Device applied to quick start of gas-steam combined cycle unit

Abstract

The utility model discloses a device for quickly starting a gas-steam combined cycle unit, which comprises an outer cylinder and an inner cylinder, a support for supporting the outer cylinder is fixedly connected to the bottom of the outer cylinder, an insulating bush is arranged between the inner cylinder and the outer cylinder, a water inlet pipe and a water outlet pipe which are communicated with an inner cavity and the inner cylinder are arranged on two sides of the outer cylinder, and a gas outlet is arranged at the upper end of the inner cylinder. The upper end of the outer cylinder is provided with an air outlet pipe in butt joint with the air outlet, the upper end of the outer cylinder is fixedly connected with a support, an inner cavity of the support is movably provided with multiple sets of high-voltage electrodes, and the high-voltage electrodes movably penetrate through the outer cylinder and the inner cylinder and then extend into an inner cavity of the inner cylinder. Compared with a gas-fired boiler, the electrode boiler designed by the utility model has the advantages that the starting speed is high, the steam production performance is excellent, the automation degree is higher, the quick starting requirement of an F-level gas-steam combined cycle unit can be better met, the whole system and the boiler body of the electrode boiler are simpler in structure, and a gas-fired system, a hearth, a flue and a heat exchange tube bundle are avoided; and the operation and maintenance cost of the whole set of equipment is lower.

Description

Technical Field

[0001] The utility model relates to the relevant field of high-pressure boilers, and in particular to a device used for rapid starting of a gas-steam combined cycle unit. Background Art

[0002] At present, the F-class single-shaft gas-steam combined power generation units in use in China require a certain amount of heating steam from the gas steam boiler to enter the turbine exhaust cylinder cooling and shaft seal sealing steam during the startup phase, so that the steam turbine can meet the startup conditions. In the market, most of the gas steam boilers in use use low-nitrogen burners + flue gas recirculation technology. On the one hand, the ratio of gas and air is controlled to meet the flue gas emission index requirements. On the other hand, superheated steam with a certain pressure and temperature is generated through furnace combustion heat radiation and flue gas heat transfer to meet the steam demand required for the startup process of the gas-steam combined cycle unit. With the changes in the operation mode of the power market, higher requirements are put forward for the rapid start-up of gas-steam combined power generation units. The rapid start-up performance of the supporting gas steam boiler will directly affect the rapid start-up time of the gas turbine generator set. Optimizing the supporting steam boiler is necessary for the gas turbine generator set; with the continuous improvement of the requirements of local environmental protection departments for the flue gas emission index of gas steam boilers, its low-nitrogen burner characteristics and flue gas emission index bring certain challenges.

[0003] At present, environmental protection departments in some regions have raised the emission index of industrial gas boilers, that is, NOx is less than 30ug / m³. In recent years, the domestic low-nitrogen burners have been in the market for a relatively short time, and their low-nitrogen combustion performance has yet to be verified. In addition, due to its principle, structure and heat transfer characteristics, the gas-steam boiler has a relatively slow steam production speed, which will affect the rapid startup capability of the gas-steam combined cycle unit. Utility Model Content

[0004] The utility model designs a device for rapid startup of a gas-steam combined cycle unit, thereby solving the technical problems raised in the background technology and proposing the following technical solutions:

[0005] A device for rapid start-up of a gas-steam combined cycle unit comprises an outer tube and an inner tube, wherein a support for supporting the outer tube is fixedly connected to the bottom of the outer tube, an insulating bushing is arranged between the inner tube and the outer tube, a water inlet pipe and a water outlet pipe connecting the inner cavity and the inner tube are arranged on both sides of the outer tube, an air outlet is arranged at the upper end of the inner tube, and an air outlet pipe butted to the air outlet is arranged at the upper end of the outer tube, a bracket is fixedly connected to the upper end of the outer tube, a plurality of groups of high-voltage electrodes are movably arranged in the inner cavity of the bracket, and the high-voltage electrodes movably penetrate the outer tube and the inner tube and then extend to the inner cavity of the inner tube.

[0006] Preferably, the connecting ends of the water inlet pipe, the water outlet pipe and the air outlet pipe are all provided with sealing gaskets.

[0007] Preferably, an electric heater is also provided at the connection position between the bottom of the air outlet pipe and the outer cylinder.

[0008] Preferably, a mounting plate is movably provided in the inner cavity of the bracket, and a plurality of groups of high-voltage electrodes are fixedly connected to the bottom of the mounting plate, and an electric push rod for driving the mounting plate to move up and down is fixedly connected to the upper end of the bracket.

[0009] Preferably, the inner walls of the outer cylinder and the inner cylinder are both fixedly provided with electrode guide sleeves, and the high-voltage electrode is movably inserted into the electrode guide sleeves.

[0010] Compared with the prior art, the beneficial effects of the utility model are:

[0011] The utility model adopts electrode heating technology. The high-voltage electrode of the electrode boiler is inserted into the water and quickly heated by a high-power current to generate saturated steam of a certain pressure, temperature and flow rate. The saturated steam is heated to superheated steam by the electric heater at the boiler outlet for cooling and sealing of the gas-steam combined generator set. In addition, an inner and outer tube structure is adopted. The inner and outer tubes are insulated, and the inner tube wall is the neutral point, ensuring that the boiler shell always keeps the voltage lower than the safe voltage. When the outer tube is grounded, the neutral point does not change the property of the ungrounded neutral point. In addition, the inner tube and the outer tube are connected by insulating materials to ensure that the boiler shell voltage is always within the safe voltage range when the electrical switch fails. In summary, compared with the gas boiler, the electrode boiler designed by the utility model has a fast starting speed, excellent steam production performance, and a high degree of automation. It can better meet the rapid start-up requirements of the F-class gas-steam combined cycle unit, and the entire system and boiler body structure of the electrode boiler are simpler, without a gas system, furnace, flue, or heat exchange tube bundle, and the operation and maintenance costs of the entire set of equipment are lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the external structure of the utility model;

[0013] Figure 2 This is a schematic diagram of the internal structure of the utility model;

[0014] Figure 3 It is an enlarged schematic diagram of the structure at point A of the utility model.

[0015] In the figure: 1-outer cylinder, 2-support, 3-inner cylinder, 4-insulating bushing, 5-water inlet pipe, 6-water outlet pipe, 7-air outlet, 8-air outlet pipe, 801-electric heater, 9-bracket, 901-mounting plate, 902-electric push rod, 10-high voltage electrode, 1001-electrode guide sleeve. DETAILED DESCRIPTION

[0016] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0017] In the description of the present invention, "plurality" means two or more than two, unless otherwise clearly and specifically defined.

[0018] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0020] Reference Manual Attached Figure 1-3A device for rapid start-up of a gas-steam combined cycle unit comprises an outer tube 1 and an inner tube 3. A support 2 for supporting the outer tube 1 is fixedly connected to the bottom of the outer tube 1, an insulating bushing 4 is arranged between the inner tube 3 and the outer tube 1, and a water inlet pipe 5 and a water outlet pipe 6 communicating with the inner cavity of the inner tube 3 are arranged on both sides of the outer tube 1. An air outlet 7 is arranged at the upper end of the inner tube 3, and an air outlet pipe 8 connected to the air outlet 7 is arranged at the upper end of the outer tube 1. An electric heater 801 is also arranged at the connection position between the bottom of the air outlet pipe 8 and the outer tube 1, a bracket 9 is fixedly connected to the upper end of the outer tube 1, and a plurality of groups of high-voltage electrodes 10 are movably arranged in the inner cavity of the bracket 9, and the high-voltage electrodes 10 movably penetrate the outer tube 1 and the inner tube 3 and then extend to the inner cavity of the inner tube 3. Based on the above structure, the device designed by the utility model adopts electrode heating technology, uses high-voltage electrodes 10 to be inserted into the water inside the inner tube 3, and quickly heats it through high-power current to generate saturated steam with a certain pressure, temperature, and flow rate, and uses the outlet 7 in the inner tube 3 to discharge steam, and the electric heater 801 at the outlet position of the outlet pipe 8 heats the saturated steam to superheated steam for cooling and sealing of the gas-steam combined generator set. It has a fast overall startup speed, excellent steam production performance, and a high degree of automation, and can better meet the rapid startup requirements of F-class gas-steam combined cycle units.

[0021] Among them, the connection ends of the water inlet pipe 5, the water outlet pipe 6, and the air outlet pipe 8 are all provided with sealing gaskets to increase the sealing effect of the pipeline connection.

[0022] Among them, a mounting plate 901 is movably provided in the inner cavity of the bracket 9, and multiple groups of high-voltage electrodes 10 are fixedly connected to the bottom of the mounting plate 901, and an electric push rod 902 for driving the mounting plate 901 to move up and down is fixedly connected to the upper end of the bracket 9. An electrode guide sleeve 1001 is fixedly penetrated through the inner walls of the outer cylinder 1 and the inner cylinder 3, and the high-voltage electrode 10 is movably penetrated and inserted into the electrode guide sleeve 1001. The movable plate 901 inside the bracket 9 is pushed by the electric push rod 902 to drive the high-voltage electrode 10 to move down along the electrode guide sleeve 1001 and be inserted into the inner cylinder 3. It is quickly heated by high-power current to generate saturated steam with a certain pressure, temperature and flow rate, and the electrode guide sleeve 1001 is made of insulating material.

[0023] In the description of the present invention, it is necessary to understand that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

Claims

1. A device for rapid startup of a gas-steam combined cycle unit, comprising an outer cylinder (1) and an inner cylinder (3), characterized in that: The bottom of the outer tube (1) is fixedly connected to a support (2) for supporting it, an insulating bushing (4) is arranged between the inner tube (3) and the outer tube (1), a water inlet pipe (5) and a water outlet pipe (6) communicating with the inner cavity of the inner tube (3) are arranged on both sides of the outer tube (1), an air outlet (7) is arranged at the upper end of the inner tube (3), and an air outlet pipe (8) connected to the air outlet (7) is arranged at the upper end of the outer tube (1), and a bracket (9) is fixedly connected to the upper end of the outer tube (1), and a plurality of groups of high-voltage electrodes (10) are movably arranged in the inner cavity of the bracket (9), and the high-voltage electrodes (10) movably penetrate the outer tube (1) and the inner tube (3) and then extend to the inner cavity of the inner tube (3).

2. The device for rapid startup of a gas-steam combined cycle unit according to claim 1, characterized in that: The connection ends of the water inlet pipe (5), the water outlet pipe (6) and the air outlet pipe (8) are all provided with sealing gaskets.

3. The device for rapid startup of a gas-steam combined cycle unit according to claim 2, characterized in that: An electric heater (801) is also provided at the connection position between the bottom of the air outlet pipe (8) and the outer cylinder (1).

4. The device for rapid startup of a gas-steam combined cycle unit according to claim 3, characterized in that: A mounting plate (901) is movably disposed in the inner cavity of the bracket (9), and a plurality of groups of high-voltage electrodes (10) are fixedly connected to the bottom of the mounting plate (901). An electric push rod (902) for driving the mounting plate (901) to move up and down is fixedly connected to the upper end of the bracket (9).

5. The device for rapid startup of a gas-steam combined cycle unit according to claim 4, characterized in that: An electrode guide sleeve (1001) is fixedly provided through the inner walls of the outer cylinder (1) and the inner cylinder (3), and the high-voltage electrode (10) is movably inserted through the electrode guide sleeve (1001).

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