JPH10237511A - Operation of blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the utilizing of treating material as fuel without sorting the treating material containing combustible municipal waste by reacting harmful chlorine base gas which is generated by heating the treating material containing chlorine component, with dechlorinating agent, making this chlorine base gas harmless and blowing this treated material into a blast furnace as auxiliary fuel. SOLUTION: A tank 20 filling up the treating material and the dechlorinating agent composed of a carbonate based alkali material and closed with a closing cover 21, is inserted in a heating source 22 and heated under low oxygen atmosphere at the decomposed temp. or higher of the chlorine component, and the decomposed harmful chlorine base gas and the dechlorinating agent are acted to generate NaCl, H2 O and CO2 gas. After this dry-distillation treatment, the tank 20 is taken out from the heating source 22 and cooled, and after exhausting gas in the tank, the remained slag (treated ash) in the tank is taken out. The exhaustion of the gas is executed by closing a valve 28 and opening a valve 24 and a valve 27 and driving a pump 25, mixing it with pulverizing fine coal from a hopper 7 to directly supply the mixture into a blast furnace 14, or the gas is temporarily stored in a tank 29 and supplied to the blast furnace 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating a blast furnace, and more particularly to a method for heating an object to be treated, such as waste containing chlorine components such as chlorine and chlorine compounds, to remove harmful chlorine gas generated at this time. The present invention relates to a method for operating a blast furnace, wherein the blast furnace is made harmless by reacting with a dechlorinating agent, and is blown as auxiliary fuel from a tuyere of the blast furnace to be used as fuel.

[0002]

2. Description of the Related Art Conventionally, in a blast furnace, as an auxiliary fuel for coke, heavy oil or pulverized coal has been blown from a tuyere of the furnace to produce pig iron or the like.

[0003] In recent years, as this auxiliary fuel, synthetic resin waste (waste) such as plastic has been pulverized into granular or powdery form and injected into heavy oil, or directly blown into a tuyere to treat municipal waste. Technologies for effective use of resources have been developed. (Example: JP-A-7-228905, JP-B-51-33493) FIG. 2 is a conceptual diagram showing a method of operating a blast furnace using this plastic waste as an auxiliary fuel for pulverized coal. The plastic waste as a raw material is put into the receiving hopper 1, where drying is also performed to remove moisture. This receiving hopper part 1
The plastic waste supplied from is crushed in the crushing unit 2,
In the sieving section 3 in the next step, the particles are sieved to a preset particle size, and the particles having the set particle size are sent to the plastic powder supply hopper 4 and stored. Particles larger than the set particle size are returned from the sieving unit 3 to the crushing unit 2 again, and crushed again. The plastic powder stored in the supply hopper 4 is sent to the transport pipe 6 via the flow rate adjusting unit 5.

On the other hand, pulverized coal is stored in a hopper 7 for pulverized coal, and is sent to a transport pipe 6 via a flow rate adjusting unit 8. The carrier air is supplied to the carrier pipe 6 from the pneumatic pressure source 9 at a predetermined air volume and speed, and the plastic powder is mixed with the pulverized coal and the powder is distributed to each tuyere by the powder distributor 10. Then, a plurality of nozzles 13 inserted into the blast furnace air blow pipe 12 through the transfer pipe 11 are blown into the blast furnace 14 at high speed through tuyeres 15 provided in the blast furnace 14, and are burned in the combustion zone of the blast furnace. .

[0005]

In order to supply a synthetic resin to a blast furnace as an auxiliary fuel, as a pre-treatment, the synthetic resin is separated from waste and pulverized so that air can be conveyed. It is necessary to process it so that it can be blown from the mouth. For example, it is necessary to pulverize and granulate to a granular form (0.5 to 5 mm) or a powder form (less than 5 mm), and the processing requires a large-scale machine and the work is complicated.

Since the temperature of the tuyere is considerably high, the fine synthetic resin may melt and block the tuyere. In order to prevent this, it is necessary to supply at a considerably high pressure and at a high speed, and a very large supply means is required.

[0007] On the other hand, in the case of effectively utilizing garbage such as municipal waste, the to-be-treated material such as municipal garbage is generally discharged not only from industrial waste but also from general households and offices. However, there is a problem that it is troublesome because it is necessary to select a synthetic resin such as a plastic from these.

Accordingly, an object of the present invention is to provide a technique in which an object to be treated containing combustible municipal waste other than plastic is heated without being sorted, and a gas generated at this time can be used as an auxiliary fuel for a blast furnace. It is assumed that.

[0009]

In general, municipal garbage is discharged as an object to be treated from general households or offices, and is mainly combustible. This combustible material contains a large variety of chemical substances, for example, a large amount of chlorine components such as chlorine bleach for plastics containing a large amount of vinyl chloride resin and paper used in offices. The substance is mixed.

Therefore, it is impossible to incinerate these objects as they are and to use the combustion gas generated during the incineration as fuel for the blast furnace.

As a method of dechlorinating the combustion gas generated during the heat treatment, the generated gas is treated by various means.
For example, although emphasis is placed on cleaning treatment such as adsorption treatment with a filter or the like, it is difficult to completely remove it.

The inventors of the present application have found that, as a result of various experiments and investigations, when degassing a gas generated by thermally treating an object containing a large amount of chlorine components, a chlorine-based gas (hydrogen chloride gas) is used. , Chlorine gas), which were reacted with each other by adding a carbonic acid-based alkali substance as an additive, and the harmful chlorine-based gas was replaced with harmless chloride.

The present invention has been made based on this finding, and is made of a carbonate-based alkali substance that reacts in a heated low-oxygen atmosphere with harmful chlorine-based gas generated during heat treatment of wastes and the like. By adding a dechlorinating agent and reacting with the chlorine-based gas to generate harmless chlorides, the harmful chlorine-based gas in the gas is removed to obtain a harmless gas. It is characterized by being blown from the mouth.

Here, the low oxygen atmosphere means that the oxygen component is small.

That is, in the case of a heat treatment furnace, a state in which the non-processed material is charged and the atmosphere remains inside with the inlet and outlet closed is allowed.

The closure need not be completely closed,
Even if the inlet side is closed by the object to be treated, the pressure inside the furnace has increased due to heating, etc.
Almost no intrusion of outside air is allowed. Generally speaking, it is equivalent to "carbonization".

On the other hand, after the heat treatment (either in the case where the dechlorinating agent of the present invention is supplied and treated, or in the case where the treatment is performed without supplying the dechlorinating agent), an arbitrary portion up to the discharge in a low oxygen atmosphere is discharged. Detoxification treatment can be performed by supplying to exhaust gas or residue.

The material to be treated may be any of waste (solid matter) containing a chlorine component, sludge, gas (exhaust gas, dry distillation gas), and the like.

As the dechlorinating agent used in the present invention, (1) a substance selected from a mixture of a simple substance of a carbonate-based alkali substance, two or more simple substances, and two or more simple substances.

(2) Carbonic acid-based sodium substance (3) A substance selected from sodium hydrogen carbonate, sodium carbonate, sodium sesquicarbonate, a simple substance selected from natural soda, two or more simple substances, and a mixture of two or more simple substances.

It is used by appropriately selecting from the following.

The shape of the dechlorinating agent may be any of a lump, a plate, a porous shape, and a powder (powder, granule or a mixture thereof). Use in combination.

When the object to be treated is a solid or liquid, it is reacted with a gas generated by mixing or charging the solid or liquid.

In the case of a gas such as exhaust gas, the gas is reacted by spraying, or the gas is contacted and passed through a filter to be reacted.

In addition, the form of addition is solid (lump, powder),
A liquid (aqueous solution, other solution, suspension) or a combination thereof is used to react with generated gas.

The amount of the dechlorinating agent used is preferably 0.05 to 10% by weight based on the starting weight of the material to be treated, but the material to be treated may be vinyl chloride, vinylidene chloride, synthetic resin, rubber,
When chloride is contained in a large amount as in the case of, for example, 10 to 70% by weight of the starting weight is added. Alternatively, it is added in the same amount or more as the amount of chlorine-based gas generated from the object to be treated regardless of the weight. Alternatively, the amount to be added is selected so as to be below the allowable emission standard for chlorine-based gas and the like.

The dechlorinating agent may be added at a temperature below the thermal decomposition temperature of the chlorine component (mixed from the beginning), during thermal decomposition (spraying during heating), or after thermal decomposition (dry distillation gas, exhaust gas). Or the combination is appropriately added. This thermal decomposition means may be either dry distillation or incineration or a combination thereof. The heat treatment temperature is the decomposition temperature of the chlorine component (200 ° C.).
To 300 ° C) to 1000 ° C.

When a heat treatment is performed by adding a dechlorinating agent to the treated product under the above conditions, for example, when sodium hydrogen carbonate (NaHCO ₃ ) is added, hydrogen chloride (HC
l) reacts with:

(NaHCO ₃ ) + (HCl) → (NaC
l) + (H ₂ O) + (CO ₂ ) From this, if there are Na and CO components, the chlorine component becomes
It becomes NaCl, water (H ₂ O), and gaseous CO _{2 as} a part of the residue, does not generate hydrogen chloride which is a cause of dioxin, and can realize harmlessness of the exhaust gas and the residue.

Therefore, even when used as a fuel in a blast furnace,
It does not cause air pollution by itself and can be used effectively.

[0031]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a conceptual diagram for explaining a method of operating a blast furnace according to the present invention. Note that the present invention is characterized by applying a waste treatment system instead of the conventional plastic waste supply system, and other blast furnaces and pulverized coal supply to the blast furnace are almost the same. The same reference numerals as those in 2 denote the same or corresponding parts, and a detailed description thereof will be omitted.

In FIG. 1, reference numeral 20 denotes a tank, which is made of, for example, an iron-based material (preferably a magnetic material) and has an openable / closable lid 21. Reference numeral 22 denotes a heating source, which is formed in a cylindrical shape such as a cylinder or a square tube.
Is inserted. Then, the tank 20 is heated by supplying electric power to the heating source 22. 23 is an exhaust pipe with a valve, 24 is a valve, 25 is a pump, and 26 is a gas amount adjusting means.

Reference numeral 22 'denotes a heating source provided on the bottom surface side of the tank 20, which is appropriately installed according to the size of the tank, the amount of the object to be processed, and the like.

Reference numerals 27 and 28 denote valves, and reference numeral 29 denotes a gas storage tank.

The objects to be heated are waste, sludge,
Although any substance containing a chlorine component such as exhaust gas may be used, an example in the case of a general treatment (dust) treatment will be described.

In the heat treatment of the object to be treated, the object to be treated and a dechlorinating agent are filled in a tank, sealed with a sealing lid to shut off the outside air, and this tank is inserted into a heating source 22 installed in advance. Then, electric power is supplied to the heating source to heat the entire tank, and the workpiece is subjected to dry distillation. After the heat treatment for a predetermined time, the tank is taken out of the heating source and cooled, and after the gas in the tank is extracted, the residue (processed ash) in the tank is removed.
Take out.

When the gas is extracted directly from the pulverized coal hopper 7, the gas is mixed with the pulverized coal from the pulverized coal hopper 7 by closing the valve 28, opening the valves 24 and 27, and operating the pump 25 when supplying directly to the blast furnace as auxiliary fuel. , A feed pipe 11, a nozzle 13, and a blast furnace air pipe 12 to supply the blast furnace 14 from the tuyere 15.

The gas may be supplied to the transfer pipe 11 through a gas supply pipe 30 indicated by a two-dot chain line.

When the gas is temporarily stored in the gas storage tank 29, the valve 27 is closed, the valves 24 and 28 are opened, the pump 25 is operated, the gas is stored in the storage tank 19, and the valve is appropriately operated after the storage. (Opened 27 and 28) to supply as auxiliary fuel in the same manner as above.

The gas may be extracted from the tank by immediately extracting the tank from the heating source and then immediately cooling it, or by cooling it while heating it with the heating source. In this example, the case where the heating source is electric heating is described, but any of gas heating, induction heating, combustion heating, or microwave heating may be used,
In addition, the means for pyrolysis of chlorine components is either dry distillation or incineration,
Alternatively, a combination thereof may be used.

As the dechlorinating agent to be mixed into the object to be treated, a carbonate-based alkali substance is used as described later. The dechlorinating agent and the object to be treated are charged into the tank 20, and electric power is supplied to the heating source 22 (22 ') for heating. When the temperature exceeds the decomposition temperature (200 ° C. to 300 ° C.) of the chlorine component, the chlorine component is decomposed, and the decomposed chlorine-based gas reacts with a dechlorinating agent composed of a carbonic acid-based alkali substance. Contains no harmful chlorine gas. This gas is blown from the tuyere 15 of the blast furnace 14 as auxiliary fuel.

The following experimental investigation revealed that the carbonic acid-based alkali substance replaces harmful chlorine-based gas in the exhaust gas with harmless chloride.

In the experiment, first, polyvinylidene chloride containing a large amount of a chlorine component was used, and samples shown in Table 1 were prepared.
When 20 g of sodium bicarbonate was added to 4 g of polyvinylidene chloride (Example 1), when no additive was added (Comparative Example 1), and when 20 g of slaked lime was used as an additive (Comparative Example 1), Calcium carbonate 2
A comparative experiment was performed when 0 g was used (Comparative Example 3).

[0045]

[Table 1]

As a result of the experiment, as shown in Table 3, good results were obtained when sodium hydrogen carbonate was added.

Therefore, a simulated garbage simulating the following standard municipal garbage was prepared, and polyvinylidene chloride was added to create a more severe situation, and the amount was changed. Example 2, Example 3, Example 4,
An experiment (additional test) for practical use of Example 5 was performed. Also,
In addition, the effect of moisture was also investigated.

The dechlorinating agent used was a powder having an average particle size of 100 μm.

Simulated garbage 20% by weight Plastic (PE, PP, PS, PVDC) 50% by weight Paper (tissue, newspaper, wrapping paper, box, drink pack) 20% by weight Cloth (waste, etc.) 10% by weight・ Crushed garbage

[0050]

[Table 2]

In the experiment, the sample was placed in a closed vessel equipped with an exhaust pipe, heated in an electric furnace, and heated from 250 ° C. to 600 ° C.
The temperature was maintained at each temperature for 5 minutes at intervals of ° C, and the concentration (ppm) of hydrogen chloride gas (HCl) was measured at the time of temperature rise and at the time of keeping.

The gas concentration was measured using a detector tube specified in JIS-K0804.

Table 3 shows the measurement results. The hydrogen chloride gas concentration is a value measured in 10 experiments and is shown in Examples 1 to 5.
Indicates the highest value, and Comparative Examples 1 to 3 indicate the lowest values.

Note that "ND" indicates "not detected" and 1
It shows that none was detected in 0 experiments.

[0055]

[Table 3]

First, a preliminary experiment was conducted using only polyvinylidene chloride containing a large amount of a chlorine component.
The results are shown in Comparative Example 1 in Table 3.

Next, an experiment was conducted by adding a conventionally known powder of slaked lime and calcium carbonate as a dechlorinating agent.
The results are shown in Comparative Examples 2 and 3.

Therefore, as a result of various studies and deliberation, an experiment was conducted by selecting sodium bicarbonate, focusing on a carbonate-based alkaline substance. The results are shown in Example 1.

Subsequently, an experiment was conducted using simulated garbage simulating the above-mentioned standard municipal garbage and changing the amounts of polyvinylidene chloride and sodium hydrogen carbonate. The results are shown in Examples 2, 3, and 4.

Further, water was added to the simulated garbage, and the influence of the water was examined. The results are shown in Example 5.

From the results shown in Table 3, the following is considered. First, when polyvinylidene chloride containing a large amount of a chlorine component is used as an object to be treated, a large amount of hydrogen chloride gas is generated over each temperature for heat treatment in Comparative Example 1 in which a dechlorinating agent is not added. In Comparative Example 2 in which slaked lime as a conventional dechlorinating agent was added to the object to be treated, and in Comparative Example 3 in which calcium carbonate was added as a dechlorinating agent, generation of hydrogen chloride gas was considerably suppressed as compared with Comparative Example 1. But still not enough.

On the other hand, in Example 1 in which sodium bicarbonate powder was added as a dechlorinating agent to the above-mentioned object, hydrogen chloride gas was not detected over the entire temperature range, and extremely good results were obtained. . Further, in the cases of Examples 2, 3, and 4 in which the amount of sodium bicarbonate added as a dechlorinating agent was changed with respect to the object to be treated in which polyvinylidene chloride was added to the simulated garbage, over the entire temperature range. No hydrogen chloride gas was detected.

Example 5 in which sodium bicarbonate powder was added to an object to be simulated by adding water to the simulated waste.
In the case of, slight generation of hydrogen chloride gas was observed when the temperature was raised and kept at 450 ° C, and when the temperature was raised to 500 ° C. It was not affected and very good results were obtained as compared to Comparative Example 2 using slaked lime as a dechlorinating agent.

According to the above experimental investigation, when a substance containing a chlorine component is dechlorinated by thermal treatment, a carbonate-based alkali substance (particularly, a sodium-based substance) reacting with a chlorine-based gas is added as an additive. It was confirmed that harmless treatment could be achieved by the treatment.

Although the same effect was obtained at a temperature of 600 ° C. or higher, the maximum temperature is preferably 1000 ° C. in consideration of the fact that the equipment becomes large at high temperatures.

When a carbonic acid-based alkali substance, in particular, a sodium-based substance reacts with a chlorine-based gas, detoxification of exhaust gas and residues can be realized because the harmful chlorine-based gas is replaced with harmless chloride as follows. Will be generated.

(1) In the case of sodium hydrogen carbonate When sodium hydrogen carbonate (NaHCO ₃ ) is added, it reacts with aqueous chloride (HCl) to give the following.

(NaHCO ₃ ) + (HCl) → (NaC
l) + (H ₂ 0) + (CO ₂ ) When water is present (NaHCO ₃ ) + (H ₂ O) → (NaOH) + (H ₂ C)
O ₃ ) (NaOH) + (H ₂ CO ₃ ) + (HCl) → (NaC
1) + (H ₂ O) + (CO ₂ ).

(2) In the case of sodium carbonate When sodium carbonate (Na ₂ CO ₃ ) is added, it reacts with hydrogen chloride (HCl) to give the following.

(Na ₂ CO ₃ ) + (2HCl) → (2Na
Cl) + (H ₂ O) + (CO ₂ ) (3) In the case of sodium sexquicarbonate represented by the chemical formula Na ₂ CO ₃ .NaHCO ₃ .2H ₂ O, the same reaction as in the above (1) and (2) Then, harmful hydrogen chloride (HCl) is replaced with harmless chloride (NaCl) to generate.

When the obtained residue was analyzed, no harmful chlorine-based gas components were detected, and harmless chloride, sodium chloride (NaCl), was detected. In addition, the residue
By washing with water while stirring for 0 minute, sodium chloride was dissolved in water, and a carbide remained, but no chlorine-based gas component was detected in the carbide.

Accordingly, the chlorine component becomes N as a part of the residue.
It becomes aCl, water (H ₂ O) and gaseous CO ₂ , does not generate hydrogen chloride which is a cause of dioxin, and can realize harmlessness of exhaust gas and residue.

From the above, as the dechlorinating agent, the following substances showing the same reaction as described above can be used.

(1) A mixture selected from a simple substance of a carbonate-based alkali substance, two or more simple substances, and a mixture of two or more simple substances.

(2) Carbonic acid-based sodium substance (3) A substance selected from a simple substance selected from sodium bicarbonate, sodium carbonate, sodium sesquicarbonate and natural soda, a mixture of two or more simple substances, and a mixture of two or more simple substances .

Note that sodium hydrogen carbonate (NaHC)
O ₃ ) is also referred to as (a) sodium acid carbonate (b) sodium bicarbonate (c) sodium bicarbonate, and is also commonly referred to as baking soda.

Sodium carbonate (Na ₂ CO ₃ ) is also called sodium carbonate or simply soda as another name, and anhydrous salt is also called soda ash, and decahydrate is also called washing soda or crystal soda. .

Sodium sequicarbonate (Na ₂ CO ₃ .Na
HCO ₃ .2H ₂ O) is also referred to as (a) sodium monocarbonate bicarbonate (b) sodium bicarbonate (c) sodium sesquicarbonate, and is naturally produced as trona (natural soda).

On the other hand, NaCl is produced by the reaction, and the produced NaCl is a harmless chloride.
Cl can be effectively removed by a washing treatment with a solution such as water, and after washing, a reusable carbonized substance remains.

Therefore, depending on the characteristics of the residue, the residue can be separated into various substances by a separation means or the like, and the separated substance can be dried and solidified to be used as fuel or other effectively.

Since the treatment liquid after washing contains almost no harmful substances, it can be discharged to rivers or oceans as it is.

[0082]

As described above, the present invention decomposes a chlorine component contained in an object to be treated at a temperature not lower than the decomposition temperature of the chlorine component, and decomposes a harmful chlorine gas and a dechlorinating agent. Is reacted to form harmless chlorides, and harmless gas is obtained, and this gas is used as an auxiliary fuel for the blast furnace.

(1) Since a harmless gas containing no harmful chlorine-based gas is used, an effective resource recycling activity can be actually realized. Compatible and will not release dioxin from the blast furnace.

(2) Pretreatment of waste (separation, fine pulverization) is not required, which can contribute to a reduction in production cost.

(3) General municipal garbage can also be heat-treated and its exhaust gas can be used, so that waste treatment and resource re-use (recycling) can be realized, and this also helps to activate the steel industry. It has the effect of two birds with one stone.

(4) Further, no harmful chlorine component is present in the residue, and harmless chloride (NaCl) is generated and present, but this harmless chloride is easily dissolved in water or the like as a solution. Can be removed by washing.

Further, since the treatment liquid after washing does not contain a harmful chlorine component, it can be discharged to rivers and oceans as it is.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of the configuration of the present invention.

FIG. 2 is a conceptual diagram of a configuration of a conventional blast furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Receiving hopper part 2 ... Pulverization part 3 ... Sieving part 4 ... Supply hopper 5 ... Flow rate adjustment part 6 ... Conveyance piping 7 ... Pulverized coal hopper 8 ... Flow rate adjustment part 9 ... Air generation source 10 ... Powder distributor 11 ... Conveying piping 12 ... Blast furnace blowing branch pipe 13 ... Nozzle 14 ... Blast furnace 15 ... Tuyere 20 ... Tank 21 ... Sealing lid 22 ... Heating source 23 ... Valve exhaust pipe 24 ... Valve 25 ... Pump 26 ... Gas control means 27, 28: Valve 29: Gas storage tank 30: Gas supply pipe

Claims (13)

[Claims] An object to be treated is heat-treated to decompose a chlorine component contained in the object to be treated, and a harmful chlorine-based gas generated by the decomposition and a dechlorinating agent comprising a carbonic acid-based alkali substance are separated into: Reacts in a low-oxygen atmosphere to replace harmful chlorine-based gas with harmless chloride to produce harmless gas, which is blown from the blast furnace tuyeres as auxiliary fuel. Operating method of blast furnace. 2. The method for operating a blast furnace according to claim 1, wherein the dechlorinating agent is selected from a simple substance of a carbonate-based alkali substance, two or more simple substances, and a mixture of two or more simple substances. 3. The blast furnace operating method according to claim 1, wherein the dechlorinating agent is a carbonate-based sodium substance. 4. The dechlorinating agent is selected from a simple substance selected from sodium hydrogen carbonate, sodium carbonate, sodium sesquicarbonate and natural soda, a mixture of two or more simple substances, and a mixture of two or more simple substances. The method for operating a blast furnace according to claim 1. 5. The operation of a blast furnace according to claim 1, wherein the dechlorinating agent to be added is 0.05 to 10% by weight of the starting weight of the material to be treated. Method. 6. The dechlorinating agent to be added is 10 to 70% by weight based on the starting weight when the object to be treated is plastics containing a large amount of chlorine. The method for operating a blast furnace according to any one of the preceding claims. 7. The dechlorinating agent to be added is added in an amount equal to or more than the same amount as the amount of chlorine-based gas generated.
5. The method for operating a blast furnace according to any one of items 4 to 4. 8. The blast furnace according to claim 1, wherein the chlorinating agent to be added is added so as to have a chlorine-based gas emission amount equal to or less than an allowable emission standard. Operating method. 9. The operation of a blast furnace according to claim 1, wherein the dechlorinating agent is added at a time lower than the thermal decomposition temperature of the chlorine component, during thermal decomposition, after thermal decomposition, or in combination. Method. 10. The method for operating a blast furnace according to claim 1, wherein a temperature range of the heat treatment in a low oxygen atmosphere is from 200 ° C. to 1000 ° C. 11. The method for operating a blast furnace according to claim 1, wherein the use of the dechlorinating agent is any of charging, mixing, and spraying, or a combination thereof. 12. The method according to claim 1, wherein the means for thermally decomposing the chlorine component is carbonization. 13. The method according to claim 1, wherein the object to be treated is a solid, sludge, or exhaust gas.