An economizer structure for a waste heat boiler of a combustion engine

Abstract

This utility model discloses an economizer structure for a gas turbine waste heat boiler. The economizer inlet header and economizer outlet header are connected by heat exchanger tubes. The economizer inlet header and economizer intermediate connecting header are connected by a row of single-pass front-end heat exchanger tubes. The economizer intermediate connecting header is connected to two rows of single-pass front-end heat exchanger tubes, one inlet and one outlet. The single-pass front-end heat exchanger tubes are connected to each other and to the single-pass end heat exchanger tubes. The single-pass end heat exchanger tubes are connected to the economizer end connecting header. The economizer end connecting header and economizer outlet header are connected by double-pass heat exchanger tubes. When the combined cycle unit load changes, the orifice plate increases the flow resistance of the working fluid in the heat exchanger, increases the saturation temperature of the water, and reduces vaporization. The double-pass heat exchanger tubes increase the cross-sectional area of ​​the working fluid in the economizer, quickly removing the vaporized working fluid and preventing overheating and tube rupture of the economizer heat exchanger tubes, thus improving the service life of the boiler.

Description

Technical Field

[0001] This utility model relates to the field of waste heat utilization technology, and in particular to an economizer structure for a gas turbine waste heat boiler. Background Technology

[0002] In a combined cycle power system, a waste heat boiler is used to recover waste heat from the exhaust gas of the gas turbine, generating steam to drive a steam turbine for power generation. Combined cycle units are generally used for peak shaving, with rapid start-up and shutdown, frequent load changes, and fluctuating exhaust parameters due to seasonal or ambient temperature variations. Because the economizer's hot face is fixed, vaporization easily occurs at the economizer end when the gas turbine load or exhaust parameters change in a combined cycle unit. This causes a sharp increase in the working fluid volume within the economizer. However, the flow cross-section of a conventional fixed-return economizer remains constant throughout the entire process, preventing the vaporized gas from being promptly removed. This leads to insufficient cooling and localized overheating and tube rupture at the economizer's hot face, severely impacting the boiler's service life. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model designs an economizer structure for a gas turbine waste heat boiler.

[0004] The present invention adopts the following technical solution:

[0005] An economizer structure for a gas turbine waste heat boiler includes an economizer inlet header, an economizer outlet header, an economizer intermediate connecting header, and an economizer end connecting header. The economizer inlet header and the economizer outlet header are connected by heat transfer surface tubes. The heat transfer surface tubes include a single-pass front heat transfer surface tube, a single-pass end heat transfer surface tube, and a double-pass heat transfer surface tube.

[0006] The economizer inlet header and the economizer intermediate connecting header are connected by a row of single-pass front-end heat exchanger tubes. The economizer intermediate connecting header is connected to two rows of single-pass front-end heat exchanger tubes, one inlet and one outlet. The single-pass front-end heat exchanger tubes are connected to each other and to the single-pass end heat exchanger tubes. The single-pass end heat exchanger tubes are connected to the economizer end connecting header. The economizer end connecting header and the economizer outlet header are connected by double-pass heat exchanger tubes.

[0007] Preferably, the single-pass front heating surface tubes and the single-pass end heating surface tubes are connected by elbows.

[0008] Preferably, a throttling orifice plate is provided at the outlet end of the single-pass front-end heated surface tube.

[0009] Preferably, the working fluid enters from the economizer inlet header, flows sequentially through the single-pass front heating surface tubes and the economizer intermediate connecting header, and finally enters the economizer end connecting header from the single-pass end heating surface tubes. The working fluid entering the economizer end connecting header simultaneously passes through two rows of pipes of the double-pass heating surface tubes into the economizer outlet header, and is led out by the outlet pipe of the economizer outlet header.

[0010] The beneficial effects of this utility model are: (1) When the load of the combined cycle unit changes, the throttling orifice plate can increase the flow resistance of the working fluid in the hot surface, increase the saturation temperature of the water, and reduce the vaporization phenomenon; (2) The last two rows of tubes are arranged in a double-pass structure, which increases the cross-sectional area of ​​the working fluid in the economizer, quickly removes the vaporized working fluid, avoids overheating and tube bursting of the economizer hot surface tubes, and improves the service life of the boiler. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model;

[0012] Figure 2 yes Figure 1 A partial sectional view at point V in the middle;

[0013] In the diagram: 1. Economizer inlet header, 2. Economizer outlet header, 3. Economizer intermediate connecting header, 4. Economizer end connecting header, 5. Single-pass front-end heating surface tube, 6. Single-pass end heating surface tube, 7. Double-pass heating surface tube, 8. Orifice plate, 9. Elbow. Detailed Implementation

[0014] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings:

[0015] Example: Figure 1 and Figure 2 As shown, an economizer structure for a gas turbine waste heat boiler mainly includes an economizer inlet header 1, an economizer outlet header 2, an economizer intermediate connecting header 3, an economizer end connecting header 4, and single-pass front-end heat transfer tubes 5, single-pass end heat transfer tubes 6, and double-pass heat transfer tubes 7.

[0016] The economizer inlet header 1 and the economizer intermediate connecting header 3 are connected by a row of single-pass front-end heat exchanger tubes 5. The economizer intermediate connecting header is connected to two rows of single-pass front-end heat exchanger tubes 5, one inlet and one outlet. The single-pass front-end heat exchanger tubes 5 are connected to each other and to the single-pass end heat exchanger tubes 6 via elbows 9. The single-pass front-end heat exchanger tubes 5 are connected to the economizer end connecting header 4, and a throttling orifice plate 8 is installed at the outlet end of the single-pass front-end heat exchanger tubes 5. The economizer end connecting header 4 and the economizer outlet header 2 are connected by double-pass heat exchanger tubes 7.

[0017] During operation of the economizer structure of this gas turbine waste heat boiler, the high-temperature flue gas discharged from the gas turbine flows sequentially through the outer sides of the double-pass heating surface tubes 7, the single-pass end heating surface tubes 6, and the single-pass front heating surface tubes 5. The working fluid enters from the economizer inlet header 1, flows sequentially through the single-pass front heating surface tubes 5 and the economizer intermediate connecting header 3, and finally enters the economizer end connecting header 4 through the single-pass end heating surface tubes 6. The working fluid entering the economizer end connecting header 4 simultaneously passes through the two rows of pipes of the double-pass heating surface tubes 7 into the economizer outlet header 2, and is led out through the outlet pipe of the economizer outlet header 2. A throttling orifice plate 8 is installed at the outlet end of the single-pass end heating surface tubes 6.

[0018] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. An economizer structure for a gas turbine waste heat boiler, comprising an economizer inlet header, an economizer outlet header, an economizer intermediate connecting header, and an economizer end connecting header, wherein the economizer inlet header and the economizer outlet header are connected by heat-receiving surface tubes, characterized in that, The heated surface tubes include a single-pass front heated surface tube, a single-pass end heated surface tube, and a double-pass heated surface tube; The economizer inlet header and the economizer intermediate connecting header are connected by a row of single-pass front-end heat exchanger tubes. The economizer intermediate connecting header is connected to two rows of single-pass front-end heat exchanger tubes, one inlet and one outlet. The single-pass front-end heat exchanger tubes are connected to each other and to the single-pass end heat exchanger tubes. The single-pass end heat exchanger tubes are connected to the economizer end connecting header. The economizer end connecting header and the economizer outlet header are connected by double-pass heat exchanger tubes.

2. The economizer structure for a gas turbine waste heat boiler according to claim 1, characterized in that, The single-pass front-end heating surface tubes and the single-pass end-end heating surface tubes are connected by elbows.

3. The economizer structure for a gas turbine waste heat boiler according to claim 1, characterized in that, A throttling orifice plate is provided at the outlet end of the single-pass front-end heated surface tube.

4. The economizer structure for a gas turbine waste heat boiler according to claim 1, characterized in that, The working fluid enters from the economizer inlet header, flows sequentially through the front heating surface tubes of the single-pass heat exchanger and the intermediate connecting header of the economizer, and finally enters the end connecting header of the economizer through the end heating surface tubes of the single-pass heat exchanger. The working fluid entering the end connecting header of the economizer simultaneously passes through two rows of pipes of the double-pass heat exchanger and enters the economizer outlet header, and is led out by the outlet pipe of the economizer outlet header.

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