TW202136698A - Front booster system of condenser capable of enhancing power generation efficiency of steam turbine in thermal power plant capable of increasing the discharging speed of the exhaust steam of the steam turbine to reduce the back pressure of the condenser, thereby enhancing the power generation efficiency of the steam turbine - Google Patents

Abstract

This invention relates to a front booster system of a condenser capable of enhancing the power generation efficiency of a steam turbine in the thermal power plant, which is used to a steam turbines of a thermal power plant. The steam turbine uses steam as power and converts the thermal energy of the steam into mechanical work to drive the generator of the thermal power plant. After the pressurized steam passes through the steam turbine and drives the steam turbine, the steam will form exhaust steam and be discharged through the exhaust end of the steam turbine. The front booster system of condenser comprises a booster pump system including an inlet end, an outlet end, and at least one booster pump. The inlet end is connected to the exhaust end of the steam turbine. The exhaust steam discharged from the exhaust end of the steam turbine is input from the inlet end to the at least one booster pump to perform pressurization and then output from the outlet end. The outlet end of the booster pump system is connected to the condenser. The condenser is used to condense the pressurized exhaust steam from the booster pump system into water.

Description

Condenser pre-pressurization system capable of improving power generation efficiency of steam turbine in thermal power plant

The invention relates to a supercharging system used in a steam turbine of a thermal power plant, in particular to a condenser pre-supercharging system that can improve the power generation efficiency of a steam turbine of a thermal power plant.

In a thermal power plant, the main core equipment for power generation is a steam turbine, which uses the characteristics of the steam turbine to convert the thermal energy of steam into mechanical work to generate electricity. Usually the exhaust side of the steam turbine is equipped with a condenser. In addition to condensing the exhaust steam of the steam turbine into water for the boiler to reuse, the condenser can also form and maintain a vacuum at the exhaust steam of the steam turbine. The steam turbine and the condenser are connected by pipelines. The vacuum of the condenser will directly affect the efficiency of the generator. The reason is that the pressurized steam will lose power after passing through the steam turbine and drive the steam turbine to rotate. It directly affects the exhaust speed of the exhausted steam and the power efficiency of the steam turbine, and directly affects the power generation efficiency of the steam turbine.

At present, the exhaust steam of the steam turbine of a thermal power plant is usually input to the condenser by the natural migration of the pressure difference. In order to improve the power generation efficiency of the steam turbine, the common way is to try to reduce the back pressure value of the condenser, so that the steam turbine and the condenser The pressure difference between is maximized to accelerate the migration of steam and improve the power generation efficiency of the steam turbine. For some large generating units, within a certain range, every 1KPa increase in vacuum can reduce coal consumption by 3 grams per kilowatt-hour of electricity.

However, since condensers in thermal power plants basically use water as the condensing medium, these media It needs to rely on the cold source (water or air in the river, river, lake, sea) obtained from nature for cooling. Due to seasonal changes, the water temperature in the condenser will be affected by natural air temperature and water temperature. As we all know, water Saturated vapor pressure is related to temperature, so thermal power plants cannot keep the vacuum of the condenser close to the best vacuum required by the generator design all year round. This means that during most of the year, the working vacuum of the generator is not in the vicinity of the best vacuum that is most conducive to improving the efficiency of coal combustion.

In thermal power plants, there is usually a vacuum system at the back end of the condenser, and most of them are large water ring pumps or other forms of systems, and a few still retain the steam extraction system or the water jet pump extraction system. After the above vacuum system has formed the condenser into a vacuum state (a short time, usually no more than 2 hours), it is only used to maintain the vacuum degree of the condenser, which is to continuously extract the condenser in the continuous operation. For non-condensable gas, increase the pumping volume of these vacuum pumps to avoid the decrease of vacuum due to the inflow of non-condensable gas. However, for increasing the vacuum and reducing the back pressure value, due to the influence of the super large amount of water and the characteristics of low-pressure accelerated evaporation, increasing the pumping capacity of the vacuum pump set has a small effect on the improvement of the vacuum degree of the condenser.

Therefore, this case hopes to propose a new condenser pre-pressurization system that can improve the power generation efficiency of steam turbines in thermal power plants to solve the above-mentioned defects in the prior art.

Therefore, the purpose of the present invention is to solve the above-mentioned conventional technical problems. The present invention proposes a condenser front supercharging system that can improve the power generation efficiency of steam turbines in thermal power plants. The pressure pump system, using the mechanical air extraction mechanism of the pressure pump system, can change the natural exhaust method of the exhaust steam in the original steam turbine to forced exhaust, and can increase the exhaust speed of the steam turbine, which is equivalent to reducing the condensation The back pressure of the steam turbine can increase the power generation efficiency of the steam turbine, thereby saving the unit coal consumption required for the power generation of the steam turbine, and achieving the purpose of improving the power generation efficiency of the steam turbine of the power plant. And the power generation efficiency of the power plant is no longer affected by the ambient temperature, vacuum leakage and the size of the vacuum pump, so that the generator is optimized and not affected by the natural environmental temperature. The various booster pumps in the booster pump system of this case can be configured in series, in parallel, or multiple groups in series and then connected in parallel according to requirements, which can maximize the migration speed of exhaust steam. The biggest difference between this case and the vacuum system composed of the conventional power plant system and the existing retrofit technology is that a booster pump system is installed directly between the steam turbine and the condenser, rather than the application of a booster condenser on the market. Vacuum indirectly improves the power generation efficiency of the steam turbine. Therefore, the application of the structure of this case can effectively avoid the characteristics of the condenser that is affected by the cooling water temperature and leakage rate, and can more directly and efficiently make the system vacuum independent of the season. Stable in the section with the highest power generation efficiency of the steam turbine.

To achieve the above objective, the present invention proposes a condenser pre-pressurization system that can improve the power generation efficiency of steam turbines in thermal power plants. It is used in steam turbines in thermal power plants. The steam turbine uses steam as power and converts the thermal energy of the steam into mechanical work. Used to drive a generator in a thermal power plant; the steam turbine has an exhaust end. After the pressurized steam passes through the steam turbine and drives the steam turbine, the steam will lose power and form exhausted steam. The exhausted steam passes through the exhaust end to The condenser pre-pressurization system includes a booster pump system, including an inlet end, an outlet end, and at least one booster pump; the inlet end of the booster pump system is connected to the steam turbine via an input pipeline Each of the booster pumps includes an inlet end and an outlet end; exhaust steam discharged from the exhaust end of the steam turbine is input from the inlet end to the at least one booster pump for supercharging And then output from the outlet end; and a condenser includes an input end, the outlet end of the booster pump system is connected to the input end of the condenser via an output pipe; the condenser is used to receive the booster The supercharged exhaust steam in the pump system is condensed into water.

The features and advantages of the present invention can be further understood from the following description. Please refer to the Consider the attached drawings.

1: Steam turbine

2: Conveying pipeline

3: Booster pump

4: Condenser

5: Booster pump system

6: Vacuum system

7: Soda separator

11: Exhaust end

21: input pipeline

22: output pipeline

31: intake end

32: exhaust end

33: Valve

41: Input

42: output

51: Entry side

52: export side

71: Loop Liquid Heat Exchanger

81: drive motor

82: control mechanism

91: Cooling mechanism

92: Pressure sensor

93: temperature sensor

94: Temperature transmitter

Figure 1 shows a schematic diagram of the component assembly in this case.

The schematic diagram of the component combination in Figure 2 shows that the multiple booster pumps in this case are connected in series.

The schematic diagram of the component combination in Figure 3 shows that the multiple booster pumps in this case are connected in series, and the vacuum system is connected to a steam-water separator.

The schematic diagram of the component combination in Figure 4 shows that the multiple booster pumps in this case are connected in series, in which the condenser is connected to a steam-water separator.

The schematic diagram of the component combination in FIG. 5 shows that the multiple booster pumps in this case are connected in parallel.

The schematic diagram of the component combination in Fig. 6 shows that the multiple booster pumps in this case are connected in parallel, and the vacuum system is connected to a steam-water separator.

The schematic diagram of the component combination in Figure 7 shows that the multiple booster pumps in this case are connected in parallel, in which the condenser is connected to a steam-water separator.

The schematic diagram of the component combination in FIG. 8 shows that the multiple booster pumps in this case form multiple sets of booster pumps in parallel.

FIG. 9 shows a block diagram of the booster pump, related electrical components, and detection control circuit in this case.

With regard to the structural composition of this case, and the effects and advantages that can be produced, in conjunction with the drawings, a preferred embodiment of this case is described in detail as follows.

Please refer to Figures 1 to 9, which show the condenser pre-pressurization system that can improve the power generation efficiency of steam turbines in thermal power plants of the present invention, including the following components:

A steam turbine 1 has an exhaust end 11. After the pressurized steam passes through the steam turbine 1 and drives the steam turbine 1, the steam will lose power to form exhausted steam, and the exhausted steam is discharged outward through the exhaust end 11. Generally, the steam turbine 1 is a steam turbine for power generation in a thermal power plant. The steam turbine 1 uses steam as power and converts the thermal energy of the steam into mechanical work for driving the generator of the thermal power plant.

A booster pump system 5 includes an inlet port 51, an outlet port 52, and at least one booster pump 3. The inlet end 51 of the booster pump system 5 is connected to the exhaust end 11 of the steam turbine 1 via an input pipeline 21. Each of the booster pumps 3 includes an intake end 31 and an exhaust end 32. The exhaust steam discharged from the exhaust end 11 of the steam turbine 1 is input from the inlet end 51 to the at least one booster pump 3 to be pressurized and then output from the outlet end 52. The booster pump 3 is a Roots vacuum pump, a centrifugal pump, a turbine, a jet pump, or a gas moving power equipment with a large pumping capacity, etc., which can promote the gas migration speed. Therefore, the exhaust steam output by the steam turbine 1 is extracted mechanically by the at least one booster pump 3 to achieve the purpose of forced exhaust.

As shown in FIG. 1, the at least one booster pump 3 can be a single booster pump 3.

The at least one booster pump 3 may also be a plurality of booster pumps 3, and the plurality of booster pumps 3 may be connected in series or in parallel. As shown in FIG. 2, the multiple booster pumps 3 are connected in series to increase the pressure difference. The corresponding intake ends 31 and exhaust ends 32 of the two adjacent booster pumps 3 are connected to each other via the conveying pipe 2 to share the total boost or pressure drop in the booster pump system 5 to all levels. The booster pump 3 can share the heat generated by the need for compressed air, maintain the stable operation of each booster pump 3, and avoid jamming due to overheating.

As shown in Fig. 5, the multiple booster pumps 3 are connected in parallel, wherein the intake end 31 of all booster pumps 3 is connected in parallel to the input pipeline 21, and the discharge end 32 of all booster pumps 3 is connected in parallel to The output pipeline 22 is used to increase the overall amount of air pumped by the booster pump system 5.

As shown in Figure 8, the multiple booster pumps 3 can also form multiple groups of booster pumps 3 connected in parallel, and the corresponding intake end 31 and the exhaust end 32 of the two adjacent booster pumps 3 in each group Are connected in series via the delivery pipe 2, and the input pipe 21 is connected in parallel to the corresponding intake port 31 of the multiple groups of booster pumps 3, and the output pipe 22 is connected in parallel to the multiple groups of booster pumps 3 The corresponding exhaust end 32 can maximize the exhaust steam migration speed.

A condenser 4 includes an input end 41, and the outlet end 52 of the booster pump system 5 is connected to the input end 41 of the condenser 4 via an output pipe 22. The condenser 4 is used to receive the supercharged exhaust steam from the booster pump system 5 and condense the supercharged exhaust steam into water. The condenser 4 can be a water condenser, an air condenser, or other types of condensers.

This case can also include a vacuum system 6, wherein the condenser 4 further includes an output port 42 connected to the vacuum system 6, and the vacuum system 6 is used to extract the non-condensable gas in the condenser 4, A vacuum is formed inside the condenser 4.

As shown in Figures 3 and 6, this case can also include a steam-water separator 7, which can be connected to the vacuum system 6, and the steam-water separator 7 is used to separate the steam-water mixture output from the vacuum system 6 into air. And liquid water, and the liquid water is input to the steam-water separator 7, and the working water with suitable water temperature is formed by the loop liquid heat exchanger 71 and returned to the vacuum system 6 to serve as the vacuum system 6 Working loop fluid required for operation.

As shown in Figures 4 and 7, the vacuum system 6 may not be configured in this case, and the steam-water separator 7 is directly connected to the output port 42 of the condenser 4, and the steam-water separator 7 condenses the steam. The steam-water mixture output by the device 4 is separated into air and liquid water.

A valve 33 is installed at the intake end 31 of each booster pump 3 to close the corresponding booster pump 3 when needed to make it out of the operation of the entire booster pump system 5 to improve the booster pump system. 5 available Reliability and maneuverability.

Each of the booster pumps 3 forms a passage (not shown in the figure), so even if a booster pump 3 is stopped, the exhausted steam can still pass through the unused booster pump 3, so the steam turbine 1 will not be caused. It cannot be used without causing safety hazards to the original system.

FIG. 9 shows a block diagram of the electromechanical components of the booster pump 3, which are mainly used to display related electrical components and detection control circuits.

The booster pump 3 is connected to a driving motor 81, and the driving motor 81 is connected to a control mechanism 82, and the driving motor 81 is controlled by the control mechanism 82 to drive the booster pump 3. The control mechanism 82 can control the drive motor 81 in a frequency conversion manner, and regulate the performance of the booster pump 3 according to the characteristics of the frequency conversion. The frequency conversion start can maintain the safe and stable operation of the booster pump 3. Low-frequency operation can deeply save energy, and high-frequency operation can give full play to the boosting performance of the booster pump 3. Using frequency conversion to adjust the operating speed of the booster pump system 5 can increase or decrease the boost pressure, and adjust the vacuum degree of the system in a larger range, so that the vacuum degree of the system throughout the year is in the best vacuum condition required by the generator. In order to prevent the generator from being affected by climate, season and weather, and improve the working efficiency of the generator throughout the year.

Each of the booster pumps 3 is further connected to a cooling mechanism 91, and the cooling mechanism 91 is used to input cooling water to the booster pump 3 for cooling.

Each of the booster pumps 3 is further equipped with a pressure sensor 92 and a temperature sensor 93. The pressure sensor 92 is used to detect the pipeline pressure of the booster pump 3, and the temperature sensor 93 is used to detect the pressure of the booster pump 3. temperature. The pressure sensor 92 and the temperature sensor 93 are connected to the control mechanism 82. The pressure value and temperature value detected by the pressure transmitter 93 and the temperature transmitter 94 are transmitted to the control mechanism 82 to control the drive motor 81 and the cooling mechanism 91 to protect the booster pump 3 from being stable run.

The booster pump system 5 in this case can be supported by a fixed bracket (not shown in the figure), and this structure is Those who are familiar with the conventional technology will not repeat the details.

The advantage of this case is that a booster pump system is added between the steam turbine and the back-end condenser, and the mechanical air extraction mechanism of the booster pump system can be used to change the natural exhaust method of the exhausted steam in the original steam turbine to forced exhaust. , And can increase the exhaust steam exhaust rate of the steam turbine, which is equivalent to reducing the back pressure of the condenser, thereby improving the power generation efficiency of the steam turbine, thereby saving the unit coal consumption required for the power generation of the steam turbine, achieving the purpose of improving the power generation efficiency of the steam turbine of the power plant, and making the power plant The power generation efficiency is no longer affected by the ambient temperature, vacuum leakage and the size of the vacuum pump, so that the generator is optimized and not affected by the natural environmental temperature. The various booster pumps in the booster pump system of this case can be configured in series, in parallel, or multiple groups in series and then connected in parallel according to requirements, which can maximize the migration speed of exhaust steam.

The biggest difference between this case and the vacuum system composed of the power plant system in the prior art and the existing retrofit technology is that the booster pump system is directly installed between the steam turbine and the condenser, rather than on the market (including the inventor) The previously invented condenser vacuum energy saving system) uses vacuum equipment such as mechanical pumps or steam pumps behind the condenser to increase the vacuum of the condenser to indirectly improve the power generation efficiency of the steam turbine. Therefore, the application of the structure in this case can effectively avoid condensation The characteristics of the condenser affected by the cooling water temperature and the leakage rate can make the system vacuum degree not affected by the season more directly, more significantly and more efficiently, and it is always stable in the range of the highest power generation efficiency of the steam turbine.

In summary, the humanized and considerate design of this case is quite in line with actual needs. Compared with the conventional technology, the specific improvement of the existing defects is obviously a breakthrough advantage, and it does have an increase in efficacy, and it is not easy to achieve. This case has not been disclosed or disclosed in domestic and foreign documents and markets, and it has complied with the provisions of the Patent Law.

The above detailed description is a specific description of a possible embodiment of the present invention, but this embodiment It is not intended to limit the scope of the patent of the present invention. Any equivalent implementation or modification that does not deviate from the technical spirit of the present invention shall be included in the patent scope of this case.

1: Steam turbine

3: Booster pump

4: Condenser

5: Booster pump system

6: Vacuum system

7: Soda separator

31: intake end

32: exhaust end

33: Valve

41: Input

42: output

51: Entry side

11: Exhaust end

21: input pipeline

22: output pipeline

52: export side

71: Loop Liquid Heat Exchanger

Claims (14)

A condenser pre-pressurization system that can improve the power generation efficiency of steam turbines in thermal power plants. It is used in steam turbines in thermal power plants. The steam turbine uses steam as power and converts the thermal energy of the steam into mechanical work to drive the generators in thermal power plants. The steam turbine has an exhaust end. After the pressurized steam passes through the steam turbine and drives the steam turbine, the steam will lose power and form exhaust steam, which is exhausted through the exhaust end; The condenser pre-pressurization system includes: A booster pump system includes an inlet end, an outlet end, and at least one booster pump; the inlet end of the booster pump system is connected to the exhaust end of the steam turbine via an input pipeline; each booster pump includes an inlet An air end and an exhaust end; the exhaust steam discharged from the exhaust end of the steam turbine is input from the inlet end to the at least one booster pump to be pressurized and then output from the outlet end; and A condenser includes an input end, and the outlet end of the booster pump system is connected to the input end of the condenser via an output pipe; the condenser is used to receive the supercharged exhaust from the booster pump system. And condense the supercharged exhaust steam into water. In the condenser pre-vacuum system described in item 1 of the scope of patent application, the at least one booster pump is a single booster pump. In the condenser pre-vacuum system as described in item 1 of the scope of patent application, the at least one booster pump is a plurality of booster pumps, and the plurality of booster pumps are formed in parallel. The condenser pre-vacuum system described in item 1 of the scope of patent application, wherein the at least one booster pump is a plurality of booster pumps, and the plurality of booster pumps are formed in series to increase the pressure difference; wherein The corresponding intake ends and exhaust ends of two adjacent booster pumps are connected to each other via a conveying pipeline. The condenser pre-vacuum system as described in item 1 of the scope of patent application, wherein the booster pump is A gas pump that promotes gas migration speed. The condenser pre-vacuum system as described in item 1 of the scope of patent application, wherein the booster pump is selected from roots vacuum pumps, centrifugal pumps, or turbines, jet pumps, or gas mobile power equipment with large pumping capacity . For example, the condenser pre-vacuum system described in item 1 of the scope of patent application, wherein a valve is installed at the intake end of each booster pump to close the corresponding booster pump when necessary to separate it from the entire booster pump. The operation of the pressure pump system. The condenser front vacuum system as described in item 1 of the scope of patent application, wherein the condenser is a water condenser or an air condenser. The condenser pre-vacuum system described in item 1 of the scope of patent application further includes a vacuum system, wherein the condenser further includes an output end connected to the vacuum system, and the vacuum system is used to extract the The non-condensable gas in the condenser makes the inside of the condenser to form a vacuum. The condenser pre-vacuum system as described in item 9 of the scope of patent application further includes a steam-water separator, wherein the vacuum system is connected to the steam-water separator, and the steam-water separator is used for the steam-water output from the vacuum system The mixture is separated into air and liquid water. The condenser pre-vacuum system described in item 1 of the scope of patent application further includes a steam-water separator, wherein the condenser further includes an output end connected to the steam-water separator, and the steam-water separator is used for the condenser The steam-water mixture output by the steamer is separated into air and liquid water. The condenser pre-vacuum system as described in item 1 of the scope of patent application, wherein the booster pump is connected to a driving motor, the driving motor is connected to a control mechanism, and the driving motor is controlled via the control mechanism to drive the booster pump ; Each of the booster pumps is still connected to a cooling mechanism, the cooling mechanism is used to input cooling water to the booster pump for cooling. For example, the condenser pre-vacuum system described in item 12 of the scope of patent application, wherein the control mechanism uses a frequency conversion method to control the drive motor, and regulates the performance of the booster pump according to the frequency conversion characteristics. For example, the condenser pre-vacuum system described in item 12 of the scope of patent application, wherein each of the booster pumps is further equipped with a pressure sensor and a temperature sensor; the pressure sensor and the temperature sensor are connected to the control mechanism; the pressure transmission The pressure value and temperature value detected by the sensor and the temperature transmitter are transmitted to the control mechanism to control the drive motor and the cooling mechanism to protect the booster pump from operating stably.

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