JPH0868523A - Garbage incineration facility - Google Patents

Abstract

(57) [Summary] [Purpose] Efficiently recover waste heat from the exhaust gas of a quasi-continuous waste incinerator that repeats startup and shutdown. [Constitution] Water pipe group in the middle of the exhaust gas pipes 12 and 13 of the refuse incinerator
Boiler 11 with 24 is installed, and a pair of regenerative heating burners 25 and 27 are installed in the boiler 11 to prevent temperature drop during rest.
Installed at the exhaust gas inlet and outlet of the combustion air to burn combustion air
Preheating is performed via the heat storage bodies 33A, 33B attached to 25, 27, and the exhaust gas of one heating burner 25, 27 is heated by the other heating burner.
Introduced into heat storage units 33A and 33B of 25 and 27, both heating burners 25 and 2
A heating burner control device 51 is provided in which 7 is alternately started and stopped at regular intervals. [Effect] The temperature decrease of the boiler during rest can be prevented by the heating burner, and dew point corrosion due to dew condensation can be prevented. Also,
Fuel efficiency can be improved by the heat storage type heating burner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refuse incineration facility which discontinuously operates and stops at an operating rate of about 8 to 16 hours / day.

[0002]

2. Description of the Related Art Conventionally, operation and suspension are repeated discontinuously at an operating rate of about 8 to 16 hours / day (hereinafter referred to as quasi-continuous type).
In the waste incineration facility, dew point corrosion of the boiler tube is severe due to dew condensation of exhaust gas harmful components at rest, so heat recovery from exhaust gas is not performed by the water tube boiler, so exhaust gas is sprayed with cooling water. After being cooled, it is discharged through the dust collector. In addition, a small number of heat exchangers are installed in the flue to reduce the temperature drop and the dew point corrosion is small, and heat is recovered by using a heat exchanger as a heat medium. Some are equipped with a recovery device.

[0003]

However, as described above, cooling with spray water wastes a large amount of effective waste heat, resulting in extremely poor thermal efficiency. Further, in a small heat exchanger using air as a heat medium, sufficient heat recovery is not performed, and there is a problem in that exhaust heat recovery efficiency of exhaust gas is poor.

The present invention can solve the above problems and improve the thermal efficiency by effectively recovering waste heat from exhaust gas even in a quasi-continuous waste incinerator in which operation and suspension are discontinuously repeated. The purpose is to provide a waste incineration facility that can be used.

[0005]

In order to solve the above problems, the present invention provides a boiler provided with a water tube group in the exhaust gas path of a refuse incinerator, and the boiler is installed while the refuse incinerator is at rest. It is provided with a heating burner for heating.

Further, in the above structure, a heat storage type heating burner is arranged at each of the exhaust gas inlet and the exhaust gas outlet of the boiler, and the heating burner has a heat storage body containing a heat storage body in a box communicating with the combustion air port. The exhaust gas pipe and the air supply pipe are connected to these boxes, respectively, and the heating burner is alternately started and stopped at regular intervals, while the other heating burner is burning during the combustion of one heating burner. The heating burner control device for discharging the exhaust gas from the combustion air port via the heat storage body is provided.

In the further construction, a heating burner is arranged on the upstream side of the boiler, and a regenerative air preheating device for preheating the combustion air supplied to the heating burner is provided.
In this air preheating device, an exhaust gas pipe with an exhaust gas control valve interposed is connected to at least one pair of heat storage bodies, and a combustion air supply pipe connected with a heating burner and an air control valve is connected. And a preheating control device for operating the exhaust gas control valve and the air control valve to alternately switch the exhaust gas and the combustion air introduced into the heat storage body at regular intervals.

[0008]

According to the above structure, during operation of the refuse incinerator, waste heat can be recovered from exhaust gas with high efficiency by the boiler using water as a heat medium, and by the heating burner while the refuse incinerator is stopped, The boiler can be heated to prevent dew point corrosion due to dew condensation of harmful substances in the exhaust gas.

Further, since the exhaust gas from the heating burner can be effectively used to heat the combustion air to a temperature close to the inside of the boiler by the heat storage type heating burner or the heat storage type air preheater, the fuel consumption of the heating burner is reduced. The cost can be reduced to almost half, and the operating cost can be significantly reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the refuse incineration facility according to the present invention will be described below with reference to FIG. Stalker type incinerator body 1
Is provided with a dust input hopper 2 on the upstream side, an inclined grate 3 is provided inside, and an ash outlet 4 is formed at the downstream end of the grate 3, and a trash pit 5 is provided to the first intake fan. The combustion air sucked by the first air suction pipe 7 is supplied to the combustion chamber 9 via the steam air preheater 8 or directly from the wind box through the grate 3 to the combustion chamber 9. .

Reference numeral 11 denotes a boiler for recovering waste heat by introducing exhaust gas discharged from the upper part of the combustion chamber 9 through the main exhaust gas introducing pipe 12, and the recovered exhaust gas is transferred from the main exhaust gas discharging pipe 13 to the bag filter 14. After being introduced and dust-removed, it is discharged from the chimney 16 by the main exhaust fan 15.

In the boiler 11, an outer guide cylinder 22 having an upper surface opening and an inner guide cylinder 23 having a lower surface opening are provided in a casing 21.
Are arranged at the same axial center position at a predetermined interval to form detour paths, and the heat exchange water pipe group 24 is arranged on these detour paths. The main exhaust gas introduction pipe 12 is connected to the upper part of the inner guide cylinder 23, and the heat storage type first heating burner 25 that is activated when the incinerator is stopped is installed at the upper end of the inner guide cylinder 23.
Lower guide cylinder 26 vertically provided on the axial center of the casing 21
A main exhaust gas discharge pipe 13 and a heat storage type second heating burner 27 that is activated when the incinerator is stopped are installed in the.

The first and second heating burners 25, 27
Is provided with a heat insulating box 33a that communicates with a mixing chamber 32 in which a fuel injector 31 is arranged at the center through a combustion air port 30, and a heat storage medium 33b is housed in the heat insulating box 33a. Heat storage bodies 33A and 33B are provided respectively. The first and second heat storage bodies 33A and 33B
The heat storage medium 33b housed in is a granular material capable of sending exhaust gas or air through the gap, for example, a ball-shaped one having a diameter of 20 to 50 mm formed by firing alumina, or a crushed alumina electroformed product. An irregular shape having a size of -30 mm is used.

The fuel injectors 31 of the first and second heating burners 25 and 27 are connected to the first and second fuel control valves 41A and 4A.
First and second fuel supply pipes 35A, 35B with 1B interposed
Each is connected. In addition, the first and second heat storage bodies 33
In the heat insulation box 33a of A, 33B, the heat storage medium 33b
The first and second exhaust gas discharge pipes 36A and 36B and the first and second air introduction pipes 37A and
37B are respectively connected.

The first and second air introduction pipes 37A, 37B
Is sucked from the dust pit 5 by the second intake fan 42 through the second air suction pipe 43 and branched, and
First and second air control valves 44A and 44B are respectively interposed. In addition, the first and second exhaust gas discharge pipes 36A, 36
B is the main exhaust gas exhaust pipe 1 through the first and second exhaust gas control valves 45A and 45B and the first and second exhaust fans 46A and 46B.
Connected to 3. Further, a main exhaust gas introduction control valve 47 is interposed in the main exhaust gas introduction pipe 12, and a main exhaust gas discharge control valve 48 is interposed in the main exhaust gas discharge pipe 13.

Therefore, when the refuse incinerator is at rest, the heating burner controller 51 controls the main exhaust gas introduction control valve 47.
The main exhaust gas emission control valve 48 is closed, the second air supply fan 42 and the second exhaust fan 46B are activated, and
The fuel control valve 41A is opened, the first air control valve 44A is opened, the first exhaust gas control valve 45A is closed, and the second fuel control valve 41B.
Is closed, the second air control valves 44A and 44B are closed, and the second exhaust gas control valve 45B is opened, thereby activating the first heating burner 25 and heating the first heat storage body 33A to a temperature close to the boiler internal temperature. The combustion air burns the fuel to prevent the temperature of the boiler 11 from lowering, and introduces the exhaust gas into the second heat storage body 33B to insulate the heat insulation box 33a.
And the heat storage medium 33b can be heated.

Further, after the startup time set by the capacities of the first and second heat storage bodies 33A and 33B and the type of the heat storage medium 33b, the heating burner control device 51 closes the first fuel control valve 41A and the first fuel control valve 41A. The air control valve 44A is closed, the first exhaust gas control valve 45A is opened, the second fuel control valve 41B is opened,
By opening the second air control valves 44A and 44B and closing the second exhaust gas control valve 45B, the first heating burner 25 is stopped and at the same time the second heating burner 27 is activated, and the second heat storage body 33B is used in the boiler. It is possible to burn the fuel with the combustion air heated to near the temperature to prevent the temperature of the boiler 11 from lowering, and to introduce the exhaust gas into the second heat storage body 33B to heat the heat insulation box 33a and the heat storage medium 33b.

Therefore, according to the first embodiment described above, in the quasi-continuous type refuse incinerator which repeats stop and operation, the heating burner controller 51 controls the first heating burner 25 and the second heating when the refuse incinerator is stopped. The burner 27 and the burner 27 are alternately started and stopped at each start time, and the fuel is burned by using the combustion air preheated by the first heat storage body 33A or the second heat storage body 33B heated by the discharged exhaust gas to burn the fuel. 11 can be heated to prevent dew condensation in the boiler 11 to prevent dew point corrosion, and at the same time, the exhaust gas can be used to heat the heat storage body 33B or 33A of the heating burner 27 or 25 on the stop side. As a result, the first and second heating burners 2 to be activated at rest
The fuel consumption of 5,27 can be reduced to about half and the operating cost can be significantly reduced, and the waste heat can be effectively recovered by the boiler 11 using water as a heat medium when operating the refuse incinerator. The hot water or steam obtained from the boiler 11 can be used as a heat supply source even during a stop.

Next, a second embodiment of the refuse incineration facility according to the present invention will be described with reference to FIG. The same members as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. This second
In the example, in the quasi-continuous waste incinerator that repeats suspension and operation, in the exhaust gas path in the furnace body 61 of the waste incinerator,
A boiler 62 having a water pipe group for waste heat recovery is arranged, and a heating burner 63 that is activated when the refuse incinerator is stopped is installed in the furnace main body 61 on the upstream side of the boiler 62.
A regenerative air preheating device 64 is provided in the combustion air supply path to the heating burner 63.

That is, the boiler 62 is installed in the exhaust gas passage in the furnace body 61, and the exhaust gas discharged from the boiler is introduced into the bag filter 14 from the exhaust gas pipe 65 to remove dust, and then the main exhaust fan 15 By the chimney 1
6 is discharged into the atmosphere. A heating burner 63 is installed on the upper rear wall of the ash outlet 4 of the furnace body 61 to heat the boiler 62 when the refuse incinerator is stopped.

The heat storage type air preheater 64 is heated by the exhaust gas discharged from the heating burner 63, and is connected to the pair of first heat storage body 71A and second heat storage body 71B and the boiler 62 to the bag filter 14. From the upstream side of the exhaust gas pipe 65, the first and second exhaust gas control valves 72A, 72
B, first and second exhaust gas introduction fans 73A and 73B, and first and second exhaust gas introduction pipes 74A and 74B connected to the first and second heat storage bodies 71A and 71B, and the first and second heat storage bodies. 71A, 71B to the third and fourth exhaust gas control valves 72
First and second exhaust gas discharge pipes 75A and 75B connected to the downstream side of the exhaust gas pipe 65 via C and 72D, and the first and second exhaust air suction pipes 43 from the discharge side of the second intake fan 42.
The first and second heat storage bodies 7 are provided via the air control valves 76A and 76B.
1st, 2nd air introduction pipe 77 connected to 1A, 71B
A, 77B and first and second air inlet pipes 78A, 78 connected to the heating burner 63 from the first and second heat storage bodies 71A, 71B through the third and fourth air control valves 76C, 76D.
B and are provided. A fuel supply pipe 80 having a fuel control valve 79 interposed therein is connected to the heating burner 63.

The first and second heat storage bodies 71A and 71B are
A large number of granular heat storage media are filled in the heat insulation box, and exhaust gas and combustion air are alternately flowed through the gaps between the heat storage media. The heat storage media is, for example, a ball shape having a diameter of 20 to 50 mm obtained by firing alumina. Used in the above, or crushed stone electroformed products of 20-30 mm indefinite shape are used. Depending on the capacity of the heat insulation box and the type of heat storage medium,
Exhaust gas and combustion air are switched alternately in about 20 seconds to 3 minutes.

Therefore, when the refuse incinerator is stopped,
The preheat control device 81 activates the second intake fan 42 and the first exhaust gas introduction fan 73A, opens the first exhaust gas control valve 72A, closes the second exhaust gas control valve 72B, and opens the third exhaust gas control valve 72C. , The fourth exhaust gas control valve 72D is closed, the first air control valve 76A is closed, and the second air control valve 7 is closed.
6B is opened, the third air control valve 76C is closed, the fourth air control valve 76D is opened, the fuel control valve 79 is opened, and the fuel gas is supplied to the heating burner 63.
3 can burn the combustion air and the fuel preheated by the second heat storage body 71B, and the exhaust gas of the heating burner 63 can be introduced into the first heat storage body 71A to heat the heat storage medium.

Further, after the start-up time set by the capacities of the first and second heat storage bodies 71A and 71B and the type of heat storage medium, the preheat control device 81 causes the first exhaust gas introduction fan 7 to operate.
3A is stopped, the second exhaust gas introduction fan 73B is started, the first exhaust gas control valve 72A is closed, the second exhaust gas control valve 72B is opened, the third exhaust gas control valve 72C is closed, and the fourth exhaust gas control valve 72D is opened. Open, first air control valve 76A is open, second air control valve 76B is closed, third air control valve 76C
Is opened and the fourth air control valve 76D is closed, the fuel is burned by the combustion air preheated by the second heat storage body 71B in the heating burner 63, and the exhaust gas of the heating burner 63 is discharged to the second heat storage body 71B. It can be introduced to heat the heat storage medium. The heating burner 63 can prevent the temperature of the boiler 62 from decreasing and prevent the dew point corrosion of the water pipe due to the condensation of harmful substances. Steam and hot water obtained from the boiler 62 while the refuse incinerator is at rest can be used as a heat supply source.

According to the second embodiment described above, the heating burner 6 is operated when the quasi-continuous type refuse incinerator, which is repeatedly stopped and operated, is stopped.
By starting No. 3, it is possible to prevent the temperature of the boiler 62 from decreasing and prevent dew point corrosion of the water pipe due to dew condensation of harmful substances, and the preheating control device 81 allows the first and second heat storage bodies 71A, 71B to Exhaust gas introduction and combustion air introduction are repeated alternately at regular start times, and the heating burner 6
The combustion air supplied to the No. 3 is preheated to a high temperature close to the temperature inside the furnace by the first heat storage body 71A or the second heat storage body 71B heated by the exhaust gas, so that the heating burner 6
It is possible to reduce the fuel consumption of No. 3 to about 1/2 that in the case of not preheating. Therefore, during the operation of the refuse incinerator, the waste heat can be recovered with high efficiency by the boiler 62 using water as a heat medium, and the heating burner 63 can be started with a low fuel consumption during the rest to significantly reduce the operating cost. At the same time, it is possible to prevent dew point corrosion of the boiler 62, and the steam and hot water obtained from the boiler 62 during rest can be used as a heat supply source.

[0026]

As described above, according to the present invention, during operation of the refuse incinerator, waste heat can be recovered from the exhaust gas with high efficiency by the boiler using water as a heat medium. During the rest, the heating burner can heat the boiler to prevent dew point corrosion due to dew condensation of harmful substances in the exhaust gas.

In addition, since the exhaust gas from the heating burner can be effectively used to heat the combustion air to a temperature close to the boiler internal temperature by the heat storage type heating burner or the heat storage type air preheater, the fuel consumption of the heating burner is reduced. The cost can be reduced to almost half, and the operating cost can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a refuse incineration facility according to the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of the refuse incineration facility according to the present invention.

[Explanation of symbols]

 1 Furnace Main Body 9 Combustion Chamber 11 Boiler 12 Main Exhaust Gas Pipe 13 Main Exhaust Gas Exhaust Pipe 24 Water Tube Group 25 First Heating Burner 27 Second Heating Burner 30 Combustion Air Port 33A First Heat Storage Body 33B Second Heat Storage Body 33a Insulation Box 33b Heat Storage Medium 35A, 35B 1st, 2nd fuel supply pipe 36A, 36B 1st, 2nd exhaust gas discharge pipe 37A, 37B 1st, 2nd air introduction pipe 41A, 41B 1st, 2nd fuel control valve 44A, 44B 1st, 1st Second air control valve 45A, 45B First and second exhaust gas control valve 47 Main exhaust gas introduction control valve 48 Main exhaust gas discharge control valve 51 Heating burner control device 61 Reactor body 62 Boiler 63 Heating burner 64 Air preheating device 65 Exhaust gas pipe 71A, 71B 1st, 2nd heat storage body 72A-72D 1st-4th exhaust gas control valve 74A, 74B 1st, 2nd exhaust gas Introduction pipe 75A, 75B First and second exhaust gas discharge pipes 76A to 76D First to fourth air control valves 77A, 77B First and second air introduction pipes 78A, 78B First and second air feed pipes 79 Fuel control Valve 80 Fuel supply pipe 81 Preheat control device

Claims (3)

[Claims] 1. A refuse incinerator characterized by arranging a boiler having a water tube group in an exhaust gas path of the refuse incinerator, and providing a heating burner for heating the boiler while the refuse incinerator is stopped. . 2. A heat storage type heating burner is provided at each of an exhaust gas inlet and an exhaust gas outlet of a boiler, and the heating burner is provided with a heat storage body containing a heat storage body in a box communicating with a combustion air port. An exhaust gas pipe and an air supply pipe are connected to these boxes, respectively, and the heating burner is alternately started and stopped at regular intervals, while the combustion air port of the other heating burner is burning during the combustion of one heating burner. The waste incineration facility according to claim 1, further comprising a heating burner control device that discharges exhaust gas from the heat storage body through the heat storage body. 3. A heating burner is arranged on the upstream side of the boiler, and a regenerative air preheating device for preheating the combustion air supplied to the heating burner is provided. This air preheating device has at least one pair of regenerators. The exhaust gas control valve and the exhaust gas control valve are connected to each other, and the combustion air supply pipes connected to the heating burner and the air control valve are connected to each other. 2. The waste incineration facility according to claim 1, further comprising a preheating control device that operates a control valve to alternately switch the exhaust gas and the combustion air introduced into the heat storage body at regular intervals.