JPH07119951A - Method for reventing white smoke in dust incinerator plant - Google Patents

Abstract

PURPOSE:To prevent white smoke of discharged gas of an incinerator by a method wherein discharged gas of a gas turbine is directly mixed with the discharged gas of the incinerator. CONSTITUTION:Gas turbine discharged gas of a gas turbine 301 passes through a second steam heater 112, a steam reheater 127 and a second water supplying preheater 123, thereafter the gas is fed to a white smoke preventing device 109 installed in the midway part of a smoke passage 102 of an incinerator 100. Gas turbine discharged gas is directly mixed with discharged gas of an incinerator passing through the white smoke preventing device 109. With such an arrangement as above, it is possible to reduce a water vapor inclusion rate of the incinerator discharged gas, discharge it as dried gas into the surrounding atmosphere and then to prevent white smoking of the incinerator discharged gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing white smoke in a refuse incinerator plant for preventing white smoke in exhaust gas discharged from a refuse incinerator such as municipal waste.

[0002]

2. Description of the Related Art Conventionally, incinerator exhaust gas discharged from a refuse incinerator contains a large amount of water vapor, which causes a problem that the incinerator exhaust gas discharged from a chimney to the atmosphere becomes white smoke depending on atmospheric conditions. A white smoke prevention device is installed in the middle of the flue that connects the incinerator and the chimney.

The white smoke prevention device produces high temperature air by an air heater using steam or exhaust gas as a heat source, and mixes this high temperature air with the incinerator exhaust gas, or the incinerator exhaust gas is fed into a separate fuel such as city gas. It is directly heated by combustion.

On the other hand, the exhaust gas discharged from the incinerator is guided to a waste heat boiler to generate steam to recover and use the energy in the exhaust gas. In a plant that uses the steam generated in this waste heat boiler as a driving fluid for a steam turbine that performs power generation, etc., the steam generated in the waste heat boiler is saturated steam, so the generated saturated steam is appropriate for the superheater. It is necessary to superheat to superheated steam of superheat temperature, and the exhaust gas of a separate gas turbine for power generation is used as the heat source of the superheater.

[0005]

However, in the above-mentioned conventional configuration, when a part of the steam generated in the waste heat boiler is used as the heat source of the white smoke prevention device, the steam turbine is provided with the amount of heat. When the amount of heat supplied is reduced and a separate fuel such as city gas is used as the heat source of the white smoke prevention device, there is a problem that the energy consumption of the entire plant increases by the amount of heat.

The present invention solves the above-mentioned problems.
An object of the present invention is to provide a method for preventing white smoke in a refuse incinerator plant that can improve the heat utilization efficiency of the entire plant.

[0007]

In order to solve the above-mentioned problems, the method for preventing white smoke in a refuse incinerator plant of the present invention is a plant that uses waste heat of an incinerator and waste heat of a gas turbine in combination. The gas turbine exhaust gas is supplied to a white smoke prevention device provided in the middle of the flue of the incinerator, and the gas turbine exhaust gas is directly mixed with the incinerator exhaust gas passing through the white smoke prevention device.

[0008]

In the above structure, the gas turbine exhaust gas is a high temperature gas and the amount of water vapor in the gas is small. Moreover, the gas turbine exhaust gas is cleaner than the incinerator exhaust gas, and especially when city gas is used as the fuel, the exhaust gas components become CO _2, H ₂ O, and O ₂ , so even if it is directly discharged to the atmosphere. No problem. Therefore, by directly mixing the gas turbine exhaust gas with the incinerator exhaust gas,
It is possible to reduce the water vapor content in the exhaust gas of the incinerator and discharge it into the atmosphere as a dry gas, so that it is possible to prevent the exhaust gas of the incinerator from becoming white smoke.

Further, conventionally, the heat quantity of the exhaust gas of the incinerator is recovered by the waste heat boiler, the heat quantity is supplied to the white smoke prevention device through the generated steam, and the exhaust gas is further heated through the heat exchanger. For that reason, its thermal efficiency is low, or the energy utilization efficiency of the entire plant was low because it consumed fuel independently in the white smoke prevention device, but in the present invention, the gas turbine exhaust gas directly heats the incinerator exhaust gas and Since it is diluted, the heat efficiency is high and the amount of heat consumed in the white smoke prevention device can be reduced,
Moreover, the amount of heat supplied to the white smoke prevention device uses the waste heat of the energy once consumed in the gas turbine,
The energy utilization efficiency of the entire plant is improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the complex plant includes an incinerator 100 for incinerating municipal waste, a steam turbine power generation device 200 for utilizing waste heat of the incinerator 100, and an independent gas turbine power generation provided separately from the incinerator 100. It is composed of the device 300.

The incinerator 100 is an incinerator outlet gas line 101.
Communicate with the chimney 103 via the flue 102, and in the middle of the flue 102, the first steam superheater 104, the waste heat boiler 105, and the sewage boiler 105 sequentially from the incinerator outlet gas pipe 101 side.
A first feed water preheater 106, a harmful gas removing device 107,
The bag filter 108 and the white smoke prevention device 109 are interposed.

The waste heat boiler 105 recovers energy in the incinerator exhaust gas discharged from the incinerator 100 to generate steam, and supplies steam to supply the steam generated by the boiler to the steam turbine type power generator 200. Pipeline 110
Through to the steam turbine power generation device 200. A first temperature reducer 111, a second steam superheater 112, and a second temperature reducer 113 are provided in this order from the incinerator 100 side in the steam supply pipeline 110.

The steam turbine power generator 200 includes a high pressure steam turbine 201, a low pressure steam turbine 202, and a generator 20.
3 are connected in series, and the high-pressure steam turbine 20
The steam supply line 110 communicates with the air supply port 1 and the condensate line 114 communicates with the exhaust port of the low-pressure steam turbine 202.
Further, a bypass pipe 115 that bypasses the steam turbine power generation device 200 and connects the steam supply pipe 110 and the condensate pipe 114 is provided, and a bypass valve 116 is provided in the bypass pipe 115.

The condensate pipe 114 communicates with the condensate tank 117, and the condensate pipe 114 is provided with a condensate device 118 and a condensate pump 119 in this order from the low pressure turbine 202 side. The condensate tank 117 communicates with the deaerator 121 via the deaerator water supply line 120, and the deaerator water supply line 120 is connected to the deaerator water supply pump 122 and the second water supply from the side of the condensate tank 117. The preheater 123 is interposed.

The deaerator 121 communicates with the waste heat boiler 105 through a water supply pipe 124, and in the middle of the water supply pipe 124, a water supply pump 125 from the deaerator 121 side and a first
The water supply preheater 106 is interposed.

The exhaust port of the high-pressure steam turbine 201 communicates with the supply port of the low-pressure steam turbine 202 through the reheat steam supply line 126, and the steam reheater 127 is provided in the middle of the reheat steam supply line 126. The third temperature reducing device 128 is provided.

In the gas turbine type power generator 300, a gas turbine 301, a compressor 302, and a power generator 303 are connected in series, and the exhaust port of the gas turbine 301 is the exhaust gas pipeline 3.
04 to the white smoke prevention device 109. An auxiliary combustion device 305, a second steam superheater 112, a steam reheater 127, and a second feed water preheater 123 are sequentially provided on the exhaust gas pipe 304 from the gas turbine 301 side. In addition, the second bypass pipeline 12 is branched from the steam supply pipeline 110 between the waste heat boiler 105 and the first steam superheater 104.
9, and the second bypass conduit 129 communicates with the bypass conduit 115 on the downstream side of the bypass valve 116,
A second bypass valve 130 is interposed in the second bypass line 129.

The operation of the above configuration will be described below.
The incinerator exhaust gas of the incinerator 100 is the gas line 10 at the incinerator outlet.
1 through the flue 102 to reach the chimney 103. During this time, the waste heat boiler 105 recovers the waste heat of the incinerator exhaust gas to generate steam, and the steam generated by the boiler is supplied to the steam supply pipe 11
0, the first steam superheater 104 and the second steam superheater 112
To the steam turbine power generation device 200. Further, the first water supply preheater 106 preheats the boiler water supply supplied from the deaerator 121 through the water supply line 124 by the water supply pump 125. Further, the harmful gas removing device 107 removes harmful components in the incinerator exhaust gas, the bag filter 108 removes dust in the incinerator exhaust gas, and the white smoke prevention device 109 raises the temperature of the exhaust gas to generate white smoke. To prevent. This white smoke prevention will be described later.

The first steam superheater 104 uses the incinerator exhaust gas of the incinerator 100 as a heat source to superheat the boiler-generated steam in the steam supply pipeline 110, and turns the saturated steam of the boiler-generated steam into superheated steam having an appropriate superheat temperature. . Furthermore, the first steam superheater 1
The superheated steam that has passed through 04 is superheated in the second steam superheater 112 by using the gas turbine exhaust gas of the gas turbine 301 as a heat source, and the superheated steam having a superheat temperature suitable for increasing the power generated by the high pressure steam turbine 201 and the low pressure steam turbine 202 is generated. obtain. When the exhaust gas temperature of the gas turbine 301 is low, the auxiliary combustion device 305 separately burns the fuel to adjust the exhaust gas temperature to an appropriate value.

Then, the above-mentioned superheated steam is supplied to the steam supply pipe 11
0 to the high-pressure steam turbine 201, and the generated power drives the generator 203. Further, the exhaust gas of the high-pressure steam turbine 201 is guided to the steam reheater 127 through the reheat steam supply pipe 126, and the exhaust gas of the high-pressure steam turbine 201 is reheated in the steam reheater 127 using the gas turbine exhaust gas of the gas turbine 301 as a heat source. Then, the reheated superheated steam is guided to the low-pressure steam turbine 202, and the generated power thereof and the generated power of the high-pressure steam turbine 201 are combined to generate the power from the generator 2.
Drive 03. If necessary, the first temperature reducing device 11
A part of the boiler feed water is sprayed into the superheated steam by the first, second temperature reducer 113 and the third temperature reducer 128 to adjust the temperature of the superheated steam.

Exhaust gas from the low-pressure steam turbine 203 is introduced into a condenser 118 through a condensate pipeline 114, condensed and then introduced into a condensate tank 117 by a condensate pump 119. Also,
Condensed water in the condensate tank 117 is guided to the deaerator 121 through the deaerator water supply line 120 by the deaerator water supply pump 122,
Condensed water is preheated using the gas turbine exhaust gas as a heat source in the second feedwater preheater 123 on the way. The gas turbine exhaust gas passes through the second steam superheater 112, the steam reheater 127, and the second feedwater preheater 123, and then is guided to the white smoke prevention device 109, and directly in the treated incinerator exhaust gas that has passed through the bag filter 108. Aeration is performed to raise the temperature of the treated exhaust gas and prevent the treated exhaust gas from becoming white smoke.

This gas turbine exhaust gas is a high-temperature gas, the amount of water vapor in the gas is small, and the gas turbine exhaust gas is cleaner than the incinerator exhaust gas. Especially, when city gas is used as fuel, the exhaust gas component is CO 2. Since it becomes ₂ and H ₂ O and O ₂ , there is no problem even if it is directly discharged to the atmosphere. Therefore, by directly mixing the gas turbine exhaust gas with the incinerator exhaust gas, it is possible to reduce the water vapor content in the incinerator exhaust gas and discharge it to the atmosphere as a dry gas, turning the incinerator exhaust gas into white smoke. Can be prevented.

Further, in this embodiment, since the incinerator exhaust gas is directly heated by the gas turbine exhaust gas, the thermal efficiency is high and the amount of heat consumed in the white smoke prevention device 109 can be reduced, and the white smoke prevention device 109 is also present. Since the amount of heat supplied to the exhaust gas uses the waste heat of the energy once consumed in the gas turbine 301, the energy use efficiency of the entire plant is improved.

[0024]

As described above, according to the present invention, the gas turbine exhaust gas is directly mixed with the exhaust gas of the incinerator to reduce the water vapor content in the exhaust gas of the incinerator and to be dried in the atmosphere as a dry gas. It is possible to prevent the generation of white smoke in the exhaust gas from the incinerator. Since the incinerator exhaust gas is directly heated by the gas turbine exhaust gas, it is possible to improve the thermal efficiency in the white smoke prevention device and reduce the heat consumption,
Since the waste heat of the energy once consumed in the gas turbine is used, the energy utilization efficiency of the entire plant is improved.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a waste heat utilization complex plant of a refuse incinerator according to an embodiment of the present invention.

[Explanation of symbols]

 100 Incinerator 104 First Steam Superheater 105 Waste Heat Boiler 109 White Smoke Prevention Device 110 Steam Supply Pipeline 112 Second Steam Superheater 200 Steam Turbine Power Generator 201 High Pressure Steam Turbine 202 Low Pressure Steam Turbine 300 Gas Turbine Power Generator 301 Gas turbine 304 exhaust gas pipeline

Claims (1)

[Claims] 1. In a plant that combines the waste heat of an incinerator and the waste heat of a gas turbine, the gas turbine exhaust gas is supplied to a white smoke prevention device provided in the middle of the flue of the incinerator, and a white smoke prevention device is provided. A method for preventing white smoke in a refuse incinerator plant, which comprises directly mixing gas turbine exhaust gas with passing incinerator exhaust gas.