JP2000074336A - Method for treating waste and waste treating facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a power generation with a high efficiency by blowing waste plastic containing chlorine to a char melting furnace, using it as an auxiliary fuel of the furnace, and treating the plastic containing the chlorine while suppressing generation of harmful substance such as dioxin re-synthetic catalyst or the like. SOLUTION: Waste plastic blowing units 27a, 27b and 27c are respectively disposed in a pretreatment furnace 1, a char melting furnace 9 and a combustion furnace 10. Waste plastic 28 containing chlorine is granulated with a polyvinyl chloride waste plastic, blown into the furnace 9 at 50 kg/hr, and a chlorine content is gathered in the melting furnace, generated combustible gas is wet cleaned, HCl, Cl and the like are removed, the gas is introduced into the furnace 10, and completely burned, thereby preventing a high temperature corrosion of a waste heat recovery boiler 12. Since the vinyl chloride contains a large quantity of ash content, the ash content is melt slagged, and volume reduced. Thus, a power generation of a high efficiency can be performed at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste disposal method for treating waste plastic together with municipal waste, industrial waste, and other combustible and incombustible waste.

[0002]

2. Description of the Related Art Conventionally, wastes composed of combustibles and non-combustibles such as municipal garbage and industrial wastes are generally treated as follows.
800-90 by stoker type incinerator and fluidized bed incinerator
After incineration at a temperature of 0 ° C, a method of landfill disposal of incinerated ash has been used. In recent years, however, due to the pressure of landfills nationwide, it has been required to reduce the volume of incinerated ash, make it more resources, and make it harmless. I have. Therefore, plasma arc furnaces and burner combustion furnaces are placed after the existing incinerators, and incineration ash treatment methods that melt incineration ash generated in the incinerator and turn it into slag have been developed. However, all of them require a large amount of external energy such as electric power and petroleum, and thus have a disadvantage that the cost burden is large.

As a waste disposal method for solving these problems, for example, “Environmental Facility” No. 65, page 8, line 6, waste in a pyrolysis furnace
After pyrolysis at a low temperature of about 600 ° C, organic matter in the waste is converted into pyrolysis char and pyrolysis gas, and incombustibles such as empty cans are separated by a separator, and then pyrolysis char and pyrolysis gas are melted in a melting furnace. Complete combustion at a high temperature of about 1300 to 1400 ° C using air to melt the ash contained in the pyrolysis char, and the molten ash is separated from the exhaust gas, then cooled and solidified to form granulated slag gasification. Melting methods have been proposed.

In this gasification and melting method, the ash is melted using the carbon contained in the pyrolysis char or pyrolysis gas as a fuel, so that the input of external energy can be greatly reduced. Furthermore, in order to effectively use waste as an energy resource,
Although waste power generation is being introduced, a steam turbine power generation system is generally employed in which high-temperature combustion exhaust gas is recovered by steam in a boiler, and the recovered steam is supplied to a steam turbine to generate electric power.

However, when treating waste containing chlorine, such as municipal waste, the chlorine is converted into hydrochloric acid gas or chlorine gas during combustion, and corrosive dusts such as alkali metal salts are included in the combustion exhaust gas. Therefore, if the temperature of the recovered steam is increased, the temperature of the heat transfer tubes in the superheated part of the boiler will increase, causing a problem of high-temperature corrosion due to hydrochloric acid gas and corrosive dust.To solve this problem, the recovered steam temperature must be increased. 300
℃ or less, sufficient power generation efficiency is 10 ~
15% cannot be obtained. (Power generation efficiency = about 10 to 15%) It has been attempted to raise the recovery steam temperature to about 400 ° C by using expensive corrosion-resistant steel pipes as the material of the waste heat recovery boiler. Must be done.

[0006] In order to further raise the temperature of the recovered steam, for example, “thermal nuclear power generation”, Vol. 48, N
o. As described on page 10, page 126, line 24, research on the selection of materials for the superheated section heat transfer tube aiming at a recovered steam temperature of 500 ° C. and a power generation efficiency of 30% is currently being conducted, but more expensive corrosion resistance is required. It is expected that it will be inevitable to become a steel pipe.

[0007] Therefore, as a gasification and melting method aimed at alleviating boiler corrosion by hydrochloric acid gas, a chlorine component is fixed in a pyrolysis char, and the pyrolysis gas and the pyrolysis char are separated and burned separately to form a chlorine component. A method has been proposed in which a boiler superheater is disposed in the passage of the combustion exhaust gas having a smaller amount of heat, and the steam is superheated with the combustion exhaust gas having less corrosion. For example, "Second Fluid Bed Symposium", p. 184, 21
As described in the line and "Monthly Global Environment", May 1997, page 43, line 10, a dechlorinating agent such as slaked lime is added to the pyrolysis furnace and pyrolyzed at 550-600 ° C. To transfer the chlorine to the pyrolysis char as CaCl ₂ , separate the pyrolysis gas discharged from the pyrolysis furnace from the pyrolysis char by a cyclone or the like, and obtain superheated steam from the combustion exhaust gas of the pyrolysis gas containing less chlorine. It is a furnace-combustion furnace separation type gasification and melting system.

On the other hand, in recent years, there has been a demand for effective use of waste plastic discharged as industrial waste or general waste. One of the effective use methods is to collect waste plastic energy as electric power by garbage power generation. Thermal recycling. However, in the case of treating waste plastic by an existing incinerator or gasification and melting method and performing garbage power generation, treatment of waste plastic containing chlorine is a major problem.

That is, when waste plastics containing a large amount of chlorine, such as polyvinyl chloride (PVC) and polyvinylidene chloride, are thermally decomposed or burned, a large amount of HCl gas or Cl ₂ gas is generated, and the HCl concentration in the combustion exhaust gas is increased. And Cl ₂
The concentration increases. For this reason, even when an expensive corrosion-resistant material is used for the boiler when recovering heat with the waste heat boiler, it is difficult to obtain high-temperature steam of 300 ° C. or higher, and only low power generation efficiency can be obtained. Further, when the chlorine concentration in the gas increases, there is a concern that the dioxin resynthesis catalyst (such as CuCl ₂ ) and the amount of dioxin generated may increase. Even if the gasification and melting method of the melting furnace-combustion furnace separation type is applied, a large amount of slaked lime must be put in to inject waste plastic into the pyrolysis furnace for desalination, resulting in an increase in fly ash generation. There is.

Therefore, even if the waste plastic containing chlorine is treated, high-efficiency power generation can be performed without causing corrosion of the waste heat recovery boiler by HCl and Cl _2, and the amount of the dioxin resynthesis catalyst and dioxin generated is increased. There is a demand for a waste plastic treatment method which does not cause an increase in slaked lime consumption or fly ash generation.

[0011]

SUMMARY OF THE INVENTION The present invention relates to the problem of high temperature corrosion of a waste heat recovery boiler due to chlorine content and the generation of harmful substances such as dioxin resynthesis catalyst (CuCl ₂ ) when treating waste plastic containing chlorine. It is an object of the present invention to provide a waste disposal method and a waste disposal facility which can solve the above-mentioned problem and can generate power efficiently at low cost and can reduce the volume of incinerated ash.

[0012]

Means for Solving the Problems The first invention of the present invention is:
Waste consisting of combustibles and incombustibles is pre-treated in a pre-treatment furnace to generate pyrolysis char and pyrolysis gas, and chlorine contained in the waste is fixed in the char to form a solid-gas The pyrolysis char and pyrolysis gas are separated by a separator, and the pyrolysis gas is introduced into a combustion furnace, completely burned by air and introduced into a waste heat recovery boiler, while the pyrolysis char is introduced into a char melting furnace. Flammable gas with oxygen or oxygen-enriched air, or complete combustion with air,
This is a waste treatment method in which ash is melted and turned into slag, and the gas generated from the char melting furnace is wet-washed.Waste plastic containing chlorine is blown into the char melting furnace and used as an auxiliary fuel for the char melting furnace. , HCl, C
Disposal characterized by preventing high-temperature corrosion of a waste heat boiler due to generation of l _{2 and the} like, and also treating waste plastic containing chlorine while suppressing generation of harmful substances such as dioxin resynthesis catalyst (CuCl ₂ ). It is a material processing method. A second invention is the waste disposal according to the first invention, wherein chlorine-free waste plastic is blown into one or more furnaces of a pretreatment furnace, a char melting furnace, and a combustion furnace to be used as an auxiliary fuel. It is a material processing method. A third invention is a waste treatment method according to the first invention, wherein a combustible gas generated in a char melting furnace after wet cleaning is introduced into a combustion furnace.

[0013] A fourth invention is a pretreatment furnace for generating pyrolysis char and pyrolysis gas from waste consisting of combustibles and incombustibles, and for immobilizing chlorine in the waste in the char;
A solid-gas separation device for solid-gas separation of the pyrolysis char and the pyrolysis gas, a char melting furnace for supplying oxygen or oxygen-enriched air or air to the pyrolysis char to melt ash in the char,
A combustion furnace that completely burns the pyrolysis gas, a waste heat recovery boiler and a power generator that uses the combustion gas from the combustion furnace, and HCl in the gas by wet-cleaning the combustible gas or the complete combustion gas generated from the char melting furnace. Cleaning device for removing methane, Cl ₂ etc., gas cooling device for cooling exhaust gas from combustion furnace and char melting furnace, dust collecting device for separating fly ash in exhaust gas, and waste plastic installed in each furnace A waste treatment facility comprising a supply device.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, pyrolysis char and pyrolysis gas are generated from chlorine-containing waste such as municipal waste such as combustibles and incombustibles, and chlorine in the waste is fixed in the char. Separation of pyrolysis char from pyrolysis gas, complete combustion of pyrolysis gas, utilization for power generation through waste heat recovery boiler, melting of ash in pyrolysis char to slag In the flue gas and become the main cause of high-temperature corrosion of the waste heat recovery boiler,
After collecting in the char melting furnace the CuCl ₂ which becomes a dioxin resynthesis catalyst and the chlorine which causes dioxin generation in the flue gas, the chlorine generated by the char melting furnace is washed to remove the chlorine. This method is applied in the waste treatment method described above, in which waste plastic pre-sorted is selectively blown into a char melting furnace, pretreatment furnace, combustion furnace, etc. It is characterized by processing itself.

The waste plastics include those containing chlorine such as polyvinyl chloride and polyvinylidene chloride and those containing no chlorine. In the present invention, waste plastics containing chlorine such as polyvinyl chloride and polyvinylidene chloride are used. Is blown into a char melting furnace, and chlorine-free waste plastic is blown by selecting one or more of a pretreatment furnace, a char melting furnace, and a combustion furnace.

The waste plastic containing chlorine is blown into the char melting furnace because chlorine is collected in the melting furnace, the combustible gas generated is wet-cleaned to remove HCl, Cl _{2 and the} like, and introduced into the combustion furnace. It is for burning to prevent high-temperature corrosion of the waste heat recovery boiler. Further, since ash is contained in PVC, the ash can be converted into molten slag.

When chlorine-containing waste plastic is blown into a combustion furnace, HC contained in the exhaust gas may be mixed.
Since it is introduced into the waste heat recovery boiler without removing l, Cl ₂ etc., it becomes impossible to prevent high temperature corrosion,
In addition, there is a concern that the amount of CuCl ₂ or dioxin itself which becomes a dioxin resynthesis catalyst by being mixed in the exhaust gas increases, and it is necessary to provide an expensive separate process for eliminating these concerns, which increases the cost burden. Further, when chlorine-containing waste plastic is blown into the pretreatment furnace, an increase in the use of desalinating materials such as slaked lime and an increase in the amount of fly ash occur. On the other hand, in the case of waste plastic containing no chlorine,
Since there is no such problem due to chlorine content as in the case of waste plastic containing chlorine, it can be blown into each furnace of a pretreatment furnace, a char melting furnace, and a combustion furnace.

When chlorine-containing waste plastic is blown into the char melting furnace, chlorine-free waste plastic may be blown together. The blowing of chlorine-containing waste plastic and chlorine-free waste plastic into each furnace may be carried out by itself, but it functions as a fuel. And the amount and ratio of non-flammable materials. The amount of oxygen or oxygen-enriched air or air to be blown into each furnace is determined according to the amount and ratio of combustible and non-flammable materials in waste, the amount of waste plastic blown, and the like.

The waste incineration equipment to which the present invention is applied is configured, for example, as shown in FIG. In FIG.
Reference numeral 1 denotes a shaft furnace type direct melting furnace as a pretreatment furnace, which converts wastes 2 consisting of combustible and incombustible substances into coke / limestone 3.
And oxygen or oxygen-enriched air 4 and air 5 are blown thereinto to perform a melting treatment at 1700 to 1800 ° C. to form a pyrolysis char 6, a pyrolysis gas 7, slag or metal M
S is generated, and chlorine in the waste 2 is thermally decomposed.
It is immobilized inside.

Reference numeral 8 denotes a solid-gas separation device such as a cyclone for separating the pyrolysis char 6 and the pyrolysis gas 7 from the pretreatment furnace 1 into solid and gas. Reference numeral 10 denotes a combustion furnace, which introduces the pyrolysis gas 7 from the solid-gas separation device 8 and blows air 11 to complete combustion. Reference numeral 9 denotes a char melting furnace which introduces the pyrolysis char 6 from the solid-gas separation device 8 and blows oxygen or oxygen-enriched air 16 to reduce the ash content of the pyrolysis char 6 to 1
It melts at 300 to 1400 ° C. to form slag 17 and generates combustible gas 18.

Reference numeral 12 denotes a waste heat recovery boiler which recovers heat from a combustion gas 13 from a combustion furnace 10 to generate a superheated steam 14 at a level of 400 to 500 ° C. Reference numeral 15 denotes a steam turbine power generator which rotates the steam turbine by using superheated steam 14 from the waste heat recovery boiler 12 to generate power. Numeral 20 denotes a wet cleaning device for wet cleaning the combustible gas 18 from the char melting furnace 9 to remove chlorine in the combustible gas.
8 is introduced into the combustion furnace 10 as fuel.

If, for example, only the complete combustion gas 21 is exhausted from the char melting furnace 9 instead of the combustible gas 18, the complete combustion gas 21 is discharged through the gas cooling device 22 or the wet cleaning device 20 to the dust collecting device. 23. Exhaust gas 24 from waste heat recovery boiler 12, combustion furnace 10
Is introduced into the gas cooling device 22.
Each of the gases introduced into the cooling device 22 is cooled to about 200 ° C. or less, and then cooled by a dust collecting device 23 such as a bag filter.
And fly ash 19 is collected, and each gas is discharged from the smoke exhaust device 26 as a clean gas.

According to the present invention, in the waste treatment facility configured as described above, waste plastic is used as fuel,
The waste plastic itself is also treated, and for that purpose, waste plastic blowing devices 27a, 27b, 27c are arranged in the pretreatment furnace 1, the char melting furnace 9, and the combustion furnace 10.

As described above, the waste plastic includes a waste plastic 28 containing chlorine and a waste plastic 29 containing no chlorine.
Numeral 8 denotes blowing into the char melting furnace 9, and waste plastic 29 containing no chlorine is blown into the pretreatment furnace 1, the char melting furnace 9, and the combustion furnace 10. This waste plastic 28,
For blowing of 29, nitrogen or air may be used as a carrier gas, or a gas prepared separately may be used. Moreover, when blowing into a pretreatment furnace, it may be directly charged without using a carrier gas. Reference numeral 25 in the figure denotes a nozzle used for blowing oxygen or oxygen-enriched air 4, 16 or air 5, 11, and waste plastics 28, 29.

The reason why the waste plastic 28 containing chlorine is blown only into the char melting furnace 9 is that, as described above, chlorine is collected in the melting furnace, and the combustible gas generated is wet-cleaned to form HC.
The purpose is to remove l, Cl _{2 and the} like, introduce them into the combustion furnace 10 and completely burn them, so that high-temperature corrosion of the waste heat recovery boiler 12 can be prevented. Further, since a large amount of ash is contained in PVC, the ash is melted into slag to reduce the volume.

On the other hand, waste plastics 29 containing no chlorine
In the case of the above, since the above-mentioned problem due to the chlorine content does not occur as in the case of the waste plastic 28 containing chlorine, it can be blown into each of the pretreatment furnace 1, the char melting furnace 9 and the combustion furnace 10, and the char melting furnace 9 may be blown together with the waste plastic 28 containing chlorine.

The present invention is not limited to the waste incineration process using the waste incineration equipment shown in FIG. For example, in the above example, the shaft furnace type direct melting furnace 1 was used as the pretreatment furnace, but it is not particularly limited as long as it has a gas desalination function, and it is a fluidized bed partial combustion type or an external heat kiln type. Low temperature pyrolysis furnace (400-600 ℃)
Etc. can also be used.

The waste treatment equipment and the waste treatment method according to the present invention include a waste condition to be treated, a waste treatment condition,
Depending on the conditions of the waste plastic, the scale of the treatment, and the like, the configuration of the composition may be changed within the scope of the claims.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Using a waste treatment facility as shown in FIG.
When treating municipal garbage, waste plastics 28 containing chlorine are blown into the char melting furnace 1 during processing, and plastic 29 without chlorine is blown into the shaft furnace type direct melting furnace (pretreatment furnace) 1 to generate waste. Processing was performed. Implementation conditions and implementation results are described below.

With a calorific value of about 2000 kcal / kg and a flammable content of 45
%, Moisture 45%, empty cans, empty bottles, rubble, etc., about 5 incombustibles
%, About 0.5% chlorine and municipal waste and separately collected waste plastic were treated at a throughput of 100 tons / day.
The waste plastic 28 containing chlorine is a polyvinyl chloride waste plastic, and is granulated into the char melting furnace 9 at 50 kg / H.
The chlorine-free waste plastic 29 mainly composed of polyethylene, polypropylene, polystyrene and the like was blown into the combustion furnace 10 at 200 kg / hr.

[0031] The shaft furnace type direct melting furnace 1, an oxygen gas 240 nm ³ / Hr, air is blown 2700 nm ³ / Hr, coke 0.1 tons / Hr of calorific value 7500kcal / kg, limestone 0.3 t / Hr And the waste was melted.
As a product from the shaft furnace type direct melting furnace 1, a melt MS (slag and metal) 490 kg / Hr, a pyrolysis gas 7 of 7000 Nm ³ / Hr, and a pyrolysis char 6 of 170 kg / Hr were obtained. The melt MS can be easily separated into slag and metal by magnetic separation. For example, slag can be reused as civil engineering and construction materials, and metal can be reused as counterweight of heavy equipment.

On the other hand, the pyrolysis char 6 and the pyrolysis gas 7
Separated by a cyclone 8 at the later stage, the pyrolysis char 6 was introduced into a char melting furnace 9, and the pyrolysis gas 7 was introduced into a combustion furnace 10. In the char melting furnace 9, the oxygen gas 16 is supplied at 73 Nm ³ / Hr
And gasify the char at 1400 ° C. to generate a calorific value of 1.
The combustible gas 18 of 800 kcal / Nm ³ was 180 Nm ³ / Hr generated.

In the combustion furnace 10, air 16000Nm ³ / Hr
The combustible gas 18 generated by the pyrolysis gas 7 and the char melting furnace 9 and wet-cleaned by the wet cleaning device 20 was completely burned at 900 to 1000 ° C. Since the flue gas from the combustion furnace 10 is free of corrosive components such as HCl and alkali dust, the steam obtained by heat recovery in the waste heat boiler 12 can be heated to 500 ° C. and 100 atm. there were. The steam turbine 15 was turned by this superheated steam to generate power, and 3800 kW of power was obtained. The power generation efficiency at this time was about 30%, which was a value that could be sufficiently evaluated. The exhaust gas after the heat recovery by the waste heat boiler 12 was cooled by a gas cooling device 22, purified by removing fly ash 19 by a dust collector 23 (bag filter), and discharged from a smoke exhaust device 26. Slag 17 discharged from the char melting furnace 9
Was 85 kg / Hr.

[0034]

According to the present invention, waste plastic containing chlorine or waste plastic containing no chlorine is selected as a fuel for a pretreatment furnace, a combustion furnace, a char melting furnace, etc. used in treating waste such as municipal waste. It is a process that injects the waste gas itself and treats itself. It solves the problem of high-temperature corrosion of the waste heat recovery boiler due to chlorine content and the problem of the generation of harmful substances such as dioxin resynthesis catalyst (CuCl ₂ ) while reducing cost and cost. Efficient power generation is possible, the volume of incinerated ash (ash) can be reduced, and the processing cost burden can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory side view showing an example of the arrangement of waste treatment facilities according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 pretreatment furnace 2 waste 3 coke, limestone 4 oxygen or oxygen-enriched air 5 air 6 pyrolysis char 7 pyrolysis gas MS slag, metal 8 solid-gas separation device (cyclone) 9 char melting furnace 10 combustion furnace 11 air 12 Waste heat recovery boiler 13 Combustion gas 14 Superheated steam 15 Steam turbine generator 16 Oxygen or oxygen-enriched air 17 Slag 18 Combustible gas 19 Fly ash 20 Wet cleaning device 21 Complete combustion gas 22 Gas cooling device 23 Dust collector (bag filter) 24 Exhaust gas 25 Nozzle 26 Smoke exhaust device 27a-27c Waste plastic blowing device 28 Waste plastic containing chlorine 29 Waste plastic not containing chlorine

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F23G 5/16 ZAB F23G 5/16 ZABE 7/12 ZAB 7/12 ZABZ F23J 15/02 F23J 15/00 C (72) Inventor Hachiro Harajiri 46-59, Nakahara, Tobata-ku, Kitakyushu-shi, Fukuoka New Nippon Steel Corporation Engineering Business Headquarters Engineering Business Headquarters Co., Ltd. (72) Inventor Sou Ono 46-59 Ohara Nakahara, Tobata-ku, Kitakyushu-shi, Fukuoka New Nippon Steel Corporation Engineering Business Headquarters F-term (reference) DA03 DA18 FA10 FA21 3K070 DA01 DA05 DA06 DA08 DA32 DA35 DA49 DA56 DA87 3K078 AA05 AA10 BA03 B A21 BA22 BA26 CA02 CA06 CA21 CA24

Claims (4)

[Claims] 1. A waste comprising combustibles and non-combustibles,
Pre-treatment in a pre-treatment furnace generates cracked char and pyrolysis gas, and also fixes the chlorine contained in the waste in the char, and separates the pyrolysis char and pyrolysis gas with a solid-gas separator. Separated, pyrolysis gas is introduced into a combustion furnace and completely burned by air and introduced into a waste heat recovery boiler, while pyrolysis char is introduced into a char melting furnace and converted into combustible gas with oxygen or oxygen-enriched air Or a method of treating waste by completely burning with air and melting ash to form slag and wet-cleaning the gas generated from the char melting furnace by blowing chlorine-containing waste plastic into the char melting furnace. , As a supplementary fuel for char melting furnace, and to prevent high temperature corrosion of waste heat boiler due to generation of HCl, Cl _2, etc.
₂ ) etc., while treating waste plastics containing chlorine while suppressing the generation of harmful substances such as ₂ ). 2. The waste disposal method according to claim 1, wherein the chlorine-free waste plastic is blown into one or more of a pretreatment furnace, a char melting furnace, and a combustion furnace to be used as an auxiliary fuel. . 3. The waste disposal method according to claim 1, wherein the combustible gas generated in the char melting furnace after the wet cleaning is introduced into the combustion furnace. 4. A pretreatment furnace for generating pyrolysis char and pyrolysis gas from waste consisting of combustibles and incombustibles, and fixing chlorine in the waste in the char, a pyrolysis char and pyrolysis gas A gas-solid separation device that separates the pyrolysis char, a char melting furnace that supplies oxygen or oxygen-enriched air or air to the pyrolysis char to melt ash in the char, and a combustion furnace that completely burns the pyrolysis gas, A waste heat recovery boiler and a power generator using combustion gas from a combustion furnace, and a wet cleaning device for performing wet cleaning of combustible gas or complete combustion gas generated from a char melting furnace to remove HCl, Cl _{2 and the} like in the gas. Waste characterized by having a gas cooling device for cooling exhaust gas from a combustion furnace and a char melting furnace, a dust collecting device for separating fly ash in exhaust gas, and a waste plastic supply device disposed in each furnace. Processing equipment .