JP2002059421A - Method for operating granular plastic granulation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a method for controlling the operation of a granular plastic molded article granulation apparatus for keeping the quality of a granular plastic raw material and ensuring high productivity. SOLUTION: A storage device 11 is arranged on the upstream side of a granulation apparatus 12 and a plurality of softening/melting/extrusion molding type granulators are used as granulators 13 and, when granulation operation abnormality is generated in a part of the granulators during granulation operation, this operation abnormality is detected and the gragulator having generated granulation operation abnormality is changed over to a manual operation mode on the basis of the granulation operation abnormality and, therafter, it is detected that the granulation operation abnormality is returned to a normal condition and the granulator returned to the normal condition is changed over to an automatic operation mode from the manual operation mode to continue the operation of the granulation apparatus in the automatic operation mode. A drying device 19 for drying moisture adhering to plastics is provided on the upstream side of the storage tank provided on the upstream side of the granulation apparatus and, further, a forcible cooling device 20 for a plastic molded article is provided on the downstream side of the granulation apparatus line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for injecting used plastic recovered from industrial waste and general waste into a furnace for use as a reducing agent or fuel in the operation of an industrial furnace such as a blast furnace. The present invention relates to an operation method of a granulating apparatus for granulating a granular plastic molded product suitable for charging.

[0002]

2. Description of the Related Art In recent years, among industrial wastes and general wastes, used plastics have rapidly increased, and the disposal thereof has become a major problem. In particular, plastics, which are high-molecular hydrocarbon compounds, generate a large amount of heat during combustion and are liable to damage incinerators, which makes it difficult to treat them in large quantities, and most of them are disposed of in landfills. I have. However, there is a great problem in terms of environment and resource utilization in disposing of used plastics as landfill or the like. In recent years, shortage of landfill sites and generation of harmful gases from incineration have become serious social problems.

[0003] On the other hand, there has been proposed a technique for solving the above-mentioned problem by utilizing used plastic as a reducing material for ore in a blast furnace or the like or as an auxiliary fuel. That is, many proposals have been made for solving the problem of dioxin generation by burning chlorine-containing plastics, and many techniques relating to efficient blowing techniques into high-temperature furnaces such as blast furnaces have been proposed.
For example, Japanese Unexamined Patent Publication No. Hei 9-137926 discloses that when used plastic generated as industrial waste or general waste is blown into an industrial furnace such as a blast furnace for the above-mentioned purpose, the used plastic is formed into a film. And the other ones are subjected to pre-processing and predetermined processing in different processes suitable for each type of used plastic, and by this, it is necessary to blow into the furnace. It aims to improve the properties of used plastic during storage and transport processes and during blowing into the furnace.

[0004] One of the important techniques for injecting used plastic as an ore-reducing material and fuel into a furnace of a blast furnace is particularly suitable for blowing the used plastic into the furnace of the blast furnace. There is a demand for the development of quality improvement technology for products to be processed into granular plastics having a particle size and strength, and the development of operation and operation technologies that can efficiently operate the plant for producing the granular plastics and ensure high productivity. You.

[0005] In response to such demands, the former technology for improving the quality of products is based on granules and lumps suitable for blowing used plastic recovered from waste into the furnace from the tuyere of a blast furnace. As a chemical processing method, a method of performing the following processing on used plastic has been proposed, which has contributed to improvement in product quality. That is, by performing an appropriate crushing and pulverizing treatment, a method of granulation and agglomeration, a method of performing an appropriate pretreatment such as crushing and pulverizing, and then performing a melting or semi-melting treatment to granulate, After performing appropriate pre-treatment such as crushing and pulverization, and then subjecting it to compression molding and granulating, and after performing appropriate pre-treatment such as crushing and pulverization, subject it to semi-melting At the same time, a method of granulating by applying a compression molding process (for example,
No. 6855, hereinafter referred to as Prior Art 1).

However, no specific proposal has been found for the latter operation and operation technique. In particular, there is no description on a preferable operation and operation method when an abnormal situation such as a failure occurs in a granulating apparatus which is a core of a granular plastic manufacturing plant. No specific proposal is found.

[0007]

According to the prior art 1,
FIG. 6 discloses a ring-shaped die-extrusion roll type forming machine (ring die granulator) 1 whose schematic cross-sectional view is shown in FIG.
Thereby, a granular plastic molded product is prepared. The ring die granulator 1 includes a ring die 2 that is driven and rotated about a fixed shaft, an extrusion roll 3 that rotates or rolls while the outer peripheral surface is in contact with the inner peripheral surface of the ring die 2, and a ring die. 2 comprises a cutter 4 mounted close to the outer peripheral surface. The ring-shaped die 2 is provided with a large number of die holes 5 radially penetrating the thickness of the ring. The ring-shaped die 2 is rotated in the direction of arrow K in FIG. 6, the charged raw material 6 is charged into the inside of the ring-shaped die 2, and the charged raw material 6 is crushed by the extruding roll 3 into the die hole 4. Push in. The charging material 6 is compressed by the ring die 2 and the extruding roll 3 and extruded to the outer peripheral surface side of the ring die 2 to form a cylindrical plastic compression molded product 7. The compression molded product 7 extruded from the ring-shaped die 2 is cut into a predetermined length by a cutter 4 provided with a cutting edge at a position at a predetermined distance from the outer peripheral surface of the ring-shaped die 2, and is formed into a cylindrical granular plastic. A molding 8 is obtained. Thus, a method of granulating a desirable granular plastic molded product having a columnar shape of a target size and capable of securing a predetermined strength in a raceway when blown from a blast furnace tuyere is disclosed. . According to the prior art 1, according to the plastic molding method, when passing through the die hole of the compression molding device, the plastic is only partially melted by the surface friction of the plastic, and the entire temperature is higher than the melting point. Therefore, it is not necessary to cool the granulated material, and as a result, it is possible to continuously process and increase the throughput.

However, in order to utilize the granular plastic molded product prepared by the method for granulating the granular plastic molded product as an ore-reducing material in the operation of a practical blast furnace, and to sufficiently exert its effect, the granular plastic molded product must be used. The blast furnace as a whole plant for producing granular plastic raw materials for blowing into a blast furnace, which is equipped with a granulating equipment including the above-described ring die granulator, while maintaining a high product quality of a molded product. It is necessary to develop highly productive equipment and its operation and operation technology capable of responding to the high technical demands of Japan.

Accordingly, the present inventors have determined the granulation conditions for obtaining a granular plastic molded product having better product quality by using a softening / melting-extrusion molding type granulator such as a ring die granulator. At the same time, it was decided to develop productivity improvement technology for the whole plant. To this end, the present inventors have focused on improving the yield based on the improvement of the quality of the granular plastic molded product, which also contributes to the improvement of the productivity.

The present inventors have repeated research from the above viewpoints,
The following invention was filed and a patent application was filed. That is, after performing a predetermined pretreatment such as an appropriate crushing or pulverizing treatment, a magnetic separation treatment of a metal substance, and a sorting and removing treatment of chlorine-containing plastic in the pretreatment process of the used plastic, the obtained used waste is further processed. A drying process is performed on the plastic, and a step of removing the attached moisture is added. The thus dried plastic is supplied to a granulating apparatus as a charging material. Further, after granulating the granular plastic molded product by the granulator main body, a step of promptly performing an appropriate cooling process on the granulated plastic molded product is added. By doing this,
Ensuring the particle size and improving the strength of the granular plastic molded product, improving productivity by increasing the line flow capacity in the process after granulation, and causing thermal damage or fire in the product storage silo due to accumulation of sensible heat of the granular plastic molded product Has proposed a plant for producing granular plastic raw material for blowing into an industrial furnace, which can eliminate the danger of the above.

[0011] The present inventors have found that the above-mentioned plant for producing the granular plastic raw material for industrial blow-in charging stably maintains high productivity and operates with high efficiency. Is supplied to the industrial furnace in a stable manner and a large amount of used plastic recovered from waste can be continuously received. When the starting and stopping of the granulating apparatus is required due to an equipment failure of the plastic granulating apparatus, which is the core of the manufacturing plant, or a facility abnormality or an abnormality in the process below the granulating apparatus. Also focused on the importance of minimizing the effects and avoiding a complete shutdown of a wide range of equipment upstream of the granulator.

The inventors of the present invention, as a subject of the present invention, presuppose that the quality of a granular plastic molded product is maintained at a high level, and impede the normal operation of the above-mentioned granulating apparatus. When an abnormal situation occurs, particularly when an abnormal situation occurs in the granulator constituting the granulating apparatus, it is possible to avoid stopping the group of facilities on the upstream side of the granulating apparatus, particularly in the manufacturing plant. The idea is to create a driving method for operation. By solving this problem, it is possible to maintain a high level of quality of the granular plastic raw material for blowing and charging into the furnace of an industrial furnace such as a blast furnace, and furthermore, the equipment failure that occurs in the granulating apparatus. It is possible to eliminate damages such as equipment stoppages over the entire or a wide range of the manufacturing plant due to abnormal situations such as the above, and to reduce the opportunity loss for production. An object of the present invention is to provide an operation method of a granulating apparatus provided in a manufacturing plant of the granular plastic raw material.

[0013]

Means for Solving the Problems The present inventors have conducted intensive development research from the above viewpoints and obtained the following findings.

(1) First, in order to grasp important quality characteristics as a granular plastic raw material for injection charging into the furnace of an industrial furnace such as a blast furnace, a hot model test on the injection of a granular plastic molded product into the blast furnace is performed. Combustion experiments were repeated using the apparatus. As a result, the following findings were obtained. That is, it was found that it is necessary to produce a granular plastic raw material having an appropriate particle size and strength in order to blow it into the furnace of a blast furnace and use it as a reducing material and fuel for ore. On the other hand, the granular plastic molded product 8 granulated by the ring die granulator 1 (see FIG. 6) is finely pulverized, and the charged raw material 6 as a plastic is introduced into the die hole 5 by the extrusion roll 3. In the process of being bitten and crushed, it is heated and compressed by the energy caused by the compressive and frictional forces, and at least a part is softened, semi-melted or melted, the volume is reduced and at least a part of the surface is softened and melted It has properties. In the property characteristics of the granular plastic molded product 11, its particle size and strength are important, and it is important to satisfy favorable conditions of combustion efficiency when blowing from the tuyere into the blast furnace.
For this purpose, the hole diameter (diameter) d of the die hole 5 and the effective thickness T of the ring die satisfy the condition for improving the combustion efficiency, and further, the particle size D of the plastic as the raw material 6 is taken into consideration. To decide. From this perspective, for example,
The diameter d of the die hole is in the range of about 3 to 10 mm, the effective thickness T of the die hole is in the range of about 50 to 80 mm, and T / d is preferably in the range of 10 to 12. , D / d = 1.2-3. An example of a desirable size of the granular plastic molded product 11 is 6 mmφ × 10 mm length.

As described above, a "softening / melting-extrusion molding granulator" represented by a ring die granulator is used as a granulator.
It is desirable to use such a granulator to granulate plastic crushed to an appropriate size under predetermined granulation conditions into a blow pipe at a tuyere portion of a blast furnace and a raceway. It was found that good combustion characteristics were exhibited.

(2) Next, when an abnormal situation occurs in which the normal operation of the granulator cannot be continued during the operation of the granulator, particularly, on the upstream side of the granulator. An operation operation method that can avoid the stoppage of the equipment group is required. Such abnormal situations include, first of all, equipment failure of the granulator itself, and other upstream or downstream auxiliary devices and mechanisms dedicated to the granulator, such as a raw material charging mechanism and a granular Cutting out of the plastic molded product, failure of the unloading mechanism, and the like.

In such a case, generally, a storage tank for temporarily storing the charged material is provided upstream of the granulator, and the granulating operation of the granulator is continued until the storage tank is full. We will also work to eliminate the causes of the above abnormalities. Although the production efficiency of the granulator is appropriately reduced, when the storage tank is full, the upstream side of the granulator must be stopped over a wide area. In order to extend the time until such a facility stop state, two or more granulators are provided in parallel.

The present inventors provide two or more granulators in parallel, for example, two granulators, and normally operate two granulators at the same time. When the granulation operation cannot be performed due to the above, or when it is predicted, the granulation operation is immediately detected, and the granulator having the abnormality is excluded from the normal operation target based on the detection information.
Then, when the abnormality is removed, the normal operation target is returned again, and the two units are operated together. With this configuration, attention was paid to the fact that the frequency of stoppage of the equipment group on the upstream side and the stop time per operation were reduced compared to the granulation apparatus. Furthermore, the operation of the granulator is based on automatic operation, and during normal normal operation, the two granulators are operated in the automatic operation mode, and the granulator for which abnormality is to be generated is switched to manual operation. It is more desirable to switch to the operation of only one unit and to automatically switch to the original automatic operation mode of the two units again based on the recovery information of the abnormal granulator.

Next, when the granulating apparatus provided with the above-mentioned two or more granulators is operated by the above-described operation method, the equipment of the plant for producing a granular plastic raw material into which the granulator should be incorporated. In terms of the configuration, we studied and examined what equipment should be installed in order to improve the product quality of the granular plastic molded product and to make the manufacturing plant exhibit high productivity. The results will be described.

(3) The operation of rapidly cooling the granular plastic molded product granulated by the ring die granulator is performed when the granular plastic molded product granulated by the ring die granulator is used to cool the granular plastic molded product. Since the particles are extruded from the ring die at a temperature relatively close to the melting temperature, the granular plastic molded product discharged from the ring die granulator is rapidly cooled to an appropriate temperature or less at an early stage, thereby fusing particles together. It is possible to prevent coarsening or coarse agglomeration due to the above, and also to prevent overheating damage and incidents such as fire of incidental facilities such as silos for storing products due to heat accumulation of the discharged granular plastic molded products. Becomes possible. Furthermore, in order to ensure high productivity of the granular plastic molded product by the continuous operation of the ring die granulator, the cooling operation requires a high mass flow capacity of the granular plastic molded product in the downstream direct connection step. In this way, adding an appropriate cooling operation to the granular plastic molded product can improve the quality of the product, prevent overheating damage to ancillary facilities and prevent fires, and can further reduce the amount of the granular plastic raw material. The present inventors have found that it is desirable and extremely important from the viewpoint of improving productivity.

(4) The present inventors further conducted the above experiment to
The following items were found. That is, the pre-processed plastic loaded into the ring die granulator is dried to reduce the amount of water attached thereto, whereby hardened granulation becomes possible, and the strength of the granular plastic molded product is improved. Was found. For example, by using a substance having a predetermined particle size range in which the attached moisture is dried to 5 mass% or less,
It has been found that a granular plastic molded product having good combustion characteristics in a blow pipe and a raceway can be obtained as a raw material to be charged into a blast furnace. However, when the amount of attached moisture is large, even after the granulation treatment by the ring die granulator, the plastic exhibits a fluffy fluffy state, and the desired granulation is not performed.

The inventors of the present invention granulate a predetermined plastic from which adhering moisture has been removed by drying with a ring die granulator to prepare a granular plastic molded product. By rapid cooling, when injected into the blast furnace, the combustion characteristics of the granular plastic molded product, that is, the granular plastic raw material in the blow pipe and the raceway at the tuyere of the blast furnace are improved. Rate was found to improve.
By blowing and charging the granular plastic raw material thus manufactured into the blast furnace, the replacement ratio of the coke charged into the blast furnace top by the granular plastic raw material is improved.
Furthermore, the product yield of the granular plastic molded article is improved by charging the dried plastic into the ring die granulator. Therefore, from a different viewpoint, the productivity of the granular plastic raw material is improved.

(5) The present inventors further provide a suitable storage device on the upstream side of the granulation device line, thereby widening the range of adjustment of the amount of raw material charged into the granulation device. As a result, unstable operation of this plant line due to fluctuations in the processing amount or failure of each unit upstream and downstream of the granulation unit, or fluctuations in the supply amount of used plastic recovered from waste, etc. We focused on contributing to the absorption of the factors and production-inducing factors, and as a result, increasing the operation rate of the granulator. In addition, by adding the mixing and homogenizing function to the storage tank for uniformity of properties such as the shape, dimensions, components and melting point of the dried plastic received in the storage device, granular plastic molding is performed. The focus was on improving the product characteristics of the product.

The present invention has been made on the basis of the above findings and viewpoints, and the gist thereof is as follows.

According to the first aspect of the present invention, there is provided a method for operating a granular plastic granulating apparatus, wherein a used plastic recovered from industrial waste and general waste is subjected to a pretreatment and then blown into an industrial furnace. Pretreatment equipment is provided to enable the production of granules used as charging raw materials,
On the downstream side of the line of the pretreatment facility, a storage device having a function of temporarily storing the plastic treated by the pretreatment facility and having a function of cutting out and supplying the plastic is disposed, and On the downstream side of the line, there is provided a granulating device for granulating a granular plastic molded product suitable for blowing and charging into the industrial furnace, using the plastic cut and supplied from the storage device as a charging material. And the granulator has:
To the inside of an industrial furnace equipped with multiple granulators,
An operation method of a granulating apparatus in a plant for manufacturing a granular plastic material charged by blowing,
It has the following features.

That is, the granulating apparatus is operated in the automatic operation mode, and in the automatic operation mode operation, at least two or more of the plurality of granulators are started to start the granular plastic molding. Perform a granulation operation to prepare the product, and during the granulation operation, among the granulators during the granulation operation,
When granulation operation abnormality occurs in some granulators,
The granulation operation abnormality is detected, and based on the information on the detected granulation operation abnormality, the part of the granulator in which the granulation operation abnormality has occurred is switched to the manual operation mode. By detecting that the abnormality has been restored to normal, and by switching the normally restored granulator from the manual operation mode to the automatic operation mode, the granulator continues to operate in the automatic operation mode. .

[0027] According to a second aspect of the present invention, there is provided a method for operating a granular plastic granulator according to the first aspect, wherein a softening / melting-extrusion type granulator is used as the granulator. It has features.

According to a third aspect of the present invention, there is provided a method for operating a granular plastic granulator according to the second aspect of the present invention, wherein
A plurality of die holes are provided, a ring-shaped die that is driven and rotated, and an extrusion roll that rotates or rolls while the outer peripheral surface is in contact with the inner peripheral surface of the ring-shaped die, and is supplied as the charging material. Further, the invention is characterized in that a ring-die granulator for extruding the plastic subjected to the drying treatment from the die hole and extruding a granular plastic molded product is used.

The operation and operation method of the granular plastic granulating apparatus according to the invention according to claim 4 is described in claims 1 to 3.
In the invention described in any one of the above, the method for operating a granulating apparatus in a plant for producing the granular plastic raw material, the production plant, further, in the line downstream portion in the pretreatment equipment, the storage tank A drying device for drying the adhered moisture of the plastic supplied to the granulation device is provided, and the granular plastic granulated by the granulation device is provided downstream of the granulation device line. The present invention is characterized in that it is a method of operating a granulating apparatus in a manufacturing plant when a cooling device for cooling a molded product by a dry processing method is additionally provided.

[0030]

Next, the present invention will be described with reference to the drawings.

FIG. 1 illustrates the positioning of a granular plastic granulation apparatus in a plant where the granulation apparatus is installed when the method of operating the same is performed.
The conceptual diagram of the structure of an equipment plant is shown. In the figure, 1
Reference numeral 2 denotes a granulator, and a plurality of granulators 13 are provided in the granulator 12. The method of the granulator 13 is a method in which crushed or crushed plastic is softened, melt-extruded, and processed into a granular plastic molded product.

A used plastic 9 collected from industrial waste or general waste is subjected to a predetermined treatment in a pretreatment facility 10, temporarily stored in a storage device 11, and then provided in a granulation device 12. To a plurality of granulators 13
Supplied as charge 6. The properties of the charged raw material 6 charged into the granulator 13 are as follows. The product of the granular plastic molded product 8 granulated by the granulator 13 is passed through a storage / discharge facility 14 to an industrial furnace 15 such as a blast furnace. Of the raw material charged by blowing into the furnace, ie, the granular plastic raw material 1
It must have characteristics suitable for use as 6. The granulating device 12 is a core device that controls the productivity in the manufacturing plant 17 of the granular plastic raw material 16 including various facilities from the pretreatment facility 10 to the storage / discharge facility 14 and the quality of the granular plastic raw material 16. , A plurality of granulators 13 and an accompanying mechanism.

The operation of the granulating apparatus 12 is usually
Operate in the automatic operation mode, and in principle, a plurality of granulators 1
All of 3 are subjected to a granulation operation. However, when a special process operation is performed, at least two or more granulators are operated for granulation. During such operation, some of the plurality of granulators 13 during operation, usually one of the granulators, are usually one of them. The equipment is configured so as to be able to detect the operational abnormality, and the granulating machine 13 in which such an abnormality has occurred is manually operated based on the information on the details of the detected operational abnormality. Switch to mode. In this state, the granulating operation is continued for the operating granulator 13 which is not the abnormality occurrence target. Thereafter, it is detected that the abnormality of the granulator 13 has been restored to normal, and the normally restored granulator 13 is switched from the manual operation mode to the automatic operation mode. Storage device 1
As long as the one storage tank 18 is not full, the granulation operation is continued in this way, thereby avoiding a stop of a facility group constituting the pretreatment facility 10 on the upstream side.

The radix of the granulator 13 in the present invention is, for the production plant 17, from the viewpoint of improving the quality of the granular plastic molded product 8 granulated by this, from the viewpoint of softening and melting for the reasons described above. -It is desirable to use an extrusion-type granulator, and more preferably, to use a ring-die granulator 1 (see Fig. 6).

Next, in order to further improve the productivity of the manufacturing plant 17 by the operation and operation method of the granulating apparatus 12 according to the present invention, a conceptual diagram of the configuration of the equipment plant 17 shown in FIG. It is desirable that a drying device and a cooling device are additionally provided as shown in FIG. That is, as shown in the figure, a drying device 19 for drying the adhered water of the plastic which is online is provided at the most downstream part of the pretreatment equipment 10. Further, it is desirable to provide a cooling device 20 at the most upstream portion of the storage / discharge facility 14 for rapidly cooling the granular plastic molded product 8 discharged from the granulating device 12 to a predetermined temperature or lower.

FIG. 3 shows a schematic flow chart of the drying device 19. As a main unit of the drying device 19, a hot air drying processing device 21 as illustrated in FIG. 3 is used. 21
a is a burner, 21b is a hot-air generating furnace, 21c is a hot-air dryer, and 21d is a blower for sucking and conveying the dried plastic 9 '. In this way, the hot exhaust air used for hot air drying is applied to the dried plastic 9 ′.
Is desirably used as a gas for transporting to the next step. In this way, the drying efficiency of the plastic increases. In this case, a drying plastic separator 22 is provided at a downstream side of the drying device 19, and the dried plastic 9 ′ transported with the gas is dried by the drying plastic separator 22.
It is desirable to supply the dried plastic 9 ″ processed here and separated from the carrier gas to the storage device 11. The plastic separator 22.
In order to efficiently separate the plastic 9 ′ that has been conveyed by the cyclone mechanism or the gas, a large number of appropriate hole diameters that cannot pass through the plastic 9 ′ are formed. It is desirable that the plastic 9 'is mixed with the inflow of the plastic 9', the plastic 9 'is sucked to the outer peripheral surface of the ring-shaped sieve, and the sucked plastic 9' is scraped off and collected. If such a material is used, it is possible to manufacture an inexpensive material having a large processing capacity.

FIGS. 4 and 5 are schematic longitudinal sectional views of an example of a preferred cooling device for a granular plastic molded product. The cooling device 20 is desirably a dry-type device that can efficiently cool the granular plastic molded product 8 of about 100 to 150 ° C. or less.

FIG. 4 shows that the inside of the vertical cooling tower 23 is sucked by a suction blower 24 through a pipe to introduce atmospheric air, and the granular plastic molded product 8 on the ventilation cooling floor 25 is formed.
To cool. As another example, as shown in FIG.
A hood cover 27 is provided on the endless movable ventilation cooling floor 26,
This is provided with a suction blower 24 via a pipe. The atmospheric air is sucked by the suction blower 24 to cool the granular plastic molded product 8 loaded on the endless movable ventilation cooling floor 26. In this way, the temperature of the granular plastic molded product 8 is rapidly cooled to preferably 40 ° C. or less.

Thus, the product shape of the granular plastic molded product 8 is stabilized. A cut-out roller 28 as a discharge mechanism is provided at an outlet of the cooling device 20, and a discharge screw 29 as a discharge mechanism is provided downstream of the discharge roller 28 to store a granular plastic molded product 8 ′ in a storage silo (not shown in FIG. 2). (Included in the storage / discharge facility 14). In addition, as a discharge mechanism of the granular plastic molded product 8 ′ from the cooling device 20, an opening / closing rotary valve or a cutting roll or the like is used, and as a transport mechanism, a transport screw or a conveyor belt is used. Since the temperature has already dropped,
No heat-resistant structure is required. The cooling method in the cooling device 20 should be a dry cooling method. If water is contained, it is not preferable in terms of handling in the storage / transportation step in the subsequent step, and it is difficult to handle as a raw material to be blown into the industrial furnace 15.

[0040]

As described above, according to the present invention,
Used plastic recovered from industrial waste and municipal waste is converted into a granular plastic molded product suitable for use as a ore-reducing material by pneumatic blowing from tuyeres in the operation of industrial furnaces such as blast furnaces. In addition to being able to be processed into properties having excellent grain size and strength, any of the plurality of granulators provided has an abnormality in continuing the granulation operation, and the operation of the granulator is Even when it is necessary to stop the operation, the number of cases in which it is not necessary to perform the operation stop or partial operation stop or the like on the equipment group located on the upstream side of the granulator increases. Further, even when such an upstream-side facility group needs to be stopped, the stop time can be shortened, and the frequency of occurrence of such a stop is reduced. In this way, it contributes to maintaining high productivity of the entire production plant for the granular plastic raw material. In the manufacturing plant, an operation and operation method of such a granular plastic granulator can be provided, and an industrially useful effect is provided.

[Brief description of the drawings]

FIG. 1 is an example of a conceptual configuration diagram of an entire plant in which a granulating apparatus is provided when an operation and operation method of the granulating apparatus of the present invention is performed.

FIG. 2 is another example of the configuration conceptual diagram of the entire plant in which the granulating apparatus is installed when the method of operating the granulating apparatus according to the present invention is performed.

FIG. 3 is a schematic flow chart of an example of an apparatus for drying plastic after crushing and pulverization.

FIG. 4 is a schematic longitudinal sectional view of an example of a dry cooling device for a granular plastic molded product.

FIG. 5 is a schematic longitudinal sectional view of another example of a dry cooling device for a granular plastic molded product.

FIG. 6 is a schematic longitudinal sectional view of a main part illustrating a ring die granulator.

[Explanation of symbols]

 1 Ring Die Granulator 2 Ring Die 3 Extrusion Roll 4 Cutter 5 Die Hole 6 Charge 7 Plastic Compression Molding 8 Granular Plastic Molding 8 'Granular Plastic Molding 9 Collected Used Plastic 9' Dried Plastic 9 ”Plastic before drying 10 Pretreatment equipment 11 Storage device 12 Granulator 13 Granulator 14 Storage / discharge facility 15 Industrial furnace 16 Granular raw material 17 Manufacturing plant 18 Storage tank 19 Ring die granulator 20 Cooling device 21 Hot air drying apparatus 21a Burner 21b Hot air generator 21c Hot air dryer 21d Suction / transport blower 22 Dry plastic separator 23 Vertical cooling tower 24 Suction blower 25 Ventilation cooling floor 26 Endless movable ventilation cooling floor 27 Food cover 28 Cut out Roller 29 out screw 30 plastic metering feeder

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Nakatani 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nihon Kokan Co., Ltd. (72) Inventor Yasuaki Koyanagi 1-1-2, Marunouchi, Chiyoda-ku, Tokyo F-term (reference) in Nippon Kokan Co., Ltd. 4F201 AA50 AH81 AM32 BA02 BC01 BC06 BC12 BC25 BL09 BL25 BL34 BL36 BN21 4F301 BC56 BD09 BD34 BF16 BF31 4G004 LA06

Claims (4)

[Claims] 1. Pre-treatment of used plastic recovered from industrial waste and municipal waste to enable the production of granules to be used as a charge for blowing into an industrial furnace. A pretreatment facility is provided, and a storage device having a function of temporarily storing the plastic processed by the pretreatment facility and cutting out and supplying the plastic is provided downstream of the pretreatment facility line. And, on the downstream side of the line of the storage device, a granular plastic molded product suitable for being blown and charged into the industrial furnace, using the plastic cut out and supplied from the storage device as a charging material, A granulating device for granulating is provided,
Moreover, the granulating apparatus is provided with a plurality of granulators, and is operated by a method of operating a granulating apparatus in a plant for manufacturing a granular plastic material to be charged by blowing into an industrial furnace. Operating the granulating apparatus in an automatic operation mode, and in the automatic operation mode operation, starting at least two or more granulators out of the plurality of granulators to form the granular plastic molded product. Perform the granulation operation to prepare, and if the granulation operation abnormality occurs in some of the granulators during the granulation operation during the granulation operation, the granulation operation abnormality is detected. And, based on the information of the detected granulation operation abnormality,
The part of the granulator in which the granulation operation abnormality has occurred is switched to the manual operation mode, and thereafter, it is detected that the granulation operation abnormality has been restored to normal. An operation operation method of a granular plastic granulation device, wherein the operation is switched from an operation mode to an automatic operation mode to continue the operation of the granulation device in the automatic operation mode. 2. The method according to claim 1, wherein a softening / melting-extrusion type granulator is used as the granulator. 3. The softening / melting-extrusion molding type granulator, wherein a driving-rotating ring-shaped die having a plurality of die holes formed therein and an outer peripheral surface contacting an inner peripheral surface of the ring-shaped die. An extrusion roll that rotates or rolls, and extrudes the dried plastic supplied as the charge material from the die hole, and extrudes a granular plastic molded product. The operation and operation method of a granular plastic granulator according to claim 2, wherein a granulator is used. 4. The method of operating a granulating apparatus in a plant for producing the granular plastic raw material, wherein the granulation apparatus is further supplied to the storage tank at a downstream portion of a line in the pretreatment facility with respect to the production plant. A drying device for drying the moisture adhered to the plastic is additionally provided, and the granular plastic molded product granulated by the granulating device is subjected to a dry treatment downstream of the granulating device line. The method according to any one of claims 1 to 3, wherein the method is an operation method of a granulating device in a manufacturing plant when a cooling device for cooling by a method is additionally provided. Operation and operation method of the granular plastic granulator.