JPS63192599A - Belt type dewatering drying machine - Google Patents

Abstract

PURPOSE:To improve the efficiency in dewatering by providing a far infrared radiation device at the adequate place at the peripheral side of the filter cloth traveling for a thin cake between filter cloths. CONSTITUTION:The dewatering part to form a thin cake by stretching upper and lower filter cloths around the roll 3 plurally arranged is made. In this case, far infrared radiation devices 4 in an adequate number are arranged at the adequate place of the peripheral side where the filter cloths 1, 2 travel. At the time when a shearing dehydration is executed between the filter cloths 1, 2 inside a sealed chamber after performing a gravitational dehydration with a sludge being supplied to the horizontal part 2a of the lower filter cloth 2, the far infrared radiation emitted from the device 4 projects the sludge to evaporate the moisture in the cake with its temp. up. The dehydration efficiency of a belt type dewatering drying machine is thus improved remarkably because of even the moisture among particles of the cake being dehydrated.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" This invention relates to an improvement in a belt-type dehydrator used for dewatering sludge.

``Prior art'' Conventionally, there is a belt-type dewatering machine commonly called a belt press, but in this type, concentrated sludge is concentrated by gravity dehydration, and then the sludge is concentrated using a press-low or a roller. It is dehydrated under pressure using a ring roll. Jitsuko 1986-
No. 35358 is one example, and there is a limit to dehydration in such a mechanical pressurizing operation, and the moisture content of the cake obtained by this method is about 75%. In order to further reduce this moisture content, there is a method to heat the cake during dehydration, as in Japanese Utility Model Application No. 59-180895.
-60604, which performs electroosmotic treatment on sludge during pressure dewatering, but even if these treatments are added, they only improve dewatering performance and cannot be expected to significantly reduce the water content. be.

"Problems to be Solved by the Invention" Conventionally, belt presses have produced a dehydrated cake with a moisture content of approximately 75%, compared to the cake moisture content of approximately 85% in vacuum dehydrators and centrifugal dehydrators. Also, compared to a filter press, the mechanism is simple and the dewatering operation is continuous; Inferior to moisture content of 70% or less, subsequent treatment of cake.

There are difficulties in disposal. In order to further reduce the water content of this dehydrated cake, heating and electrical treatments have been carried out as described above, but the desired results have not been achieved.

"Means to Solve the Problem" This invention is characterized by using a rational drying method different from the conventional concept of filtration and dehydration to reduce the moisture content of the dehydrated cake as described above. The gist of this is that it is a belt that is freely runnable between a number of rolls in which a pair of upper and lower poultices are lined up, and that dewaters the sludge that is supplied between the upper and lower poultices. In the type dehydrator, a device capable of irradiating far-infrared rays onto the thin cake formed between the pair of upper and lower compresses is installed at an appropriate location around the traveling area of the compresses.

"Function" This invention is configured as described above, and by irradiating far infrared rays onto a thinly dehydrated cake sandwiched between upper and lower compresses, the moisture in the cake absorbs the irradiation. It evaporates at elevated temperatures, and can even remove moisture between particles, which could not be separated by conventional pressurization or squeezing. However, this method of heating the cake using far infrared rays is
Compared to the heating means of Utility Model Application Publication No. 59-180895 mentioned above, which heats indirectly through media such as rolls or filter cloth,
Since the moisture in the cake is directly heated and evaporated, the heating efficiency is much higher. However, this far-infrared ray emitting device can be easily installed so as to irradiate a desired location, and control of its intensity is also easier compared to conventional heating devices.

In addition, the dehydrated cake that is irradiated with far infrared rays is diffused on the surface of the compress and is thin, so it not only dries easily but also has the advantage of being dried uniformly. This will be explained in detail based on the drawings.

``Example'' The dehydration drying device shown in Fig. 1 is designed to seal the filtration and dehydration section and irradiate far-infrared rays to the sludge cake sandwiched between the upper and lower filter cloths running inside this closed chamber. In the figure, 1 is an upper filter cloth, 2 is a lower filter cloth, 3 is a roll on which these compresses are spread, 4 is a far-infrared ray emitting device, 5 is a liquid receiving gutter, and 6 is a gas vent. be. Further, reference numeral 7 is a sludge thickener, 8 is a driving roll for compresses, and 9 is a scraper for peeling off cakes.

In the belt-type dewatering dryer configured in this way, the concentrated sludge is supplied to the horizontal part 2a of the lower cloth 2, where it is dehydrated by gravity, and then passed through the upper and lower filters between the rolls 3 provided in the sealed chamber. It travels while being sandwiched between cloths 1 and 2, is dehydrated by jarring action, is irradiated with far infrared rays, and is taken out of the machine, and the filtrate is taken out of the machine by the P liquid receiving trough 5. . That is, since the sludge is dehydrated into a thin cake and this thin cake is irradiated with far infrared rays, even water that could not be separated by mechanical pressure alone can be separated. However, in conventional belt presses, some of the water separated at the pressurized area (around the rolls) is
During the transfer to the next roll, it was absorbed into the poultice and cake again, but the dehydrator according to the present invention transpires these by irradiating far-infrared rays toward the surrounding area of the roll. reabsorption can be prevented. In addition, if the dehydration chamber is made into a closed chamber type as shown in Fig. 1, it can be easily made into a unit and connected to form a low)V 3 or far infrared ray generator 3.
can be increased correspondingly to obtain a cake of desired moisture content.

Next, what is shown in FIG. 2 is an example in which far infrared rays are applied to a commonly used belt press, and in this case, a far infrared ray generator is used to directly irradiate the dehydrated cake. With this configuration, it is structurally convenient to install far-infrared irradiation devices, and the irradiation direction and the number of devices to be installed can be freely selected. For example, as shown in the figure, it is also possible to easily irradiate the cake with far infrared rays from both the top and bottom sides.

The wavelength of far infrared rays used in the above examples is for dehydration and drying of sludge, so it is ideal to use one that is easily absorbed by water. Even something that warms the body has an effect.

"Effects of the Invention" As is clear from the above explanation, according to the present invention, it is possible to obtain a dehydrated cake that was impossible with mechanical pressure such as a conventional bellet press. In particular, the far infrared rays used in this invention are efficient because they act directly on moisture and raise its temperature, unlike conventional electric heating or hot liquid heating. The benefits obtained in sludge treatment are significant, such as easy control and easy automatic operation.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of a belt-type dehydrating dryer according to the present invention, and FIG. 2 is a schematic side view of another embodiment. Code explanation 1, Kamitofu 2. Shimotofu 3. Roll 4, far-infrared emitting device

Claims (4)

[Claims] (1) In a belt-type dehydrator in which a pair of upper and lower filter cloths 1 and 2 are freely runnable between rolls 3 in which many parallel filter cloths are arranged, and the sludge supplied between the upper and lower filter cloths is dehydrated, the above-mentioned A device 4 capable of irradiating far-infrared rays onto a thin cake formed between a pair of upper and lower filter cloths is attached to the filter cloth 1,
A belt-type dehydrator/dryer characterized by being installed at an appropriate location around the running area of No. 2. (2) The belt-type dehydrating dryer according to claim (1), wherein the far-infrared ray generator is installed around the running area of the upper and lower filter cloths with the cake sandwiched between the upper and lower filter cloths. (3) The far-infrared rays emitting device 4 is connected to the upper and lower filter cloths 1 and 2.
A belt-type dehydrating dryer characterized by being installed facing the cake on the lower filter cloth in a separated state. (4) The belt type dehydrating dryer according to claim (1), wherein the wavelength of the far infrared rays generated by the far infrared rays is 2 to 10 μm, which is efficiently absorbed by the water film. (5) The sludge A belt-type dehydrating dryer according to claim 1, wherein the pair of filter cloths 1 and 2 sandwiching the filter cloths run in a closed chamber.