JPH1089653A - Temperature controlling method for combustion melting furnace and waste treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply, easily and stably control a temperature when a temperature in a combustion melting furnace becomes high due to change of quality or amount of waste or other cause by lowering the temperature in the furnace by supplying excess combustion air at the time of exceeding a predetermined value at the temperature in the furnace. SOLUTION: Waste (a) heated by heated air (g) is thermally decomposed to become thermal decomposition gas G and decomposed residue (b) containing nonvolatile components, and separated by an exhaust unit 6. The gas G is supplied to a burner 14 of a combustion melting furnace 13. When the temperature of the furnace 13 becomes high exceeding a predetermined value, it is sensed by a temperature sensor in the furnace, and combustion air (e) burnt, for example at an air ratio of 1.3 is supplied excessively exceeding this air amount. To increase the supply amount of the air (e), a volume of a forced draft fan 18 is previously set to high, and the air is blown from blowing ports 19a to 19d by considering a rising ratio of the temperature in the furnace and a temperature distribution in the furnace and considering a balance between the blowing amount and blowing positions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to industrial waste such as waste (general waste such as municipal waste from homes and offices, waste plastic, car shredder dust, waste office equipment, electronic equipment, and chemical products). Method for operating a combustion-melting furnace in waste treatment in which a pyrolysis gas generated by the pyrolysis of a substance (including a combustible material) and a combustible component in a pyrolysis residue also generated by the pyrolysis are supplied and burned And a waste disposal apparatus using the method for operating a combustion melting furnace.

[0002]

2. Description of the Related Art Conventionally, a pyrolysis gas and a pyrolysis residue are generated by pyrolysis of waste, and a flammable component and a non-flammable component are separated from the pyrolysis residue. The combustion and melting furnace for supplying the pyrolysis gas pushes the combustible component and the pyrolysis gas together with the combustion air and burns, and melts the generated ash to form slag (Japanese Patent Publication No. Hei 6-1994). No. 56253).

[0003]

However, in the above-mentioned combustion melting furnace, fluctuations in the amount of heat generated due to the type of waste, for example, garbage, plastics, paper, etc., due to the water content and components, or fluctuations in the amount of waste supplied. Or, due to other factors, the properties and amounts of pyrolysis gas and combustible components generated by pyrolysis of waste fluctuate, and the temperature in the furnace of the combustion melting furnace that supplies these pyrolysis gases and combustible components May rise above a predetermined temperature.

In such a case, about 2 downstream of the combustion melting furnace is required.
The exhaust gas at 00 ° C. is returned to the combustion melting furnace to control the temperature in the furnace by lowering it. However, in the method of controlling the furnace temperature by the exhaust gas, a device for returning the exhaust gas is required, and the device itself may be complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for controlling the temperature of a combustion melting furnace in the treatment of waste, which is simple and easy to stabilize when the temperature inside the furnace increases due to fluctuations in the quality and quantity of waste and other factors. An object of the present invention is to provide a controllable temperature control method for a combustion melting furnace and a waste disposal apparatus using the method.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is to thermally decompose a waste that has been introduced, to generate a pyrolysis gas and a pyrolysis residue mainly composed of nonvolatile components, After separating the decomposition residue into a combustible component and a non-combustible component, the pyrolysis gas and the combustible component are burned together with combustion air by a combustion melting furnace, and the resulting ash is melted. In the method for controlling the temperature of a combustion melting furnace in a waste treatment for cooling and discharging the combustion exhaust gas generated during melting, when the temperature in the furnace of the combustion melting furnace rises above a predetermined value, the combustion air is cooled. That is, the temperature in the furnace of the combustion melting furnace is reduced by supplying the excess.

[0007] When the temperature in the furnace of the combustion and melting furnace rises above a predetermined value due to fluctuations in the quality or quantity of waste and other factors, the combustion and melting furnace is supplied by excessively supplying low-temperature combustion air. Furnace temperature can be reliably and stably reduced.

[0008] Further, a pyrolysis reactor which heats the introduced waste with heated air to pyrolyze it into a pyrolysis gas and a pyrolysis residue mainly composed of non-volatile components, and a pyrolysis reactor produced by the pyrolysis reactor. A discharge device for separating and discharging a pyrolysis gas and a pyrolysis residue, a separation device for separating the pyrolysis residue discharged from the discharge device into a combustible component and a non-combustible component, A combustion-melting furnace that burns the toxic component and the pyrolysis gas together with the combustion air and melts the generated ash.
In a waste treatment apparatus having a gas cooling device for cooling combustion exhaust gas generated in the combustion melting furnace, the temperature of the combustion melting furnace is controlled by the temperature control method of the combustion melting furnace.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method for controlling the temperature of a combustion melting furnace in a waste treatment and a waste treatment apparatus using the same according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a system diagram showing an embodiment of a waste disposal apparatus according to the present invention. The waste disposal apparatus 1 of the present embodiment crushes waste a such as municipal waste into a 150 mm square or less with a crusher such as a biaxial shearing type, and throws the crushed waste into the loading section 2 by a conveyor or the like. It is supplied to the thermal decomposition reactor 5 via the feeder 3. Waste a fed to the pyrolytic reactor 5 is heated by the heat exchanger (not shown) disposed on the downstream side of the combustion melting furnace 13, heated air is introduced by the heated air lines L ₁ g ( The heating medium is used to heat to 300 to 600 ° C, usually to about 450 ° C.

Further, the waste a heated by the heated air g is thermally decomposed into a pyrolysis gas G ₁ and a pyrolysis residue b mainly composed of a non-volatile component. Separated. The pyrolysis gas G ₁ separated by the discharge device 6 is supplied from above the discharge device 6 to the burner 14 of the combustion melting furnace 13 via the pyrolysis gas line L ₂ .

Further, since the pyrolysis residue b discharged from the discharge device 6 has a relatively high temperature of approximately 450 ° C., it is cooled to approximately 80 ° C. by the cooling device 8 and is, for example, a magnetic separation type, an eddy current type, or a centrifugal type. Is supplied to a known single or combined separation device 9 such as an incineration type or a wind separation type, and is separated into a combustible component c and a non-combustible component d.
Collected to 0 and reused. The combustible component c is supplied to the pulverizer 1
The 1, for example, 1mm milled below, supplied to the combustion melting furnace 13 through the combustible component line L _3.

On the other hand, a part of the combustion air e supplied by the forced air blower 18 is blown from the burner 14 of the combustion melting furnace, and an arrow 19 provided near the burner 14.
a, and is burned in the combustion melting furnace 13 at a high temperature of about 1,300 ° C. together with the pyrolysis gas G ₁ supplied from the pyrolysis gas line L ₂ and the combustible component c. Is done. Further, the combustion air e is indicated by arrow 1 at the top of the furnace.
Air is blown from each of the blowout port shown by 9b, the blowout port shown by arrow 19c as secondary air, and the blowout port shown by arrow 19d as tertiary air.

The ash generated as a result of the combustion of the combustible component c becomes molten slag f and adheres to the inner wall of the combustion melting furnace 13,
Furthermore, it flows down the inner wall, falls from the bottom outlet 15 into the water tank 16, and is cooled and solidified.

Next, the flue gas G ₂ generated in the combustion melting furnace 13 passes through a high-temperature air heater 17 and is passed through a flue gas line L ₅ through a gas cooling device, for example, water to spray the flue gas G ₂ . is cooled in a gas cooling tower 20 for cooling, is dust in the dust collector 21 through the flue gas line L _6, after removing the harmful components further exhaust converter 22, a low-temperature clean gas G ₃ of Chimney 24 via the draft fan 23
Emitted from the atmosphere. Some of the clean exhaust gas G ₃ are returned to the cooling unit 8 by the exhaust gas circulation line L ₇ via a fan 25.

In the waste treatment apparatus 1 having the above-described configuration, as described above, the combustion and melting furnace 13 includes the type of the waste a, for example, garbage, plastic, paper, etc. fluctuations or other factors change or supplying waste of calorific value by waste a and fluctuates properties and yield of the pyrolysis gases G ₁ and combustible components c produced by thermal decomposition, these In some cases, the temperature in the furnace 13 of the supplied combustion melting furnace 13 becomes higher than a predetermined value, for example, 1300 ° C.

In the method for controlling the temperature of the combustion and melting furnace according to the present embodiment, when the furnace temperature of the combustion and melting furnace 13 exceeds a predetermined value as described above, it is detected by a furnace temperature sensor. Usually, for example, combustion air e burned at an air ratio of 1.3 is supplied in excess of this air amount.
In order to increase the supply amount of the combustion air e, as shown in FIG. 1, the capacity of the push-in blower 18 is set high in advance to prepare for an excessive supply of the combustion air e. The excess air supply amount of the combustion air e is blown from the inlets 19a to 19d in consideration of the rate of increase in the furnace temperature, the furnace temperature distribution, and other conditions, and the balance of the blown amount and the location of the blow.

Combustion air e blown into the combustion melting furnace 13
Since air at room temperature is used, the temperature is low, and the furnace temperature can be cooled with a smaller amount of air than in the case where conventional exhaust gas is blown. In addition, the exhaust gas circulation device conventionally used can be omitted, and the equipment is simple and economical.

[0019]

According to the method for controlling the temperature of a combustion melting furnace in the waste treatment of the present invention, when the temperature inside the furnace is increased due to fluctuations in the quality and quantity of waste and other factors, it is simple and easy to stabilize. To lower the furnace temperature.

[Brief description of the drawings]

FIG. 1 is a system diagram showing one embodiment of a waste disposal apparatus according to the present invention.

[Explanation of symbols]

1 waste disposal device 5 the pyrolysis reactor 6 discharge device 9 separator 13 combustion melting furnace 20 the gas cooling tower (gas cooler) G ₁ pyrolysis gas G ₂ combustion exhaust a waste b pyrolysis residue c combustible components d Non-combustible component e Combustion air g Heated air (heat medium)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F23G 5/027 ZAB F23G 5/027 ZABZ 5/16 ZAB 5/16 ZABE F23J 15/06 ZAB F23J 15/00 ZABK

Claims (2)

[Claims] Claims: 1. A thermal decomposition of an input waste to generate a pyrolysis gas and a pyrolysis residue mainly composed of a non-volatile component, and convert the pyrolysis residue into a combustible component and a non-combustible component. After separation, the pyrolysis gas and the combustible component are burned together with combustion air by a combustion melting furnace to melt the generated ash, and to cool and discharge the flue gas generated during the combustion and melting. In the method for controlling the temperature of the combustion melting furnace in the material treatment, when the furnace temperature of the combustion melting furnace rises above a predetermined value, the combustion air is excessively supplied to increase the furnace temperature of the combustion melting furnace. A method for controlling the temperature of a combustion melting furnace, characterized by lowering the temperature. 2. A pyrolysis reactor which heats the introduced waste with heated air and pyrolyzes into a pyrolysis gas and a pyrolysis residue mainly composed of non-volatile components, and a pyrolysis reactor produced by the pyrolysis reactor. An exhaust device for separating and discharging a pyrolysis gas and a pyrolysis residue, a separation device for separating the pyrolysis residue discharged from the exhaust device into a combustible component and a non-combustible component, And a pyrolysis gas, which burns the pyrolytic gas together with the combustion air, and melts the generated ash, and a gas cooling device that cools the combustion exhaust gas generated in the combustion melting furnace. A waste treatment apparatus, wherein the temperature of the combustion melting furnace is controlled by the temperature control method of the combustion melting furnace according to claim 1.