JPH0729843B2 - Rapid drying equipment for clay compacts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is to dry an extruded product obtained by continuously extruding a raw material mainly containing clay in a predetermined shape in a short time of about 10 minutes to 1 hour. The present invention relates to a rapid drying device for a clay molded body, which can be cut during running to a fixed length.

[Conventional technology]

Generally, clay, inner and outer materials, roof tiles are extruded in a predetermined shape, immediately cut into a short length, for example, 10 to 30 cm in length, and a drying device having a structure that utilizes the waste heat of the firing furnace. In general, an apparatus having a structure in which the water content is reduced to 1 to 0% in about 1 to 3 days and then supplied to the firing furnace is common.

[Problems to be solved by the invention]

Not only does the conventional dryer for clay moldings take several days to dry, but especially clay moldings that are longer than before cannot be transported without the use of an underlay plate, resulting in poor productivity and increased costs. And required a vast site.
Furthermore, if the drying time is shortened by one day in the drying device that heats and dries from the conventional surface, the surface layer will be dried first and the inside will not be dried, so it will be twisted into the roof tile, tile, and outer wall material by the steam inside. , Cracks, warpage, and breakage occurred, and it was very difficult to shorten the drying time. 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, the former microwave heater can reduce the moisture content of clay in a short time, but it requires a large amount of energy to heat the material to be dried up to around 130 ° C, which is economical and economically harmful. It was difficult to dry to less than 1%. Further, the far infrared heater alone required a longer drying time than the microwave and the heating zone was longer than that of the microwave, but the object to be heated could be heated to 130 ° C. Therefore, both heating devices have merits and demerits, and there is a disadvantage that they are not put into practical use. Further, when heated by microwaves, the energy cost is high, and a large amount of water vapor fills the heating zone, which causes inconveniences such as dew condensation on the surface of the object to be heated, the inner wall of the heating zone, and delay in drying time. In addition, the heating zone of the microwave heater has a structure that conveys the object to be heated by the drive belt, so the soft object to be heated contracts about 10% during conveyance, and the difference in size cannot be absorbed so that the object to be heated is transferred between the belt conveyors. However, there is a defect that the object to be heated is deformed, warped, cracked, or broken due to the frictional resistance. Further, conventionally, it was impossible to consistently carry out the steps from the extruder to the traveling cutter.

[Means for solving problems]

In order to eliminate such defects, the present invention sequentially feeds a microwave heater and a far-infrared heater device through a transfer device that smoothly feeds the extrusion port of the extruder next to the next step. , The extrusion molded body is dried in a continuous state, and is cut to a predetermined length by a traveling cutter, the extrusion molded body does not deform, warp, twist, or crack during drying, and the extrusion molded body The present invention proposes a rapid drying apparatus for a clay molded body, which can absorb and transport the volume shrinkage of about 10% and can be dried in about 10 to 60 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. Reference numeral 2 denotes a transfer device, which is composed of, for example, a flea roller, or at least one driving belt (not shown) which is synchronized with the extrusion speed, and smoothly feeds the extrusion-molded body A to the next step without changing the extrusion speed. It is for doing. 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 0.5 out of the outlet.
It is somewhat harder than when it is extruded at a position about 2 m away, and the force at the time of extrusion is almost the same as that at the time of extrusion in order to prevent it from being compressed because it cannot resist the weight of the extruded extrusion that was extruded first. The extrusion molded body A is continuously transferred to the next step at the same speed. Numeral 5 is a microwave heater having a continuous oven structure, which mainly permeates the inside of the extruded body A and converts the microwave B into heat energy with almost no time required for heat conduction, and within a few seconds to a few minutes. This is for generating heat to evaporate the water content in the clay, for example, 5 to 10% (% by weight). In addition, the water content in the extrusion-molded product A is 22 to 15 by weight.
It is contained in about%, and 5 to 10% of it is evaporated. In particular, this type of extruded product A has a water content of 5 to 5.
The volume shrinks until it reaches about 8%, but when the water content is less than that, the volume does not shrink. Therefore, the microwave heater 5 will be specifically described. A waveguide 6 that guides the microwave B oscillated from a microwave oscillator (not shown) to a required location, and a reflection plate 7 that reflects the guided microwave B. A rotary blade 8 that stirs the reflected microwave B, and a flir roller 9 that moves the extruded product A at the extruding speed and irradiates the microwave B from the back surface of the extruded product A. The conveying section 10 , the inlets and outlets of the extruded body A, and the filter sections 11 and 12 that attenuate the microwave B so as not to leak to the outside and the air supply port 14 that guides the air C and the like to the heated space 13. And a surrounding body 15 that surrounds the microwave B so as not to leak from the heated space 13 to the outside. 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. Furthermore, the transport section
Since the volume of the extruded product A shrinks by about 10% during drying, the extruded product A is absorbed by the flea roller 9 without difficulty. In addition, the air supply port 14 is designed to release a large amount of water vapor by heating the microwave B in a short time.
Release from a, 12a to the outside, surface of extruded product A, enclosure
Prevents dew condensation on the inner wall of 15 to prevent adverse effects (cracks, explosions) during drying, and constantly blows off the steam on the surface of the extruded product A by wind to help reduce the drying time. Is. Reference numeral 16 denotes a far-infrared heater device using infrared rays, particularly far-infrared rays as a heat source, and the extrusion molded body A is 130% in order to reduce the water content of the extrusion molded body A to 1 to 0%.
It is intended to raise the temperature above ℃. Its structure is a transport mechanism 17 consisting of a fli roller and a drive belt and a far infrared heater 18.
And the heat insulation box 19, and the heating zone is about 2 to 5 m. Of course, the heating zone is a semi-dried extruded product A
The thickness depends on the thickness, width, size, and transport speed. Reference numeral 20 is for cutting a continuous extruded product A dried by a traveling cutter during traveling to a predetermined size, and is cut by using a circular saw blade or a laser (not shown), pressurized water or the like. It is a thing.

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 device 2 includes a fli roller 3, a drive belt conveyor 4
The microwave heater 5 has a frequency of 2450 MHz, an output of 5 kw, and the length of the heated space 13 is 3 m. If necessary, a large amount of air is supplied to the heated space 13 from one wall surface of the enclosure 15. The steam C'generated during heating is discharged to the outside through the inlets / outlets 11a, 12a, the steam pressure in the heated space 13 is reduced, and condensed water is generated on the heated object and the inner wall of the enclosure 15. The transport section 10 is the fli roller 9 made of a Teflon pipe. In addition, the far infrared heater device 16 includes a plurality of far infrared heaters 18, approximately 3
They are arranged in a zone of ~ 10 m, and the output is set to 20 kw, for example. 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 the far infrared heater device 16 . Furthermore, the extrusion speed of the extruder 1 is 300.
~ 1000 mm / min, and here 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 the extruder 1.
The microwave heating machine 5 is driven by the driving belt at the same extrusion speed.
And is adapted to absorb a difference in speed due to volume contraction caused by evaporation of water at the fli roller 9 of the conveying section 10 in the microwave heater 5 . Therefore, the clay supplied to the extruder 1 is delivered from its outlet in a continuous body having a cross section shown in FIG. 2 (g). The extruded product A sent out is sent to the microwave heating device 5 via the transfer device 2, and while passing through the heated space 13 of the microwave heating device 5 , the water content of the extruded product A is 5% (weight ratio). ) Is reduced in 5 minutes, and the far infrared heater device 16 is fed from the outlet to the far infrared heater device 16.
Then, the water content was evaporated to 1% (weight ratio) in about 10 minutes and dried. As a result, about 15 to 20 extruded bodies A having a continuous band from the outlet of the extruder 1 to the far infrared heater device 16 are obtained.
In minutes, it was fed as a dried body to the traveling cutter 20 and cut into a predetermined size. Of course, although not shown, it is also possible to subsequently feed the glazing or the firing process continuously.

The above description is merely one example of the rapid drying apparatus for a clay molded body according to the present invention, in which air, warm air, dry air, and hot air are used in combination at the position shown by the alternate long and short dash line in FIG. 1 (a). However, it is possible to further promote the drying of the extrusion molded body A. Further, the air supply port 14 can also suck the gas in the heated space 13 by a pump (not shown).

〔The invention's effect〕

As described above, according to the rapid drying apparatus for a clay molded body according to the present invention, 1/100% of the water content of the clay extruded molded body (short length, long length, continuous body) containing 22 to 15% (weight ratio) of water. Microwave heater that evaporates evenly in the 3rd place including the inside of the extrusion to dry without distortion, and far-infrared heater device that can efficiently heat the remaining 2/3 of the moisture content higher than microwave There are no cracks, explosions, twists, and warpages, and there is a feature that the drying time can be shortened to 1/100 to 300 of the previous one. In addition, the volume of the extruded product is 1 for the dried product as compared with that during extrusion.
There is a feature that the shrinkage of more than 50% absorbs the influence on the conveying speed due to the shrinkage, and it can be transferred to the next step. Further, in the present invention, since the process from extrusion to drying is linearly arranged, a long body or the like can be smoothly 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, 5 …… Microwave heating machine, 16 …… Far infrared heater device, 20 …… Running cutter.

Claims (1)

[Claims] 1. An extrusion molding machine for continuously extruding a raw material mainly made of clay in a predetermined shape, and an oven continuous microwave for reducing the water content of an extrusion molding product sent from the extrusion molding machine in a short time. A heater, a far-infrared heater device that mainly raises the temperature of the extruded product that has passed through the microwave heater, and a travel that cuts the continuously dried extruded product that has passed through the far-infrared heater device to a fixed length A quick-drying device for a clay molded body, which is arranged in series in the order of a cutter.