JPH0960529A - Unburned Gas Purging Mechanism of Exhaust System in Gas Turbine Complex - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] Unburned exhaust system in a gas turbine complex facility capable of shortening the purge time without increasing the facility cost and increasing the size of the facility and improving the operation efficiency. A gas purging mechanism is provided. An enclosure 20 in which a gas turbine 10 is arranged and an intake duct 30 are connected by a ventilation duct 50 having a ventilation fan 51, and the ventilation duct 50 and an exhaust duct 40 are connected by a purge passage 70. The purge passage 70 is provided with an openable / closable damper 72 that can be opened and closed.
1 blows air from the ventilation duct 50 to the exhaust duct 40 via the purging passage 70.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unburned gas purge mechanism for an exhaust system in a gas turbine complex facility in which an exhaust passage of a gas turbine is connected to an exhaust gas utilizing device.

[0002]

2. Description of the Related Art A gas turbine combined facility for cogeneration with heat and power, which drives a generator by a gas turbine using a gas fuel such as natural gas to generate electric power, and recovers waste heat thereof for heating and cooling or hot water supply, so-called cogeneration In the facility, unburned fuel gas may remain in the exhaust passage and the exhaust gas utilization device (exhaust system) at the time of stop, and it is necessary to remove this by purging at the time of start.

Usually, a gas turbine is idled by a starter to blow air only to replace the air in the exhaust system.

The gas turbine is usually arranged in a shielding container for shielding noise and heat, and the shielding container has a ventilation supply passage branched at one end thereof from an intake passage for introducing air into the gas turbine. And a ventilation exhaust duct is connected to the other end, and the air in the intake passage is introduced into the shielding container by the ventilation fan provided at the branch of the ventilation supply passage from the intake passage, and the exhaust duct for ventilation is also connected. The inside of the shielded container is ventilated and cooled.

[0005]

However, in the conventional method of idling the gas turbine by the starter and purging the exhaust system as in the above-mentioned conventional method, a large amount of air is not obtained, and the exhaust system (such as the cogeneration system) is not obtained. When the volume of the exhaust gas utilization equipment) is large, it takes a lot of time, and there is a problem that the efficiency is extremely low particularly in the equipment of the operation form in which start / stop is repeated every day. That is, purging requires ventilation of three times or more of the exhaust system volume, and 20 to 30 minutes are required for air blowing using a gas turbine.

[0006] Further, in the case where the dedicated blower is provided, the purging time can be shortened, but there is a problem that the facility cost increases and a space for it is required, so that the entire facility becomes large.

The present invention has been made to solve the above problems, and can shorten the purge time and improve the operating efficiency without increasing the equipment cost and increasing the equipment size. It is an object of the present invention to provide an unburned gas purging mechanism for an exhaust system in a gas turbine complex facility that can be used.

[0008]

An unburned gas purging mechanism for an exhaust system in a gas turbine facility of the present invention that achieves the above object is a gas turbine complex facility in which an exhaust passage of a gas turbine is connected to an exhaust gas utilization device. The gas turbine is arranged in a shielded container, and the intake passage and the shielded container are connected by a ventilation supply passage provided with a blowing means, and ventilation air is introduced into the shielded container through the ventilation supply passage. The ventilation supply passage and the exhaust passage are connected by a purge passage having an opening / closing means.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a conceptual configuration diagram of a gas turbine portion to which an embodiment of an unburned gas purging mechanism for an exhaust system in a gas turbine complex facility according to the present invention is applied.

The gas turbine 10 is arranged so as to be surrounded by an enclosure 20 as a shielding container, and the enclosure 20 has an intake duct 30 as an intake passage, an exhaust duct 40 as an exhaust passage, and a ventilation branching from the intake duct 30. A ventilation duct 50 as a supply passage and a ventilation exhaust duct 60 are connected.

The enclosure 20 is partitioned into an intake chamber 21 and a turbine chamber 22. The gas turbine 10 is arranged in the turbine chamber 22 and its intake port 11 is open to the intake chamber 21. The rotary shaft 12 of the gas turbine 10 projects to the side opposite to the intake side of the enclosure 20 and is connected to a generator (not shown) to drive it rotationally.

The intake duct 30 is provided with an intake filter 31 at its inlet and a sound absorbing material 32 inside, and is connected to the intake chamber 21 of the enclosure 20.

The exhaust duct 40 is directly connected to the exhaust port of the gas turbine 10 and extends outside the enclosure 20, and the other end is connected to an exhaust gas utilization device such as a boiler (not shown).

The ventilation duct 50 connects the upstream side of the joint of the intake duct 30 to the enclosure 20 and the turbine chamber 22 of the enclosure 20. A ventilation fan 51 as a blower is provided near the opening to the intake duct 30, and a fire extinguishing damper 52 is provided at the opening to the turbine chamber 22 so that the opening can be opened and closed. . A purging passage 70 is connected in the middle of the ventilation duct 50, and the other end is connected to the vicinity of the protruding portion of the exhaust duct 40 from the enclosure 20. An actuator 71 is provided in the purging passage 70.
An opening / closing damper 72 is provided as an opening / closing unit that can be slid to open and close the purging passage 70.

The ventilation exhaust duct 60 is connected to the rear end side of the turbine chamber 22 and has the other end open to the outside.

In the gas turbine equipment having the above structure, the gas turbine 10 sucks the air reaching the intake chamber 21 of the enclosure 20 through the intake duct 30 and burns the fuel gas supplied through a path (not shown). The exhaust gas is supplied to the exhaust gas utilization equipment connected through the exhaust duct 40. Further, during normal operation, the fire-extinguishing damper 52 provided in the opening of the ventilation supply duct 50 to the enclosure 20 (turbine chamber 22) is opened, and
The opening / closing damper 72 of the purging passage 70 is closed, and ventilation air is introduced from the intake duct 30 into the ventilation duct 50 by driving the ventilation fan 51, and this ventilation air is supplied into the turbine chamber 22 of the enclosure 20. And exhausted from the ventilation and exhaust ducts, the turbine chamber 22
Ventilate the inside. The fire-extinguishing damper 52 is closed in an emergency when a fire occurs in the gas turbine 10 so that the gas turbine chamber 22 is sealed.

For purging the exhaust system at the time of starting the gas turbine, the gas turbine 10 is spun by a starter (not shown), and the fire-extinguishing damper 5 as shown in FIG.
2 is closed and the opening / closing damper 72 of the purging passage 70 is opened so that the ventilation duct 50 and the exhaust duct 40 are connected to the purging passage 7
The ventilation fan 51 is driven in a state where the ventilation fan 51 communicates with each other. As a result, the air can be quickly purged by the air blown by the gas turbine 10 and the air blown by the ventilation fan 51 to the exhaust duct 40 via the ventilation duct 50 and the purge passage 70. That is, since the amount of air blown by the ventilation fan 51 is about 3 to 4 times the amount of air blown by the idle rotation of the gas turbine 10, the purge time can be shortened to about 1/4 of the purge time by the idle rotation of the gas turbine 10. It is a thing.

After the purging is completed, the fire extinguishing damper 52 is opened and the opening / closing damper 72 of the purging passage 70 is closed.
The supply of fuel gas to the gas turbine 10 is started and ignited to start the operation.

[0019]

As described above, in the unburned gas purging mechanism of the exhaust system in the gas turbine combined facility according to the present invention, the ventilation fan for supplying the ventilation air into the shielding container during operation is purged at the start of operation. It is possible to shorten the purge time. This allows
The operation efficiency of the equipment can be improved, and particularly in the equipment where start / stop is repeated every day, a remarkable efficiency improvement effect can be obtained.

Moreover, since a dedicated blower is not added, the cost of the equipment and the size of the equipment are not increased.

[Brief description of drawings]

FIG. 1 is a conceptual configuration diagram during normal operation of a gas turbine part to which an embodiment of an unburned gas purging mechanism for an exhaust system in a gas turbine complex facility according to the present invention is applied.

FIG. 2 is a conceptual configuration diagram when a gas turbine portion is purged.

[Explanation of symbols]

 10 Gas Turbine 20 Enclosure (Shielding Container) 30 Intake Duct (Intake Passage) 40 Exhaust Duct (Exhaust Passage) 50 Ventilation Duct (Ventilation Supply Passage) 51 Ventilation Fan (Blower) 70 Purge Passage 72 Opening / Closing Damper (Opening / Closing Means)

Claims (1)

[Claims] 1. A gas turbine composite facility comprising an exhaust passage of a gas turbine connected to an exhaust gas utilization device, wherein the gas turbine is arranged in a shielding container, and the intake passage and the shielding container are blown. A ventilation supply passage provided with a means, and the ventilation air is supplied into the shielding container through the ventilation supply passage, wherein the ventilation supply passage and the exhaust passage form an opening / closing means. An unburned gas purging mechanism for an exhaust system in a gas turbine complex facility, which is configured to be connected by a purge passage provided therein.