WO2001090645A1

WO2001090645A1 - Wastes treating method and device

Info

Publication number: WO2001090645A1
Application number: PCT/JP2000/003306
Authority: WO
Inventors: Takashi Noto; Akira Nakamura; Seiji Kinoshita; Hajime Akiyama; Takuya Shinagawa
Original assignee: Nkk Corporation
Priority date: 2000-05-24
Filing date: 2000-05-24
Publication date: 2001-11-29
Also published as: KR100447009B1; EP1284389A4; KR20020025900A; EP1284389A1

Abstract

A wastes treating method comprising the steps of incompletely burning or partially oxidizing wastes in a partial oxidation furnace for causing a combustion reaction to generate a combustible gas having an oxygen-equivalent concentration of -30 to 1% at the outlet of the partial oxidation furnace, introducing the combustible gas into a dust separator at 250 to 800°C to reduce a dust concentration to up to 0.1g/Nm3, removing, as required, hydrogen chloride from the dedusted combustible gas by a wet type gas treating device down to up to 20 ppm, and then burning the gas at high temperatures in a combustion furnace, whereby wastes are partially oxidized to keep low a dust concentration otherwise causing the corrosion of boiler tubes, and an efficient heat recovery from a combustion exhaust gas is ensured.

Description

TECHNICAL FIELD The present invention relates to a method and an apparatus for treating waste. BACKGROUND ART Japanese Unexamined Patent Publication No. Hei 7-35322 and Japanese Unexamined Patent Publication No. 9-159132 disclose a method for treating waste which is obtained by partially oxidizing municipal solid waste or industrial waste (hereinafter, simply referred to as waste), converting the waste into gas, and burning the waste. Has been proposed.

FIG. 10 schematically shows an example of a typical method disclosed in Japanese Patent Application Laid-Open No. 7-35322. The waste is gasified in a partial combustion fluidized bed furnace 1 in a fluidized bed temperature of 450 to 650 ° (:, reducing atmosphere with an air ratio of about 0.15 to 0.5). The gas is introduced into the secondary combustion furnace 3 via the dust collector 2. The produced gas is mixed with the secondary air in the secondary combustion furnace 3 and is completely burned at a high temperature of 800 to 1000 ° C. A salt recovery agent is supplied to suppress the generation of hydrogen chloride gas for heat recovery, and a dust recovery line 6 is installed below the dust collector 2, and some of the desalinating agent and the dust are collected. After a part or the whole amount is cooled by the cooler 7, it is returned to the partial oxidation fluidized bed furnace 1 again.

FIG. 11 schematically shows an example of a typical method disclosed in Japanese Patent Application Laid-Open No. 9-159132. ·

Combustion exhaust gas generated by burning refuse in the combustion furnace is cooled to 450 to 650 ° C by heated water 20 is introduced from the economizers 8 in the waste heat boiler 4, is dust removal by the filter ⁷ 9 . Part or all of the flue gas discharged from the filter 9 is supplied to the heating furnace 10 and is heated to a high temperature by reheating using the auxiliary fuel 21, and the waste heat is generated by the steam superheater 11. It is used to heat saturated steam 22 coming from boiler 4 to around 500 ° C. A part of the flue gas is recovered from the waste heat by the economizer 8 and the air preheater 12 and then discharged from the chimney 14 via the induction blower 13. However, such a waste disposal method has a high dust concentration and is disadvantageous in terms of dust removal, and also causes corrosion of the poiler tube due to salt in the dust and the like in a poiler installed downstream for heat recovery. However, there is a problem that the combustion furnace makes it impossible to recover waste heat effectively by reducing the amount of unburned gas in the combustion exhaust gas. DISCLOSURE OF THE INVENTION An object of the present invention is to provide a waste treatment method and apparatus which can partially oxidize waste so that the dust concentration does not become high and can efficiently recover heat from combustion exhaust gas. The above-mentioned object is a step of incompletely burning or partially oxidizing waste in a partial oxidation furnace with a combustion reaction to generate a combustible gas having an oxygen equivalent concentration of −30 to 1% at the outlet of the partial oxidation furnace. It has a process of introducing this combustible gas to a dust remover at 250 to 800 ° C to reduce the dust concentration to 0.1 lg / Nm ³ or less, and a process of burning the combustible gas after dust removal at a high temperature in a combustion furnace. Achieved by waste disposal methods. A step of incompletely burning or partially oxidizing the waste in a partial oxidation furnace accompanied by a combustion reaction to produce a combustible gas having an oxygen equivalent concentration of −30 to ^ at the outlet of the partial oxidation furnace; A process of introducing gas into a dust remover at 250 to 800 ° C to reduce the dust concentration to 0.1 lg / Nm ³ or less; and introducing a combustible gas after dust removal to a wet gas treatment device to reduce a salt concentration of hydrogen. It is also possible to use a waste treatment method that includes a step of reducing the amount of combustible gas after wet gas treatment to 20 ppm or less and a step of burning the combustible gas after the wet gas treatment in a combustion furnace at a high temperature. These waste treatment methods include partial oxidation furnaces that incompletely burn or partially oxidize waste that produces combustible gas with an oxygen equivalent concentration of -30 to ^ at the furnace outlet, and 250 to 800 ° C. Waste treatment equipment equipped with a dust remover that reduces the dust concentration of this combustible gas to 0.1 lg / Nm ³ or less, and a combustion furnace that burns combustible gas after dust removal at a high temperature, or the oxygen equivalent concentration at the furnace outlet a partial oxidation furnace but to incomplete combustion or partial oxidation of waste to produce a combustible gas, which is an 30 to 1%, the Das Bok concentration of the combustible gas 0. lg / Nm ³ in the following 250 to 800 ° C Waste treatment equipment equipped with a dust removal device that reduces the concentration of hydrogen chloride in combustible gas after dust removal to 20 ppm or less, and a combustion furnace that burns combustible gas after wet gas treatment at high temperatures Is done. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram schematically showing one embodiment of a waste disposal apparatus according to the present invention. Fig. 2 shows the relationship between the dust concentration after dust removal and the service life of the boiler tubes installed downstream.

FIG. 3 is a view showing a shape of the ceramic filter 1.

FIG. 4 is a diagram schematically showing another embodiment of the waste treatment apparatus according to the present invention.

FIG. 5 is a diagram schematically showing another embodiment of the waste treatment apparatus according to the present invention.

FIG. 6 is a diagram schematically showing another embodiment of the waste disposal apparatus according to the present invention. — '. ·

7A and 7B are diagrams schematically showing another embodiment of the waste treatment apparatus according to the present invention.

FIG. 8 is a diagram schematically showing another embodiment of the waste treatment apparatus according to the present invention. 9A and 9B are diagrams schematically showing another embodiment of the waste treatment apparatus according to the present invention.

FIG. 10 is a diagram schematically showing an example of a conventional waste treatment method.

FIG. 11 is a diagram schematically showing another example of a conventional waste treatment method. BEST MODE FOR CARRYING OUT THE INVENTION FIG. 1 schematically shows an embodiment of a waste treatment apparatus according to the present invention.

This system consists of a partial oxidation furnace 1 that incompletely burns or partially oxidizes waste, a dust removal device 2 that reduces the concentration of combustible gas dust, a combustion furnace 3 that burns combustible gas after dust removal at a high temperature, It consists of a collection of poilers 4 for recovery.

The waste put into the partial oxidation furnace 1 is partially oxidized by burning a gas mainly composed of air having a controlled oxygen concentration by the steam and the exhaust gas, thereby producing a combustible gas. At this time, if the concentration of the combustible gas generated in terms of oxygen at the outlet of the furnace 1 is less than -30%, a problem such as adhesion of a strong reducing gas may occur, and if it exceeds 1, dioxin etc. can be sufficiently reduced. Since combustion cannot be performed, it is necessary to adjust the air ratio to 0.15 to 0.9, for example, so that it becomes -30 to ^. By controlling the oxygen equivalent concentration within this range, the risk of explosion due to combustible components and oxygen is reduced, and the fluctuation in the potential of the combustible gas generated is reduced, enabling stable operation. Here, the oxygen equivalent concentration is a value defined by a difference between an oxygen concentration in an atmosphere and an oxygen concentration considered to be consumed by a gas that may be oxidized. For example, oxygen (0 ₂₎ is 2%, carbon monoxide (CO) 4% hydrogen (¾) is ¾, if the methane (CH ₄₎ is present 1%, 4% CO oxidizes C0 _In order to become ₂ , it consumes 0 ₂ of ^, and similarly, ₂ of H ₂ consumes 1% of 0 _2, and 1% of methane CH ₄ consumes 0 ₂ of ₂ , so the oxygen equivalent concentration is 2 -(2 + 1 +2) = -3%. This value is an index indicating the degree of combustion of the partial oxidizing gas in the atmosphere and the degree of the air ratio in the combustion up to that time. The smaller the value, the higher the potential as a combustible gas. The temperature in the furnace 1 is set to 400 to 800 ° C, which is such that the waste can self-combust and partially oxidize.

Combustible gas produced, the temperature by residence time in the partial oxidation furnace 1 is controlled to 250 to 800 ° C, until the dust concentration is sent to the dust collector 2 is below 0. 1 g / Nm ³ Dust is removed.

The temperature of the flammable gas sent to the dust removal device 2 is 250 to 800 ° (and more preferable) because tar and the like adhere to the device at 250 ° C or less and molten salt in dust adheres to the device at 800 ° C or more. Needs to be controlled at 250-650 ° C.

When the combustible gas is sent to the dust removing device 2 at such a relatively low temperature, dust can be removed without excessive cooling via equipment such as a cooling tower.

Figure 2 shows the relationship between the dust concentration after dust removal and the service life of the boiler tubes installed downstream. It can be seen that the service life of the poiler tube is significantly improved if the dust concentration after the P residual dust is set to 0.1 lg / Nm ³ or less. This is because the amount of salt in the dust is reduced, and the corrosion of boiler tubes and the like is suppressed.

Depending on the temperature of the combustible gas, a bag filter, a ceramic filter, a high-temperature electric precipitator, an inertial precipitator, a high-performance cyclone, a centrifugal precipitator, or the like is used as the dust removing device 2. Also, it is desirable to use a filter-type dust collector equipped with a candle-shaped ceramic filter and filter cloth, as shown in Fig. 3, and an 82-cam-shaped ceramic filter with a mesh size of 10 mm or less.

If the dust adhering to the filter body is periodically removed, the dust is efficiently removed and the emission of harmful gas is further suppressed. For this removal, it is desirable to use a gas with an oxygen concentration of 5% or less or nitrogen gas in order to suppress the oxidation of combustible gas and avoid the danger of unnecessary explosion or combustion. The gas having an oxygen concentration of 5 or less can be obtained by recirculation of exhaust gas, pressure swing adsorption, or membrane separation. Considering the peeling effect of the deposited dust, the conditions of brushing method, a gas pressure LKG / cm ² or more, a few seconds to several hours brushing intervals, to the the brushing time 0.02 seconds to several tens seconds Is desirable. It is desirable that the temperature of the gas to be removed be equal to or higher than the temperature of the combustible gas in order to prevent the temperature of the combustible gas from lowering.

Furthermore, the coating layer on the surface of the dust collector may peel off due to the blowing of gas to blow off the gas, but if gas is blown when the differential pressure across the dust collector reaches a certain set value, It can be completely prevented.

The combustible gas that has been dust-removed by the dust-removing device 2 is burned in the combustion furnace 3 to reach a high temperature of about 1000 ° C. Here, since the combustion is performed by mixing the oxidizing agent, the complete combustion is performed, so that the emission of unburned gas such as CO is almost completely suppressed. In addition, since combustible gas has been subjected to dust removal in advance, the concentration of aromatic organic compounds due to soot is reduced, and as a result, the concentration of dioxins and furan, which are incomplete combustion products, is also reduced. You. If a combustible gas is continuously burned by arranging an ignition reducer in the combustion furnace 3, it is possible to avoid the danger of misfiring and mixing of combustible gas and air again to explode.

If the boiler 4 is arranged downstream of the combustion furnace 3, heat can be efficiently recovered from the combustion gas, so that a high-temperature and high-pressure boiler of, for example, 300 or more and 20ata or more can be realized. In addition, recovery of high-temperature air is possible if necessary. In the example of FIG. 1, the poiler 4 is provided downstream of the combustion furnace 3, but the poiler 4 may be provided in the combustion furnace 3. Since dust has been removed in advance, corrosion of the boiler tube due to dust can be suppressed. When recovering heat from a high-temperature field with an exhaust gas temperature of 600 ° C or higher, where the corrosion effect of hydrogen chloride gas increases, use a boiler tube made of a corrosion-resistant ceramic to extend the life of the boiler tube . The exhaust gas after heat recovery passes through a downstream exhaust gas treatment facility (not shown) and is discharged from the chimney. As shown in Fig. 4, a dust-burning furnace 15 for burning the dust removed by the dust remover 2 is installed in the waste treatment device of Fig. 1, and the removed dust is replaced with a gas containing oxygen by 400%. By burning at ~ 750 ° C, unburned components can be reduced to a certain concentration (for example, 6wt) or less while fixing the salts contained in the dust. In addition, since the gas generated during combustion contains unburned components, if it is introduced into the partial oxidation furnace 1 through conduits, etc. Effective use can be achieved. FIG. 5 schematically shows another embodiment of the waste treatment apparatus according to the present invention. In this device, a wet gas treatment device 5 is provided between a dust removal device 2 and a combustion furnace 3 of the device in FIG.

The combustible gas after dust removal is introduced into this wet gas treatment device 5, and the concentration of the neutralizing agent such as caustic soda is changed to reduce the hydrogen chloride concentration to 20 ppm or less. This will reduce the occurrence of corrosion and drastically reduce the corrosion of boiler tubes and other equipment downstream. Therefore, parts and the like that have conventionally been made of materials such as ceramics having high corrosion resistance can be replaced with inexpensive materials.

The conditions other than introducing the combustible gas after dust removal into the wet gas treatment device 5 and reducing the hydrogen chloride to 20 ppm or less were all the same as those in Fig. 1 where the wet gas treatment device 5 was not installed. The same is true. Example 1

FIG. 6 schematically shows another embodiment of the waste treatment apparatus according to the present invention. The configuration of this device is the same as that of Fig. 1 except that a fluidized bed furnace 1 is used as a partial oxidation furnace.

Supply municipal solid waste at lt / h to fluidized bed furnace 1 with a fluidized air temperature of 20 to 650 ° (:, sand layer temperature of 400 to 700 ° C, and an air ratio of 0.2 to 8 A partial oxidization was performed to produce a combustible gas.

The combustible gas was supplied to the dust remover 2 at 250 to 800 ° C, and the dust was removed by a candle-shaped ceramic filter. Ceramic fill evening one _{_{candle-shaped, S i 0 2, A1 2}} 0 3, S i C, Kojiyuraito, made from the composite of these materials or inorganic materials similar to it, is a ceramic fiber-type or a porous type . To dislodge the dust removing apparatus 2, using a re-circulating oxygen concentration of 5% or less and the gas and the nitrogen gas exhaust, 3~7kg / cm ² pressure flicked, brushing 5 seconds apart - 50 minutes, payment The drop time was 0.1 to 20 seconds. As a result, the dust concentration was 5 to 20 g / Nm ³ before flowing into the dust removing device 2, but was reduced to 0.1 lg / Nm ³ or less. After removal of the removed dust, it was detoxified in a melting furnace and an incinerator.

After the dust removal, the combustible gas was burned in the combustion furnace 3 to a temperature of 900 to 1000 ° C. At this time, it was possible to perform heat recovery using steam of 350 to 540 ° (: 50 to 100 ata) in the downstream poiler 4. Stainless steel, Inconel, and other alloy steels were used as the poiler tube. No remarkable corrosion was observed, and it was confirmed that the corrosion resistance could be used for several years depending on the material, and when high-temperature air was recovered, high-temperature air at 350 to 700 ° C could be recovered. Example 2

7A and 7B schematically show another embodiment of the waste treatment apparatus according to the present invention.

The configuration of the apparatus in FIG. 7A is the same as the apparatus in FIG. 1 except that a grate furnace 1 is used as a partial oxidation furnace. Further, in the apparatus shown in FIG. 7B, a boiler 3A is also provided in the combustion furnace 3 of the apparatus shown in FIG. 7A.

Supply municipal solid waste to the grate furnace 1 with an oxidizing air temperature of 20 to 250 ° C and an upper temperature of 500 to 800 ° C, and operate with an air ratio of 0.3 to 0.9. And partial oxidation to produce combustible gas.

The combustible gas was supplied to the dust remover 2 at 250 to 800 ° C, and the dust was removed by the candle-shaped ceramic filter and the honeycomb-shaped ceramic filter. Ceramic Phil evening one consists _{_{_{S i0 2, A1 2 0 3}}} , S i co one Jiyuraito composite of these materials or inorganic materials similar to it, is a ceramic fiber-type or multi-porous type. Filtration apparatus 2 of the flicked uses nitrogen gas, 3~7kg / cm ² pressure flicked, brushing 10 seconds to 20 minutes apart, was the brushing time from 0.05 to 15 seconds. As a result, the dust concentration was reduced from i to 5 g / Nm ³ before flowing into the dust removing device 2 to 0.1 Ig / Nm ³ or less. After removal of the removed dust, the melting furnace and the firing It was detoxified in an incinerator.

The combustible gas after dust removal was brought to a temperature of 900 to 1100 which was burned in the combustion furnace 3. In Combustion Furnace 3, in order to avoid danger such as explosion, the combustible gas was continuously burned using a pilot wrench (not shown) with the ignition source always on. The output of this parner is tens of thousands to hundreds of thousands of kcal / h, and natural gas or kerosene was used as fuel.

At this time, heat recovery is performed using steam of 540 ° (:, lOOata) in both the poiler 4 installed downstream of Fig. 7A, the poiler 3A installed in the combustion furnace 3 in Fig. 7B, and the downstream poiler 4 Although stainless steel, Inconel, and other alloy steels were used as the poiler tube, no significant corrosion was observed, and stable operation was possible for one year or more.

FIG. 8 schematically shows another embodiment of the waste disposal apparatus according to the present invention. The configuration of this device is the same as the device in Fig. 5 except that a fluidized bed furnace 1 is used as a partial oxidation furnace.

Fluidized air temperature is 20 to 650 ° C, sand layer temperature is 400 to 70 (Waste municipal solid waste is supplied to the fluidized bed furnace 1 of TC at lt / h, and the air ratio is 0.2 to 0.8. The partial oxidation was carried out to produce a combustible gas.

Combustible gas is supplied to the filtration apparatus 2 with two hundred and fifty to eighty (TC, are dust by ceramic filter one candle shape. Ceramic fill evening one candle shape, Si0 _2, A1 ₂ 0 _3, Si Kojiyuraito, these It consists of a composite of the same material or an inorganic material similar to it, and is of the ceramic fiber type or porous type.To remove the dust removal device 2, use a gas with an oxygen concentration of 5% or less by recirculating the exhaust gas. Using nitrogen gas, the sweeping pressure was 3 to 7 kg / cm ² , the sweeping interval was 5 seconds to 50 minutes, and the sweeping time was 0.1 to 20 seconds. Although it was 5 to 20 g / Nm ³ before the inflow of ash, it was reduced to less than 0.1 lg / Nm ^{3. After} removal of the removed dust, it was detoxified in a melting furnace and an incinerator. The combustible gas after dust removal was introduced into the wet gas treatment equipment 5, and the hydrogen chloride in the gas was reduced from 400 ppm before treatment to 20 ppm or less.

The combustible gas with reduced hydrogen chloride was brought to a temperature of 900 to 1000 ° C, which was burned in the combustion furnace 3. At this time, heat recovery could be performed using steam at 350 to 540 ° C and 50 to 100 ata in the downstream poirer 4. Although stainless steel was used for the boiler tube, no significant corrosion was observed, and it was confirmed that some materials could be used for several years. In addition, when high-temperature air was collected, high-temperature air could be collected in the range of 350 to 700. Example 4

9A and 9B schematically show another embodiment of the waste treatment apparatus according to the present invention.

The configuration of the apparatus in FIG. 9A is the same as the apparatus in FIG. 5 except that a grate furnace 1 is used as a partial oxidation furnace. In the apparatus shown in FIG. 9B, a boiler 3A is also provided in the combustion furnace 3 of the apparatus shown in FIG. 9A.

The combustible gas was supplied to the dust removing device 2 at 250 to 800 ° C., and the dust was removed by the candle-shaped ceramic filter and the honeycomb-shaped ceramic filter. Ceramic filters one _{_{may, S i0 2, A1 2 0}} 3, S i Kojiyuraito, an inorganic material similar composite, or that of these materials is a ceramic fiber-type or multi-porous type. To dislodge the dust removing apparatus 2, using nitrogen gas, 3~7kg / cm ^'2 pressure flicked, brushing 10 seconds to 20 minutes apart, was the brushing time from 0.05 to 15 seconds. This reduced the dust concentration from 1 to 5 g / Nm ³ before flowing into the P-remaining dust device 2 to 0.1 lg / Nm ³ or less. After removal of the removed dust, it was detoxified in a melting furnace and an incinerator. The combustible gas after dust removal was introduced into the wet gas treatment device 5, and the hydrogen chloride in the gas was reduced from 25 Oppm before treatment to 2 Oppm or less.

The combustible gas reduced in hydrogen chloride was heated to a temperature of 900 to 1100 ° C, which was burned in the combustion furnace 3. In the combustion furnace 3, a combustible gas was continuously burned by using a pilot burner (not shown) with a constant ignition source in order to avoid a danger such as an explosion. The output of this parner is tens of thousands to hundreds of thousands of kcal / h, and natural gas or kerosene was used as fuel. At this time, in both the boiler 4 installed downstream of Fig. 9A, the boiler 3A installed in the combustion furnace 3 of Fig. 9B, and the downstream boiler 4, heat recovery using 540 λl OOata steam can be performed. did it. Although stainless steel, Inconel and other alloy steels were used as boiler tubes, no significant corrosion was observed, and stable operation for more than one year was possible.

Claims

The scope of the claims

1. incompletely burning or partially oxidizing the waste in a partial oxidation furnace involving a combustion reaction to generate a combustible gas having an oxygen equivalent concentration of −30 to ^ at the outlet of the partial oxidation furnace;

Introducing the combustible gas to a dust remover at 250 to 800 ° C. to reduce the dust concentration to O.lg / Nm ³ or less;

Burning the combustible gas thus removed at a high temperature in a combustion furnace;

Waste treatment method having the following.

2. The method according to claim 1, wherein the combustible gas is introduced into the dust remover at 250 to 650 ° C to reduce the dust concentration to 0.1 lg / Nm ³ or less.

3. The method according to claim 1, wherein a filter-type dust collector is used as a dust remover, and dust attached to a filter of the dust collector is periodically wiped off with a gas having an oxygen concentration of ^ or less.

4. The method according to claim 1, wherein a filter-type dust collector is used as a dust removing device, and dust attached to a filter of the dust collector is periodically wiped off with nitrogen gas.

5. The method according to claim 3, wherein the temperature of the gas to be removed is equal to or higher than the temperature of the combustible gas.

6. The method of claim 4 wherein the temperature of the gas to be removed is equal to or higher than the temperature of the combustible gas.

7. The method according to claim 5, wherein gas for blowing off is blown when a differential pressure across the dust collector reaches a set value.

8. The method according to claim 6, wherein the gas for blowing off is blown when the differential pressure across the dust collector reaches a set value.

9. The method according to claim 7, wherein the dusted-off dust is burned with a gas containing oxygen at 400 to 750 ° C, and the gas generated by the burning is introduced into a partial oxidation furnace.

10. The method according to claim 8, wherein the removed dust is burned with a gas containing oxygen at 400 to 750 ° C, and the gas generated by the burning is introduced into a partial oxidation furnace.

1 1. The method according to claim 1, wherein an ignition source is provided in the combustion furnace to burn combustible gas continuously.

12. The method according to claim 1, wherein a poiler is provided in the combustion furnace or downstream of the combustion furnace, and heat is recovered by the poiler.

13. a process in which the waste is incompletely burned or partially oxidized in a partial oxidation furnace involving a combustion reaction to generate a combustible gas having an oxygen equivalent concentration of −30 to 1% at the partial oxidation furnace outlet; ,

Introducing the combustible gas into a dust remover at 250 to 800 ° C. to reduce the dust concentration to 0.1 lg / Nm ³ or less;

Introducing the combustible gas from which dust has been removed to a wet gas treatment apparatus to reduce the concentration of hydrogen chloride to 20 ppm or less;

Burning the combustible gas subjected to the wet gas treatment in a combustion furnace at a high temperature.

14. The method according to claim 13, wherein the combustible gas is introduced into the dust remover at 250 to 650 ° C to reduce the dust concentration to 0.1 lg / Nin ³ or less.

15. The method according to claim 13, wherein a filter-type dust collector is used as a dust remover, and dust attached to a filter of the dust collector is periodically wiped off with a gas having an oxygen concentration of 5% or less.

16. The method according to claim 13, wherein a filter-type dust collector is used as the dust remover, and dust attached to a filter of the dust collector is periodically wiped off with nitrogen gas.

17. The method according to claim 15, wherein the temperature of the gas to be removed is equal to or higher than the temperature of the combustible gas.

18. The method according to claim 16, wherein the temperature of the gas to be removed is equal to or higher than the temperature of the combustible gas.

19. The method according to claim 13, wherein an ignition source is provided in the combustion furnace to continuously burn combustible gas.

20. The method according to claim 13, wherein a boiler is provided in or downstream of the combustion furnace, and heat is recovered in the boiler.

21. a partial oxidation furnace that incompletely burns or partially oxidizes waste that produces combustible gas having an oxygen equivalent concentration of −30 to ^ at the furnace outlet;

A dust remover for reducing the dust concentration of the combustible gas at 250 to 800 ° C. to 0.1 lg / Nm ³ or less; a combustion furnace for burning the combustible gas removed at a high temperature;

Waste treatment equipment equipped with. '

22. A dust combustion furnace for burning dust blown off by the dust removing device and a conduit for guiding gas generated during the combustion to the partial oxidation furnace are provided.

23. The apparatus of claim 21 wherein the combustion furnace is provided with an ignition source.

24. a partial oxidation furnace that incompletely burns or partially oxidizes waste that generates combustible gas with an oxygen equivalent concentration of 30 to 1% at the furnace outlet;

A dust removing device for reducing the dust concentration of the combustible gas of 250 to 800 to 0.1 lg / Nm ³ or less; a wet gas treatment device for decreasing the concentration of hydrogen chloride of the combustible gas after the dust removal to 20 ppm or less;

A combustion furnace for burning the combustible gas subjected to the wet gas treatment at a high temperature;

Waste treatment equipment equipped with.

25. The apparatus of claim 24, wherein the combustion furnace is provided with an ignition source.