JPH0729842B2 - Rapid drying equipment for clay compacts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a clay molded body obtained by continuously extruding a raw material containing clay as a main component in a predetermined shape into a microwave heating machine at an extrusion speed and smoothly. A rapid drying device for clay compacts that can be fed to the next process without excessively reducing the water content by 5-10% in the first drying in a short time of about 5 to 30 minutes. It is about.

[Conventional technology]

Generally, clay is used to extrude interior and exterior materials and roofing materials in a predetermined shape, and immediately cut this into a short length, for example, 10 to 30 cm in length, and dry this structure using the waste heat of the firing furnace. Transport it to the device and use this device to remove water for 1 to 3 days.
It was reduced to 0% and supplied to the firing furnace.

[Problems to be solved by the invention]

A conventional clay molded body drying apparatus not only takes several days to dry, but especially a clay molded body longer than before can be transported immediately after extrusion without using an underlay plate,
It was inferior in productivity, increased costs, and required a vast site. Furthermore, in the conventional drying device that heats and dries the surface, if the drying time is shortened by 1 day, the surface layer will be dried first and the inside will not be dried, so the steam inside will cause roof tiles, tiles, and outer wall materials to dry. Twisting, cracking, and breakage occurred, and shortening the drying time was extremely difficult. Further, instead of drying by heating from the surface, a device by internal heating, for example, a microwave heater or a far infrared heater is also known. However, although the former microwave heater can reduce the water content of clay in a short time, the material to be dried cannot be heated up to about 130 ° C. and the water content cannot be dried to 1% or less. Further, the far infrared heater requires a longer drying time than the microwave, and
Although the heating zone is longer than the microwave,
The temperature could be raised to 0 ° C. Therefore, both heating devices have merits and demerits, and there is a disadvantage that they are not put into practical use. Further, since the energy is high when heated by microwaves, a large amount of water vapor fills the heating zone, and there are disadvantages such as dew condensation on the surface of the object to be heated, the inner wall of the heating zone, and delay of drying time. Moreover, since the heating zone of the microwave heating device conveys the object to be heated by the drive belt, the soft object to be heated contracts about 10% during conveyance and cannot absorb the dimensional difference. However, there is a defect that the object to be heated is deformed, warped, cracked, or broken due to the frictional resistance.

[Means for solving problems]

In order to eliminate such a defect, the present invention sends the extruded product to a microwave heating device through a transfer device consisting of a fli roller and a driving belt conveyor next to the extrusion port of the extrusion device, and the extruded product in that state It is constructed so that it can be conveyed to the next step through a wave heater, and extrusion and primary drying are smoothly and continuously extruded, continuous drying is free from deformation, warpage, twisting, cracking, and moreover The present invention proposes a rapid drying device for a clay molded body, which can absorb the volume shrinkage of about% and can be conveyed to the next step, and can achieve the primary drying in 5 to 30 minutes.

〔Example〕

Hereinafter, an embodiment of a rapid drying apparatus for a clay molded body according to the present invention will be described in detail with reference to the drawings. 1 (a) and 1 (b) are explanatory views showing a typical example of the above apparatus. In the figure, reference numeral 1 denotes an extruder for continuously extruding a raw material containing clay as a main material, for example, an extruded body A having a cross-sectional shape shown in FIGS. 2 (a) to (j). 100 depending on the thickness and width of extruded product A
It is about 2000 mm / min. It should be noted that clay is a natural product and has different components depending on each producing area, and these advantages and disadvantages are mutually offset to obtain a predetermined mixed clay. Specific examples are pottery stone, feldspar, kaolinite,
This is to crush halosite, metahalosite, kibushi clay, frog eye clay, Shigaraki clay, chamotte, etc. and add water to knead. If necessary, the clay will be ironed with a magnet. 2 is a transfer machine
And the driving belt conveyor 4 are arranged in this order, and the extruded product A sent from the exit of the extruder 1 is warped at the same speed as the extrusion speed and on the extension line of the exit. It is useful for smoothly and continuously carrying to the next process without deformation such as twisting. In particular,
The fli roller 3 is useful for transporting the extruded product A in the extruded state without static friction resistance, and the drive belt conveyor 4 is somewhat harder than when extruded at a position about 0.5 to 2 m away from the outlet, and at the time of extruding. In order to prevent the above-mentioned force from being compressed due to the weight of the extruded portion which has been extruded first and thus preventing it from shrinking, the extruded product A is continuously transferred to the next step at substantially the same speed as during extrusion. . Reference numeral 5 denotes a microwave heater, which has an oven continuous system structure and mainly penetrates into the inside of the extruded body A so that the microwave B does not require much time for heat conduction.
Is converted into heat energy, and heat is generated in a few seconds to a few minutes to evaporate 5 to 10% by weight of water in the clay. In addition, the moisture content of the extrusion molded body A is 22 to 20% by weight.
It is contained in about 15%, and 5 to 10% of it is evaporated. In particular, this type of extruded product A has a water content of 5
The volume shrinks up to about 8%, but the volume does not shrink when the water content is less than that. Therefore, the microwave heater 5 will be described in detail. A microwave guide 5 for guiding the microwave B oscillated from a microwave oscillator (not shown) to a required location and a reflector 7 for reflecting the guided microwave B are provided. Conveyance part 10 consisting of rotary blade 8 for stirring reflected microwave B and frill roller 9 for moving extruded body A at the extruding speed and serves as an inlet and an outlet of extruded body A, and the microwave does not leak to the outside. And the air supply port 14 for guiding the air C to the heated space 13 and the surrounding body 15 so that the microwave B does not leak from the heated space 13 to the outside. It is a thing. The size of the heated space 13 of the extruded body A varies depending on the purpose, but is, for example, about 1 to 5 m. Further, the conveying unit 10 is about 1
Since the volume shrinks by about 10%,
It is absorbed by. Further, the air supply port 14 releases a large amount of water vapor C'in a short time by heating the microwave B to the outside through the inlets, outlets 11a and 12a, and the surface of the extrusion molded body A and the enclosure. Prevents dew condensation on the inner walls of 15 to prevent adverse effects (cracks, explosions) during drying,
In addition, the steam on the surface of the extruded product A is constantly blown off by the wind to help shorten the drying time.

Next, the operation will be described.

First, a clay consisting of Shigaraki clay, chamotte, a water reducing agent and water is prepared as a raw material. The weight% is, for example, Shigaraki clay 61.5%, chamotte 18%, water reducing agent 0.5% (trade name:
Cell Flow, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., water 20% clay mixer (MP
-100 type manufactured by Miyazaki Tekko Co., Ltd.). Also,
As the extrusion molding machine 1, a model name MV-FM-A-1 type (manufactured by Miyazaki Tekko Co., Ltd.) having an extrusion capacity of 100 to 150 / hr was used. Also,
The transfer machine 2 is installed on the extension line of the outlet, and then the microwave heater 5 is arranged, and the transfer unit 10 is installed on the extension line of the transfer machine 2 , that is, from the exit of the extrusion molding machine 1 to the microwave heater 5. The exit is the same pass line. The microwave heater 5 has a frequency of 2450 MHz, an output of 5 kw,
The length of the heated space 13 is 3 m, and air C etc.
A large amount of water is supplied from the air supply port 14 of the enclosure 15, and the water vapor C'generated during heating is discharged to the outside from the inlets / outlets 11a, 12a to lower the water vapor C'in the heated space 13, The heating object and the inner wall of the enclosure 15 are configured to prevent dew condensation water from being generated. In the microwave heater 5 , the moisture content of the extruded product A was set to 18% (wt%) to 5% (wt%) and the remaining moisture was vaporized by a far infrared heater (not shown). Further, the extrusion speed of the extruder 1 is 300 to 1000 mm / min, and here it is 400 mm / min. In addition, the pass lines of the extrusion-molded body A (here, a continuous-molded body) have the same height, and the extrusion-molded body A is fed to the microwave heater 5 by the driving belt at the same extrusion speed of the extruder 1. , The transfer part 10 in the microwave heater 5
The frill roller 9 is configured to absorb the difference in speed due to the volume contraction that occurs when water is evaporated. Therefore, the clay supplied to the extruder 1 is discharged from its outlet as shown in FIG. 2 (g).
It is delivered in a continuum of the cross section shown in. The extruded product A sent out is smoothly sent as it is at the extrusion speed to the microwave heater 5 via the transfer device 2 . Then, while passing through the heated space 13 of the microwave heater 5 , the moisture of the extruded product A is reduced to 5%.
% (Weight ratio) is reduced in 5 minutes, and it is fed from the outlet 12a to a heater (not shown) in the next step, and the heater evaporates water to 1% (weight ratio) in about 10 minutes to dry it. did. As a result, the extrusion molded body A in which the outlet 12a of the microwave heating machine 5 is made into a continuous strip from the outlet of the extrusion molding machine 1 is about 15
It could be delivered to the next step as a semi-dried product in about 20 minutes.

What has been described above is only one example of the quick-drying device for a clay molded body according to the present invention. A blower circuit with a heater is provided at a position indicated by a chain double-dashed line in FIG.
14 can be removed if necessary.

〔The invention's effect〕

As described above, according to the rapid drying apparatus for a clay molded body according to the present invention, an extruded molded body containing 22 to 15% (weight ratio) of water can be smoothly formed into a soft continuous extruded molded body from the outlet of the extruder. It is sent to the microwave heater (primary dryer) without deformation, and the microwave heater absorbs the volume shrinkage of the extruded product during drying without adversely affecting the extruded product and sends it to the next process. The drying time is 1/100 to 1
/ 300 has a shortened feature. Further, in the present invention, since the process from extrusion to drying is linearly arranged, the long body can be smoothly semi-dried.

[Brief description of drawings]

1 (a) and 1 (b) are schematic configuration diagrams showing an embodiment of a quick-drying device for a clay molded body according to the present invention and a sectional view taken along the line ii, and FIGS. 2 (a) to (j) are It is explanatory drawing which shows the cross section of an extrusion molded body. 1 ... Extrusion molding machine, 2 ... Transfer machine, 5 ... Microwave heating machine.

Claims (1)

[Claims] 1. Between an extruder for extruding a raw material containing clay as a main material in a predetermined shape and an oven continuous microwave heater for reducing the water content of an extruded product delivered from the extruder in a short time. In addition, a transfer machine consisting of a fli roller and a drive belt conveyor that rotates at a speed substantially synchronized with the extrusion speed of the extrusion-molded body is provided on the same line as the pass line between the extrusion-molding machine and the microwave heater, and the microwave heating is performed. A quick-drying device for a clay molded body, characterized in that a conveying section of the machine has a free-roller structure and an air supply port is provided in a microwave heating zone.