arrow 15 indicates the direction in which the cooling water flows.

The entire device is fixed to a frame 16 of the housing.

As shown enlarged in FIG. 2, the return channel 2 extends from an end face 6b facing the outlet side 1b of the abrasive zone 1 of the inner rotor 6 toward the inlet side 1a of the abrasive zone 1 of the inner rotor 6. It extends diagonally outward toward the end surface 6a. The angle that the feedback channel 2 makes with the rotation axis 7 is 10
The angle may be between 70° and 30° to 60°.

The inflow region 3, the polishing region 1 and the outflow region 4 connected thereto have one ring-shaped slot (narrow flow path).
Make it in the shape of. In contrast, the feedback zone consists of one or more feedback channels 2.

The polishing area 1 can be divided into the following four parts. a) a first portion 1c, b extending diagonally outward from the inlet side of the polishing zone 1 substantially on the extension line of the return channel 2;
) a second portion 1d that contacts the first portion 1c at an acute angle and extends substantially parallel to the rotation axis 7; c) a third portion 1e that extends diagonally inward substantially parallel to the first portion 1c; d) A fourth portion 1f extending diagonally inwardly at an angle of approximately 90° to the return channel 2 to the outlet side 1b of the polishing zone 1.

FIG. 5 is a sectional view of the inner rotor 6 taken along line V--V in FIG. As shown in this figure, the inner rotor 6
In this case, the surface of the third portion 1e of the polishing area 1 is provided with corrugated folds.

FIG. 6 is a sectional view of the outer rotor 5 taken along line VI--VI in FIG. As shown in this figure, the surface of the outer rotor 5 facing the outflow region 4 is also provided with corrugated folds.

Of course, other cross-sectional surfaces may be used within the scope of the invention, such as grooved, studded or cam-shaped surfaces. Similarly, the positions of these cross-sectional surfaces are not limited to the positions shown in FIG. 2, but may be at other positions in the polishing zone 1, inflow zone 3, and outflow zone 4.

FIG. 3 is an enlarged sectional view showing essential parts of a second embodiment of the present invention. In this figure, parts corresponding to those in FIG. 2 are given the same or similar symbols. The difference between this second embodiment and the first embodiment of FIG. 2 lies in the structure of the outer and inner rotors 5, 6 in the part of the polishing zone 1'. That is, the polishing area 1' of the second embodiment can be divided into the following four parts. a) a first portion 1'c extending diagonally outward from the inlet side 1'a of the abrasive zone 1' substantially in the extension of the return channel 2; b) tangent to said first portion 1'c at an acute angle; a second portion 1'd extending substantially parallel to the axis of rotation 7; c) a third portion 1' extending substantially perpendicular to the axis of rotation 7;
e, d) a fourth portion 1'f extending diagonally inwards approximately at right angles to the return channel 2 to the outlet side 1'b;

FIG. 4 is an enlarged sectional view showing essential parts of a third embodiment of the present invention. This third embodiment has a third portion 1″
It differs from the second embodiment of FIG. 3 only in that the structure of e extends diagonally inwards at least approximately in a circular manner.

Of course, other configurations of abrasive zones may be envisaged within the scope of the invention.

Next, the operation of the apparatus of the present invention will be explained with reference to FIGS. 1 and 2. Solid/liquid mixtures are pumped (not shown)
is introduced into the inlet area 3 via the supply pipe 11. The direction of flow of this solid/liquid mixture is indicated by a thick arrow 17. On the inlet side 1a of the polishing zone 1, the solid-liquid mixture mixes with the auxiliary polishing elements 18. This auxiliary polishing element 18 functions to continuously finely grind and disperse solids in the liquid up to the outlet side 1b of the polishing zone 1. The auxiliary abrasive element 18 is connected to the inlet side 1 with the flow of the solid-liquid mixture.
a to the outlet side 1b and returned from the outlet side 1b of the polishing zone 1 to the inlet side 1a against the flow due to the action of centrifugal force. In contrast, most of the solid-liquid mixture is drawn out through the outflow zone 4 against the action of centrifugal force.

Compared to known structures in which the polishing area is between the stator and the rotor, in the present invention not only the inner rotor 6 but also the outer rotor 5 are driven in the same rotational direction, so that the centrifugal force is reduced. increases many times. In the known construction, for example from DE 37 16 295, the rotor has a rotor of 1500 rpm. p. m. , while the other wall of the polishing zone remains stationary as a stator. For this reason, the average rotational speed of the solid-liquid mixture containing the auxiliary polishing elements is 750 rpm. p. m. decreases to On the other hand, as in the present invention, the outer wall of the polishing area is also rotated at 3000 rpm in the same direction. p. m
．． When rotating at a speed of 2250 rpm, the average rotational speed of the solid-liquid mixture and the auxiliary abrasive elements is 2250 rpm. p. m. become. If the rotational speed increases by a factor of 3 in this way, the centrifugal force increases by a factor of 9.

As the centrifugal force increases, on the one hand the separation of the auxiliary abrasive elements from the solid-liquid mixture (in the outlet part of the abrasive zone) and on the other hand the abrasive effect in the abrasive zone is significantly improved. The increase in centrifugal force increases the polishing pressure, which improves the polishing effect. Also, since coarse solid particles generally remain in the polishing zone 1 longer than fine particles, the fine particles can be more easily removed from the stream by the weak force of gravity. Therefore, by suitably adjusting the rotational speed of both rotors, it is possible to completely eliminate oversize, ie too large, solid particles in the final product.

The rotational speed of both rotors must also be matched to the amount of auxiliary abrasive elements and the strength of the flow of the solid-liquid mixture. On the one hand, the auxiliary abrasive elements circulate in a kind of circuit consisting of the abrasive zone 1 and the return channel 2 and do not stagnate in the part of the abrasive zone that is radially farthest from the axis of rotation 7 due to too great a centrifugal force. You must do so. On the other hand, the centrifugal force, especially in the return channel 2, must be so great that the auxiliary abrasive elements are separated from the (solid-liquid) mixture against the flow of said mixture. The two rotors 5 and 6 and therefore the return zone rotating with them (return channel 2)
and the rotational speed of the wall of the flow chamber in which the outflow zone 4 connects with the polishing zone 1 is between 500 and 20,000 rpm. p. m. Especially 100
0~5000r. p. m. It is good to be. The difference in peripheral velocity of the two walls surrounding the polishing zone 1 is between 5 and 20 m/s, especially 8
It is preferable that the speed is 15 m/s.

The magnitude of the centrifugal force in the part where the return region (return channel) 2 and the outlet region 4 of the flow chamber connect with the polishing region 1 or in the whole polishing region 1 is determined by the rotation of both rotors 5, 6 on the one hand; The speed can be adjusted on the one hand by the structural radial distance of these parts from the axis of rotation 7.

By returning the flow through the return channel 2, the auxiliary abrasive elements 18 are constantly moved and a good abrasive action is achieved. This effect is further reinforced by the cross-sectional shape of the wall surrounding the polishing zone 1 and the many bends in the polishing zone 1 at acute or obtuse angles.

The diameter range of the auxiliary abrasive elements is, for example, 0.1
~0.5mm is sufficient. Even with these sizes of auxiliary abrasive elements, the forces due to gravity are large enough to achieve effective high abrasive effects. The invention also relates to German Application No. 37
A structure in which several polishing zones (each having an inflow zone, an outflow zone, and a return zone) are connected in series may be used, as in the structure shown in No. 16 295.

[0032]

[Effects of the Invention] What has been described in the [Function] section above is the effect of the present invention, and therefore, redundant description will be omitted.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the entire first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing essential parts of the first embodiment.

FIG. 3 is an enlarged sectional view showing main parts of a second embodiment of the present invention.

FIG. 4 is an enlarged sectional view showing main parts of a third embodiment of the present invention.

5 is a sectional view of the inner rotor 6 taken along line V-V in FIG. 2. FIG.

6 is a sectional view of the outer rotor 5 taken along line VI-VI in FIG. 2. FIG.

[Explanation of symbols]

Regarding the reference numerals in the drawings, since they are shown in addition to the constituent elements corresponding to the embodiments in the claims, their repeated description will be omitted.

Claims (12)

[Claims] 1. A method for continuously finely pulverizing and dispersing solids in a liquid using an auxiliary abrasive element (18), comprising:
Said abrasive element (18) passes through at least one slit-shaped abrasive zone (1, 1') on its inlet side (1a, 1'a).
together with the solid-liquid mixture (17) towards its outlet side (1b, 1'b) and then through the return area (2) under the action of centrifugal force into the abrasive area (1, 1'). from the outlet side (1b, 1'b) to the inlet side (1a, 1'b) of
'a), during which at least a large portion of said solid-liquid mixture flows into the outflow area ('a) against the action of centrifugal force.
4), at least the return area (2) and the outflow area (4) are connected to the polishing area (1, 1).
') A method for continuous comminution and dispersion of solids in a liquid, characterized in that the walls of the flow chambers connected with the flow chambers are rotated in the same direction, but at different speeds. 2. Process according to claim 1, characterized in that the walls of the polishing zone (1, 1') and the outlet zone (4) are rotated in the same direction but at different speeds. Claim 3: The above return area (2) and outflow area (4)
is the wall of the flow chamber connecting with the polishing area (1, 1').
0~20000r. p. m. 2. The method of claim 1, further comprising rotating at a speed of . 4. In the polishing area (1, 1'), the difference in peripheral speed between the two walls surrounding the polishing area is 5 to 20 m/s.
3. The method of claim 2. 5. An apparatus for continuously finely pulverizing and dispersing solids in a liquid using an auxiliary abrasive element (18), comprising:
a) a solid-liquid mixture (17) and an auxiliary abrasive element (1)
8) from the inlet side (1a, 1'a) to the outlet side (1b, 1'
b) at least one slit-shaped abrasive zone (1,1') flowing towards the abrasive zone; , 1'b) returning toward the entrance side (1a, 1'a);
c) an outflow zone (4) for discharging at least a major part of said solid-liquid mixture against the action of centrifugal force, d) at least said return zone (2) and outflow zone (4); Apparatus for continuous comminution and dispersion of solids in a liquid, characterized in that the flow chamber, which is connected to said polishing zone (1, 1'), is surrounded by two walls rotating in the same direction but at different speeds. 6. The abrasive zone (1, 1') and the outflow zone (4) are surrounded by at least a part of the inner surface of the outer rotor (5) and at least a part of the outer surface of the inner rotor (6). These outer and inner rotors share a common rotation axis (7).
6. A device according to claim 5, characterized in that it has: 7. The return area includes the inner rotor (6).
from the end face (6b) facing the outlet side (1b, 1'b) of the polishing area (1, 1') of the inner rotor (6) to the inlet side (1a) of the polishing area (1, 1') of the inner rotor (6). , 1'a), at least one return channel (2) extending diagonally outwards up to the end face (6a) facing .
7. Device according to claim 6, characterized in that the temperature is .degree. 8. Device according to claim 5, characterized in that the abrasive zone (1, 1') and the part of the outflow zone (4) connected thereto have the form of a ring-shaped slot. 9. The polishing area (1) comprises: a) the polishing area (
1) a first portion (1c) extending diagonally outward from the inlet side (1a) of the return channel (2) substantially on an extension of the return channel (2); b) touching the first portion (1c) at an acute angle; , a second portion (1d) extending substantially parallel to the rotation axis (7), and c) the first portion
a third part (1e) extending diagonally inwards substantially parallel to part (1c); and d) said return channel (
2) extending diagonally inwardly to the outlet side (1b) of said polishing zone (1).
8. Device according to claim 7, characterized in that it consists of a part (1f). 10. The abrasive zone (1') is arranged diagonally outwardly from a) an inlet side (1'a) of the abrasive zone (1') substantially in an extension of the return channel (2); b) an extending first part (1'c); and b) said first part (1'c).
c) a second portion (1'd) extending substantially parallel to the rotational axis (7) at an acute angle; and c) a third portion (1'e) extending substantially perpendicular to the rotational axis (7). ); d) a fourth portion (1'f) extending diagonally inwardly approximately at right angles to the return channel (2) to the outlet side (1'b) of the abrasive zone (1'); 8. The device of claim 7, comprising: 11. The abrasive zone (1') extends diagonally outwardly from a) an inlet side (1'a) of the abrasive zone (1') substantially on an extension of the return channel (2); b) an extending first part (1'c); and b) said first part (1'c).
c) a second part (1'd) extending substantially parallel to the rotation axis (7) at an acute angle; )
and d) a fourth portion (1'f) extending diagonally inwards substantially at right angles to the return channel (2) to the outlet side (1'b) of the abrasive zone (1'). 8. Apparatus according to claim 7, characterized in that: 12. In the part of the polishing area (1, 1') and the outlet area (4) connected thereto, the outer surface of the inner rotor (6) surrounding the polishing area and the outlet area and the outer rotor 7. The device according to claim 6, wherein at least a portion of the inner surface of (5) has grooves on the surface.