JP3276286B2 - Superheated steam production equipment using waste incineration heat - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of superheated steam by incinerating municipal refuse or industrial waste, producing steam by the heat of the combustion exhaust gas, and using the steam in a power plant or the like. .

[0002]

2. Description of the Related Art Conventionally, fluidized bed incinerators are often used as incinerators for incinerating waste such as municipal solid waste, and such apparatuses are accommodated on a dispersion plate (for example, a perforated plate) in a fluidized bed incinerator. The fluidized medium is fluidized and heated by blowing air or incineration exhaust gas etc. from below the dispersion plate into the fluidized medium such as sand, and waste such as municipal solid waste is thrown into the fluidized bed thus formed. Burn. The combustion gas generated by the combustion reaches a boiler via a combustion gas outlet line, generates steam by thermal contact with hot water in the boiler, and uses the steam as a turbine drive source of a power plant or the like.

[0003]

The waste such as municipal waste contains a chlorine-containing organic compound such as polyvinyl chloride plastic and the like.
Contains 5%. Chlorine contained in PVC plastics and the like mixed into waste such as municipal waste becomes HCl by combustion (usually, HC in municipal waste combustion exhaust gas).
1 is about 500 to 1000 ppm), which acts on the tube of the steam generating boiler installed downstream of the incinerator to corrode it. In particular, when the tube surface temperature is about 350 ° C. or higher, high-temperature corrosion becomes remarkable as the temperature increases. For this reason, conventionally, the tube surface temperature had to be 350 ° C. or less, and the temperature of the produced steam was limited to about 300 ° C. As a result, the power generation efficiency of conventional waste incineration is about 15
% Or less, and using fuel such as heavy oil or LNG containing almost no chlorine as fuel, which is remarkably lower than the power generation efficiency of a plant capable of setting the boiler tube temperature to 500 to 600 ° C. of about 40%, and its improvement has been strongly desired. .

[0004] In view of such technical problems, the present inventors provide an invention relating to the production of superheated steam capable of efficiently obtaining high-temperature, high-pressure superheated steam while preventing high-temperature corrosion of a boiler tube due to chlorine. It is in the thing. Another object of the present invention is to provide an invention relating to production of superheated steam capable of efficiently reducing chlorine and obtaining high-temperature superheated steam without using expensive high-grade materials as a boiler tube. Another object of the present invention relates to the production of superheated steam capable of efficiently performing the char combustion in the char combustion means and the pyrolysis in the pyrolysis means to be described later, efficiently reducing chlorine, and obtaining high-temperature superheated steam. It is to provide an invention.

[0005]

According to the first aspect of the present invention, the temperature is set to 30 degrees.
The waste is supplied to the space above 0 ° C and the thermal decomposition reaction is performed.
Pyrolysis gas and undecomposed residue generated by the reaction
The char mixture and the noncombustible
Pyrolysis means for separating the, extracted from the pyrolysis unit
Mixture consisting of separated undecomposed residue and flowing medium
While burning the undecomposed residue with air
Char combustion means for causing combustion of the pyrolysis gas;
Produce hot water or steam of about 400 ° C or less using lug
The first steam producing means to be produced and the char burning means.
With the obtained thermal energy, the first steam producing means
Second steam using the produced hot water or steam as superheated steam
It comprises manufacturing means, a flow which is heated from the char combustion means
A second char combustion means is interposed in the circulation path of the moving medium.
In the combustion medium of the second char combustion means.
Alternatively, a second steam producing means is provided.
Things. According to a third aspect of the present invention,
Akira supplies waste in a space with a temperature of 300 ° C or more to generate heat.
Decomposition reaction is performed and the pyrolysis gas generated by the reaction is
And a char mixture consisting of uncracked residue and fluidized medium
Pyrolysis means for separating the noncombustible material together, the pyrolysis hand
Consists of unresolved residue and fluidized medium removed from the stage
The char mixture is allowed to flow through the
Char burning means for burning the cracked residue, and the pyrolysis gas
Hot water of about 400 ° C or less
Or a first steam producing means for producing steam or steam .
The heat energy obtained by the combustion means makes the first steam
The hot water or steam produced by the steam production means is regarded as superheated steam.
A second steam producing means, wherein the char combustion means
A fluid medium path for returning the heated fluid medium to the pyrolysis means.
In the road, a heat head mitigation means including heat exchange means was provided.
A second char combustion means is interposed.
The more preferable temperature range of the supply waste is approximately 350 to 350.
At 500 ° C, produced by the thermal energy of the pyrolysis gas
The preferred temperature range of the hot water or steam to be produced is approximately 200 to 3
An apparatus which is 50 ° C. and which is used for the thermal decomposition means
For example, fluidized beds, rotary kilns, screw agitators
Examples of the char combustion means such as a stirring tank include a bubble fluidized bed,
A fast fluidized bed and the like can be mentioned.

According to this invention, for example, as shown in FIG. 3, waste such as municipal waste is pyrolyzed, for example, even if it is a chlorine-containing pyrolysis gas containing HCl or the like in the pyrolysis gas. The heating of the boiler water by the thermal energy of the chlorine-containing pyrolysis gas has a substantially boiling point of about 200 ° C. to 320 ° C. Therefore, even if the chlorine-containing pyrolysis gas acts on the tube of the steam generating boiler, the tube is heated. Since the surface temperature does not exceed about 350 ° C., it does not corrode. In this case, the boiler water has a boiling point of approximately 200 ° C. to 32
Since the temperature is set at about 0 ° C., even if the application of thermal energy to the boiler water of the chlorine-containing pyrolysis gas varies, it is absorbed by the latent heat of the boiler water (in other words, the phase conversion from water to steam). Is used only for the boiler water and does not act as a temperature rise), so that the boiler water or steam at a stable heating temperature is obtained without the surface temperature of the heat exchange tube of the boiler water rising above the chlorine corrosion temperature. I can do things.

The undecomposed residue which has not been decomposed by the thermal decomposition at about 300 ° C. to 500 ° C. has already been dechlorinated.
Approximately 200 ° C. using heat energy of about 950 ° C.
Even if boiler water or steam that has been primarily heated to about 320 ° C. is subjected to secondary to tertiary heating to obtain heated steam of 400 to 500 ° C. (boiler tube temperature is about 450 to 550 ° C.), there is no possibility that tube corrosion will occur. . As a result, even when power is generated by incineration of garbage, 30 to 4 fuel cells, such as heavy oil or LNG, containing almost no chlorine, are used.
0% power generation efficiency can be obtained.

[0008]

[0009]

The invention according to claims 2 and 4 is characterized in that the steam heated by the first or second steam producing means or a part of the hot water or steam introduced into any of the producing means is subjected to the char combustion. The steam is heated by appropriately introducing the heat into the heat exchange means disposed on the high temperature side of the means.

[0011]

[0012]

According to a fifth aspect of the present invention, the temperature is 300 ° C. or more.
The waste is supplied to the space to cause a thermal decomposition reaction,
Gas, undecomposed residue and stream generated by the reaction of water
Separation of char mixture consisting of moving medium and incombustible material from each other
Pyrolysis means that, unfractionated taken out from the pyrolysis unit
The char mixture consisting of the decomposed residue and the flowing medium is
Therefore, a chamber for burning the undecomposed residue while flowing
And over the combustion unit, the incombustible extraction discharged effluent from outlet of the pyrolysis means to separate the large incombustible and other emissions, the first for feeding the other exudates to the char combustion means bottom side Filter means, and second filter means for separating the small incombustibles and the fluid medium with respect to the discharge discharged from the incombustible material outlet of the combustion means, and feeding the fluid medium to the bottom side of the char combustion means, Further, if necessary, the second
And a third filter means for separating ash and feeding the ash-separated fluid medium to the bottom side of the char combustion means at the outlet side of the filter means.

It is necessary that the first filter means has a mesh size larger than at least the second filter means. More specifically, the first filter means depends on the size of waste to be charged. About 5 mm, and the second filter means is 2 m larger than the maximum diameter of the flowing medium (about 1.0 mm).
It is better to set it to around m. The third filter means is preferably set to about 0.1 mm which is smaller than the minimum diameter (about 0.2 mm) of the fluid medium. Further, for example, a vibration sieve or the like can be used as the filter means.

[0015] Since the char mixture separated by pyrolyzing means even in the any of the claims according to the invention of such claims 1-5, wherein not included in the chlorine substantially, the second steam producing this Even if it is used as a superheat source of the means to obtain superheated steam of 500 ° C. or more, high-temperature corrosion of equipment does not occur.

As the heating source of the first steam producing means, a combustion exhaust gas of a pyrolysis gas containing chlorine is used, but the heat is utilized to be about 400 ° C. or less, specifically, about 200 to 320 ° C.
In order to produce only the following hot water or steam, to heat only below the temperature of hot corrosion,
There is no danger of corrosion of boiler tubes and the like, and there is no need to use expensive high-grade materials.

In the invention described in claim 2 or 4 , the steam heated by the first or second steam producing means or a part of the hot water or steam introduced into any one of the producing means is subjected to the combustion. It is characterized in that it is appropriately introduced into heat exchange means (hereinafter referred to as first heat exchange means) arranged on the high temperature side of the means.

That is, since the char combustion means burns the undecomposed residue while flowing the char mixture with air, the combustion gas has a high temperature, specifically 700 ° C.
It reaches 950 ° C.

Therefore, the high-temperature gas is used to exchange heat with the steam heated by the first or second steam producing means or a part of the hot water or steam introduced into any of the producing means. The following functions can be performed.

That is, the hot water introduced into the first steam producing means may be introduced into the heat exchange means to raise the temperature to a certain extent, or the hot water introduced into the second steam producing means may be heated. Alternatively, by introducing steam in parallel with the first steam producing means to the heat exchanging means, the amount of heating of the second steam producing means can be increased, and a large amount of superheated steam can be obtained.

Further, the high temperature side of the char combustion means is 8
Since the heated superheated steam is heated to 00 to 950 ° C., the superheated steam heated by the second steam producing means is introduced into the heat exchanging means to obtain a further heated superheated steam of, for example, 400 to 520 ° C. And a sufficiently heated superheated steam can be obtained. Therefore, the first and second steam producing means, the second steam producing means, and the first heat exchanging means were used to increase the temperature substantially in series / parallel in a multi-step manner, so that a large amount and sufficient heat were obtained. Superheated steam can be obtained.

The provision of the heat exchange means on the high-temperature area side of the char combustion means means that when the high-temperature area, which is unnecessarily high at 950 to 1300 ° C., is allowed to flow to the outlet line as it is, the temperature of ordinary refractory material becomes high. To 800-950 ° C
The normal refractory line can be used. Further, even if the temperature is lowered to 800 to 950 ° C as described above, the steam temperature in the second steam producing means is set to 400 to 520 ° C.
There is no hindrance in maintaining it.

On the other hand, the temperature of the fluid medium heated by the char combustion means also becomes high. Therefore, as in the first aspect of the present invention, the second char combustion means is interposed in the circulation path of the fluid medium heated by the char combustion means by utilizing the high temperature fluid medium, and the second char combustion means is provided. It is preferable that the first or second steam producing means or the heat exchange means according to claim 3 is disposed in the combustion medium of the char burning means on the high temperature side of the char burning means. Thereby, the first
A large amount of sufficiently heated superheat by substantially multi-stage heating in series / parallel using the steam producing means, the second steam producing means, and the first and second heat exchanging means. You can get steam. Therefore, liquidity medium stable high temperature is obtained by the heat capacity is large thermal contact.

The fluid medium of the char combustion means circulates between the pyrolysis means. The temperature of the fluid medium of the char combustion means is approximately 700 to 850 ° C. The temperature is 350 to 500 ° C., and the heat drop between the two is large. Therefore, when the fluid medium of the char combustion means is directly introduced to the pyrolysis means side, the heat drop increases the pyrolysis temperature in the pyrolysis means. Or heat fluctuations may occur, thus complicating the adjustment of the amount of the fluid medium to be returned.

Therefore, as in the third aspect of the present invention, a thermal head mitigation means, preferably a heat exchange means, is provided in the fluid medium path for returning the fluid medium heated by the char combustion means to the thermal decomposition means. Preferably, a second char combustion means is interposed. Thereby, the same effect as the first aspect of the invention is obtained by the second char combustion means, and for example, the fluid medium heated to 700 to 850 ° C. by the first char combustion means is cooled by the second char combustion means. The temperature is lowered to 500 to 700 ° C by heat removal by the heat exchange means.
Since the fluidized medium dropped to 00 ° C. can be returned to the pyrolysis means, a gentle thermal gradient is possible. As a result, the pyrolysis temperature in the pyrolysis means is increased from 350 ° C. to 500 ° C.
Control is possible stably before and after. It is preferable to use a superheater or a boiler for the first and second heat exchange means.

According to a fifth aspect of the present invention, generally about 200 mm of waste is introduced into the thermal decomposition means as waste. It is necessary to increase the diameter of the discharge port to some extent, so that some char residue and a fluid medium such as sand are taken out of the discharge port in addition to the non-combustible material. Therefore, the first filter means separates large incombustibles and other exhausts from the exhausts discharged from the incombustible material outlet of the thermal decomposition means, and discharges only large incombustibles. Is intended to be fed to the bottom of the combustion means and used for combustion.

Further, since the large incombustibles have already been removed from the char burning means and the char residue has been sufficiently burned, the exhaust discharged from the incombustible material outlet is small incombustible. Only the material and the fluid medium need to be separated by the second filter means. By feeding the separated fluid medium to the bottom side of the combustion means, loss of the fluid medium can be prevented, and circulating reuse can be performed. Although the third filter means is not always necessary, it discharges only the ash to the outside while supplementing the fluid sand not supplemented by the second filter means, so that efficient ash removal and fluid sand can be achieved. Recovery becomes easier.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. It's just FIG.
1 shows a superheated steam production apparatus using the heat of incineration of waste according to an embodiment of the present invention. In the drawing, reference numeral 1 denotes a pyrolysis furnace comprising a fluidized bed, and And the like. Fluid medium and waste such as municipal solid waste are supplied from a waste supply line 4 and a sand circulation (return) line 5, and the combustion supplied from a combustion exhaust gas inlet line 6. Exhaust gas, etc. (This pyrolysis furnace is basically for the purpose of pyrolysis rather than combustion, so the supplied gas is mostly combustion exhaust gas that consumes oxygen. A small amount) to generate a fluidized bed space at a temperature of 300 ° C. or higher, and to cause a pyrolysis reaction of the waste. The pyrolysis gas generated by the reaction is supplied from a pyrolysis gas outlet line 7 to the undecomposed residue Char mixture consisting of sand removes the char mixture From line 9, incombustible than incombustible material withdrawal line 8, taken in isolation, respectively from each other.

At this time, it is desirable to carry out the thermal decomposition so that the thermal calorie ratio of the pyrolysis gas and the char mixture becomes "about 7 (pyrolysis gas): about 3 (char mixture)". This is because when the boiler water to be heated is pressurized to about 100 kgf / cm ² , the boiling point becomes about 309 ° C. Therefore, with the pyrolysis gas, the boiler water is cooled to room temperature by the water-cooled wall boiler 36 and the first boiler 24. More specifically, the ratio of the calorie that rises until almost vaporized at 309 ° C. and the calorie that rises the raised steam from 309 ° C. to 500 ° C. at about 309 ° C. is about 7: 3. It depends.

An air inlet line 21 A is attached to the pyrolysis gas outlet line 7 on the outlet side of the pyrolysis furnace 1, and the pyrolysis gas extracted from the pyrolysis furnace 1 is introduced into the air through the air inlet line 21. If necessary, tar and the like contained in the pyrolysis gas are partially burned to prevent tar adhesion and caulking in the outlet line 7.
At the downstream end of the outlet line 7, a pyrolysis gas combustion furnace 34 composed of a combustion duct is provided, and sufficient air is supplied to the pyrolysis gas from a line 21 'to complete combustion of the pyrolysis gas. Do.

Reference numeral 10 denotes a char combustion furnace composed of a bubble fluidized bed furnace. The char mixture is supplied from a char mixture take-out line 9 onto a dispersion plate 11 disposed at the bottom of the char combustion furnace, and a sand circulation line 19-2 / 19-1. The fluidized sand circulated between the auxiliary char combustion furnace 10B is stored. Then, air is supplied from an air supply line 12 below the dispersion plate 11 and is heated to 700 to 800 ° C. in the fluidized bed 2-3 to burn undecomposed residues. Air is introduced from the line 13 and burns further to about 800-
A combustion gas of about 1300 ° C. is generated, and a second superheater 29-1 is disposed in an upper region of the char combustion furnace 10 to provide a second steam production means (first superheater 20).
Along with the superheating of the superheated steam introduced through the line 28-1, the combustion gas, which has become unnecessarily high around 950 to 1300 ° C, is dropped to 800 to 950 ° C. As described above, even if the combustion gas temperature is lowered to 800 to 950 ° C., there is no problem in maintaining the steam temperature in the first superheater 20 at 200 to 320 ° C. And the char combustion furnace 1
Small incombustibles that are not burned at 0 are taken out from the incombustibles take-out line 14.

On the other hand, the char combustion furnace 10 is provided with a sub-char combustion furnace 10B as a sub-fluidized bed, as shown in FIGS. 1 and 2, through a sand circulation line 19-2 / 19-1. Liquid sand is configured to flow between the auxiliary char combustion furnace 10B, and a third superheater 29-2 is disposed in the flowing medium of the auxiliary char combustion furnace 10B, and an outlet of the second superheater 29-1 is provided. Side and a line 28-2. The auxiliary char combustion furnace 10B may be provided independently as shown in FIG. 2, but the fluid medium heated from the char combustion furnace 10 is returned to the pyrolysis furnace 1 as shown in FIG. It is preferable to interpose a sub-char combustion furnace 10B provided with a third superheater 29-2 in the fluid medium path 19-1 / 5.

The combustion gas heat-exchanged by the second superheater 29-1 is introduced from a sand / combustion gas outlet line 15 to a gas / solid separation device, for example, a cyclone 16, as required, where the dust and ash are removed. The combustion gas is separated from the combustion gas, and the combustion gas is introduced into the first superheater 20 through the gas outlet line 17.

Reference numeral 20 denotes a first superheater and reference numeral 24 denotes a first boiler. In the first boiler 24, the pyrolysis gas extracted from the pyrolysis gas outlet line 7 is supplied to a combustion gas combustion furnace 34 in which a water-cooled wall boiler 36 is installed. The boiler water introduced into the first boiler 24 and taken in from the boiler water inlet 26 together with the combustion exhaust gas discharged from the boiler gas outlet 22 of the first superheater 20 through the boiler gas outlet 22 is heated to about 300 ° C. 1st superheater 2 from boiler outlet line 27
Supply steam or heated water to zero.

The boiler water is also introduced into a water wall boiler 36 in a combustion gas combustion furnace 34 through a branch line 26 ', and supplies steam or heated water to the first superheater 20 through a branch line 27'. The boiler water, which is pressurized to about 100 kgf / cm ² and its boiling point is set at about 309 ° C., is introduced into the water-cooled wall boiler 36 and the first boiler 24 to perform the first-stage heating. However, the flow rate of water is controlled so that the heating temperature is about 309 ° C., which is near the boiling point.

As a result, the tube surface wall temperature of the water-cooled wall boiler 36 and the first boiler 24 can be maintained at 350 or less following the heated water, and for example, the heat-exchanged pyrolysis gas contains chlorine or HCl. No corrosion will occur.

In the first superheater 20, steam / heated water taken out from the outlet lines 27 and 27 'of the first boiler 24 and the water-cooled wall boiler 36, and heated by the water-cooled wall boiler 36 and taken out through a branch steam line 27'. The heated steam / heated water is introduced and heated by the combustion gas supplied through the combustion gas line 17 to produce superheated steam.
1 and a third superheater 29- from line 28-2.
The superheated steam which is introduced in series into each of 2 and superheated to 400 to 520 ° C. is taken out and sent to the generator.

Although the operation of the above embodiment has been described together with the configuration, the explanation will be briefly repeated. A chlorine-containing organic compound such as PVC plastic is mixed in the waste such as municipal solid waste supplied to the pyrolysis furnace 1. It contains about 0.2 to 0.5% as Cl in combustibles. Then, municipal solid waste from the waste supply line 4 and high-temperature circulating fluidized sand from the fluidized sand circulation line 5 are supplied to the pyrolysis furnace 1, respectively, and the temperature is slightly adjusted to the combustion air from the lower air or the combustion exhaust gas inlet line 6. By treating at a temperature of 350 to 500 ° C. in a fluidized bed in which the fluidized sand 2-1 is fluidized by supplying air for use, an undecomposed residue substantially free of chlorine is obtained from the char mixture removal line 9. Can be That is, substantially all of the chlorine contained in the waste is contained in the pyrolysis gas and discharged to the pyrolysis gas outlet line 7. The large-sized incombustibles separated by the thermal decomposition reaction in the thermal decomposition furnace 1 are taken out of the furnace through an incombustibles take-out line 8. At this time, the pyrolysis time and the pyrolysis temperature are set so that the thermal calorie ratio of the pyrolysis gas and the char mixture becomes 7: 3.

The pyrolysis gas extracted from the pyrolysis outlet line 7 of the pyrolysis furnace 1 contains gas, oil, tar, and HCl. Preliminary combustion is performed with the supplied air to prevent the temperature from lowering, while preventing tar adhesion and coking at the outlet line 7 and introducing air into the pyrolysis combustion furnace 34 further from the line 21 ′. Perform complete combustion within. As a result, since the temperature of the pyrolysis gas in the pyrolysis combustion furnace 34 can be set high, the water-cooled wall boiler 36
-1, 36-2 and a boiling point of 20 introduced into the first boiler 24
It is possible to produce a large amount of steam / boiler water which rises to about 0 to 320 ° C.

The water-cooled wall boiler 36 in the pyrolysis combustion furnace 34
-1 is supplied to the first boiler 24 from the first boiler gas inlet 23 together with the flue gas from the first superheater boiler gas outlet line 22. Since the gas introduced into the pyrolysis combustion furnace 34 and the first boiler 24 contains about 500 to 1000 ppm of HCl, the flow rate of the boiler water is adjusted to adjust the water cooling wall boiler 36 and the first boiler 24. The surface temperature of the tube is set to about 350 ° C. or less, which is the same as the conventional one, to suppress high temperature corrosion. For this reason, the water-cooled wall boilers 36-1, 36-2 and the first boiler 2
In No. 4, high temperature superheated steam cannot be obtained, but about 300 to 32
Since it can be heated to 0 ° C., if it is further heated by the super heaters 29-1 and 29-2 after the first super heater 20, a high-temperature superheated steam of about 500 to 700 ° C. can be obtained.

The char mixture taken out from the char mixture take-out line 9 in the pyrolysis furnace 1 is composed of fluidized sand and uncracked residue, and is substantially free of chlorine.
In the combustion furnace 10, the air is supplied to a lower part of the combustion furnace 10 and is burned by air supplied from an air supply line 12 through a dispersion plate 11. In this case, the amount of air supplied from the air supply line 12 is adjusted, and the undecomposed residue is burned while flowing the fluidized sand. Air supply line 1 for complete combustion
Further air may be supplied from 3 and 19-3. The temperature of the combustion furnace 10 rises due to a combustion exothermic reaction. This temperature value is determined by the calorific value of the undecomposed residue supplied from the char mixture removal line 9, the amount of air in the air supply lines 12, 13 and the amount and temperature of the fluidized sand in the sand circulation lines 19-1, 19-2. , 1000 to 1200 ° C.

Then, the second superheater 29-1 exchanges heat with the superheated steam from the first superheater 20 via the line 28-1 to reduce the combustion gas to 800 to 950.
It is easy to reach ° C. A water-cooled wall boiler 36-2 for heating the boiler water circulated by the lines 26 ", 27" branching off the lines 26, 27 instead of the first superheater 20 or together with the first superheater 20 as necessary.
May be provided. Incombustibles that have been miniaturized by melting glass, cans and the like are extracted from the incombustibles take-out line 14.

The sub-char combustion furnace 10B may be provided independently as shown in FIG.
Is circulated between the thermal decomposition furnace 1 and the temperature of the fluid medium of the char combustion furnace 10 is approximately 700 to 850 ° C., while the temperature of the fluid medium of the thermal decomposition furnace 1 is 350 to 400 ° C. Since the heat drop between the two is large, the char combustion furnace 10
If the fluid medium is directly introduced into the pyrolysis furnace 1, the thermal head may increase the pyrolysis temperature or cause thermal fluctuations in the pyrolysis furnace 1, and therefore, adjust the amount of the fluid medium returned. Is complicated.

Therefore, as shown in FIG. 1, the third superheater 2 is provided in the flowing medium path 19- ／ for returning the flowing medium heated from the char combustion furnace 10 to the pyrolysis furnace 1.
By interposing the sub-char combustion furnace 10B provided with 9-2, the fluid medium heated to 700 to 800 ° C. in the first char combustion furnace 10
500-700 due to heat removal by super heater 29-2
C., and the fluid medium dropped to 500 to 700 ° C. can be returned to the pyrolysis furnace 1, so that a gentle thermal gradient is possible. As a result, the pyrolysis temperature in the pyrolysis furnace 1 is reduced to 350 ° C. It is possible to stably control the temperature from about 500C to about 500C. 28-3 is a superheated steam take-out line, and 12 'is an air supply line.

On the other hand, 800-9
Combustion gas at a high temperature of 50 ° C. and substantially free of chlorine is introduced into a cyclone 16 as needed via a combustion gas outlet line 15, and dust and ash are discharged from an outlet line 18.
The exhaust gas is separated and taken out from each of the gas outlet lines 17.

On the other hand, the high temperature exhaust gas of 800 to 950 ° C. taken out of the gas outlet line 17 of the cyclone 16 is introduced into the first superheater 20 and the first boiler 24
And it is used for heating steam / boiler water at about 200 to 320 ° C. produced by the water-cooled wall boiler 36 to produce superheated steam. Since the exhaust gas passing through the gas outlet line 17 does not substantially contain chlorine, the first superheater 20
Even when the surface temperature of the boiler tube is set to 350 ° C. or higher, high-temperature corrosion is greatly reduced. Therefore, the temperature of the fluid in the tube can be set to about 400 to 520 ° C., and high-temperature superheated steam can be stably obtained from the first superheater boiler steam outlet 28-1.

In order to maintain the temperature of the pyrolysis furnace 1 at a predetermined temperature of 300 ° C. or higher in the pyrolysis furnace 1, the amount of oxygen in the flowing gas supplied from the flue gas inlet line 6 is adjusted, in other words, the first boiler A small amount of air is supplied together with the combustion exhaust gas from the combustion chamber 24, and a part of the fluidized sand at a high temperature of about 500 to 700 ° C.
And heat source.

For example, air or combustion exhaust gas supplied to the pyrolysis furnace 1 from the combustion exhaust gas inlet line 6 is 350 to 5
In order to efficiently perform pyrolysis in the range of 00 ° C, a combustion exhaust gas containing a small amount of oxygen (about 3 to 5%) and maintaining a temperature of 150 to 200 ° C, specifically, a first boiler It is preferable to use the combustion exhaust gas taken out from the 24 outlet lines 25. In addition, in each figure, 11, 3-1, 3-2
Denotes a dispersion plate, and 2-1 and 2-2 and 2-3 denote fluidized beds.

FIG. 4 shows an apparatus for producing superheated steam using the heat of incineration of waste according to another embodiment of the present invention.
In order to explain the difference from this embodiment, a first filter 291 such as a vibrating sieve having a mesh diameter of about 5 mm is provided in the incombustibles removal line 8 of the pyrolysis furnace, and the first filter 291 is discharged from the line 8. It is configured to separate large incombustibles and other effluents from the effluent, and feed the other effluent to the bottom of the fluidized bed above the dispersion plate 11 of the char combustion furnace 10 via the lines 50 and 54. are doing. Reference numeral 51 denotes a large incombustible substance take-out line.

On the other hand, small incombustibles and the like that are not burned in the char combustion furnace 10 are taken out from the incombustibles take-out line 14. A second filter 292 having a mesh of about 2 mm is interposed in the incombustibles removal line 14 to separate small incombustibles from fluidized sand and ash from the discharged material from the line 14, and to remove fluidized sand into a line 52. , The third filter 29
3. It is configured to feed to the fluidized bed bottom side above the dispersion plate 11 of the char combustion furnace 10 via lines 55 and 54. The small incombustibles are discharged from the line 53 to the outside.

The third filter 293 is not necessarily required, but discharges only the ash to the outside while supplementing the fluidized sand not captured by the second filter 292. 0.2 mm), which is set to about 0.1 mm. Thereby, the third filter 2
At 93, only the ash can be discharged to the outside via the line 56 while supplementing the fluid sand not captured by the second filter 292, thereby facilitating efficient ash removal and recovery of the fluid sand. .

Next, the operation of the above embodiment will be described in detail.
The large-sized incombustibles separated by the thermal decomposition reaction in the thermal decomposition furnace 1 are taken out of the furnace through an incombustibles take-out line 8.
Generally, about 200 mm of waste is introduced into the pyrolysis furnace 1 as waste. For this reason, the diameter of the non-combustible material take-out line 8 of the pyrolysis furnace 8 must be increased to some extent. In addition to non-combustible materials larger than 8, char residue, fluidized sand, and small non-combustible materials are taken out. Therefore, the first filter 291 separates large-sized incombustibles from other exhausts from the incombustibles take-out line 8 of the pyrolysis furnace 1 and discharges only large-sized incombustibles. The material can be fed to the bottom side of the char combustion furnace 10 and used for combustion.

In the char combustion furnace 10, miniaturized incombustible substances such as glass fragments and iron swarf are extracted from an incombustible substance extraction line 14. On the other hand, since the large incombustibles have already been removed from the char combustion furnace 10 and the char residue has been sufficiently burned, the exhaust discharged from the incombustibles removal line 14 is small incombustibles. And second only liquid sand
And the liquid sand separated by the filter 292 and the third filter 293.
By feeding the fluidized sand to the bottom side of the fluidized bed of the combustion furnace 10 via / 54, only the fluidized sand can be circulated and reused.

[0054]

As described above, according to the present invention, when waste is burned to obtain superheated steam without using expensive high-grade materials, it is possible to prevent high-temperature corrosion of the boiler tube by chlorine while preventing high-temperature and high-pressure corrosion. Superheated steam can be obtained efficiently. ADVANTAGE OF THE INVENTION According to this invention, the removal of incombustible substances and the separation of the fluid medium in the waste pyrolysis means and the char combustion means can be performed more efficiently, and stable pyrolysis and char combustion can be performed. And so on.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an apparatus for producing superheated steam using heat of waste incineration according to a first embodiment of the present invention.

FIG. 2 is a system diagram showing an apparatus for producing superheated steam using waste heat of incineration according to a second embodiment of the present invention.

FIG. 3 is a graph showing a procedure for producing superheated steam using the heat of incineration of waste according to the basic configuration of the present invention.

FIG. 4 is a system diagram showing a superheated steam production apparatus using waste heat of incineration according to a second embodiment of the present invention.

[Description of Signs] 1 Pyrolysis furnace (pyrolysis means) 10 Combustion furnace (char combustion means) 11 Dispersion plate 20 First superheater (second steam production means) 29-1 Second superheater (second steam production means) 20-2 Third superheater (second steam producing means) 24 First boiler (first steam producing means) 34 Pyrolysis gas combustion furnace 36 Water-cooled wall boiler (first steam producing means) 31 Ash melting furnace 291 First filter means 292 Second filter means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI F23G 5/30 ZAB F23G 5/30 ZABH (72) Inventor Shizuo Yasuda 12 Nishikicho, Naka-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. (72) Inventor Yuji Kaihara 12 Nishikicho, Naka-ku, Yokohama-shi Yokohama Heavy Industries, Ltd. (56) References JP-A-5-346204 (JP, A) JP-A-58-95104 (JP, A) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) F23G 5/48 F22B 1/18 F22G 1/16 F23G 5/027 F23G 5/30

Claims (5)

(57) [Claims] (1)Provide waste in a space with a temperature of 300 ° C or higher.
To cause the thermal decomposition reaction, which is generated by the reaction
Char consisting of pyrolysis gas, uncracked residue and flowing medium
Pyrolysis means for separating the mixture and incombustibles from each other, Undecomposed residue and fluid removed from the pyrolysis means
Do not allow the char mixture consisting of the medium to flow with air.
Char burning means for burning the undecomposed residue, Approximately 400 using the combustion heat energy of the pyrolysis gas
First steam production means for producing hot water or steam at a temperature of not more than ℃
When, The heat energy obtained by the char combustion means causes
The hot water or steam produced by the first steam production means
A second steam producing means for producing hot steam, Circulation path of fluid medium heated by the char combustion means
A second char combustion means interposed therein, and the second char
The first or second steam in the combustion medium of the combustion means;
Utilizes the heat of incineration of waste, characterized by the provision of manufacturing means.
Superheated steam production equipment used. 2. The method according to claim 1, wherein the first or second steam producing means is used.
Introduced into heated steam or any of the above manufacturing means
A portion of the hot water or steam that is
Into the heat exchange means located on the high temperature side of the
2. The method according to claim 1, wherein the heating is performed.
Superheated steam production equipment using the heat of incineration of waste. (3)Provide waste in a space with a temperature of 300 ° C or higher.
To cause the thermal decomposition reaction, which is generated by the reaction
Char consisting of pyrolysis gas, uncracked residue and flowing medium
Pyrolysis means for separating the mixture and incombustibles from each other, Undecomposed residue and fluid removed from the pyrolysis means
Do not allow the char mixture consisting of the medium to flow with air.
Char burning means for burning the undecomposed residue, Approximately 400 using the combustion heat energy of the pyrolysis gas
First steam production means for producing hot water or steam at a temperature of not more than ℃
When, The heat energy obtained by the char combustion means causes
First steam production means Through the hot water or steam produced in
A second steam producing means for producing hot steam, The fluid medium heated by the char combustion means is thermally decomposed.
In the fluidized medium path returning to the stage, consist of heat exchange means etc.
The second char combustion means provided with the thermal head mitigation means is interposed.
Superheated steam using the heat of incineration of waste
Qi production equipment. 4. The steam heated by the first or second steam producing means or a portion of hot water or steam introduced into any one of the producing means is disposed on a high temperature side of the char combustion means. The steam is introduced into the heat exchange means and
The apparatus for producing superheated steam using waste incineration heat according to claim 3, wherein the apparatus is heated. Claim 5.Provide waste in a space with a temperature of 300 ° C or higher.
To cause the thermal decomposition reaction, which is generated by the reaction
Char consisting of pyrolysis gas, uncracked residue and flowing medium
Pyrolysis means for separating the mixture and incombustibles from each other, Undecomposed residue and fluid removed from the pyrolysis means
Do not allow the char mixture consisting of the medium to flow with air.
Char burning means for burning the undecomposed residue, Emissions discharged from the incombustibles outlet of the pyrolysis means
Separation of large incombustibles and other emissions from materials and other emissions
A first filter hand for feeding material to the bottom side of the char combustion means
Steps and Emissions discharged from the incombustible material outlet of the combustion means
About the small incombustibles and the fluid medium,
A second filter means for feeding to the bottom side of the char combustion means;
Provided, Further, if necessary, on the outlet side of the second filter means,
Separates the ash and uses the fluid medium after the ash separation as char combustion means.
Third filter means for feeding to the bottom side; The use of waste incineration heat
Hot steam production equipment.