JPH09170735A - Heating method of pyrolytic reactor in waste treatment equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide equipment, employing a heat source, having no corrosive property, to heat heating air for a pyrolytic reactor furnace and even of combustion gas is employed for the heat source, the amount of the same is small and the heat transfer area thereof is small whereby the miniaturization of the device as well as the reduction of construction cost can be contrived. SOLUTION: A device is constituted so that distillated gas G1 and pyrolytic residue (c) are produced in a pyrolytic reactor 2, then, they are separated in a discharging device 9 and the pyrolytic residue (c) is cooled to separate them into combustible constituent and incombustible constituent and treat the distillated gas G2 and the combustible constituent in the combustion furnace 10 through combustion. In this case, combustion gas in the furnace 10 is supplied to a waste heat boiler 4 to generate steam S, the steam S is supplied to a first air heater 3 to heat low-temperature heating air (b'), discharged out of the pyrolytic reactor 2, in the first air heater 3 and, thereafter, the heating air (b') is heated in a second air heater 5 to supply it into the pyrolytic reactor 2 as high-temperature hearing air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for heating a pyrolysis reactor in a waste treatment apparatus, and more particularly, to put the waste into a pyrolysis reactor and heat it with heated air to pyrolyze it for dry distillation gas. And pyrolysis residue are generated, the pyrolysis residue is separated into combustible components and non-combustible components, and the carbonization gas and the combustible components are supplied to a combustor for combustion treatment. The present invention relates to a method for heating a pyrolysis reactor in a waste treatment device.

[0002]

2. Description of the Related Art As one of the industrial waste treatment devices containing general waste such as municipal waste and combustibles such as waste plastic, the waste is put into a thermal decomposition reactor and the inside of the thermal decomposition reactor is Under atmospheric pressure (negative pressure), it is heated by a heating fluid flowing in the heat transfer tube to be pyrolyzed to produce a dry distillation gas and a pyrolysis residue mainly composed of non-volatile components, and further the pyrolysis residue is cooled. After that, a combustible component mainly composed of carbon and a non-combustible component composed of rubble such as metal, pottery, gravel, concrete pieces, etc. are separated by a separating device, and the combustible component is crushed. The components and the carbonized gas are introduced into a melting furnace, which is a combustor, and subjected to combustion treatment. The resulting combustion ash is made into molten slag, and the molten slag is discharged and solidified by cooling. Then, the waste is heated in the pyrolysis reactor to be pyrolyzed, and the low-temperature heating air is heated by the combustion gas from the melting furnace and becomes high-temperature heating air so that it is supplied to the pyrolysis reactor. The waste treatment apparatus configured as described in JP-A-64-49816 and DE-A-3815187 is proposed.

[0003]

By the way, according to the heating method of the thermal decomposition reactor in the waste treatment apparatus as described above, the low temperature heated air discharged from the thermal decomposition reactor is heated and raised by the combustion gas. However, there is a problem in that a large heat transfer surface is required, which increases the construction cost.

That is, since this combustion gas has a corrosive property, the high temperature combustion gas cannot act on the air heater for heat exchange from the viewpoint of corrosion resistance and heat resistance.
As a result, there is a problem that a wide heat transfer surface is inevitably required.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, in which waste is put into a thermal decomposition reactor and heated by heated air for thermal decomposition. Then, a pyrolysis product consisting of the dry distillation gas and the pyrolysis residue is produced, and the dry distillation gas and the pyrolysis residue are separated in an exhaust device, and after the pyrolysis residue is cooled, a combustible component and In a waste treatment device that is separated into non-combustible components and supplies the dry distillation gas and the combustible components to a combustion furnace for combustion treatment, the combustion gas in the combustion furnace is supplied to a waste heat boiler. To generate steam, and this steam is
Of the low temperature heating air which is supplied to the air heater of No. 1 and is discharged from the pyrolysis reactor is heated by the first air heater and then heated by the second air heater to heat the high temperature. It is intended to provide a method for heating a pyrolysis reactor in a waste treatment device, which is air and is configured to supply this high-temperature heated air to the pyrolysis reactor.

The second air heater is heated by the combustion gas generated by any one of the heat transfer heater, the oil fire, and the combustor. According to the method for heating the pyrolysis reactor in such waste, the low-temperature heating air discharged from the pyrolysis reactor is first heated by the steam from the waste heat boiler in the first air heater, and then heated. The second air heater heats and raises the temperature to a predetermined high temperature. Therefore, even if the combustion gas is supplied to the second air heater to heat and raise the temperature of the heated air, the heat transfer area is small, and as a result, the waste treatment device can be manufactured at low cost.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for heating a thermal decomposition reactor in a waste treatment apparatus according to the present invention will be described below with reference to FIG. In FIG. 1, reference numeral 1 denotes a waste supply device that supplies waste a containing combustibles such as municipal waste into the pyrolysis reactor 2. A horizontal rotary drum is usually used for the thermal decomposition reactor 2, the inside of which is kept under atmospheric pressure (negative pressure) by a sealing mechanism (not shown), and at 300 ° C. by heated air b supplied from the line L _1. 600
° C., usually is heated to about 450 ° C., the entered waste a is heated by the heated air b, generate a carbonization gas G ₁ is thermally decomposed, and the pyrolysis residue c consisting mainly of non-volatile components To be done.

More specifically, the heating air b supplied from the downstream side of the thermal decomposition reactor 2 via the line L ₁ is usually 52
The heating air b has a high temperature of about 0 ° C., and the heating air b having a high temperature moves in a space outside the heat transfer tube while flowing through a heat transfer tube (not shown) provided in the pyrolysis reactor 2. The waste a is indirectly heated and becomes low temperature heated air b'of, for example, about 270 ° C., which is discharged from the upstream side and supplied to the first air heater 3 via the line L ₂ .

With respect to the first air heater 3, a waste heat boiler 4 provided in the latter stage of the melting furnace 10 which constitutes a combustor.
The steam S at a temperature of about 400 ° C. obtained by recovering the heat in the above is supplied, and the low temperature heated air b ′ is heated to a temperature of about 350 ° C. to 380 ° C.
The heated air b ″ having a relatively low temperature of about ℃ flows into the second air heater 5, is heated by the electric heater 6 which is a heat source of the air heater 5, and is heated to a predetermined high temperature of about 520 ° C. b is supplied to the thermal decomposition reactor 2.

Further, a temperature detector 7 is provided on the line L ₁ , and a signal V is given to the controller 8 when the high temperature heated air b sent from the air heater 5 is out of a predetermined temperature. The output of the electric heater 6 is adjusted to keep the hot air b at a predetermined temperature. Now,
The dry distillation gas G ₁ produced by dry distillation of the waste a in the thermal decomposition reactor 2 and the thermal decomposition residue c are separated by an exhaust device 9 connected to the outlet side of the thermal decomposition reactor 2. The dry distillation gas G ₁ is supplied to the burner 11 of the melting furnace 10 constituting the combustor via the line L ₃ .

On the other hand, the thermal decomposition residue c is cooled by a cooling device 12 to a temperature at which there is no risk of ignition, for example, to a temperature of about 80 ° C., and then introduced to a separation device 13, where carbon-based combustibility is mainly contained. The component d is separated into a non-combustible component e made of, for example, rubble such as metal, earthenware, or concrete pieces, and the non-combustible component e is collected in the container 14.

The combustible component d separated by the separating device 13 is supplied to the crusher 15, and becomes a combustible component d'of fine powder of 1 mm or less, for example, through the line L ₄ and the melting furnace 10
It is sent to the burner 11 provided in the. The fine powder combustible component d'supplied via the line L ₄ and the dry distillation gas G ₁ supplied via the line L ₃ were sent by the blower 16 via the line L ₅ . Combustion air f
And is burned in the melting furnace 10 in a high temperature range of about 1,300 ° C. Then, the combustion ash generated at this time is melted to form a molten slag g, which flows down into the water tank 17 and is cooled and solidified.

The combustion gas G ₂ generated in the melting furnace 10 is supplied into the waste heat boiler 4 via a line L ₅ to generate steam S at about 400 ° C., and then the dust collector 1
8a, is dust in 18b, most relatively a low temperature clean exhaust gas G ₃ of is released from the chimney 19 into the atmosphere,
A part of it is supplied to the cooling device 12 provided at the subsequent stage of the discharge device 9 via the line L ₆ to cool the thermal decomposition residue C. An induction blower 20 is provided before the chimney 19 and after the dust collector 18b to generate a flow in a predetermined direction in each line.

Although not shown, the waste heat boiler 4 is provided with a power generator driven by a steam turbine as needed, and steam generated by the waste heat boiler 4 is supplied to the steam turbine to generate electricity. You can also do it.
The heat source of the second air heater 5 may be oil-fired instead of the heat transfer heater 6, and a part of the combustion gas G ₂ may be supplied. These are variously selected as needed.

[0015]

As is apparent from the above description, according to the heating method of the thermal decomposition reactor in the waste treatment apparatus of the present invention, the low temperature heated air discharged from the thermal decomposition reactor is heated by the first air. Supplied to the vessel and heated first by steam,
The heated air whose temperature has been raised is supplied to the second air heater to generate a predetermined high temperature heated air, and the high temperature heated air is supplied to the pyrolysis reactor to be heated.

Therefore, the heating source for raising the temperature of the heated air is a fluid that is not corrosive, and even if the combustion gas is used as the heating source of the second air heater, its amount may be small. As a result, there is an effect that the heat transfer area is small and the apparatus can be downsized and the construction cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a system diagram of a waste treatment device for carrying out a method for heating a thermal decomposition reaction in the waste treatment device according to the present invention.

[Explanation of symbols]

1 Waste Supply Device 2 Pyrolysis Reactor 3 First Air Heater 4 Waste Heat Boiler 5 Second Air Heater 6 Heat Transfer Heater 7 Temperature Detector 8 Control Device 9 Discharge Device 10 Melting Furnace 11 Burner 12 Cooling Device 13 Separation device 14 Container 15 Crusher 16 Blower 17 Water tank 18a, 18b Dust collector 19 Chimney 20 Induction blower

Claims (4)

[Claims] 1. A waste product is put into a pyrolysis reactor and heated by heated air to be pyrolyzed to produce a pyrolysis product consisting of a dry distillation gas and a pyrolysis residue, and the dry distillation gas and the pyrolysis product. The residue is separated in an exhaust device, after the thermal decomposition residue is cooled, it is separated into a combustible component and a non-combustible component,
In a waste treatment device configured to supply the dry distillation gas and the combustible component to a combustion furnace for combustion treatment, the combustion gas in the combustor is supplied to a waste heat boiler to generate steam, and the steam is generated. To the first air heater, the low temperature heated air discharged from the pyrolysis reactor is heated by the first air heater, and then heated by the second air heater. A heating method for a thermal decomposition reactor in a waste treatment device, characterized in that the heating air is heated to a high temperature and the heated air is supplied to the thermal decomposition reactor. 2. The second air heater according to claim 1, wherein heating is performed by a heat transfer heater. 3. The second air heater according to claim 1, wherein the second air heater is heated by oil burning. 4. The second air heater according to claim 1, wherein the second air heater is heated by the combustion gas generated by the combustor.