JPS58899B2 - Continuous clay slurry production equipment - Google Patents

Description

[Detailed Description of the Invention] In shield work for constructing underground structures, locally generated soil is often used as a backfill injection material.

However, the above-mentioned generated soil in particle units such as sand can be used as is as a backfilling injection material, but clay and other clay soils have extremely low unconfined compressive strength, so they can be used as is as a backfilling injection material. Therefore, it is either discarded as defective, or when used as a backfilling material, it is made into clay slurry by pulverizing it into particles and mixing it with a solidifying agent such as mortar or cement. However, it is considered extremely difficult to crush such clay into particles.

Conventional crushing equipment for the above-mentioned cohesive soil includes: (1) Clay dissolving device 2, New Gram Machine 3, Cement milk mixer 4, Grinding mixer 5, Turbine pump type free crusher, Ballmin, and Vibro type were used on a trial basis. has been reported.

Moreover, since the above 1 to 4 are batch type crushers, there are problems in terms of capacity, size, price, labor saving, automation, etc.Also, the above 5 is a continuous type, but the viscosity It was unsuitable for domestic use.

Therefore, as a result of studies in view of the above-mentioned conventional circumstances, the present invention proposes a new continuous clay slurry manufacturing device that is applied to crush locally generated clay soil in order to use it as a backfilling injection material. By appropriately forming material passages in the crushing tank and appropriately arranging crushing blades, stators, and filters in the passages, it is possible to continuously process clay slurry with an appropriate moisture content, and it is possible to process it in a small size. The purpose is to increase the unit capacity.

The drawings showing an embodiment of the present invention will be described in detail below. In FIG. 1, 1 shows a frame, 2 shows a crushing tank installed upright on the frame 1, and 3 shows an electric motor built into the frame 1. .

The crushing tank 2 has a taper in which the inner diameter gradually increases from the input port 4 at the upper end to the lower end. Each of these is equipped with a water inlet 5°5 so that the water content ratio of the slurry can be adjusted.

In addition, the water inlets 5, 5 are formed by installing a water inlet pipe 6, which is a thin film, with a large number of small holes 6a at appropriate intervals along the inner wall surface of the grinding tank 2. Inject water evenly into the interior.
The upper water inlet 5 also serves to prevent sticky soil from adhering to the wall surface.

A rotary shaft 7 is protruded from the center of the lower part of the pulverizing tank 2 and is supported by a shaft bearing (not shown) of the frame 10, and the part that projects into the pulverizing tank 2 is formed into a cone part 8. ,
A narrow passage portion 9 having an approximately V-shaped cross section and an annular planar shape is formed between the cone portion 8 and the peripheral wall surface of the crushing tank 2, and in the narrow passage portion 9, a narrow passage portion 9 protrudes from the cone portion 8 in the radial direction. A plurality of crushing blades 10 are arranged at appropriate intervals in two stages, upper and lower, and cutting blades 11 and
... are arranged, while the above-mentioned crushing blades 10...
A plurality of stators 12 are disposed between the stators 12 and the cutting blades 11, and are fixed to the inner surface of the peripheral wall of the crushing tank 2.

Further, a filter 13 is appropriately fixed to the peripheral wall of the crushing tank 2 so as to close the narrowest width at the lower end of the narrow passage section 9 from below, and a filter 13 is appropriately fixed to the peripheral wall of the crushing tank 2 at the lower side thereof. It communicates with a slurry discharge port 15 via a rake 14 disposed at the bottom.

Further, at least in the lower part of the crushing tank 2, a plurality of short cylinders 2a are coaxially connected to flanges 2'a...
Each short cylinder 2a is formed by fastening the ... with bolts 16.

The stator 12 . . . and the filter 13 are removably attached to the crushing tank 2 .

The filter 13 is available in two types, a perforated plate 13a and a mesh plate 13b, as shown in FIGS. 2A and 2B, and can be used interchangeably depending on the properties of the crushed soil and slurry specifications. .

Furthermore, an appropriate number of baffle plates 17 are removably attached to the upper inner surface of the peripheral wall 2' of the pulverizing tank 2 to prevent rotation of the pulverized soil in the pulverizing tank 2.

Further, the rotating shaft 7 has a protruding portion 7a into the crushing tank 2.
It is formed by integrally attaching a cone member 8a, which is a separate member, to the coaxial shaft 7.

In this way, the protruding portion 7a and the cone member 8a can be separated to conveniently repair, replace, etc. the crushing blades 10.

Furthermore, the filter 13 is disposed close to the lower surface of the lowermost crushing blade 10, and by providing the filter 13 in this way, the filter 13 can also have the function of a stator. If there is a problem, it can be dammed up for a period of time and destroyed between it and the crushing blades 10.

Further, the discharge port 15 has a built-in valve 15a that can change the opening surface steplessly, and by adjusting the amount of discharged slurry to a desired amount, the residence time of the crushed soil in the crushing tank 2 can be arbitrarily adjusted. However, the degree of grinding can be selected.

In FIG. 1, reference numeral 18 indicates a slurry storage chamber provided at the bottom of the crushing tank 2, 19 indicates a transmission mechanism that interlocks the motor shaft 3a and the rotating shaft 7, and 20 indicates a power changeover switch.

In the above configuration, when producing slurry using this, the crushed soil is continuously introduced into the crushing tank 2 from the input port 4 while the electric motor 3 is started and the rotating shaft 7 is driven and rotated. While charging, the desired amount of water is supplied from the water inlet 5°5.

In the illustrated example, the pulverization is performed using gravity.

The input crushed soil is first passed through the cutting blade 11...
... to roughly cut and destroy the lumps to prevent the crushed soil from clogging the upper part of the crushing tank 2, and in this way, the crushed soil crushed to an appropriate size is transferred to the rotating part, i.e. ,
It descends into the narrow passage section 9.

The crushed soil that has descended into the narrow passage section 9 is destroyed by the crushing blades 10 rotating at high speed during its descent.

At this time, the crushing blade 10... and the cutting blade 11
The stator 12 disposed in between prevents the crushed soil in the crushing tank 2 from circulating with the rotation of the crushing blades 10. The crushed soil descends in a fixed direction at a desired speed within the passage section 9, so that the destruction described above is uniformly performed.

Further, the narrow passage section 9 has the rotating shaft 7 as a cone section 8,
Since it is formed between the cone portion 8 and the inner surface of the peripheral wall 2' of the crushing tank 2, the crushed soil is destroyed at a high circumferential speed of the crushing blades 10, so that the destruction is carried out efficiently. .

The slurry created by breaking the crushed soil into particles in this way flows out into the reservoir chamber 18 through the filter 13, and the slurry in the reservoir chamber 18 is passed through the discharge port 15 by the rake 14.
It is smoothly fed out and taken out to a predetermined position.

Furthermore, by arbitrarily operating the valve 15a to adjust the amount of slurry discharged from the discharge port 15, the residence time of the crushed soil in the crushing tank 2 can be adjusted, so the degree of crushing can be selected to a desired value. .

Of course, the water content ratio of the slurry can be adjusted as desired by increasing or decreasing the amount of water injected by operating the water inlet 5.5.

Next, the measured values are shown in the attached table, which was obtained by conducting an experiment using the apparatus of the present invention under the conditions shown in Tables 1 and 2, using the perforated plate 13a and the mesh plate 13b as the filter 13, and changing the number of revolutions of the crushing blade 100.

As a result of the above pulverization experiment, the pulverized slurry production capacity was approximately 601 per minute (slurry specific gravity 1.17 to 1.27), but the maximum capacity is thought to be 801 per minute or more.

In addition, the following was clarified regarding the pulverization state (residual rate) of the pulverized slurry.

In FIGS. 3 to 7, the rotational speed of the crushing blade and the residual rate are as follows: (1) The residual rate over 2 mm at the rotational speed of 42 rpm is 16% or less (perforated plate filter), which is sufficient capacity.

(2) The residual rate over 2 mm at a rotational speed of 720.1.00 rpm is almost O.

(3) There is a pulverization branch point between the rotational speeds of 42 Orpm and 72 Orpm.

The pulverization condition due to the difference in the amount of crushed soil input is the amount of input.

30kg/mvtin (ground slurry specific gravity around 1.20) and 40kg/min (ground slurry specific gravity 1.25)
Before and after) there is almost no difference.

In addition, the residual rate due to differences in the filter 13 is as follows: (1) Comparing the perforated plate filter 13a and the mesh plate filter 13b, the residual rate is 15% and 3% at 420 rpm.
There is a difference of more than 10%.

(2) At the rotational speed of 720.1.00 rpm, the influence of the rotational speed is large, and there is almost no difference in the residual rate depending on the filter 13.

In Figure 8, the rotation speed, current value, and load factor are rotation speed 4.
Current 10°15.18 at 20,720,1100 Orp
A, and the load factor was about 40.34.23% for the rated 44A (IIKW motor).

However, the instantaneous maximum current is rotation speed 420,720° 1.00O
It was 13, 20, 25A at rpm.

In addition, the current value due to the difference in the amount of crushed soil input is the rotation speed 1.
At 00Orpm, input amount is 30kg/min and 40
kg/min, there is only a difference of about 2A.

Furthermore, as the number of rotations decreases, the difference in current values decreases.

Looking at the pulverization state (residual rate) from the above continuous clay pulverization experiment results, the official material conditions, unconfined compressive strength qu2.5t/m
2. For clay with adhesive force C2t/m2, rotation speed is 42Orp.
There is a branch point between m and 72 Orpm at which a completely pulverized state occurs.

From this, it was confirmed that sufficient pulverization could be performed at a rotational speed of about 700 rpm.

In addition, clay crushing during on-site construction in parallel with the experiment also
Approximately 3.5 t/m2 of clay was confirmed to be sufficiently pulverized, although the cutting depth was somewhat poor.

In addition, regarding the pulverization state (residual rate) due to differences in the filters 13, the mesh plate filter 13b is better than the perforated plate filter 13a at a rotation speed of 42 rpm, but
There is almost no difference above Orpm. Considering the filter life due to wear etc., it seems that the perforated plate filter 13a is better.

In the above experimental device, an electric motor (11KW) was used with a margin, but the electric load factor was about 35% (rotation speed 72Or).
pm), it seems that a 5KW electric motor is sufficient for the output cuff.

As explained above, in the slurry manufacturing apparatus of the present invention, the crushing tank 2 having the input port 4 at the upper end and the slurry discharge port 15 at the lower end has a tapered shape in which the inner circumference of the portion from near the upper end to near the lower end expands downward. shape, and the crushing tank 2
The tapered inner surface of is provided with a baffle plate 17 in the vertical direction, and a cone portion 8 is provided at the inner end of the rotary shaft 7 that protrudes upward from the center of the bottom surface of the crushing tank 2. A narrow passage part 9 is formed between the inner wall surface of the lower side of the crushing tank 2 surrounding this, and a cone part 8 is formed in the passage part 9.
The crushing blades 10 and the stator 12 which respectively protrude in the radial direction from the inner wall surface of the crushing tank 2 are disposed so as to be displaced from each other, and a filter 13 is connected to the slurry discharge port 15 at the narrowest part of the lower end of the narrow passage section 9. A cutting blade 11 is disposed at the top of the cone portion 8, and a lowest crushing blade 10 is disposed at the bottom of the cone portion 8 in close proximity to the top of the filter.
A water inlet 5 is provided on the inner peripheral surface of the tapered upper end of the grinding tank 2,
Furthermore, the crushing layer 2 corresponding to the vertically intermediate portion of the cone portion 8
Since the water inlet 5 is also provided on the inner wall surface of the lower part, according to the device, the crushing blades 10... Because it can efficiently break down clay soil into particles at high circumferential speeds, and can process slurry continuously,
The unit capacity can be increased while making the device compact. Therefore, shield backfilling work can be carried out efficiently and economically by processing locally generated clay soil into clay slurry using an on-site method. There are advantages that can be achieved.

In particular, in the case of the present invention, the inner periphery of the predetermined portion of the crushing tank 2 is tapered to expand downward, so that the clay soil poured into the tank is easily spread, and in this state, water cannot be injected from the upper water inlet. The dispersion of the particles is promoted, and since there is also a cutting action by the vertical baffle plate 17 on the inner periphery of the tapered portion, the synergistic effect of these three causes the primary grinding to be quite advanced.

Of course, at this time, since the inner wall of the crushing tank 2 is tapered and there is also the baffle plate 17, the clay soil will not adhere to the inner wall.

Therefore, the clay soil after the above-mentioned primary crushing is applied to the cutting blade 1.
1, and then subjected to subsequent pulverization and kneading by the crushing blades 10 and stator 12, the speed of turning this into a slurry is increased, and when performing the secondary pulverization at this time, the pulverization and kneading are Since water can be injected into the stator 12 etc. from the water inlet 5, the efficiency of secondary grinding is also increased by the water injection, and it is not only possible to prevent the water from flowing down and making it difficult to obtain an appropriate moisture content. It can also prevent clay from adhering to the surface.

[Brief explanation of drawings]

Fig. 1 is a new front view showing one embodiment of the continuous clay slurry production device according to the present invention, Figs. 2A and B are plan views showing modified examples of the filter in the same device, and Fig. 3 Figures 7 to 7 are graphs showing the relationship between rotational speed and residual rate based on experimental values of the same device, and Figure 8 is a graph showing the relationship between rotational speed and current value based on experimental values of the same device. It is. 2... Grinding tank, 4... Inlet, 5...
...Water inlet, 7... Rotation shaft, 8...
・Cone part, 8a... Cone member, 9...
...Narrow passage section, 10...Crushing blade, 11...
... Cutting blade, 12 ... Stator, 1
3...Filter, 15...Slurry discharge port.

Claims (1)

[Claims] 1 A grinding tank having an input port at the top end and a slurry discharge port at the bottom end has a tapered shape in which the inner periphery of the portion from near the top end to near the bottom end expands downward, and the tapered inner surface of the grinding tank expands in the vertical direction. A cone part is provided at the inner end of the rotating shaft that protrudes upward from the center of the bottom surface of the grinding tank, and a cone part is provided in the lower part of the grinding tank surrounding the cone part. A narrow passage is formed between the wall and the passage, and in the passage, crushing blades and a stator that protrude in the radial direction from the cone and the inner wall of the crushing tank are disposed so as to be displaced from each other. A filter is disposed in the narrow portion at the lower end of the passage so as to be able to communicate with the slurry discharge port, a cutting blade is provided at the top of the cone portion, and a cutting blade is provided at the bottom of the cone portion adjacent to the top of the filter. A crushing blade is installed,
A continuous clay characterized in that a water inlet is provided on the inner circumferential surface of the tapered upper end of the grinding tank, and a water inlet is also provided on the inner wall surface of the lower part of the grinding layer corresponding to the vertically intermediate part of the cone part. Slurry manufacturing equipment.