WO2010024545A2 - A method for the autothermal manufacture of fired material using a vertical furnace - Google Patents

Abstract

The present invention relates to a vertical, autothermal furnace characterised in that it comprises a furnace that tapers with the lower part wider than the upper part and having a spherical, elliptical or polygonal cross section, said furnace being replenished with carbon-containing pellets; a pellet filler opening; a discharger; and an air regulator. The present invention further relates to an autothermal method of manufacturing fired material comprising the steps of filling said vertical autothermal furnace with carbon-containing pellets and preheating, and then continuously loading carbon-containing pellets into said preheated pellet-loaded furnace, and continuously discharging said autothermally fired material produced by the autothermal firing of said carbon-containing pellets from the lower part thereof. The method of manufacturing fired material using said furnace has the economic advantage of enabling the autothermal firing of pellets using only the heat generated during firing without additional heating.

Description

Method for manufacturing autothermal plastic body using vertical kiln

The present invention relates to a vertical autothermal firing furnace wider than the upper portion and a method for manufacturing the autothermal firing body.

In the general calcined body manufacturing process, pellets are calcined at a predetermined temperature by external heating in a stocker or rotary kiln type kiln to obtain a calcined body.

In the case of the stalker-type kiln, the combustion heat is used by containing some carbon component, but the autothermal calcination in the full sense is difficult, and the stalker-type stalker has a problem in that the furnace is driven at a high temperature due to its low durability. Economic operation is difficult due to the increase in operating costs.

Rotary kiln type kiln is mainly used for the firing of volcanic ash, and the kiln is configured to charge about 15% of the internal space of the kiln and to be fired by indirect heating by a burner, so that thermal efficiency and work efficiency are low. In the case of pellets made by agglomerating powders, there is a disadvantage in that the plasticity is difficult to maintain because the cohesiveness is lowered at a specific temperature range during firing and the shape of the pellets is difficult to maintain due to wear.

In order to solve the above problems, the present invention proposes a vertical autothermal firing furnace having a simple structure and no driving part even at high temperatures in order to more economically fire pellets.

And the present invention provides a method for producing a self-heating calcined body to autothermally fire with heat generated when the pellets are fired without additional heat supply.

In addition, the present invention proposes a method for preventing fusion due to overfiring by limiting the maximum temperature to a predetermined temperature or less according to the firing temperature of the pellet.

In order to solve the above problems, the present invention relates to a vertical autothermal firing furnace having a tapered shape and a wider lower portion than the upper portion.

In addition, the present invention relates to a method for preparing a fired body by autothermal firing after pellets containing carbon and preheated by filling the firing furnace, and continuously adding the pellets.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

The vertical self-heating kiln is a circular, oval or polygonal cross section of the lower tapered shape than the upper, filled with pellets containing carbon, such as coal, the pre-heated at a constant temperature so that the filled pellets autothermally fired (100 );

A pellet input unit configured to supply pellets into the firing furnace 100 in an upper portion of the firing furnace 100;

A discharge part 510 for discharging the pellets that have been autothermally fired in the firing furnace 100; And

It is provided on the firing furnace 100, characterized in that it comprises an air conditioning unit 310 for controlling the amount of air required for the autothermal firing of the pellets supplied into the firing furnace (100).

Here, the autothermal firing furnace refers to a firing furnace configured to sinter pellets with heat generated when firing pellets without additional heat supply.

The firing furnace 100 preferably has an inclination angle of 2 to 30 °, and a cross sectional area is widened from the top to the bottom. The shape of the firing furnace 100 is easily discharged by moving the pellets downward in the firing process. There is an advantage to doing this.

The air control unit 310 controls the amount of air supplied into the firing furnace 100, and by controlling the firing rate in accordance with the air supply amount to limit the maximum internal temperature to a predetermined temperature or less to prevent underfiring. The air control unit 310 is not limited significantly, but may be a communication type, it may be provided with a manned blower (I.D Fan (Induced Draft Fan)). In addition, the air control unit 310 may further include an air volume control device 300 and control the air control unit 310 through the air amount control device 300 to adjust the internal temperature and the firing speed of the kiln. .

In addition, the vertical self-heating kiln is installed adjacent to the temperature sensor 320 and the air control unit 310 provided to measure the temperature inside the kiln 100, the water level of the pellets filled in the kiln 100 It may further include a water level sensor 230 for measuring. The water level sensor 230 may use an optical sensor.

The temperature sensor 320 is provided with at least one, it is possible to measure the temperature inside the kiln according to the height of the kiln. More specifically, the firing furnace 100 may be provided in one or a plurality in a downward direction, and when provided in plural by varying the length of the temperature sensor, effectively measuring the temperature inside the vertical autothermal firing furnace according to the height. can do. In addition, the temperature sensor may be provided over the outside and inside of the kiln through the communication type air control unit 310.

In addition, the discharge unit 510 may be provided with a screw feeder or pin crusher to discharge a certain amount of the self-fired pellets.

When the pin crusher is provided in the discharge portion, there is an advantage that the pellet can be dismantled and discharged when a little fusion occurs while the pellet is fired.

The discharge unit, the air amount control device 300 and the temperature sensor is controlled by the controller 520.

In addition, the firing furnace 100 may be provided with a heater 400 or may be preheated to a predetermined temperature using combustion heat of fossil fuel.

The heater 400 may be used to preheat the pellet containing carbon filled in the firing furnace, but is not limited thereto, and any heat source capable of preheating the pellet may be used, and pellets continuously added after preheating may be used. It is autothermally calcined with heat generated during firing of the pellets.

The heater 400 may be provided in a band shape in contact with the inner surface of the firing furnace.

The pellet input part may include a feeder 210 for temporarily storing the pellet and supplying the hopper 200 to the inside of the firing furnace 100 and a predetermined amount of the pellets provided at the bottom of the hopper to be supplied into the firing furnace. The level of pellets in the kiln can be adjusted through the water level sensor 230 and the feeder 210.

As an example of the feeder 210, a vibrating feeder may be used, and the vibrating feeder is connected to the water level sensor and adjusts the amount of pellets containing carbon supplied from the hopper according to the vibration and tilt of the feeder. can do.

The feeder is not particularly limited, but may be connected to the communication air control unit 310 to supply the pellets.

Hereinafter, a method of manufacturing the autothermal fired body will be described in more detail.

The present invention is a step of preheating by filling the pellet containing the carbon into the vertical autothermal kiln, and the pellet containing the carbon continuously into the pellet containing the carbon into the preheated pellet It provides a method for producing a self-heating calcined body comprising the step of discharging the self-heating calcined body generated by the autothermal calcining.

When preheating pellets containing carbon filled in the vertical autothermal kiln, any heat source capable of preheating the pellet may be used without limitation, and may be preheated by using a combustion heat of fossil fuel or a heater provided in the kiln.

The heat source used in the preheating is necessary only for the first preheating, since the heat generated in the calcining reaction is possible due to the carbon contained in the pellets, so that autothermal calcining is possible.

The present invention is characterized in that the pellets introduced into the firing furnace is baked by maintaining 800 ~ 1300 ℃.

Carbon contained in the pellets may be subjected to autothermal firing during firing, and the carbon content is preferably 4.5 to 15% by weight, and when the carbon content is less than 4.5% by weight, autothermal firing does not occur effectively.

In addition, when the carbon content is more than 15% by weight, not only fusion occurs in the firing process but also has a disadvantage of longer firing time.

In addition, the pellet may contain 2 to 30% moisture. If the pellet contains less than 2% moisture, the durability of the autothermally calcined body produced after firing may be reduced or may be overfired. If the pellet contains more than 30% of water, the durability of the autothermal calcined body produced after firing may be Can fall.

Pellets containing water in the above range may be naturally dried with heat generated during the process of self-firing the pellets that are first introduced, and thus, the drying process is not necessary in the present invention and may have an economic effect.

The pellets are carbon-containing materials selected from coal waste-rock, coal and mixtures thereof, and red mud, dolomite, waste foundry sand, illite, pearlite, zeolite, diatomaceous earth, bentonite, vermiculite, manganese slag, clay, coal ash, fly ash, bottom ash and these It may include an inorganic material selected from the group consisting of a mixture of.

The autothermal fired body discharged by the autothermal firing is characterized in that the collapse strength is 5 ~ 200kgf /, the collapse strength may vary depending on the mixing ratio of the carbon-containing material and the inorganic material of the pellets, carbon content, firing temperature.

The collapse strength refers to the maximum pressure at the instant of breakage by applying pressure to the autothermal fired body at a constant speed in one axial direction, and the unit is kgf / piece.

In addition, the pellets used in the present invention are not particularly limited, but may be manufactured by molding into a spherical or oval shape having a diameter of 5 to 30 mm, and excellent durability when the autothermal fired body is manufactured in the above range. The method of molding the pellets is not particularly limited, and a machine such as a pelletizer may be used.

The present invention has the advantage that it is possible to treat the unused mineral resources and waste resources by manufacturing the autothermal calcined body without using additional fuel using coal ash, red mud. In addition, the manufactured autothermal fired body can be used as a lightweight aggregate and a porous ceramic fired body, which is expected to use industrially.

The kiln according to the present invention has the advantage that the pellets can be easily moved downward and discharged during the firing process because the cross-sectional area increases in the tapered shape toward the bottom of the kiln.

In addition, the present invention can be autothermally calcined without additional heat supply by using a pellet containing carbon, and the newly added pellets are naturally dried with heat generated during firing, thereby maximizing thermal efficiency by omitting the drying process.

1 shows a vertical autothermal firing furnace.

100 kiln

200 hopper

210 feeder

230 level sensor

300 Airflow Control

310 air conditioner

320 temperature sensor

400 heater

510 outlet

520 controller

Hereinafter will be given an embodiment for a specific description of the invention. The following examples are only for illustrating the present invention, but the scope of the present invention is not limited thereto.

Example 1

Vertical Autothermal Furnace Standard

Firing furnace 100 is a tapered vertical self-heating kiln, the cross section is circular, the upper diameter of 80mm. A fire resistant castable material having a lower diameter of 100 mm and a height of 300 mm was used.

Hopper 200 and the vibrating feeder 210 was provided on the top of the kiln.

A pin crusher was installed at the lower part of the kiln to discharge the pellets, and an air control unit 310 was provided with an ID fan (Induced Draft Fan). In contact with the air volume control device 300 was installed.

Three 50mm, 100mm and 150mm length temperature sensors 320 were provided in the downward direction from the top of the kiln so as to penetrate from the outside to the inside of the kiln, and provided with an optical sensor which is a water level sensor 230 adjacent to the temperature sensor. The level of the pellet was measured to control the feeder speed.

The heater 400 was installed in a band shape on the upper inner surface of the kiln, but the heater 400 was installed at a height of 200 mm to 300 mm from the bottom of the kiln.

Carbon-containing Pellet Manufacturing

30 g of water, 55 g of coal ash (F.C1.3%), 20 g of pearlite, 15 g of anthracite (58.3% of fixed carbon (FC)), 10 g of dolomite were mixed, and the mixture was molded into a 10 mm diameter sphere to pellet ( Fixed carbon (FC) 8.74%) was prepared.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The pellets were filled in a vertical autothermal kiln, preheated the heating wire of the heater so that the internal temperature of the kiln was 750 ° C, and new pellets were continuously added, and the maximum limit temperature of the kiln was limited to 1100 ° C.

At this time, after preheating, the autothermal firing was performed while the power supply of the heating coil of the heater was cut off. The autothermal calcined body was continuously discharged through the outlet.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 2

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

It was prepared in the same manner as in Example 1.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1 except that the firing furnace maximum limit temperature was 1050 ° C.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 3

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

It prepared in the same manner as in Example 1.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (industrial analysis method of coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1 except that the firing furnace maximum limit temperature was 1000 ° C.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 4

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30 g of water, 50 g of coal ash (F.C1.3%), 20 g of pearlite, 20 g of anthracite (F.C58.3%), and 10 g of dolomite were mixed and the mixture was molded into a 10 mm diameter sphere to pellet (F.C11.39). %) Was prepared.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 5

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

It prepared in the same manner as in Example 4.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured by the same method as Example 2 above.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 6

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

It prepared in the same manner as in Example 4.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (industrial analysis method of coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 3.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 7

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30 g of water, 60 g of coal waste-rock (F.C 14.4%), and 40 g of red mud were mixed, and the mixture was molded into a 10 mm diameter sphere to prepare pellets (F. C 8.66%).

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 8

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

Carbon-containing pellets were prepared in the same manner as in Example 7.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured by the same method as Example 2 above.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 9

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

Carbon-containing pellets were prepared in the same manner as in Example 7.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 3.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 10

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30g of water, 60g of red mud, 30g of coal ash (F.C1.3%), and 10g of anthracite (F.C58.3%) were mixed to prepare pellets (F.C 6.02%) into a sphere having a diameter of 10 mm.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Example 11

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30 g of water, 60 g of red mud, 20 g of coal ash (F.C1.3%) and 20 g of anthracite (F.C58.3%) were mixed to prepare pellets (F.C 11%) into a sphere having a diameter of 10 mm.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Comparative Example 1

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30g of water, 60g of red mud, 10g of coal ash (F.C1.3%) and 30g of anthracite (F.C58.3%) were mixed to prepare pellets (F.C 16.2%) into a sphere having a diameter of 1 cm.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Comparative Example 2

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30 g of water, 60 g of coal ash (F.C1.3%), 20 g of pearlite, 6 g of anthracite (58.3% of fixed carbon (FC)), 14 g of dolomite were mixed, and the mixture was molded into a 10 mm diameter sphere and pellets ( Fixed carbon (FC) 4.01%) was prepared.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

Comparative Example 3

Vertical Autothermal Furnace Standard

The same vertical autothermal firing furnace as in Example 1 was used.

Carbon-containing Pellet Manufacturing

30 g of water, 60 g of coal ash (F.C 1.3%), 30 g of anthracite (58.3% of fixed carbon (FC)) and 10 g of dolomite are mixed, and the mixture is molded into a 10 mm diameter sphere to pellet (fixed carbon ( FC) 16.98%) were prepared.

Composition ratios of the pellets are shown in Table 1.

The fixed carbon content was measured by KS E 3705 (Industrial Analysis Method of Coal).

Manufacture of autothermal plastic

The autothermal fired body was manufactured in the same manner as in Example 1.

The firing furnace maximum limit temperature of the pellets is shown in Table 1.

The firing time of the autothermal fired body and the presence or absence of fusion between the pellets during firing were investigated and shown in Table 2.

[Test Example 1] collapse strength measurement

The collapse strength of the autothermal fired bodies of Examples and Comparative Examples was measured in the following manner.

When the formed pellets are processed in a certain shape and size, the change in strength suddenly changes, so select a self-heating plastic body with a diameter of 10 to 13 mm and press the pressure at a constant speed of 450 mm / min in one axis direction without any external processing. The maximum pressure at the moment of breaking was applied as the collapse strength. The instrument used for the crush strength was used by installing a load cell AFG2500N (Mecmesin. Ltd.) in a Versa Test.

The collapse strengths of the ten autothermal fired bodies of Examples 1 to 11 and Comparative Examples 1 to 3 were measured, respectively, and the average values were calculated and shown in Table 3 below.

Table 1. Pellet composition ratio and firing furnace maximum limit temperature in Examples and Comparative Examples

Table 2. Firing time of pellets of Examples and Comparative Examples and presence or absence of fusion of pellets during firing

Table 3. Crushing Strength of Examples and Comparative Examples

Claims (14)

1. A kiln in which the cross section is circular, elliptical or polygonal in a tapered shape with a lower portion than the upper portion, filled with carbon-containing pellets, and preheated to a predetermined temperature such that the filled pellets are autothermally fired;

   A pellet input unit configured to supply pellets to the upper part of the firing furnace into the firing furnace;

   A discharge part for discharging the self-fired pellets in the lower part of the firing furnace; And

   An air control unit provided at an upper portion of the kiln and configured to adjust an amount of air in the kiln;

   Vertical autothermal firing furnace comprising a.
2. The method of claim 1,

   A temperature sensor provided to measure a temperature in the firing furnace; And

   A water level sensor provided adjacent to the air conditioner and measuring a level of pellets filled in the firing furnace;

   Vertical autothermal firing furnace characterized in that it further comprises.
3. The method of claim 2,

   The temperature sensor is provided with at least one, vertical autothermal firing furnace, characterized in that capable of measuring the internal temperature of the kiln according to the height of the kiln.
4. The method of claim 1,

   The firing furnace is a vertical autothermal firing furnace having a tapered inclination angle of 2 ~ 30 °.
5. The method of claim 1,

   The discharge unit is a vertical self-firing kiln characterized in that the screw feeder or pin crusher for discharging a predetermined amount of the self-fired pellets.
6. The method of claim 1,

   The firing furnace is provided with a heater or the autothermal firing furnace, characterized in that preheating to a predetermined temperature using the heat of combustion of fossil fuel.
7. The method of claim 6,

   The heater is a vertical self-heating kiln provided in a belt shape in contact with the inner surface of the kiln.
8. The method of claim 1,

   The pellet input unit comprises a hopper for temporarily storing the pellet is supplied to the interior of the firing furnace and a feeder which is provided in the lower portion of the hopper to feed a predetermined amount of the pellet supplied into the firing furnace.
9. a) preheating by filling a pellet containing carbon in a vertical autothermal kiln according to any one of claims 1 to 8; And

   b) continuously inserting carbon-containing pellets into an interior of the kiln in which the preheated pellets are filled, and continuously discharging the carbon-containing pellets by autothermal firing of the pellets;

   Autothermal fired body manufacturing method comprising a.
10. The method of claim 9,

    The pellets have a carbon content of 4.5 to 15% by weight autothermal fired body manufacturing method characterized in that.
11. The method of claim 9,

    The pellet is a method for producing a autothermal fired body, characterized in that it contains 2 to 30% water.
12. The method of claim 11,

    The pellets are carbon-containing materials selected from coal waste-rock, coal and mixtures thereof, and red mud, dolomite, waste foundry sand, illite, pearlite, zeolite, diatomaceous earth, bentonite, vermiculite, manganese slag, clay, coal ash, fly ash, bottom ash and these Method for producing a autothermal fired body, characterized in that it comprises an inorganic material selected from the group consisting of a mixture of.
13. The method of claim 12,

    The pellet is a method for producing a autothermal fired body, characterized in that it is produced by molding into a spherical or oval shape of 5 ~ 30mm in diameter.
14. The method of claim 9,

    In step b), the pellets are fired by maintaining at 800 to 1300 ° C.

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