JPH066901U - Gas uneven flow prevention device for exhaust heat recovery boiler - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to suppress the drift of the gas flowing into the exhaust heat recovery boiler. In an exhaust heat recovery boiler for recovering heat of exhaust gas from a gas turbine 1 as steam, a rectifier 10 for rectifying gas is provided upstream of the exhaust heat recovery boiler 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an exhaust heat recovery boiler that recovers the heat of exhaust gas from a gas turbine as steam, and more particularly to a gas drift prevention device for an exhaust heat recovery boiler that rectifies the gas flowing into the boiler.

[0002]

[Prior art]

 Since the gas discharged from the gas turbine is at a high temperature (for example, about 500 ° C), it is guided to the exhaust heat recovery boiler, and part of the heat is recovered by the boiler and cooled (for example, about 100 ° C). Open to the atmosphere.

The exhaust heat recovery boiler recovers a part of the heat of the exhaust gas and generates steam by this heat recovery. The generated steam is supplied to, for example, a steam turbine to rotate a turbine to generate electricity. Is done. The output of the steam turbine is about 30 to 35% or less of the total output, the amount of cooling water used is small, the equipment cost is low, and the operation is easy.

[0004]

[Problems to be solved by the device]

 By the way, since the above-mentioned exhaust heat recovery boiler is arranged downstream of the gas turbine, the exhaust gas from the gas turbine flows in as it is, so the heat collection at the inlet may become unstable. In other words, in the gas turbine, since the turbine is rotated by the gas, the gas becomes a swirling flow and is discharged from the turbine.Therefore, a nonuniform flow of gas may occur at the inlet of the exhaust heat recovery boiler, and the heat collection of the boiler may occur. Becomes unstable.

Therefore, the present invention has been made in consideration of such circumstances, and an object of the present invention is to provide an exhaust heat recovery boiler capable of suppressing uneven flow of gas flowing into the exhaust heat recovery boiler. It is to provide a gas drift prevention device.

[0006]

Means for Solving the Problems In order to achieve the above object, the present invention relates to an exhaust heat recovery boiler that recovers the heat of exhaust gas from a gas turbine as steam, on the upstream side of the exhaust heat recovery boiler, It is equipped with a rectifier that rectifies the gas.

[0007]

[Action]

 By providing a rectifier on the upstream side of the exhaust heat recovery boiler, the exhaust gas from the gas turbine is rectified by the rectifier and then flows into the exhaust heat recovery boiler, which suppresses gas drift in the boiler. . For this reason, the heat collection of the boiler is almost non-uniform, and the boiler performance becomes stable.

[0008]

【Example】

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

In FIG. 1, reference numeral 1 denotes a gas turbine, and an exhaust gas duct 3 for guiding the gas discharged from the turbine 1 to a chimney 2 is connected to the gas turbine 1.

An exhaust heat recovery boiler 4 that recovers a part of the heat of the gas as steam is provided in the exhaust gas duct 3. The exhaust heat recovery boiler 4 is mainly composed of a economizer 5, a drum 6, an evaporator 7 and a superheater 8. The economizer 5, the evaporator 7 and the superheater 8 are arranged along the gas flow direction. Sequentially arranged in the exhaust gas duct 3. The economizer 5 preheats the water supply from the water supply pipe 9, and the preheated water is guided to the drum 6. An evaporator 7 is connected to the drum 6, and the evaporator 7 generates steam by the heat of the gas in the duct, and this steam flows into the drum 6. The drum 6 separates steam and water into steam and water, and the steam is superheated via the superheater 8.

As shown in FIGS. 1 and 2, the exhaust gas duct 3 on the upstream side of the exhaust heat recovery boiler 4 is provided with a rectifying plate 10 as a rectifier for rectifying gas. The straightening vane 10 is provided with a plurality of holes (for example, holes having a diameter of about 5 mm) 11 and is formed as a perforated plate. Exhaust gas from the gas turbine 1 is straightened by the straightening vane 10 and then to the boiler 4. It is supposed to flow in. The rectifying plate 10 is not limited to one and may be arranged so as to be stacked on the exhaust gas duct 3. Further, the rectifier is not limited to the rectifier plate 10, but may be any rectifier as long as it can rectify the exhaust gas from the gas turbine 1. As shown in (a), (b) and (c), the round bar 12, the plate 13, the corrugated plate 14 and the like may constitute a rectifier.

Next, the operation of this embodiment will be described.

Exhaust gas of high temperature (eg, about 500 ° C.) from the gas turbine 1 enters the exhaust gas duct 3, and its flow is first rectified by the rectifying plate 10 and then flows into the exhaust heat recovery boiler 4. There, part of the heat of the gas is recovered and cooled (for example, about 100 ° C.), and then released from the chimney 2 to the atmosphere. In the exhaust heat recovery boiler 4, steam is generated by heat recovery, and this steam is supplied to, for example, a steam turbine.

Since the exhaust gas flowing into the exhaust heat recovery boiler 4 is rectified by the flow straightening plate 10, even if it becomes a swirling flow from the gas turbine 1 and flows into the duct 3, when it flows into the boiler 4, it is converted into gas. Uneven flow will be suppressed. For this reason, in the superheater 8 of the boiler 4, etc., there is no deviation of the gas in the vertical and horizontal directions, and the heat collection in the superheater 8 etc. is performed in a well-balanced manner. As a result, the heat collection of the boiler 4 becomes uniform and its performance becomes stable. When a denitration device (a device that uses ammonia to reduce NOx of exhaust gas in the presence of a catalyst) is installed, although not shown, for example, the superheater 8 and the evaporator 7 of the exhaust heat recovery boiler 4 are not shown. Since the exhaust gas that flows between the denitration equipment and the denitration equipment is rectified, it flows evenly in the denitration equipment, so it is sufficiently denitrated and the NOx imbalance of gas at the outlet of the denitration equipment can be suppressed. it can.

Further, as shown by a dotted line in FIG. 1, a rectifier (rectifying plate 10) may be provided on the exhaust gas duct 3 downstream of the exhaust heat recovery boiler 4. With this configuration, when the duct 3 at the outlet of the boiler 4 is short (when the chimney 2 is near the boiler 4), the flow of exhaust gas tends to be biased to the upper part of the duct 3 due to the chimney effect, but is regulated by the straightening plate 10. Therefore, the gas flows uniformly into the chimney 2.

[0016]

[Effect of device]

 In summary, according to the present invention, since the rectifier is provided on the upstream side of the exhaust heat recovery boiler, it is possible to suppress the uneven flow of the gas flowing into the exhaust heat recovery boiler and to exhibit the excellent effect that the boiler performance becomes stable.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a perspective view showing an example of a rectifier of the present invention.

FIG. 3 is a side view showing another example of the rectifier of the present invention.

[Explanation of symbols]

 1 Gas turbine 4 Exhaust heat recovery boiler 10 Rectifier plate (rectifier)

Claims (1)

[Scope of utility model registration request] 1. An exhaust heat recovery boiler for recovering heat of exhaust gas from a gas turbine as steam, wherein a rectifier for rectifying gas is provided upstream of the exhaust heat recovery boiler. Gas drift prevention device.