JPH0229501A - Complex plant - Google Patents

Abstract

PURPOSE:To make an effective utilization of discharged gas of a gas turbine and reduce an occurrence of NOx by a method wherein the discharged gas of the turbine is passed through a heat exchanger to increase a temperature of a discharged gas of a boiler, its high temperature discharged gas is supplied to a crusher, fine powder coals are transferred to a storing bin, the fine powder coal within the storing bin is transported by the low temperature turbine discharged gas passed through the heat excharger to the boiler so as to perform its combustion. CONSTITUTION:A part 110 of a gas turbine discharged gas 100 is passed through a heat excharger 50, a temperature of a discharged gas 501 from a fine powder coal boiler is increased, a return flow rate of gas is adjusted in such a way as a gas temperature at an inlet of a desulfurization device becomes a predetermined value and then the gas is merged with a discharged gas 120 of the gas turbine. As its remaining volume, fine powder coal supplied from a storing bin 65 by a feeder 67 is transported to a burner as a fine cool conveying line 112. The discharged gas of which temperature is increased by the heat exchanger 50 is sent as a drying line 510 to the mill crusher 60 and a storing line 511. An enthalpy provided by the drying line 510 is mainly used in a coal drying and a temperature of the storing line 511 is decreased. Accordingly, heat loss for the surrounding atmosphere is restricted to a minimum value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composite plant of a gas turbine combustion device, and particularly to a composite plant that can effectively utilize exhaust gas from a gas turbine.

[Prior art and problems to be solved by the invention] Gas turbines have high power generation efficiency and are extremely clean power generation devices because the fuel is gas such as natural gas. However, the oxygen concentration in the exhaust gas from gas turbines is high (generally 15 to 16%), and the exhaust gas temperature is also relatively high (usually around 600°C), so releasing it directly into the atmosphere is energy-consuming. This is a loss.

An object of the present invention is to provide a combined plant of a gas turbine and a pulverized coal combustion device that effectively utilizes the exhaust gas from the gas turbine and reduces the generation of NOx.

[Means to solve the problem]

To achieve the above object, the present invention comprises a gas turbine, a pulverized coal boiler, an exhaust gas heat exchanger, a crusher, and a storage bin, the turbine exhaust gas from the gas turbine is passed through the exhaust gas heat exchanger. The boiler exhaust gas of the pulverized coal boiler is heated by the pulverized coal boiler, the high-temperature boiler exhaust gas is supplied to the pulverizer, the pulverized coal produced by the pulverizer is transported to a storage bin, and the pulverized coal is stored in the low-temperature turbine exhaust gas that has passed through the exhaust gas heat exchanger. It is characterized in that it is configured to transport pulverized coal in a bin to a pulverized coal boiler and burn it.

To achieve the aforementioned object, the present invention further comprises a gas turbine, a pulverized coal boiler, an exhaust gas heat exchanger, a crusher, and a storage bin, the turbine exhaust gas from the gas turbine being transferred to the exhaust gas heat exchanger. The boiler exhaust gas of the pulverized coal boiler is heated through the pulverized coal boiler, the high-temperature boiler exhaust gas is supplied to the crusher, the ultra-fine coal produced by the crusher is conveyed to the storage bin, and the low-temperature turbine exhaust gas is passed through the exhaust gas heat exchanger. The pulverized coal boiler is configured to supply pulverized coal to a pulverized coal boiler.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a first embodiment of the present invention, and FIG. 2 is a schematic configuration diagram for explaining the second embodiment.

In Fig. 1, 10 is a gas turbine, 2o is an EP ash collector, 30 is a chimney, 40 is a first fan, 45 is a second fan, 50 is a heat exchanger, 60 is a mill crusher, and 62 is a dust collector. , 65 is a storage bottle, 67 is a feeder, 70 is a denitrification device,
91 to 95 are dampers, 100, 110, 120 are gas turbine exhausts, 111 are gas turbine exhausts after temperature reduction, 11
2 is a pulverized coal conveyance line, 113 is a temperature adjustment line, 12
1 is the denitrification exhaust line, 123 is the secondary airline, 200
is the fresh air main pipe, 210 is the air for the ignition torch, 2
00 is after air, 300 is PAF fresh air, 5
00 and 501 are pulverized coal boiler exhaust gas, 510 is a drying line, 511 is a storage line, and 512 and 513 are vent system lines.

Gas turbine exhaust 100 (450-600°C) is
A portion 110 of the pulverized coal boiler exhaust gas 501 (100 to 150°C) is passed through a heat exchanger 50 to raise its temperature, and the return flow rate is adjusted so that the gas temperature at the inlet of the denitrification device is 350 to 450°C. It joins the turbine exhaust 120. In addition, the remaining amount is used as the pulverized coal conveyance line 112.
The pulverized coal fed by the feeder 67 from the storage bin 65 is conveyed to the pulverized coal burner, either mixed with fresh air 300 from F or alone.

On the other hand, the exhaust gas heated by the heat exchanger 50 (200
~370°C) is a mill 60 as a drying line 510.
Air is sent to the storage line 511. The enthalpy possessed by the drying line 510 is mainly used for drying the coal, and the temperature is reduced to about 120° C. in the storage line 511, so that heat loss to the outside air is minimized. Since the oxygen concentration in the boiler exhaust gas in the storage line 511 is basically 10% or less, there is no risk of spontaneous combustion or explosion of the pulverized coal no matter how much ultrafine coal is pulverized.

The denitrification exhaust line 121 that has passed through the denitrification device 70 is 300
The temperature is adjusted to ~400°C and sent to the wind box as secondary air (secondary airline 123). If the amount of fuel on the boiler side is larger than the amount of actually usable fuel corresponding to the oxygen flow rate in the gas turbine exhaust, a part or most of the necessary and sufficient amount of fresh air is mixed into the denitrification exhaust line 121 accordingly. and wind box gas (secondary airline 123). Depending on the type of coal, it may be difficult to maintain a self-flame, and in that case, a portion of the fresh air is supplied as after air 200 to a small capacity startup burner (preferably the same type of fuel gas as that of the gas turbine) that also serves as a star (up). is supplied intermittently or constantly (ignition torch air 210).

Coal is fed to the storage bin 65 through a bag filter 62, and extracted air 511' is fed into the atmosphere or/and into the boiler furnace. For example, when starting up a coal-fired boiler, the damper 95 is closed, the damper 94 is opened, and the bleed air 5 is
11" is vented to the atmosphere. After the boiler temperature rises, the bleed air 511
It is also possible to feed the boiler to the boiler furnace.

The difference between the second embodiment shown in FIG. 2 and the first embodiment is that the denitrification device 70 can be omitted by adopting a two-stage combustion method on the boiler furnace side, and that the denitrification device 70 can be omitted, and the gas Disturbance to the burner flame can be prevented by inputting the surplus of the turbine exhaust 111 (pulverized coal conveyance line 112) to the boiler furnace as a separate system independent from the coal burner throat.

〔Effect of the invention〕

Since the present invention has the above-described configuration, it is possible to effectively utilize the exhaust gas from the gas turbine and reduce the generation of NOx.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are schematic configuration diagrams of a composite plant according to each embodiment of the present invention. 10...-- Gas turbine, 70-- Denitrification device, 100° 110, 120-- Gas turbine exhaust, 111-1 Gas turbine exhaust after temperature reduction, 112・−・−・−Pulverized coal conveyance line, 501・−
-----1 Pulverized coal boiler exhaust gas, 510---Drying line, 1------1 Storage line.

Claims (2)

[Claims] (1) Equipped with a gas turbine, a pulverized coal boiler, an exhaust gas heat exchanger, a crusher, and a storage turbine, the turbine exhaust gas from the gas turbine is passed through the exhaust gas heat exchanger to raise the boiler exhaust gas of the pulverized coal boiler. The high-temperature boiler exhaust gas is supplied to a pulverizer, the pulverized coal produced by the pulverizer is transported to a storage bin, and the pulverized coal in the storage bin is transferred to the pulverized coal boiler using the low-temperature turbine exhaust gas that has passed through the exhaust gas heat exchanger. A complex plant, characterized in that it is configured to be transported to and combusted. (2) Equipped with a gas turbine, a pulverized coal boiler, an exhaust gas heat exchanger, a crusher, and a storage bin, the turbine exhaust gas from the gas turbine is passed through the exhaust gas heat exchanger to raise the boiler exhaust gas of the pulverized coal boiler. A complex plant characterized by being configured to heat the high-temperature boiler exhaust gas, supply the high-temperature boiler exhaust gas to a pulverizer, transport the pulverized coal produced by the pulverizer to a storage bin, and supply the exhaust gas to the pulverized coal boiler. .