JP2001173927A - Waste incinerating system and method of heating bag filters therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste incinerating system and a method of heating bag filters disposed within the system, wherein a bag filter in a rest phase can be heated by an associated electric heater with relatively decreased electric power consumption. SOLUTION: The incinerating system comprises a plurality of elemental incinerator systems with respective air heaters, wherein the respective elemental incinerator systems have the air heaters 13a, 13b respectively to which air heating ducts 21a, 21b are connected with branch ducts 22a, 22b. These branch ducts 22a, 22b are connected to the bag filters 16a, 16b respectively, so that hot air heated by either of the air heaters 13a, 13b corresponding to one of the incinerator systems staying in operation phase is supplied to either of the bag filters 16a, 16b of one of the incinerator systems staying in rest phase so as to heat the bag filter staying in rest phase.

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 in which a plurality of incineration facilities having an air heater are arranged, and a method for heating a bag filter in the refuse incineration facility.

[0002]

2. Description of the Related Art In a refuse incineration plant, after the incineration exhaust gas is cooled in several stages, exhaust gas treatment for removing dust collection and harmful substances is performed. One of the above-mentioned exhaust gas cooling stages is air heating. Vessels may be installed. This air heater is a device for heating combustion air and the like, and is used in a refuse incinerator having a gas cooler provided with a gas cooler for cooling refuse incineration exhaust gas by water spray, a so-called gas cooler type incinerator. Often used. Exhaust gas cooling and exhaust gas treatment in such a waste incineration plant are performed, for example, as follows.

[0003] The incineration exhaust gas discharged from the combustion chamber of the incinerator is sprayed with water when flowing into a gas cooler, cooled, and then introduced into an air heater. Here, the incineration exhaust gas is cooled again by heat exchange with air. Next, slaked lime powder is blown into the cooled incineration exhaust gas, and a treatment for removing an acidic gas such as hydrogen chloride is performed. Thereafter, the incineration exhaust gas is introduced into a dust collector (bag filter), is subjected to dust collection processing, is further denitrated, and is released to the atmosphere. The air introduced into the air heater is heated and supplied to applications such as combustion, use of residual heat, and prevention of white smoke.

[0004] By the way, as described above, in the refuse incineration plant, a treatment for removing hydrogen chloride by blowing slaked lime is performed. Therefore, slaked lime is blown into the bag filter in addition to the dust scattered from the incinerator. The deliquescent calcium chloride which is a reaction product at this time is collected. If the refuse incineration facility is suspended and left as it is, the calcium chloride trapped in the bag filter absorbs moisture in the air and dissolves, causing significant corrosion of the equipment. Or clog the filter cloth.

For this reason, as disclosed in Japanese Patent Application Laid-Open No. 8-266834, a heating device is provided in a bag filter of a refuse incineration plant. When the refuse incineration facility is inactive, it is heated by the electric heater of the heating device, and the temperature in the bag filter is maintained at the same level as the temperature of the incineration exhaust gas flowing while the incinerator of the incineration facility is operating. To prevent moisture absorption.

[0006]

In the above-mentioned prior art, the heated air discharged from the air heater is supplied to an incinerator as combustion air, supplied to an application for use of residual heat, white smoke of exhaust gas, or the like. It is supplied as a heating heat source for preventing gasification, but there is surplus depending on operating conditions. For this reason, in a refuse incineration facility in which a plurality of series of incineration facilities are arranged, during operation, a surplus of heated air obtained from the air heater is released to the atmosphere, and once recovered heat is discarded. . On the other hand, in the incineration facility during suspension, the bag filter is heated by the electric heater as described above. As a result, much electric power is consumed, and the running cost of the incinerator becomes large.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a refuse incinerator and a method for heating the bag filter, which can reduce the load power of the electric heater when heating the inactive bag filter.

[0008]

The above object is achieved by the following invention. The first invention is a refuse incineration plant in which a plurality of incineration facilities equipped with air heaters are arranged, and a branch duct branched from a heated air duct connected to an air heater of each incinerator series incineration facility And the branch ducts are connected to bag filters of other incinerator series incinerators, respectively.

According to the present invention, a heated air duct connected to an air heater belonging to a certain incinerator series is connected to a bag filter belonging to another incinerator series by a branch duct. As a result, heated air can be supplied from the air heater of the operating incinerator system to the inactive incinerator system bag filter. As a result, it becomes possible to heat the bag filter of the inactive incinerator system with the heated air generated in the operating incinerator system.

A second invention relates to a method for heating a bag filter in a refuse incineration system in which a plurality of incineration facilities having an air heater are arranged, wherein the air filter is heated by an air heater of an operating incinerator series incineration facility. A method of heating a bag filter, characterized in that air that has been blown is blown to a bag filter of an incinerator system of an incinerator system that is inactive to heat the bag filter that is inactive.

According to the present invention, the heating air generated in the incinerator of the incinerator system in operation is blown to the bag filter of the incinerator of the incinerator system in operation. From a series of incinerators. As a result, it is possible to reduce the amount of a heat source for heating the dormant bag filter.

[0012]

FIG. 1 is a diagram showing an example of an embodiment of a refuse incinerator according to the present invention. This figure is
An incinerator having an incinerator provided with an air heater shows a configuration of a waste incinerator in which a plurality of incinerators are arranged. For the sake of simplicity, a case is shown in which the incinerators are of two systems, and each incinerator is of the No. 1 furnace system and the No. 2 furnace system.

The reactor No. 1 consisting of the reactor No. 1 and the reactor No. 2
In the series of incinerators, 10a and 10b are incinerators, 1
2a and 12b are gas coolers, 13a and 13b are air heaters for obtaining multipurpose heated air, 14a and 14b are combustion air heaters, 16a and 16b are bag filters,
7a and 17b are denitration devices. 20a and 20b are blowers for air heaters, 23a and 23b are air blowers for combustion, and 24a and 24b are feeders for slaked lime powder. 30 indicates municipal waste.

Since the first and second furnaces in the incinerator have the same configuration, the following description of the first furnace is applicable to the second furnace.

In the above incinerator, the air heater 1
Heating air duct 21a connected to the heating air outlet 3a
However, it is divided into three according to applications. Of these three branch ducts, two are ducts that supply heated air for utilization of residual heat and ducts that are used to prevent white smoke from incineration exhaust gas. Branch duct 22a is provided.

The heated air branch duct 22a is connected to the flue 15b of the incineration exhaust gas on the inlet side of the bag filter 16b of the No. 2 furnace system. A heating air branch duct 22b branched from the heating air duct 21b of the No. 2 furnace system
Is connected to the flue 15a of the incineration exhaust gas on the inlet side of the bag filter 16a of the first reactor.

A damper 25 is provided in the flue 15a of the incineration exhaust gas.
a, and a damper 27a is also provided in the heated air duct 22b connected to the flue 15a of the incineration exhaust gas from the No. 2 furnace system. These dampers 25
The gas flowing into the bag filter 16a can be switched to either the incineration exhaust gas or the heated air by means of a and 27a. Similarly, a damper 25b is provided in the flue 15b of the incineration exhaust gas of the No. 2 furnace system,
The heating air duct 22a connected from the No. 1 furnace line also
A damper 27b is provided so that the gas flowing into the bag filter 16b can be switched.

The operation of the refuse incineration facility according to the above configuration is as follows.
It is performed as follows. When the incineration exhaust gas discharged from the combustion chamber 11a of the incinerator flows into the gas cooler 12a,
Water is sprayed and cooled to about 300 ° C. to 450 ° C., and then introduced into the air heater 13a. Air heater 13
In a, air is supplied from the air heater blower 20a, and the incineration exhaust gas uses the air as a cooling medium and has a temperature of 300 ° C.
Cool to 370 ° C. The air supplied as a cooling medium is heated to about 200 ° C. to 250 ° C. and discharged. Thereafter, the incineration exhaust gas is sent to the combustion air heater 14a. In the combustion air heater 14a, the incineration exhaust gas is cooled by air supplied from the combustion air blower 23a. The cooled incineration exhaust gas is supplied to the bag filter 16a.
After the acidic gas such as hydrogen chloride is removed by contact with slaked lime powder blown from the slaked lime powder feeder 24a in the flue upstream of the ash powder, the powder is sent to the bag filter 16a. The incineration exhaust gas that has been subjected to dust collection by the bag filter 16a is:
Nitrogen oxides are removed by the denitration device 17a, and are released to the atmosphere from the chimney 18.

In the refuse incineration plant operated in this manner, when one of the systems, for example, the No. 2 furnace system is shut down, the following measures are taken in order to avoid the temperature decrease of the bag filter 16b of the No. 2 furnace system. do. The damper 25b provided in the flue 15b of the incineration exhaust gas of the No. 2 furnace series is closed, and the damper 26a and the damper 27b provided in the heating air duct 22b connected from the No. 1 furnace series to the No. 2 furnace series are removed. Open. By these damper operations, heated air of 200 ° C. to 250 ° C. flows into the bag filter 16b at rest, and the inside of the bag filter 16b is kept in a state where salts such as calcium chloride do not absorb moisture.

Although FIG. 1 shows a refuse incinerator in which two lines of incinerators are arranged, the present invention is not limited to two lines of incinerators.

[0021]

According to the present invention, the heating air branch ducts branched from the heating air ducts connected to the air heaters of the respective incineration facilities are connected to the bag filters of the other incineration facilities, respectively. The air heated by the air heater of the operating incinerator can be sent to the bag filter of the inactive incinerator to heat the inactive bag filter. Thus, the load on the electric heater for heating the dormant bag filter is reduced, so that power is saved and the operating cost is reduced.

[Brief description of the drawings]

FIG. 1 is a view showing an example of an embodiment according to a refuse incineration plant of the present invention.

[Explanation of symbols]

10a, 10b Incinerators 11a, 11b Combustion chambers 12a, 12b Gas coolers 13a, 13b Air heaters 14a, 14b Combustion air heaters 15a, 15b Flue gas for incineration exhaust gas at the bag filter inlet side 16a, 16b Bag filter 18 Chimney 21a , 21b Heated air duct 22a, 22b Heated air branch duct 25a, 25b Damper 26a, 26b Damper 27a, 27b Damper 30 Municipal waste

Claims (2)

[Claims] In a refuse incineration plant in which a plurality of incineration facilities equipped with air heaters are arranged, a branch duct branched from a heated air duct connected to an air heater of each incinerator series incineration facility is provided. A refuse incineration plant, wherein said branch ducts are connected to bag filters of other incinerator series incineration plants. 2. A method for heating a bag filter in a refuse incineration plant in which a plurality of incinerators having air heaters are arranged in a series, wherein the air heated by the air heater of the operating incinerator series incinerator is stopped. A method of heating a bag filter, comprising blowing air to a bag filter of an incinerator system of incinerators in the middle to heat a bag filter that is inactive.