Quickly-started steam turbine

Abstract

The invention discloses a quick-start steam turbine, and belongs to the technical field of quick start of heat engines. Comprising a turbine system, a heating device, a water supply system and a starting device, the turbine system comprises a high-pressure fan, a gas conveying pipe, a heater, a steam inlet pipe, a turbine and a steam exhaust pipe which are connected in sequence; the heating device comprises a furnace, a combustion-supporting gas inlet pipe and a three-way regulating valve; the water supply system comprises a water tank, a water pipe, a water valve and a water nozzle; the starting device comprises an air storage cylinder, a starting valve and a connecting pipe which are connected in sequence. The technical problem that a traditional steam turbine is long in starting time is solved, and meanwhile the output power of the device is improved and adjusted.

Description

Technical Field

[0001] The invention relates to the technical field of rapid start-up of thermal engines, in particular to a rapid start-up steam turbine. Background Art

[0002] As a power plant for thermal power plants and large ships, steam turbines have a big disadvantage of slow start-up, which is time-consuming and consumes a lot of fuel. This disadvantage is not a big problem for thermal power plants because thermal power plants do not need to start frequently, but it is very delayed for ships. According to data, the Liaoning ship, which uses steam turbines, needs to heat 60 tons of cold water in the steam boiler for 48 hours before it can be fully started in a cold state. Even in standby mode, it takes several hours to maximize the operating efficiency of the power system, which is not a short time. The reason why steam turbines start slowly lies in their heaters. First, the contact area between the boiler and the flue gas is small, and the heat transfer efficiency is low. Second, a large amount of water in the boiler must be heated to the boiling point (the boiling point of water under high pressure is much higher than 100°C) before it can be vaporized, and then the saturated steam must be heated to become superheated steam to do work. Since the specific heat and vaporization heat of water are both large, the process of turning cold water into superheated steam consumes a lot of fuel and the heating time is long. Therefore, it is necessary to improve steam turbines, shorten the start-up time, and reduce fuel consumption. Summary of the invention

[0003] The purpose of the present invention is to provide a quick-start steam turbine to solve the technical problem of long start-up time of traditional steam turbines in view of the above problems.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A quick-start steam turbine comprises a turbine system, a heating device, a water supply system and a starting device;

[0006] The turbine system comprises a high-pressure fan, an air delivery pipe, a heater, a steam inlet pipe, a steam turbine and a steam exhaust pipe which are connected in sequence, wherein one end of the air delivery pipe is connected to the air outlet of the high-pressure fan, and the other end is connected to one end of the heater; the heater is arranged in the heating device, and the other end of the heater passes through the heating device and is connected to one end of the steam inlet pipe, the other end of the steam inlet pipe is connected to the steam inlet of the steam turbine, the steam exhaust of the steam turbine is connected to one end of the steam exhaust pipe, and the steam turbine is connected to the high-pressure fan;

[0007] The heating device comprises a furnace, a combustion-supporting gas inlet pipe and a three-way regulating valve, wherein the inlet end of the three-way regulating valve is connected to one end of the exhaust steam pipe, one outlet end of the three-way regulating valve is connected to one end of the combustion-supporting gas inlet pipe, the other outlet end of the three-way regulating valve is connected to one end of the exhaust steam pipe, the other end of the combustion-supporting gas inlet pipe is connected to the combustion-supporting gas inlet end of the furnace, and the three-way regulating valve can adjust the amount of combustion-supporting gas entering the furnace as needed;

[0008] The water supply system includes a water tank, a water pipe, a water valve and a water nozzle. One end of the water pipe is connected to the water tank, and the other end is connected to the water nozzle. The water valve is installed on the water pipe and controls the on-off of the water pipe and the water flow rate. The water nozzle is arranged at the air inlet of the high-pressure fan. The water supply system can deliver mist water to the turbine system.

[0009] The starting device comprises an air storage cylinder, a starting valve and a connecting pipe which are connected in sequence. The starting valve is installed at the air inlet and outlet ends of the air storage cylinder. One end of the connecting pipe is connected to the starting valve, and the other end is connected to the air supply pipe in a three-way shape.

[0010] Furthermore, an openable and closable cover is provided at the air inlet of the high-pressure blower.

[0011] Furthermore, a check valve is installed between the high-pressure blower and the gas pipe, and the check valve prevents the fluid from flowing from the gas pipe into the high-pressure blower.

[0012] Furthermore, the water supply system also includes an economizer, which is installed in the middle of the water pipe. The water pipe is connected to the water inlet and outlet of the economizer. The economizer is installed at the end of the heating device to heat the water using the waste heat of the flue gas.

[0013] Furthermore, the heater is installed in the furnace in the shape of a multi-layer coil.

[0014] Due to the adoption of the above technical solution, the present invention has the following beneficial effects:

[0015] 1. The present invention starts quickly, and can start quickly even in a cold state; first, turn on the heating device to ignite the furnace fire (regardless of fuel), then open the starting valve, and the compressed air in the air storage cylinder enters the gas transmission pipe through the connecting pipe. Because the check valve prevents the compressed air from entering the high-pressure fan, it enters the heater and is heated by the heating device, and the temperature rises to about 500°C, the volume increases, and becomes a high-temperature and high-pressure working medium, and enters the steam turbine through the steam inlet pipe to impact the impeller to do work, and the steam turbine drives the high-pressure fan to operate; the air pressure of the air storage cylinder gradually decreases due to the gradual reduction of the compressed air in the cylinder. When the wind pressure generated by the high-pressure fan is greater than the air pressure of the air storage cylinder, the check valve automatically opens, and the high-pressure fan continuously presses the outside air into the heater, so that the air pressure of the heater and the air storage cylinder gradually increases. When the air pressure of the air storage cylinder increases to a level sufficient for the next start-up, the starting valve is closed. At this point, the present invention has completed the initial start-up process, and the time consumption is not much different from that of the gas turbine.

[0016] 2. The water supply system of the present invention can improve and adjust the output power; after the present invention completes the initial startup, air quickly enters the high-pressure fan. According to the principle of fluid mechanics, the water nozzle arranged at the air inlet of the high-pressure fan will be subjected to the effect of air suction. The water valve is opened, and under the action of atmospheric pressure, the water nozzle will spray water mist. The water mist enters the heater with the air and flows rapidly in the coil. When the small water droplets come into contact with the high-temperature tube wall, they quickly vaporize and expand rapidly to generate high-temperature and high-pressure steam. Therefore, the working medium of the present invention is changed from pure air to a mixture of air and steam; the contact area between the heater coil and the flue gas is large, and the heat transfer efficiency is high, so that the water droplets can be quickly vaporized into superheated steam regardless of the temperature; the larger the water valve is opened, the more water is sprayed and the more steam is generated. Compared with the original work done by pure air, air plus steam can do more work and the output power is greater, but the amount of water sprayed cannot exceed the vaporization capacity of the heater.

[0017] 3. Compared with the traditional steam turbine power system, the present invention does not have a bulky boiler, is small in size and light in weight, has good safety, low failure rate and good economy. The waste working fluid of the present invention is a mixture of air and steam (mostly air), with a higher temperature. The combustion-supporting gas used as fuel can recycle waste heat, and no blower is required.

[0018] 4. The present invention can also work when the water in the water supply system is completely exhausted, but the lack of steam in the working medium reduces the output power. The working principle at this time is similar to that of the gas turbine, except that one is external combustion and the other is internal combustion. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the present invention.

[0020] In the attached drawings, 1-high pressure fan, 2-gas supply pipe, 3-heater, 4-steam inlet pipe, 5-steam turbine, 6-exhaust pipe, 7-furnace, 8-combustion gas inlet pipe, 9-three-way regulating valve, 10-water tank, 11-water supply pipe, 12-water valve, 13-water nozzle, 14-gas storage cylinder, 15-starting valve, 16-connecting pipe, 17-waste steam pipe, 18-cover, 19-check valve, 20-economizer. DETAILED DESCRIPTION

[0021] The specific implementation of the invention is further described below with reference to the accompanying drawings.

[0022] In the description of the present invention, it is necessary to understand that the terms "center", "length", "width", "up", "down", "vertical", "horizontal", "top", "bottom", "inside" 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, 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 a limitation on the present invention.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0025] like Figure 1As shown, a quick-start steam turbine comprises a turbine system, a heating device, a water supply system and a starting device; the turbine system comprises a high-pressure fan 1, an air supply pipe 2, a heater 3, a steam inlet pipe 4, a steam turbine 5 and a steam exhaust pipe 6 which are connected in sequence, one end of the air supply pipe 2 is connected to the air outlet of the high-pressure fan 1, and the other end is connected to one end of the heater 3; the heater 3 is arranged in the heating device, the other end of the heater 3 passes through the heating device and is connected to one end of the steam inlet pipe 4, the other end of the steam inlet pipe 4 is connected to the steam inlet of the steam turbine 5, the steam exhaust of the steam turbine 5 is connected to one end of the steam exhaust pipe 6, and the steam turbine 5 is connected to the high-pressure fan 1;

[0026] The heating device includes a furnace 7, a combustion-supporting gas inlet pipe 8 and a three-way regulating valve 9, the inlet end of the three-way regulating valve 9 is connected to one end of the exhaust pipe 6, the outlet end of the three-way regulating valve 9 is connected to one end of the combustion-supporting gas inlet pipe 8, the other outlet end of the three-way regulating valve 9 is connected to one end 17 of the exhaust steam pipe, the other end of the combustion-supporting gas inlet pipe 8 is connected to the combustion-supporting gas inlet of the furnace 7, and the three-way regulating valve 9 can adjust the amount of the combustion-supporting gas entering the furnace 7 as needed; by providing the combustion-supporting gas inlet pipe 8 and the three-way regulating valve 9, the waste working medium of the steam turbine 5 can be used as the combustion-supporting gas of the fuel, and the waste heat can be recovered and utilized.

[0027] The water supply system includes a water tank 10, a water pipe 11, a water valve 12 and a water nozzle 13. One end of the water pipe 11 is connected to the water tank 10, and the other end is connected to the water nozzle 13. The water valve 12 is installed on the water pipe 11 and controls the on-off of the water pipe 11 and the water flow rate. The water nozzle 13 is set at the air inlet of the high-pressure fan 1. The water supply system can deliver mist water to the turbine system.

[0028] The starting device includes an air storage cylinder 14, a starting valve 15 and a connecting pipe 16 which are connected in sequence. The starting valve 15 is arranged at the air inlet and outlet ends of the air storage cylinder 14. One end of the connecting pipe 16 is connected to the starting valve 15, and the other end is connected to the air supply pipe 2 in a three-way shape.

[0029] In this embodiment, an openable cover 18 is provided at the air inlet of the high-pressure blower 1. When the blower is turned on, the cover 18 is opened so that mist water can enter the blower 1; when the blower is turned off, the cover 18 is closed so that the cover 18 covers the air inlet of the high-pressure blower 1, which can rapidly reduce the pressure in the steam inlet pipe 4, thereby rapidly stopping the operation of the steam turbine 5.

[0030] In this embodiment, a check valve 19 is installed between the high-pressure blower 1 and the gas pipe 2 , and the check valve 19 prevents the fluid from flowing from the gas pipe 2 into the high-pressure blower 1 .

[0031] In this embodiment, the water supply system also includes an economizer 20, which is installed in the middle of the water pipe 11. The water pipe 11 is connected to the water inlet and outlet of the economizer 20. The economizer 20 is installed at the end of the heating device and uses the waste heat of the flue gas to heat the water, thereby improving the heat utilization rate of the furnace 7.

[0032] In this embodiment, the heater 3 is installed in the furnace 7 in the shape of a multi-layer coil, and the heat transfer efficiency can be improved by the coil arrangement.

[0033] In this embodiment, one end of the power output end of the steam turbine 5 is connected to the power input end of the high-pressure blower 1. In addition, the steam turbine 5 is also provided with another output end for outputting power, which can be used for generating electricity, driving objects to move, and the like.

[0034] 1. Start-up operation: In the cold state, first turn on the heating device to ignite the furnace fire (regardless of fuel), then open the starting valve 15, the compressed air in the air storage cylinder 14 enters the gas transmission pipe 2 through the connecting pipe 16, and because the check valve 19 prevents it from entering the high-pressure fan 1, it enters the heater 3 and is heated by the heating device, the temperature rises to about 500°C, the volume increases, and becomes a high-temperature and high-pressure working medium, and enters the steam turbine 5 through the steam inlet pipe 4 to impact the impeller to do work, and the steam turbine 5 drives the high-pressure fan 1 to operate; the air pressure of the air storage cylinder 14 gradually decreases due to the gradual reduction of the compressed air in the cylinder, when the wind pressure generated by the high-pressure fan 1 is greater than the air pressure of the air storage cylinder 14, the check valve 19 automatically opens, the high-pressure fan 1 continuously presses the outside air into the heater 3, the air pressure of the heater 3 and the air storage cylinder 14 gradually increases, and when the air pressure of the air storage cylinder 14 increases to a level sufficient for the next start-up, the starting valve 15 is closed.

[0035] 2. Adjustment of output power: After the initial start-up, air quickly enters the high-pressure fan 1. According to the principles of fluid mechanics, the water nozzle 13 arranged at the air inlet of the high-pressure fan 1 will be subjected to air suction. The water valve 12 is opened. Under the action of atmospheric pressure, the water nozzle 13 will spray water mist, which enters the heater 3 with the air and flows rapidly in the coil. When the small water droplets come into contact with the high-temperature pipe wall, they quickly vaporize and expand rapidly to generate high-temperature and high-pressure steam. Therefore, the working medium of the present invention changes from pure air to a mixture of air and steam. The output power can be adjusted by adjusting the water valve 12 to adjust the water spray volume of the water nozzle 13.

[0036] 3. Shutdown operation: Covering the air inlet of the high-pressure blower 1 with a cover 18 can rapidly reduce the working pressure inside the machine, thereby rapidly stopping the operation of the steam turbine 5; completely closing the combustion-supporting gas inlet with the three-way regulating valve 9 can extinguish the fuel fire due to lack of oxygen.

[0037] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modified changes completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A quick-start steam turbine, comprising a turbine system, a heating device, a water supply system and a starting device; The turbine system comprises a high-pressure fan, an air delivery pipe, a heater, a steam inlet pipe, a steam turbine and a steam exhaust pipe which are connected in sequence, wherein one end of the air delivery pipe is connected to the air outlet of the high-pressure fan, and the other end is connected to one end of the heater; the heater is arranged in the heating device, and the other end of the heater passes through the heating device and is connected to one end of the steam inlet pipe, the other end of the steam inlet pipe is connected to the steam inlet of the steam turbine, the steam exhaust of the steam turbine is connected to one end of the steam exhaust pipe, and the steam turbine is connected to the high-pressure fan; The heating device comprises a furnace, a combustion-supporting gas inlet pipe and a three-way regulating valve, wherein the inlet end of the three-way regulating valve is connected to one end of the exhaust steam pipe, one outlet end of the three-way regulating valve is connected to one end of the combustion-supporting gas inlet pipe, the other outlet end of the three-way regulating valve is connected to one end of the exhaust steam pipe, the other end of the combustion-supporting gas inlet pipe is connected to the combustion-supporting gas inlet end of the furnace, and the three-way regulating valve can adjust the amount of combustion-supporting gas entering the furnace as needed; The water supply system includes a water tank, a water pipe, a water valve and a water nozzle. One end of the water pipe is connected to the water tank, and the other end is connected to the water nozzle. The water valve is installed on the water pipe and controls the on-off of the water pipe and the water flow rate. The water nozzle is arranged at the air inlet of the high-pressure fan. The water supply system can deliver mist water to the turbine system. The starting device comprises an air storage cylinder, a starting valve and a connecting pipe which are connected in sequence. The starting valve is installed at the air inlet and outlet ends of the air storage cylinder. One end of the connecting pipe is connected to the starting valve, and the other end is connected to the air supply pipe in a three-way shape.

2. A quick start steam turbine according to claim 1, characterized in that: An openable and closable cover is provided at the air inlet of the high-pressure blower.

3. A quick start steam turbine according to claim 1, characterized in that: A check valve is installed between the high-pressure blower and the gas pipe, and the check valve prevents fluid from flowing from the gas pipe into the high-pressure blower.

4. A quick start steam turbine according to claim 1, characterized in that: The water supply system also includes an economizer, which is installed in the middle of the water pipe. The water pipe is connected to the water inlet and outlet of the economizer. The economizer is installed at the end of the heating device and uses the waste heat of the flue gas to heat the water.

5. A quick start steam turbine according to claim 1, characterized in that: The heater is installed in the furnace in the shape of a multi-layer coil.

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