JP2000237528A - Method for using coal, coal dry distillation product and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize coal and to produce an adequate coal dry distillation product without the generation of dioxin by dry distilling coal, blowing the resulted coal dry distillation product into various process exhaust gases, recovering the coal dry distillation product in a dust collector and purifying the exhaust gases. SOLUTION: The coal is subjected to a dry distillation treatment in order to utilize the functionality of the carbonaceous material in the coal to carbonize the combustibles contained in the coal and to make the combustibles porous. The coal dry distillation product consisting of the coalified porous material is extremely high in the capability to adsorb hazardous substances, such as dioxin. Then, this coal dry distillation product is blown into the various process exhaust gases, by which the exhaust gases may be purified. As the coal is dry distilled, the chlorine-component contained therein may be removed. For example, the coat 6 is put into a quartz glass tube 1 and while this tube is heated by an electric heater 2, gaseous nitrogen 4 is supplied into the quartz glass tube 1 and the dry distilled exhaust gases 5 are discharged. Heating temperature is controlled by a temperature controller 7 via a thermocouple 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for using coal, a coal distillate suitable therefor, and a method for producing the same, and more particularly, to a method for efficiently using coal without generating dioxin. , And a suitable coal dry distillate obtained in the process, and a method for producing the same.

[0002]

2. Description of the Related Art Coal is used as a fuel for power generation and boiler because it is relatively inexpensive among fossil fuels. Further, since it is a solid fuel, it is widely used as a raw material for coke for iron making and a raw material for activated carbon. It's being used.

[0003] Coal is indispensable in the iron making process, and is used as a raw material for coke, which is a reducing agent in a blast furnace. Gas and tar by-produced in the process of coal dry distillation are also effectively used as fuel and chemical raw materials. Also,
Also in a sintering machine for agglomerating raw iron ore powder, coke powder after coal carbonization is used as a heat source. However, volatile matter contained in coke breeze has recently been pointed out as one of the causative substances of dioxin discharged from a sintering machine.

On the other hand, as an inexpensive DNX reduction method for removing dioxins in process exhaust gas, for example, waste incineration exhaust gas, many activated carbon injection methods have been reported.
It is also stipulated in the Ministry of Health and Welfare's guidelines for waste gas incineration. In Europe, on the background of abundant coal resources,
Blowing relatively inexpensive lignite dry matter into the exhaust gas of the sintering machine,
Technologies for reducing dioxin have been developed (literature;
Stahl und Eisen 117 (1997) Nr. 11, p49). According to this technique, the dry distillate (lignite coke) collected by the electric dust collector is reused as a heat source for sintering.

[0005]

However, it has recently become clear that volatile matter contained in coke breeze used as a heat source for a sintering machine and in the above-mentioned lignite coke is one of the substances causing dioxin formation. It has become. Also, in Japan, large quantities of inexpensive adsorbents such as lignite coke in Europe cannot be obtained, and therefore, activated carbon used in refuse incinerators is used in processes with large exhaust gas such as sintering machines. It is difficult to apply the blowing method.

[0006] The present invention has been made in view of such circumstances, and a method for effectively using coal without generating dioxin, a suitable coal carbonized product obtained in the process, and a method for producing the same. The task is to provide.

[0007]

The first means for solving the above problems is to carbonize coal, blow the obtained coal carbonized product into various process exhaust gases, and collect the coal carbonized product into a dust collecting device. A method for using coal (claim 1), wherein the exhaust gas is recovered and purified by exhaust gas.

[0008] In this means, the functionality of carbonaceous material in coal is utilized. That is, by subjecting the coal to dry distillation, the combustibles contained in the coal are carbonized to become porous and have a high specific surface area. this is,
This is because pores are formed by a dehydration reaction of volatile components contained in coal during the carbonization process. The carbonized porous coal distillate has an extremely high ability to adsorb harmful substances such as dioxin. Therefore, the exhaust gas can be purified by blowing the coal dry distillate into various process exhaust gases. Further, by carbonizing coal, the contained chlorine can be removed. Usually, since the carbonization process is performed in an inert atmosphere, the production of dioxins is also suppressed.

Further, according to the present means, it is possible to obtain an adsorbent for treating exhaust gas which is relatively cheaper than commercially available activated carbon. Therefore, it can be used by blowing a large amount into the exhaust gas of the sintering machine of the steel process.

[0010] A second means for solving the above-mentioned problems is as follows.
The recovered coal carbonized distillate is used as a heat source in various processes,
The present invention is characterized in that it is used as at least one of raw materials (claim 2).

The essence of this means is to use combustible components in coal in two stages (this is referred to as cascade use) to achieve more effective use. That is,
First, in the first stage, the exhaust gas is purified using the carbonaceous functionality as described above. In the second stage, the coal distillate adsorbing harmful substances is used as at least one of a heat source and a raw material in various processes. Since the amount of chlorine contained in the coal distillate is extremely small, even if the coal distillate is used as a heat source or a raw material, it does not cause generation of HCl or dioxins. Dioxin adsorbed on coal carbonized matter is decomposed by heat of combustion in various processes.

A third means for solving the above-mentioned problem is as follows.
The second means, wherein the process is a sintering machine in an iron making process (Claim 3).

[0013] As a use of coal dry distillate, it is particularly effective to use it as a heat source for a sintering machine in an iron making process.
This is due to the fact that the combustion temperature is about 1400 ° C at the maximum, the dioxin and its precursors to be introduced are almost decomposed, and the ash component is finally converted into slag (detoxification) in the blast furnace.

A fourth means for solving the above-mentioned problem is as follows.
A coal carbonized product obtained by carbonizing coal, wherein the volatile matter content is 1 wt.% Or less on a dry basis (claim 4).

In this means, the amount of volatile matter in the heat source, which is a substance causing dioxin formation, is set to 1 wt.% Or less. Therefore, in the method of use as in the first means to the third means, dioxin formation is prevented. It can be minimized.

A fifth means for solving the above-mentioned problem is as follows.
The ratio of the number of oxygen atoms / the number of carbon atoms in the coal used as raw material is 0.
A coal dry distillate characterized by satisfying at least one of a range of 05 to 0.2 and a ratio of (number of hydrogen atoms / number of carbon atoms) within a range of 0.6 to 1.0 (claim 5).

Coal having such a composition is characterized by having a high specific surface area by dry distillation, being hard to soften and melt in the dry distillation process, being relatively easily available, and having excellent storage stability. It is suitable for producing the coal dry distillate used in the first means to the third means.

A sixth means for solving the above-mentioned problem is as follows.
The fourth means or the fifth means, wherein the carbonization is performed at a carbonization temperature of 1000 ° C. or more (claim 6).

This means is particularly suitable when used as a raw material for a sintering machine. In other words, when used as a raw material for a sintering machine, as much as possible, it is desirable to remove volatiles in the distillate that is a causative substance of dioxin formation. Is preferred.

[0020] A seventh means for solving the above problem is as follows.
A method for producing a carbonized carbonized product, wherein a combustible gas generated in producing any of the fourth to sixth means is used as a heat source for carbonization or a process heat source in an ironworks. 7).

The combustible gas generated when carbonizing carbon is recyclable as a heat source for carbonization. Since this gas contains harmful substances such as chlorine, a device for removing these harmful substances is necessary for use. Further, a harmful substance removing device for exhaust gas from the carbonization device is also required. If the generated combustible gas is recycled and used as a heat source for carbonization, the harmful substance removing device for combustible gas can be omitted.

Further, this flammable gas can be used as a heat source in various iron making processes (blast furnace, coke oven, sintering oven, etc.). Since these steelmaking processes are provided with high-performance exhaust gas treatment equipment, there is no need to separately provide exhaust gas treatment equipment for removing harmful substances contained in combustible gas.

[0023]

Next, an embodiment of the present invention will be described in detail. Lignite, sub-bituminous coal, and bituminous coal can be used as the coal used as a raw material of the coal distillate in the present invention. Considering that it has a high specific surface area due to carbonization, it is difficult to soften and melt in the carbonization process in consideration of handling properties, and it has low reactivity and low spontaneous ignition in consideration of storability. It is preferable that the oxygen atom / carbon atom ratio is in the range of 0.05 to 0.2, the hydrogen atom / carbon atom ratio is in the range of 0.6 to 1.0, or both.

The particle size is not particularly limited, and varies depending on the method and process for carbonization. For example, 1mm for airflow layer
Or less, and 3 mm or more for a fixed floor. Although the ash content is not particularly specified, it is preferable that the ash content is small, since the carbon content in the carbonized matter increases, which is advantageous as an adsorbent and a fuel.

In a preferred embodiment of the present invention,
By using combustible components in coal in two stages (this is referred to as cascade use), more effective use is attempted. That is, in the first stage, the functionality of carbonaceous material is used. That is, by subjecting coal to dry distillation,
The contained combustibles utilize the property of becoming carbonized and porous, and are blown into exhaust gas of various processes such as a sintering machine to adsorb harmful components such as dioxin, SOx, and mercury. After utilizing the functionality of carbonaceous material, it is used as a heat source and raw material in various processes such as a sintering machine in the second stage,
More effective use of coal than before.

When used as a heat source, it is preferable that the amount of volatile components contained in the coal distillate is 1 wt.% Or less.
This is because volatile matter contained when the heat source burns becomes a substance causing dioxin production. The same effect can be obtained by setting the carbonization temperature to 1000 ° C. or higher.
Pitch, waste plastic, waste paper, etc. may be added to the coal as the third component. However, it is preferable that the added component does not soften and melt.

The dry distillation is performed in an inert atmosphere. By treating in an inert atmosphere, combustion of carbonaceous material is suppressed. As a result, the yield of the distillate and the ratio of carbonaceous matter in the distillate can be increased, and the generation of dioxin can be suppressed. Further, the carbonization may be performed in the presence of steam or oxygen. By treating in the presence of steam or oxygen, it is possible to increase the specific surface area of carbonaceous material and to increase the pore diameter. At this time, it should be noted that if the oxygen partial pressure is too high, carbonaceous combustion occurs.

As the carbonization furnace, a general industrial furnace can be used. For example, a rotary kiln, a fluidized-bed furnace, a coke oven, or the like may be used. A gas bed thermal decomposition furnace may be used. The carbonization temperature may be about 600 ° C. for producing the adsorbent, but is preferably 1000 ° C. or more when it is used as a heat source for sintering. If the temperature is lower than 400 ° C., the specific surface area and adsorption performance required for the adsorbent cannot be obtained. In addition, there is a possibility of operation trouble due to melting of some ash components, so the carbonization temperature is 1300
It is preferable that the temperature is set to not more than ° C. The carbonization temperature here is
This is the temperature of the raw coal. The carbonization time depends on the carbonization temperature, but when used as a heat source for sintering, a residence time of 30 minutes or more is preferable.

The obtained dry distillation product may be further subjected to an activation treatment with steam, oxygen, or the like. This treatment can be expected to increase the specific surface area and pore size of the carbonized product. However, when the ash content in the carbonized matter is high, attention must be paid to the fact that the specific surface area may be reduced due to the consumption of carbonaceous material.

The obtained dry distillate may be directly blown into exhaust gas from a sintering machine or the like, but it is preferable to carry out a pulverization treatment if necessary. By pulverizing, an increase in specific surface area and an improvement in dispersibility in exhaust gas can be expected. Grinding particle size is 5mm
Or less, preferably 1 mm or less. Considering the crushing process,
Generally, it is sufficient that the above-mentioned particle size component is contained in a certain ratio. For example, the pulverization may be carried out so as to contain a particle size component of 0.8 mm or less in a weight ratio of 80% or more. Further, it is also possible to remove ash simultaneously or after crushing by specific gravity separation or the like. Thus, an increase in the specific surface area of the adsorbent per weight can be expected.

The process exhaust gas into which the obtained carbonized material is blown is not limited to a sintering machine, but may be from a refuse incinerator, a power plant, a steelmaking electric furnace, a scrap melting furnace, or the like. The blowing of the obtained dry distillation is mainly performed to remove dioxins, SOx, and mercury contained in the exhaust gas. The blowing is performed in the exhaust gas before the dust collector. The adsorbent may be blown by a general solid blowing nozzle, and is conveyed and blown together with an air current such as air or nitrogen. The amount of adsorbent injected depends on the type of exhaust gas,
In general, the blowing amount in terms of the mass of carbon in the adsorbent per 1 Nm ³ of exhaust gas is about 0.01 to 0.5 g / Nm ³ , preferably 0.1 to 0.3 g / Nm ³ . Here, the carbon mass is a value excluding ash in the adsorbent. The ash content here is a value measured by JIS M8812.

The dust collector used may be a bag filter or an electric dust collector. The temperature of the exhaust gas when collecting dust is 200 ° C or lower, preferably 150 ° C or lower. This is because if the temperature is 200 ° C. or higher, the dioxin removal effect is significantly reduced, and in some cases, dioxin may be resynthesized and increased.

The dry matter collected by the dust collector can be used as a substitute for pulverized coal for blast furnaces, as a fuel for power generation, a raw fuel for cement, and a fuel for boilers. Chlorine, which is a volatile impurity, has been mostly removed by dry distillation in advance, so that it can be used as a raw material for cement. However, it is necessary to completely burn when using combustion like fuel for boilers.
If the combustion is not complete, there is a possibility of dioxin generation, and it is necessary to separately treat exhaust gas.

As a use as a solid fuel, it is particularly effective to use it as a heat source for a sintering machine in an iron making process. This is due to the fact that the combustion temperature is about 1400 ° C at the maximum, the dioxin and its precursors to be introduced are almost decomposed, and the ash component is finally converted into slag (detoxification) in the blast furnace.

Further, the flammable gas generated at the time of carbonization can be preferably used as a heat source for carbonization or a process heat source in a steelworks. Heat sources in steelworks are used in blast furnaces, coke ovens, metal heating ovens, heat treatment ovens and incinerators. In particular, mixing with the dry distillation gas of a coke oven is preferable because special equipment for tar treatment and gas treatment is not required.

As described above, according to the present invention, an adsorbent for exhaust gas treatment can be obtained relatively inexpensively compared with commercially available activated carbon, and the activated carbon injection method can be applied to the sintering process in Japan. . Furthermore, coal can be effectively used by reusing it as a heat source. Further, by reducing the amount of volatile components in the heat source, which is a substance causing dioxin generation, to 1 wt.% Or less, it becomes possible to minimize the generation of dioxin.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. (Example 1) Properties of the coal A used are shown in Table 1. In Table 1, volatile matter, fixed carbon, and ash are on a dry basis, and carbon, hydrogen, and oxygen show values on a dry and ash-free basis. This coal was carbonized in the electric tubular furnace shown in FIG. In FIG. 1, 1 is a quartz glass tube, 2 is an electric heater, 3 is a thermocouple, 4 is a nitrogen gas, 5 is a carbonized exhaust gas, 6 is coal, and 7 is a temperature controller. Coal 6 was put into electric heater 2, nitrogen gas 4 was supplied at a rate of 50 ml / min, and the temperature was raised to 1000 ° C. at a heating rate of 10 ° C./min. The temperature was measured by a thermocouple 3 and controlled by a temperature controller 7. The yield of the obtained dry distillate is 58.2%, JIS M 88
Ash and volatiles measured by 12 are 51.9db each
% And 0.5 db%. The specific surface area measured by the BET method was 268 m ² / g.

(Example 2) The properties of the coal B used are shown in Table 1. A carbonized product was obtained in exactly the same manner as in Example 1 except that the coal used was different and the carbonization temperature was 1100 ° C.
The yield of the obtained dry distillate is 56.0%, and the ash content and volatile content measured by JIS M 8812 are 7.9db% and 0.3db%, respectively.
Met. The specific surface area measured by the BET method is 32.
8 m ² / g.

(Example 3) The properties of the coal C used are shown in Table 1. A dry distillate was obtained in exactly the same manner as in Example 1 except that the coal used was different. The yield of the obtained dry matter is
The ash content and volatile content measured by 50.7% and JIS M 8812 were 20.3db% and 0.2db &, respectively. In addition, BET
The specific surface area measured by the method was 268 m ² / g.

(Example 4) The properties of the coal D used are shown in Table 1. The coal was carbonized in an externally heated rotary kiln furnace. The furnace was kept in a nitrogen atmosphere and the temperature was kept at 1050 ° C. Coal was charged at a rate of 10 kg / hour from the furnace charging section, and the residence time was set at 30 minutes to carry out dry distillation. The yield of the obtained dry matter is 6
The ash content and the volatile content measured by 5.3% and JIS M 8812 were 18.4db% and 0.3db%, respectively. In addition, BET
The specific surface area measured by the method was 309 m ² / g.

(Example 5) The properties of the coal A used are shown in Table 1. Dry distillation was performed in the same manner as in Example 4 except that the coal used was different. The yield of the obtained dry matter is
The ash content and the volatile content measured by 55.6% and JIS M 8812 were 52.3db% and 0.4db%, respectively. In addition, BET
The specific surface area measured by the method was 278 m ² / g.

Example 6 A carbonized product was obtained in exactly the same manner as in Example 1 except that the carbonization temperature was 600 ° C. The yield of the obtained dry distillate was 68.2%, and the ash content and volatile content measured by JIS M 8812 were 47.1 db% and 10.6 db%, respectively. The specific surface area measured by the BET method is 226 m ² / g
Met.

(Example 7) Except that the dry distillation temperature was 800 ° C
A dry distillate was obtained in exactly the same manner as in Example 2. The resulting dried
The yield of dirt is 61.2%, ash content measured by JIS M 8812
And the volatile components were 8.0% and 6.3d.b.%, respectively. Ma
The specific surface area measured by the BET method was 330 m ^Two/ g
Was.

Example 8 A carbonized product was obtained in exactly the same manner as in Example 3 except that the carbonization temperature was 900 ° C. The yield of the obtained dry distillate was 58.0%, and the ash content and volatile content measured by JIS M 8812 were 19.3 db% and 5.3 db%, respectively. The specific surface area measured by the BET method is 276 m ² / g
Met.

[0045]

[Table 1]

The performance of the adsorbent obtained in each example was evaluated using a test apparatus shown in FIG. In FIG. 2, 8
Is the exhaust gas flue of the sintering machine, 9 is the flow direction of the exhaust gas of the sintering machine,
10 is a heat exchanger, 11 is an adsorbent hopper, 12 is an adsorbent blowing port, 13 is a bag filter, 14 is a blower,
Reference numerals 15 and 16 are exhaust gas sampling ports.

The actual exhaust gas was sucked from the exhaust gas flue 8 of the sintering machine in the iron making process by the blower 14, and the temperature of the exhaust gas was adjusted to 200 ° C. by the heat exchanger 10. Coal dry distillate stored in the adsorbent hopper 11 was quantitatively cut out from the adsorbent injection port 12 and approximately 0.5 g (equivalent to 0.25 g / Nm3 in terms of carbonaceous material) was blown per 1 Nm3 of exhaust gas. . The dust originally present in the exhaust gas and the carbonized charcoal blown were collected by the bag filter 13.
The dioxin concentration in the exhaust gas collected from the exhaust gas sampling port 16 was measured twice and averaged. The dioxin concentration in the exhaust gas collected from the sampling port 16 is as shown in Table 2 in the case of the adsorbent in each example, when the value in the case where coke breeze dust (volatile content: 2.1%) is used as the adsorbent is 100. Value.

The term "dioxin" used here means Polyoxin.
chloro dibenzo-p-dioxin, Poly chloro dibenzo-fura
It is a generic term for n, and the dioxin concentration means an actual concentration, not a toxicity conversion value. In Examples 6 to 9, the reason why good results were not obtained as compared with coke breeze is considered to be because the carbonization temperature was 1000 ° C or lower.

[0049]

[Table 2]

Further, in Example 5, when the dioxin concentration in the exhaust gas collected from the collection port 15 was 100, the dioxin concentration in the exhaust gas collected from the collection port 16 was 12.

Next, in each embodiment, the bag filter 1
Fig. 3 shows whether the dust and coal distillate recovered in step 3 can be used in place of coke breeze as a heat source in a sintering machine.
The evaluation was performed using a sintering test apparatus shown in FIG. In FIG. 3, 17 is an ignition furnace, 18 is an ignition burner, 19 is a pot, and 20 is a wind box. The sample is put in the pan 19 and ignited by the ignition burner of the ignition furnace 17. A wind box 20 is provided below the pan 19, from which air is sucked to the outside. With these devices, the sample is sintered through a process similar to that for producing a sintered ore.

The recovered adsorbent (coal distillate) was used in place of coke breeze for sintering with a calorific equivalent. As a result, the product characteristics of the obtained sintered ore were almost equal to those obtained by using coke breeze as a heat source even when almost 100% substitution was performed.

[0053]

As described above, in the present invention according to the first aspect of the present invention, the exhaust gas can be purified by injecting the coal distillate into various process exhaust gases. Further, by carbonizing coal, the contained chlorine can be removed.

According to the second aspect of the present invention, more effective use can be achieved by using the combustible components in the coal in two stages.

According to the third aspect of the present invention, the coal distillate is used as a heat source for the sintering machine, so that the dioxin and its precursor can be substantially decomposed, and the ash component can be reduced to the final amount. It can be made slag (detoxified) in a blast furnace.

According to the fourth aspect of the present invention, since the amount of volatile matter in the heat source, which is a substance causing the generation of dioxin, is set to 1 wt.% Or less, it is possible to minimize the generation of dioxin.

In the invention according to claim 5, the ratio of (number of oxygen atoms / number of carbon atoms) is in the range of 0.05 to 0.2.
Since coal is used as a raw material that satisfies at least one of the ratio of (number of hydrogen atoms / number of carbon atoms) in the range of 0.6 to 1.0, a dry fraction having a high specific surface area can be obtained, and softening and melting during the dry distillation process In addition, it is possible to use raw materials which are difficult to obtain, are relatively easily available, and have excellent storage stability.

In the invention according to the sixth aspect, since the carbonization is performed at a carbonization temperature of 1000 ° C. or more, the volatile matter in the carbonized material is reduced, which is particularly suitable when used as a raw material for a sintering machine. Becomes

In the invention according to claim 7, since the combustible gas generated is used as a heat source for dry distillation or a process heat source in an ironworks, a separate exhaust gas treatment facility for removing harmful substances contained in the combustible gas is used. No need to provide.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an electric furnace for carbonizing RDF.

FIG. 2 is a diagram showing how an adsorbent performance evaluation tester evaluates the adsorptivity of harmful substances in the exhaust gas of a sintering machine in an iron making process.

FIG. 3 is a schematic diagram showing a test device for evaluating the adsorbent substitute performance of adsorbent in a sintering machine.

[Explanation of symbols]

1. Quartz glass tube, 2. Electric heater, 3. Thermocouple, 4.
... nitrogen gas, 5 ... dry distillation exhaust gas, 6 ... coal, 7 ... temperature controller, 8 ... flue gas of sintering machine, 9 ... flow direction of sintering machine exhaust gas, 10 ... heat exchanger, 11 ... adsorbent hopper , 12 ...
Adsorbent injection port, 13: bag filter, 14: blower, 15, 16: exhaust gas sampling port, 17: ignition furnace, 18: ignition burner, 19: pot, 20: wind box

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Tatsuro Ariyama 1-2-2 Marunouchi, Chiyoda-ku, Tokyo F-term in Nihon Kokan Co., Ltd. 4D002 AA19 AA21 AC02 AC10 BA04 BA14 CA01 DA41 GA01 GA02 GA03 GB01 GB02 GB03 GB06 GB08 GB11 GB12 HA08 4H012 GB06 LA02 LA05

Claims (7)

[Claims] 1. A method of using coal, comprising: coal-distilling coal; blowing the obtained coal-distilled matter into various kinds of process exhaust gas; purifying the exhaust gas by collecting the coal-distilled substance by a dust collector; . 2. The method for using coal according to claim 1, wherein the recovered coal dry distillate is used as at least one of a heat source and a raw material in various processes. 3. The method according to claim 2, wherein the process is a sintering machine in an iron making process. 4. A coal carbonized product obtained by carbonizing coal, wherein the volatile matter content is 1% by weight or less on a dry basis. 5. The raw material coal has a (oxygen atom / carbon atom) ratio in the range of 0.05 to 0.2, and a (hydrogen atom / carbon atom) ratio in the range of 0.6 to 1.0. A coal distillate characterized by satisfying at least one of the following. 6. The carbonized carbonized product according to claim 4, wherein the carbonized carbonized product is carbonized at a carbonization temperature of 1000 ° C. or higher. 7. One of claims 4 to 6
A method for producing a carbonized carbonized product, comprising using a flammable gas generated when producing the carbonized carbonized product described in the above section as a heat source for carbonization or a process heat source in an ironworks.