JP2011207681A - Method of supplying cement raw fuel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of supplying cement raw fuel by which organic powder having low bulk density and dust explosiveness is granulated to obtain the cement raw fuel and the granulated cement raw fuel is efficiently transported to a cement plant.SOLUTION: The organic powder having explosiveness is granulated by a molder on site and the granulated organic powder having dust explosiveness is transported by a mobile vehicle and the transported organic powder having dust explosiveness is charged into a cement kiln or a boiler as the cement raw fuel.

Description

  The present invention relates to a method for supplying cement raw fuel. The present invention particularly relates to a method for supplying a cement raw fuel, in which an organic powder having a dust explosive property is supplied as a cement raw fuel.

  Organic powders with dust explosive properties such as waste urethane and waste toner discharged as industrial waste may cause dust explosions when handling them, so care must be taken in handling wastes. On the other hand, since some of these organic powders having dust explosive properties have a high calorific value, it would be advantageous if they could be reused as raw cement fuel.

  Also, when recovering dust explosive organic powder discharged from the factory, those with low bulk density are bulky, so they require a large space for storage and cannot be transported efficiently. The transportation cost will be high.

Japanese Patent No. 4316486

  In view of the above circumstances, the present invention makes it possible to obtain a cement raw fuel by granulating organic powder having a low bulk density and a dust explosive property. It aims at providing the supply method of the cement raw fuel which enables efficient conveyance.

In order to solve the above problems, according to the present invention, on-site dust explosive organic powder is granulated by a molding machine, and the granulated dust explosive organic powder is mobile. There is provided a method for supplying raw cement fuel to a cement factory, which is transported by a vehicle, and the transported dusty explosive organic powder is charged as cement raw fuel into a cement kiln or boiler.
The molding machine has a flat die granulation having a disk-shaped die provided with a large number of through-holes for molding, the rotation axis of which is oriented in the vertical direction, and a pressure roller disposed at the center of the die. A device is preferred.
The granulated dust explosive organic powder is preferably a pellet.
The pellets preferably have a diameter of 4 to 30 mmφ, a length of 5 to 70 mm, a moisture content of 5 to 30%, and a calorific value of 3000 kcal / kg or more.

  According to the method for supplying raw cement fuel according to the present invention, it is possible to obtain raw cement fuel by granulating organic powder having low bulk density and dust explosive properties, It is possible to efficiently transport such cement raw fuel.

It is a conceptual diagram which shows one Embodiment of the supply method of the cement raw fuel which concerns on this invention. It is a schematic diagram which shows an example of the flat die type granulator used by this invention. It is a schematic diagram which shows an example of the apparatus structure of the cement kiln utilized by this invention.

Hereinafter, an embodiment of a method for supplying raw cement fuel according to the present invention will be described with reference to FIG.
First, the mobile vehicle 1 goes onsite 2. A hook roll container 3 is mounted on the mobile vehicle 1, and a mobile molding machine / portable molding machine 4 is installed in the hook roll container 3. The on-site 2 is a generation source or storage location of dust explosive organic powder which is the object 5 of the cement raw fuel of the present invention.
In addition, although it is suitable to use a mobile type reduction container and a portable type reduction container, it is also possible to install a fixed type reduction container in the on-site 2 and to perform the process of the present invention.
As the mobile vehicle 1, in addition to the vehicle on which the hook roll container 3 as described above is mounted, any vehicle can be used as long as it can be separated. For example, an arm roll car etc. can be mentioned. Further, the hook roll container 3 in which the molding machine 4 is installed can be detached from the mobile vehicle 1 and temporarily installed on the site 2.
Examples of the organic powder having dust explosive properties include waste urethane, waste toner, powder paint, sludge dry powder, waste food powder, waste plastics, and rubber waste. The presence or absence of dust explosiveness is evaluated by the value of the lower explosion limit concentration measured by the lower explosion limit test (JIS Z 8818). Organic powder determined to be dust explosive by this evaluation can be a target of the cement raw fuel of the present invention.
The organic powder preferably has a maximum particle size of 40 mm or less and an average particle size of 5 mm or less. This is because if the particle size is smaller than this, there is no need for pretreatment such as pulverization, the granulation efficiency is good, and the input amount to the apparatus is easy to control.

Next, the organic powder having a dust explosive property is granulated on-site 2 by a mobile molding machine / portable molding machine 4 or a stationary molding machine (not shown).
The movable molding machine / portable molding machine 4 or the stationary molding machine (not shown) used in the present invention is a disk-shaped die having a large number of through holes for molding, the rotation axis of which is in the vertical direction. And a general flat die granulator having a pressure roller disposed at the center of the die. The operation method of the flat die granulator will be described with reference to FIG. A dust explosive organic powder, which is the object 5 to be treated, is introduced onto a disk-shaped die 11 provided with a through-hole for molding, and the pressure roller 12 is rotated on the die 11 so as to dust. The explosive organic powder is compressed and extruded by being pressed into the molding through-hole while being crushed by the pressure roller 12, and the dust explosive organic powder is granulated.
Next, regarding the operating conditions of the flat die granulator, the molding temperature is in the range of 50 to 110 ° C. The diameter of the through hole for molding is in the range of 4 to 30 mm. The rotation speed of the pressure roller 12 is in the range of 30 to 140 rpm.

The dust-explosive organic powder generated or stored at the on-site 2 contains moisture. In the flat die granulator, this amount of water can be adjusted. The water content varies depending on the type of organic powder that is the object to be treated 5. About organic powder with little water content, it is preferable to spray mist-like water | moisture content before introducing into a flat die type granulator. This is because the dust explosibility can be suppressed by increasing the amount of water in the organic powder in advance. About organic powder with much water content, water content can be adjusted by dehydrating with a flat die type granulator.
The amount of water contained in the dust-explosive organic powder is preferably contained to such an extent that it can be molded by a flat die granulator, for example, 40% or less. In particular, with regard to waste urethane, if the water content is at least 15% or more, it is possible to suppress dust explosiveness when introduced into a flat die granulator.

  The granulated dusty explosive organic powder (granulated product) 13 is preferably a pellet. Fine powder can be reduced by using pellets, so that dust explosiveness can be reduced and safety can be improved. Moreover, the bulk density can be raised and volume-reduced by using the organic powder with a low bulk density as a pellet.

  It is preferable that the pellets molded by the flat die granulator have a diameter of 4 to 30 mmφ, a length of 5 to 70 mm, a moisture content of 5 to 30%, and a calorific value of 3000 kcal / kg or more. This is because pellets having such specifications provide suitable fuel properties as cement raw fuel. Further, when such pellets are used as fuel for a burner of a cement kiln, the pellet diameter is preferably in the range of 4 to 15 mmφ, and when used as auxiliary fuel for a preheater in a boiler, the pellet diameter is preferably in the range of 10 to 30 mmφ. .

  Unlike the screw type RPF / RDF production equipment that requires high pressure and high temperature, the flat die type granulation equipment has an open structure, so it can safely remove moisture or steam contained in organic powder. And it can discharge efficiently. In addition, since it is molded at a low pressure, it is difficult to enclose moisture in the granulated organic powder (granulated product) that has explosive properties, and excess moisture in the granulated product is dehydrated and removed from the system. Can be discharged. Furthermore, since the temperature of the granulated product does not rise, there is a low possibility that the granulated product will ignite, and it is not necessary to add water to prevent ignition trouble when storing the granulated product.

Next, the granulated dusty explosive organic powder 13 is transported by the mobile vehicle 1 (reference numeral 6 in FIG. 1).
The granulated material (pellet) 13 described above is stacked on the hook roll container 3, and the hook roll container 3 is mounted on the mobile vehicle 1 and transported to the cement factory 7. As described above, since the bulk density during transportation can be increased by using pellets, the transportation cost can be reduced, and the price advantage as a cement raw fuel can be increased.

Next, the conveyed organic powder 13 having a dust explosive property is put into a cement kiln 21 or a boiler as a cement raw fuel.
The apparatus structure of the cement kiln 21 which throws in the granulated material (pellet) 13 mentioned above as the cement raw fuel 32 is demonstrated using FIG.
The cement kiln (firing furnace) 21 is a long cylindrical rotating body for firing the cement raw material 24 to produce the clinker 27. On the raw material supply side of the cement kiln 21, in order to preheat and decarboxylate the cement raw material 24 and to discharge the exhaust gas 25 generated in the cement kiln 21 out of the system, a preheater 22 composed of a plurality of cyclones, and calcining A furnace 23 is connected. A cooler 26 for cooling the fired product (clinker) is connected to the fired product discharge side of the cement kiln 21. Further, a burner 28, a pipeline 30 for supplying the cement raw fuel 32, and the like are provided on the fired material discharge side of the cement kiln 21 so that the raw material of the cement kiln 21 has a high temperature atmosphere of about 1450 ° C. at the maximum temperature. It is arranged. The pipe 30 has one end connected to the blower 31 and the other end connected to the burner 28. A storage / quantitative supply device 29 for storing the cement raw fuel 32 and supplying it to the pipeline 30 is connected to a predetermined point of the pipeline 30 (near the blower 31).

Next, the operation method of this cement kiln is demonstrated using FIG.
First, the cement raw material 24 is charged into the raw material charging port provided in the upper part of the preheater 22. The cement raw material 24 is preheated and decarboxylated while moving downward in the preheater 22 and the calcining furnace 23, and then moves from the kiln bottom into the cement kiln 21.
The cement raw material gradually moves in the cement kiln 21 having a gentle slope and rotating gently toward the front of the kiln where the burner 28 is disposed, and is baked in the process to become a clinker 27. . The clinker 27 is dropped into the cooler 26 from before the kiln of the cement kiln 21, cooled by the cooler 26, and then discharged.
The temperature inside the cement kiln 21 is controlled so that the maximum temperature of the raw material (the temperature of the raw material near the flame of the burner 28) is about 1450 ° C. In order to maintain such a high temperature atmosphere, the cement raw fuel 32 obtained in the present invention is replaced with pulverized coal which is the main fuel of the cement kiln 21 or in combination with pulverized coal from the burner 28 into the furnace. It is thrown.

The cement raw fuel 32 obtained in the present invention is temporarily stored in the storage / quantitative supply device 29. Instead of using the storage / quantitative supply device 29, the cement raw fuel 32 may be directly supplied to the pipe line 30 from the hook roll container 3 loaded with the cement raw fuel 32 described above.
The raw cement fuel 32 in the storage / quantitative supply device 29 falls into the pipe line 30 at a predetermined supply speed by a supply amount adjusting means such as a rotary feeder provided at the bottom of the storage / quantitative supply device 29. The dropped cement raw fuel 32 moves in the pipe line 30 toward the cement kiln 21 at a predetermined flow rate by the wind pressure from the blower 31, and from the fuel injection port of the burner 28 connected to the end of the pipe line 30. It is injected into the cement kiln 21 at a predetermined injection speed.
The cement raw fuel 32 thrown into the furnace is completely burned in a short time before landing on the furnace bottom by the flame from the burner 28. The combustion residue of the raw cement fuel 32 becomes a part of the clinker component. Since the cement raw fuel 32 is completely burned before landing, the quality of the clinker is not deteriorated.
In order to increase the processing amount of the cement raw fuel 32 per unit time, the cement raw fuel 32 may be introduced from the kiln bottom of the cement kiln 21 as indicated by an arrow A in FIG.

As described above, the amount of heat per volume is increased by using organic powder having explosive dust as pellets. Therefore, the raw cement fuel obtained in the present invention can be used as the above-mentioned cement kiln burner fuel as an alternative to fossil fuel.
Note that the raw cement fuel obtained in the present invention can be used as an auxiliary fuel for a preheater in a boiler, in addition to the above-described cement kiln burner fuel, as an alternative to fossil fuel.

As described above, according to the method for supplying raw cement fuel according to the present invention, it is possible to obtain raw cement fuel by granulating organic powder having low bulk density and dust explosive properties. This makes it possible to efficiently transport such raw cement fuel to a cement factory.
In addition, according to the method for supplying cement raw fuel according to the present invention, it is possible to construct an efficient cement raw fuel supply system for commercialization in consideration of work personnel, work place, processing amount, and the like.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely using an Example etc., this invention is not limited to an Example.

Examples 1-2
Waste urethane (Example 1) and plant dust (Example 2) were introduced from the hopper, and pellets were produced using a flat die granulator temporarily installed at each source. In addition, the waste urethane used in Example 1 contained a coarse product having a maximum size of about 40 mm. The results are shown in Table 1.

  From Table 1, in any of Examples 1-2, the bulk specific gravity increased by using pellets. This was particularly noticeable in Example 2. Therefore, waste urethane with low bulk density and dust explosive properties can be reduced in volume and granulated safely, and dust explosive waste urethane and the like can be used as cement raw fuel. It was confirmed that it could be reused. Therefore, it was shown that the above-mentioned cement raw fuel can be efficiently transported to the cement factory by using the method for supplying raw cement fuel according to the present invention.

DESCRIPTION OF SYMBOLS 1 Mobile vehicle 2 On-site 3 Hook roll container 4 Mobile molding machine / portable molding machine 5 Object 6 Transportation 7 Cement factory 11 Dice 12 Pressure roller 13 Granulated material 21 Cement kiln 22 Preheater 23 Calciner 24 Cement Raw material 25 Exhaust gas 26 Cooler 27 Sintered product (clinker)
28 Burner 29 Storage / Quantitative supply device 30 Pipe line 31 Blower 32 Cement raw fuel

Claims (4)

  On-site dust explosive organic powder is granulated by a molding machine, the granulated dust explosive organic powder is transported by a mobile vehicle, and the transported dust explosive A method of supplying raw cement fuel to a cement factory, characterized in that organic powder is fed into a cement kiln or boiler as raw cement fuel.   The molding machine has a flat die granulation having a disk-shaped die provided with a large number of through-holes for molding, the rotation axis of which is oriented in the vertical direction, and a pressure roller disposed at the center of the die. The method for supplying raw cement fuel according to claim 1, wherein the raw material is cement.   The method for supplying a cement raw fuel according to claim 1 or 2, wherein the granulated organic powder having dust explosive properties is a pellet.   The method for supplying raw cement fuel according to claim 3, wherein the pellet has a diameter of 4 to 30 mmφ, a length of 5 to 70 mm, a moisture content of 5 to 30%, and a calorific value of 3000 kcal / kg or more. .

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