JPH03284341A - Method and apparatus for granulation treatment of molten sludge - Google Patents

Abstract

PURPOSE:To produce the granules of high strength by dropping molten sludge molten in a hot wind melting furnace on the center of the upper surface of a horizontal rotary disk in the high temp. atmosphere of a hermetic vessel sealed with water to make it into small spherical granules, and discharging them from the periphery of the disk to drop into water. CONSTITUTION:The molten sludge molten in the hot wind melting furnace 12 is dropped on the center of the upper surface of the horizontal rotary disk 6 to be made into small spherical granules, which are discharged from the periphery of the disk 6 into the air to be cooled and then dropped into water to be solidified and recovered. In this case, the molten sludge taking-out opening 13 of the furnace 12 and the disk 6 are provided in the vessel 5 which is airtightly sealed with the water of a water storage part 3 that has the water surface under the disk 6 and allows the granular bodies to pass through and to be taken out, so that the high temp. atmosphere is formed therein. The molten sludge discharged from the discharge opening 13 is directly dropped on the center of the upper surface of the disk 6. The small spherical granules formed on the disk 6 are discharged diagonally upward to the horizontal direction from the periphery of the disk 6 to be dropped on the water surface through the high temp. atmosphere with a certain lapse of time. The spherical granules are taken out through the water seal part 4.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for granulating molten sludge melted in a hot-air melting furnace and a processing apparatus therefor.

In recent years, securing a disposal site for various types of sludge, such as mud discharged from construction using the conventional Ashi shield tunnel excavation method, water-containing mud discharged from the coagulation and sedimentation process at water treatment plants, and sewage sludge, has become a major social issue in recent years. Therefore, in addition to reducing the volume of sludge by burning and melting it, recycling is required.

As a link to this, Honro Ganto previously filed the patent application No. 1-301.
No. 35 proposed a treatment method and apparatus that can economically melt and process hydrous sludge by increasing thermal efficiency by effectively combining drying, heating, and melting of hydrous sludge.

This has made it possible to economically melt and process various types of sludge and achieve volume reduction.

Conventionally, sludge melts obtained by melting sludge have been used at most as aggregates, road paving stones, and the like.

Therefore, if the sludge melt is granulated into spherical bodies with an appropriate particle size, its uses will be expanded and its added value will also increase.

Now, generally speaking, as a means of granulating a molten material into minute spheres, the molten material is dropped from a height at the center of the upper surface of a horizontally rotating disk, and the centrifugal force applied to the molten material by the rotation of the disk; The tangential force causes the melt drop to roll on the disk in the radial and circumferential directions, shaping it into a spherical shape.
A rotating disk type rapid granulator is known in which the material falls through the air from around the disk, is cooled during that time, and is further dropped into water to cool and solidify.

Note that Japanese Patent Publication No. 52-30149 is a prior art of a rapid granulation device for molten material using a rotating disk.

By the way, in this type of conventional granulation device, the molten material is once taken into a ladle from the molten material outlet of the melting furnace.

The melt was supplied onto a disc of a granulating device installed at a separate location for granulation, and both the melt outlet and the rotating disc were exposed to the atmosphere. Therefore, there is a drawback that thermal efficiency is reduced due to the hot gas inside the melting furnace that is discharged together with the melt and the room temperature air that flows back into the furnace from the exhaust port. In addition, the rotating disk is formed as a flat plate, and the granules ejected by centrifugal force are thrown out in a horizontal direction and are rapidly cooled and solidified by the low-temperature atmosphere, which has the disadvantage of decreasing strength. Ta.

In view of the above-mentioned actual conditions of the conventional sludge melt granulation method and apparatus, the present invention provides a sludge melt that can obtain sludge melt granules with good thermal efficiency and high strength. An object of the present invention is to provide a granulation processing method and apparatus.

In order to solve the above-mentioned problems, the method of the present invention is to drop molten sludge melted in a hot-air melting furnace onto the center of the upper surface of a horizontal rotating disk, granulate it into small spheres, and throw it into the air from the periphery of the disk. In a method for granulating molten sludge, which is taken out, cooled, dropped into water, solidified, and recovered.

(a) The melt outlet of the melting furnace and the rotating disk are placed in an airtight water-sealed tank that allows the granules to pass through and be taken out by water in a water storage section with a water surface below the rotating disk. (b) A step in which the sludge melt discharged from the melt outlet of the melting furnace is directly dropped onto the center of the upper surface of the horizontal rotating disk. (c) A small spherical shape formed on the rotating disk. A process in which the granules are ejected diagonally upward in the radial direction from the circumference of the disk and fall to the water surface over time in a high-temperature atmosphere; (d) The granules that have fallen to the water surface are solidified in water and collected at the bottom of the water; The process of taking the water out of the tank through the water seal section.

It is characterized by having the following.

Also, there is an apparatus of the present invention for carrying out this method.

The sludge melted in the hot air melting furnace is dropped onto the center of the upper surface of a horizontally rotating disk and granulated into small spheres.

In a granulation treatment device for sludge melt that is ejected into the air from the periphery of the disk, cooled, and dropped into water to solidify and recover, the sludge melt discharge port of the hot air melting furnace is located at the center of the top surface of the rotating disk. located directly above.

A water storage section that incorporates the sludge melt discharge port of the hot air melting furnace and the above rotating disk and has a water surface below the disk, and extends upward from the bottom of the water storage section and reaches a position higher than the water surface outside the tank. A granulation tank with a granule removal pipe.

A conveying means is provided in the granule removal pipe and conveys the granules from the bottom of the water storage part of the granulation tank.

It is characterized in that it is provided around the rotating disk and has a portion that is inclined radially outward and obliquely upward.

The apparatus for granulating molten sludge according to the present invention is constructed as described above, and the apparatus is used to carry out granulation according to the method described above. The melt produced and the hot gas discharged along with the melt are discharged into a granulation tank whose granulation take-out portion is sealed with water and airtight.

The temperature inside the granulation tank can be raised and maintained at a high temperature. Therefore, the gas flowing back into the furnace from the melt outlet has a high temperature, and there is little need to lower the hot gas temperature in the furnace.

The sludge melt that falls directly to the center of the upper surface of the disk from the melt outlet is granulated into minute spheres, and when ejected into the gas from the periphery of the disk, it is thrown diagonally upward by the slope around the disk. He was brought out and drew a line.

It falls onto the water surface of the water storage section at the bottom of the granulation tank. Therefore, the residence time in the gas becomes longer, and the atmosphere is maintained at a high temperature, so that the granules are slowly cooled over a long period of time, resulting in dense, high-strength granules.

The granules that have fallen into the water storage section are collected at the bottom of the tank, and are taken out of the granulation tank by a transporting means through a take-out pipe that extends above the water surface and has a water-sealing function.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the apparatus of the present invention for carrying out the method of the present invention will be described in detail below based on the drawings.

Figure 1 shows continuous melting and granulation in which molten sludge discharged from a hot-air melting furnace is granulated into microspheres using a rotating disk rapid granulator, and the granules are colored to produce colored beads. - It is a diagram showing the overall configuration of an embodiment in which the present invention is applied to a coloring processing device.

This apparatus is roughly divided into a granulation processing section 1 on the right side and a coloring processing section 2 on the left side for drying and coloring the granules collected from the granulation processing section 1.

The granulation processing section 1 has a water storage section 3 at its lower part, and a granulation tank 5 having an airtight structure to which a granule take-out pipe 4 extending from the bottom to a position higher than the water surface of the water storage section 3 is connected. , provided inside thereof above the water surface of the water storage section 3, h horizontal rotating disk 6. A shaft support 8 for supporting the shaft 7 passing through the bottom plate of the granulation tank. A motor 9 rotates this shaft, and the driving force of the motor 9 is transferred to the shaft 7.
It consists of a rapid granulator 11 consisting of a belt 10 that transmits to the granulator.

A peripheral portion of the rotating disk 6 is provided with a sloped surface 6a that slopes upwardly toward the outside in the radial direction over the entire circumference. Also, inside the rotating disk, a plurality of cooling water passages 6b are provided radially from the center, and a cooling water passage 7a is connected to a cooling water pump at the lower end of the shaft 7 and provided in the axial direction within the shaft 7. It is connected to the upper end and opens on the lower surface of the inclined outer peripheral part of the disk.

For example, the bottom of a hot air melting furnace 12 such as a swirl flow partial melting furnace is airtightly connected to the center of the top plate of the granulation tank 5, and is directly above the center of the rotating disk 6 of the rapid granulation machine 11. The melt outlet 13 of the melting furnace 12 is located at.

The bottom plate of the granulation tank 5 is inclined as a whole to become lower from the right end to the left end in the figure.

The granules that have fallen from the outer periphery of the rotating disk 6 of the granulator into the water in the water storage section 3 gather at the bottom of the left end.

A granule take-out pipe 4 is installed in this part toward the outside of the granulation tank and diagonally upward.
The lower end of the upper opening of the granule take-out pipe 4, in which a screw conveyor 14 as a granule conveying means is provided, is located above the liquid level of the water storage section 3, so that the granules are Although the body can be taken out, the granulation tank can be kept airtight and a water-sealing function can be achieved.

Next, the configuration of the coloring processing section 2 will be explained.

A drying chamber 21 for receiving and drying the water-wet granules discharged from the granule take-out pipe 4 of the granulation processing section 2 is provided directly below the outlet of the granule take-out pipe. A conveyor 22 is provided in the drying chamber, and an exhaust gas introduction pipe 23 of the melting furnace 12 is connected to the lower part of the conveyor 22. From the bottom of the drying chamber 21 at the bottom of the end of the conveyor 22, a granule conduit 24 extends to a hopper 26 at the top of a coating device 25, which is the main device of the coloring section. A feeder 27 is provided to feed the dry granules received in the hopper into the coating device in fixed quantities.

The coating device 25 includes a rotary disk 29 at the bottom of an upright cylindrical coloring tank 28, and above the outer periphery thereof is a supply pipe 3o from a feeder 27 and a spray nozzle 31 for spraying coloring agent at a different position. A zero-coloring tank 28 is connected to an exhaust gas introduction pipe 33 for introducing exhaust gas from the melting furnace 12 into the tank space below the zero-rotation disc 29 which is attached to the lower end of the colorant supply pipe 32. A product removal opening 34 is provided on the side wall at a position where the lower edge approximately coincides with the top surface of the rotating disk 29, and an outlet 35 for a drain or the like is provided on the bottom surface.

An exhaust gas pipe leading to a dust collector 36 is connected to the top plate of the drying chamber 21 and the coloring tank 28 of the coating device I25, and an exhaust gas pipe 38 is provided for discharging the collected exhaust gas to the atmosphere through an exhaust fan 37.

The operation of this device will be explained below.

The sludge melt melted in the hot air melting furnace 12 falls directly from the melt outlet 13 to the center of the rotating disk 6 of the rapid granulator 11 in the granulation tank 5, and is granulated into microspheres. The particles are pushed obliquely upward by the inclined portion 6a around the rotating disk 6, and fall into the water storage portion at the bottom of the granulation tank over time. Since the granulation tank 5 has a water-sealing function and an airtight structure, the granulation tank 5 is heated by the melt and the melting furnace hot gas discharged into the granulation tank. The atmosphere is kept at a high temperature, and the granules are slowly cooled over a long period of time to obtain a dense, high-strength product. You will get good results if you do this. Since the gas in the granulation tank 5 is maintained at a high temperature,
Even if the gas in the granulation tank flows back into the melting furnace 12 from the melt outlet 13, the temperature of the hot gas in the furnace is not reduced much.

- The granules that have fallen into the water in the water storage section 3 gather at the lowest part due to the slope of the bottom of the granulation tank, and from there are carried by the conveying means 14 through the granule take-out pipe 4 that extends obliquely upward to the outside of the granulation tank. After being transported on the water surface, it falls into the drying chamber 21.

The water-wet granules that have fallen into the drying chamber 21 are conveyed by the conveyor 22 and are dried by the heat of the melting furnace exhaust gas introduced through the melting furnace exhaust gas introduction pipe 23. It falls to the bottom of the drying chamber 21 and is collected in a hopper 26 via a conduit 24. The granules in the hopper 26 are transferred to the coating device 25 in predetermined amounts by the feeder 27.
As the one-rotation disk 29 rotates, the colorant sprayed from the spray nozzle 31 is evenly coated and heated by the exhaust gas from the melting furnace 12 that is supplied to the lower part of the one-rotation disk 29. The colorant is dried and fixed on the granules, and is taken out as a product from the outlet 34.

Note that the temperature of the exhaust gas introduced into the coloring tank 28 can be controlled by a temperature control air valve 40.

The exhaust gas whose temperature has been lowered by using heat in the drying chamber 21 and the tank 28 of the coating device is removed by a dust collector 36.
The air is discharged into the atmosphere from an exhaust pipe 38 by an exhaust fan 37.

As described above, the heat contained in the exhaust gas of the melting furnace is effectively utilized for drying the wet granules in the drying chamber 21 and for drying and fixing the colorant in the coating device 25, and is then discharged.

The granulation tank in the granulation processing section is configured to be airtight, and the molten material discharge port of the melting furnace opens directly above the rotating disk, thereby reducing heat loss and effectively utilizing the heat of the exhaust gas. Together, the thermal efficiency is significantly improved.

In addition, by making the sludge melt into colored small spherical particles,
This can be combined with a binder and used for beautiful wall materials, paving stones for roads, etc., increasing added value.

As described above, according to the present invention, it is possible to produce microspherical granules with higher strength than molten sludge with high thermal efficiency, which is effective in reducing the volume of sludge to be disposed of and recycling. Obtainable.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the overall configuration of an embodiment in which the present invention is applied to a sludge continuous melting, granulation, and coloring treatment device.・・・・・・
- Granulation tank 6... Rotating disk 6a... Inclined section 11... Rapid granulator 12... Hot air melting furnace 13... Melt discharge port 14...Screw conveyor (granule conveyance means) 21...Drying chamber 23.33...Melting furnace exhaust gas introduction pipe 25...
... Coating device 26 ... Hopper 27 ... Feeder 28 ... Coloring tank 29 ... Rotating disk 30 ... Granule supply Pipe 31... Spray nozzle 32... Colorant supply pipe 34... Product outlet 36... Dust collector 38... Exhaust gas pipe

Claims (2)

[Claims] (1) Molten sludge melted in a hot air melting furnace is dropped onto the center of the upper surface of a horizontally rotating disk, granulated into small spheres, ejected from the periphery of the disk into the air, cooled, and dropped into water to solidify. In a method for granulating molten sludge to be recovered, (a) the molten material discharge port of the melting furnace and the rotating disk are connected by water in a water storage section having a water surface below the rotating disk to allow the granulated material to pass through and be taken out; (b) A step in which the sludge melt discharged from the melt outlet of the melting furnace is directly dropped onto the center of the upper surface of the horizontal rotating disk. (c) A step in which the small spherical granules formed on a rotating disk are ejected obliquely upward from the circumference of the disk in the radial direction and fall onto the water surface over time in a high-temperature atmosphere; (d) When the particles fall onto the water surface. A method for granulating molten sludge, comprising the steps of solidifying the granules in water, collecting them at the bottom of the water, and taking them out of the tank through a water seal. (2) The molten sludge melted in the hot air melting furnace is dropped onto the center of the upper surface of a horizontally rotating disk, granulated into small spheres, ejected from the periphery of the disk into the air, cooled, and dropped into water to solidify. In the granulation treatment apparatus for sludge melt to be recovered, the sludge melt outlet of the hot air melting furnace is provided directly above the center of the upper surface of the rotating disk, and the sludge melt outlet of the hot air melting furnace and the rotating disk are a granulation tank having a built-in water storage part having a water surface below the disk, and a granulation take-out pipe extending upward from the bottom of the water storage part and reaching a position higher than the water surface outside the tank; A conveyance means is provided in the body extraction pipe and conveys the granules from the bottom of the water storage part of the granulation tank, and is provided around the rotating disk and has a portion that slopes outward in the radial direction and obliquely upward. A sludge melt granulation processing device characterized by: